Bacterias Flashcards
STAPHYLOCOCCUS AUREUS
“The golden staff of Moses”
STAPHYLOCOCCUS AUREUS
“The golden staff of Moses”
What does Staphylococcus Aureus literally mean?
Staphylococcus (grape like)
Aureus (gold in color)
Gram type of Staphylococcus Aureus?
Gram Positive Cocci
What tests can be used to determine Staphylococcus Aureus?
Catalase (+)
Coagulase (+)
Beta Hemolytic (+)
Mannitol (+)
What is the main virulence factor on Staphylococcus Aureus and how does it work?
Protein A; Main virulence factor on staph aureus.
Protein A is a component of S. Aureus cell wall and
it can bind to the FC region of antibodies and this will prevent compliment from occurring.
Preventing opsonization and phagocytosis.
Where does Staphylococcus Aureus mainly colonize?
S. Aureus will colonize the nares
What are the 10 possible diseases that can be caused with Staphylococcus Aureus?
- Gastroenteritis
- Acute bacterial endocarditis
- Abscesses and mastitis (Humps with red cloth - Really large erythematous abscesses)
- Toxic shock syndrome
- Impetigo
- Scalded Skin Syndrome (SSS)
- Pneumonia
- Surgical infections
- Osteomyelitis
- Septic Arthritis
What causes the coughing in Staphylococcus Aureus infection?
Coughing - Pneumonia
Patchy infiltrate on x-ray
What is the shape of the capsule of the virus that will infect after a Staphylococcus Aureus infection?
Icosahedron shaped capsule of the virus that will infect after a S. Aureus infection.
What is Staphylococcus Aureus is the most common cause of in adults? (Hint: 2 diseases)
Septic Arthritis and Osteomyelitis.
In Staphylococcus Aureus acute endocarditis, what is the most common cause of it and where does it affect it in the heart?
IV drug use
Tricuspid valve Endocarditis
What mediates Scalded Skin Syndrome in a Staphylococcus Aureus infection?
Scalded skin syndrome mediated by a protease
What causes Toxic Shock Syndrome in a Staphylococcus Aureus infection?
Toxic Shock Syndrome, commonly caused by leaving a bandage in or a tampon which causes nonspecific binding of MHC II to T cell receptors causing over-reaction and Cytokine storm.
What does a Catalase test measure?
Turns hydrogen peroxide –> water
What does a Coagulase test measure?
Fibrinogen –> fibrin
What does a Beta Hemolytic test measure?
When looking at petri dish with B-hemolysis it looks like a glowing halo of light.
Beta-hemolysin breaks down the red blood cells and hemoglobin completely. This leaves a clear zone around the bacterial growth.
What does a Mannitol test measure?
If it CAN ferment manitol it will turn the agar to yellow.
If it CAN’T ferment manitol the agar will stay pink.
What is the treatment of choice for Staphylococcus aureus infection?
Nafcillin/oxacillin are drugs of choice because of widespread antibiotic resistance.
“Naf for Staph”
What is the treatment for methicillin-resistant Staphylococcus aureus (MRSA)?
Vancomycin
What is the treatment for vancomycin-resistant Staphylococcus aureus (VRSA) or vancomycin- intermediate S. aureus (VISA)?
quinupristin/dalfopristin
STAPHYLOCOCCUS EPIDERMIDIS AND STAPHYLOCOCCUS SAPROPHYTICUS
“Beauty and the Plumber”
STAPHYLOCOCCUS EPIDERMIDIS AND STAPHYLOCOCCUS SAPROPHYTICUS
“Beauty and the Plumber”
Staphylococcus epidermidis and Staphylococcus saprophyticus are what type of gram?
Gram (+)
Staphylococcus epidermidis and Staphylococcus saprophyticus are Catalase + or -?
Catalase Positive
Staphylococcus epidermidis and Staphylococcus saprophyticus are Urease Positive. What does that mean?
Urea –> ammonia
How are Staphylococcus epidermidis and Staphylococcus saprophyticus separated from staph aureus?
Staph epidermidis and Staph saprophyticus are coagulase negative
Why is Staphylococcus epidermidis considered Ortopedic’s enemy?
- Hardware - Infects hardware or orthopedic joints
- Tubing - Catheter tubes, Indwelling catheters are also important spots of infections
- Heart valves - Infection of heart implants - endocarditis of artificially implanted heart valves
How is Staphylococcus epidermidis able to affect tools?
Uses biofilms to stick to sleek metal and plastic surfaces, these are polysaccharides that protect them from antibiotics and immune cells.
TXT of Staphylococcus Epidermidis endocarditis?
Vancomycin for TXT of Staph Epidermidis endocarditis
Where can Staphylococcus Epidermidis be found?
Normal Skin Flora
Staphylococcus Epidermidis is sensitive or resistant to a certain drug?
Novobiocin Sensitive
What disease is mainly caused by Staphylococcus saprophyticis infection?
UTI’s in Sexually Active Females.
Staphylococcus saprophyticis is sensitive or resistant to a certain drug?
Novobiocin resistant
Who is more at risk for Staphylococcus sapropytics infection?
Sexual active females
GROUP A STREPTOCOCCUS (STREPTOCOCCUS PYOGENES)
“The Pie Genies’ Bakery”
GROUP A STREPTOCOCCUS (STREPTOCOCCUS PYOGENES)
“The Pie Genies’ Bakery”
Group A Streptococcus are:
encapsulated or no capsulated?
Encapsulated
What is the capsule of the Streptococcus Pyogenes made of?
Hyaluronic Acid
Where do we produce Hyaluronic Acid in our bodies?
Connective Tissue so everywhere in our body so it cannot be immunogenic or else our own immune system would constantly be attacking us.
What tests can be done with Streptococcus Pyogenes?
B-Hemolytic
What are the symptoms Streptococcus Pyogenes can cause?
Impetigo
Pharyngitis (aka Strep throat), red inflamed throat
Erysipelas (its a very superficial cellulitis infection), red lesion with well demarcated borders, S Pyogenes is the most common cause.
What is the toxin of the Streptococcus Pyogenes?
Streptococcal Pyrogenic Exotoxin (SPE)
SPE A
SPE B
SPE C
What are the diseases that can be caused by the Streptococcus Pyogenes toxin?
Scarlett Fever
Toxic Shock Like Syndrome (TSLS)
Necrotizing Fasciitis
What are the three main symptoms of Scarlett Fever?
a. “Strawberry Tongue” - reddening and swelling of the tongue
b. Pharyngitis
c. Diffuse (widespread) rash that spares the face.
What is Toxic Shock Like Syndrome mediated by?
Super Antigen SpeA, SpeC
What is the Necrotizing Fasciitis mediated by?
SpeB
What are the two highly tested conditions (complications) pretending to Streptococcus Pyogenes?
Rheumatic Fever (RF)
Post Streptococcus Glomerulonephritis (PSGN)
What is the main virulence factor for Rheumatic Fever and how does it function?
M protein in GAS (Group A Strep) is the main virulence factor for Rheumatic Fever, will interfere with opsonization, antiphagocytic, M protein will mimic antibodies in heart and cause issues with Mitral Valve in the heart.
How does M protein function?
Antiphagocytic action
Very antigenic and elicits a humoral response, creating an antibodies to a very similar antigen and in this case myosin in cardiac muscle (Molecular mimicry), thus, damages mitral valves (can cause a mitral stenosis)
Pharyngitis precipitates RF, NOT IMPETIGO
When does Rheumatic Fever occur?
AFTER Streptococcus pharyngitis infection.
Does NOT happen after skin infections.
Does NOT happen after prompt treatment of pharyngitis, which is why it happens more in young children with little access to Healthcare.
Pharyngitis precipitates RF, NOT IMPETIGO”
What kind of hypersensitivity reaction is Rheumatic Fever?
Hypersensitivity type II reaction
What is the criteria used for Rheumatic Fever?
JONES criteria
J: Joints –> polyarthritis
O: <3 : “heart problems” –> valvular damage leading to new murmurs, myocarditis, paricarditis.
N: Nodules (subcutaneous nodules): nodules on extensor surfaces (forearms, elbows, knees)
E: erythema marginatum: rash with nice thick borders
S: Sydenham’s Chorea: rapid involuntary especially of hands and face
What causes the Post Streptococcus Glomerulonephritis (PSGN)?
Our own immune system.
After a streptoccocus infection, unlike RF the damage isn’t a type2 hypersensitivity reaction, its a type 3 hypersensitivity, which means the damage is from circulating antibody antigen immune complexes that eventually deposit in the glomerulus.
What are the 2 main symptoms for Post Streptococcus Glomerulonephritis (PSGN)?
Facial edema - puffy cheeks w/ nephritis
Cola colored Urine
When does Post Streptococcus Glomerulonephritis (PSGN) occur?
Occurs 2 weeks after the onset of the initial streptococcus infection.
What is a way to differentiate RF and PSGN?
RF: can occur only after pharyngitis
PSGN: can occur after pharyngitis or superficial infection like impetigo
Treatment and complication prevention:
Early diagnosis and treatment of Strept throat can prevent RF but it cant prevent PSGN.
What is the treatment for Streptococcus pyogenes infection?
Penicillin
What are 3 more virulence factors for Streptococcus pyogenes?
a. Streptolysin O: allows Group A Streptococcus to lyse RBC to be Beta Hemolytic, we generate antibodies to Streptolysin O (called ASO antibodies).
b. Streptokinase, converts plasminogen to plasmin. Plasmin is fibrinolytic. So Streptokinase is given as medication to lyse clots to MI or Ischemic strokes.
c. DNA’ases, depolymerize DNA and really least important to know.
What does “kinase” mean?
To put a phosphate on something
How do we differentiate Group A Streptococcus and Group B streptococcus?
Group A Streptococcus is Bacitracin sensitive.
Group B Streptococcus is Bacitracin resistant.
How can we test if a patient recently had a Group A streptococcus infection?
Check ASO titers to see if there was a Group A Strep Infection since we create antibodies against it.
We generate antibodies to Streptolysin O (called ASO antibodies).
Antistreptolysin O titer
What is the Mnemonic for Virulence factors of Streptococcus pyogenes?
“SMASHED”
Streptolysins M protein Anti-C5a peptidase Streptokinase Hyaluronidase and Hyaluronic acid Capsule Exotoxin (SPE-A, SPE-B, SPE-C) DNAses
STREPTOCOCCUS AGALACTIAE
“Galactic Baby (Group B Streptococcus)”
STREPTOCOCCUS AGALACTIAE
“Galactic Baby (Group B Streptococcus)”
Streptococcus agalactiae is gram positive or negative?
Gram Positive (“purple plante”)
What tests can be done to check for Streptococcus agalactiae?
Hippurate Positive
CAMP test positive
B-hemolytic
What does a Hippurate test measure?
Hydrolyzes sodium hippurate.
What does CAMP test measure?
Distinguishes Streptococcus agalactiae with all other streptococcus!
Similar to staphylococcus Aureus, when GBS is plated with Staph aureus, it has increasing zone of hemolysis.
What kind of capsule does Streptococcus Agalactiae have?
Polysaccharide capsule
What does Bacitracin do to streptococcus agalactiae?
Nothing, its Bacitracin resistant.
What is the main concern with a streptococcus agalactiae and its also the first thing you should think about is:
Causes Meningitis in neonates (#1 cause of meningitis in neonates).
What else can streptococcus agalactiae also cause?
Most likely to cause meningitis sepsis and also causes pneumonia.
What can you see in petri dish of streptococcus agalactie?
a arrowhead is the arcuate that forms in the zone of hemolysis.
How can a neonate get a streptococcus agalactiae infection?
When neonates passes through the vaginal canal of the mother during delivery.
Part of prenatal care, how and when do we check for streptococcus agalactiae?
Week 35 the vagina and rectum is swabbed to see if she is colonized by streptococcus agalactie.
What is GBS infection?
Group B Strep infection
What is the prevention for streptococcus agalactiae?
Profilaxis: Penicillin will be given to mom intrapartum to prevent group B strep.
STREPTOCOCCUS PNEUMONIA & STREPTOCOCCUS VIRIDANS
“The Alpha Knight Tournament”
STREPTOCOCCUS PNEUMONIA & STREPTOCOCCUS VIRIDANS
“The Alpha Knight Tournament”
Is streptococcus pneumonia gram positive or gram negative?
Gram Positive
Is streptococcus pneumonia alpha or beta hemolytic?
a-hemolytic which means theres partial hemolysis where the surrounding zone is a green hue. This green comes from the oxidation from hemoglobin.
What kind of capsule does streptococcus pneumonia have and why is it important?
Polysaccharide capsule which is a major virulence factor.
Streptococcus pneumonia is sensitive to something. what is it?
Optochin sensitive, optochin inhibits the growth of streptococcus pneumonia
What does streptococcus pneumonia look like under a microscope?
“Double Lance” - Lancet shaped diplococci
Streptococcus pneumonia is soluble to what?
Bile soluble, meaning it does not grow in bile
What kind of pneumonia does streptococcus pneumonia lead to and how does the sputum look like?
Lobar pneumonia that generally infiltrates the lower lobes.
Rust colored sputum.
Streptococcus pneumonia is the number one cause of which diseases?
Community acquired pneumonia
"MOPS" Meningitis Otittis Media Pneumonia Sinusitis
Streptococcus Pneumonia has another virulence factor other than its capsule that helps it avoid our immune system. What is it?
IgA Protease: Protease that cleaves IgA that allows invasion of mucosa reducing host defenses.
Helps it invade and colonize our mucosa, reducing host’s defenses
Who is at a greater risk of getting infection of encapsulated microorganisms?
Spleenectomy or autospleenectomy as in the case of Sickle cell disease (asplenia). This is because the spleen plays a major role of removing encapsulated organisms from the body.
Removal of spleen leads to susceptibility of infection by encapsulated organisms like in sickle cell anemia.
What is the TXT for streptococcus pneumonia infection?
Macrolides (azithromycin)
3rd gen cefalosporin: Ceftriaxone
How can we prevent a streptococcus pneumonia infection?
Adult is a 23 valiant polysaccharide vaccine.
Children is 7 valent but conjugated to a protein.
Adults will have a T-Cell independent response creating IgM that does not last long. Adding the protein adds a more robust antigen response leading to a production of IgG in children.
What kind of capsule does Streptococcus viridians have?
its NOT encapsulated
Streptococcus viridians is resistant to what?
optochin
What happens to streptococcus viridians when it is put with bile?
it is resistant
What other species are part of the streptococcus viridans?
Streptococcus mutants
Streptococcus sanguinis
What can streptococcus mutants and Streptococcus sanguinis lead to?
dental plaque, dental carries
What happens if Streptococcus viridian gets in the blood?
subacute endocarditis in damaged heart valves most commonly mitral valve.
Strep Sanguineous adheres to fibrin platelet aggregates in damaged heart valves, most commonly occurs in mitral valve.
How can Streptococcus viridians do so much damage to the heart?
Synthesizes Dextran’s (think of it like a glue) from glucose which allows strep viridians to adhere to any fibrin from platelets that has been damaged in the heart.
ENTEROCOCCUS FAECALIS & ENTEROCOCCUS CAUCUS
“Protest at the Caucus”
ENTEROCOCCUS FAECALIS & ENTEROCOCCUS CAUCUS
“Protest at the Caucus”
What are the two species of the enterococcus genus?
Enterococcus Faecalis (California) Enterococcus Faecium (Stop the Fees)
Which species of enterococcus is more common?
Enterococcus Faecalis (California)
Which species of enterococcus is more dangerous and why?
Enterococcus Faecium (Stop the Fees), Nosocomial infection resistant to almost every antibiotic we have.
Vancomycin resistant as well (VRE: Vancomysin Resistant Enterococcus)
Both enterococci can grow in mediums of?
Can grow in mediums up to 6.5% sodium chloride
What is enterococcus resistant against?
Bile resistant
What are the main symptoms of enterococcus infections?
DO U <3 T?
U: UTI
<3: Endocarditis
T: Infection of the Biliary Tree
What is the treatment for enterococcus infections?
“Police Line” - Linezolid
“tiger stripes” - Tigacycline
NEISSERIA SPECIES
“Noir Series”
NEISSERIA SPECIES
“Noir Series”
Neisseria is gram positive or gram negative?
Gram negative
neisseria: oxidase positive or negative?
Oxidase positive
What kind of shape does neisseria have?
Dipplicocci (“double hand cuffs”)
What are the agars used for neisseria?
Chocolate agar (its a heated blood agar).
CANT use blood agars since its inhibited by some of lipids/other elements in blood agar unless heated therefore chocolate agar.
VPN agar (Thayer Martin Agar)
What is a VPN agar?
VPN special agar enriched with vancomycin, polymixin, and nystatin
Can be used for Neisseria.
What is another name for VPN agar?
Thayer martin AKA VPN agar
What deficiency causes an increase susceptibility to neisseira species?
MAC complex deficiency due to complex c5-c9 deficiency.
MAC Deficiency unable to form the MAC complex due to complex c5-c9 being inhibited. Patients with c5-c9 deficiency are unable to form MAC complex, leading to increased infections.
MAC = Membrane Attack Complex
What are the virulence factors of Neisseria species?
Virulence Factors
a. Pilli allows attachment to surfaces and display antigenic variation which makes our immune system difficult to target neisseria and prevent any lasting immune response.
b. IgA protease will cleave IGA at its hinge point, facilitates survival along mucosal surfaces.
NEISSEIRA MENINGITIDES
“A SHOCKING DEATH ON CAMPUS”
NEISSEIRA MENINGITIDES
“A SHOCKING DEATH ON CAMPUS”
How does neisseria meningitis spread?
Easily spread in areas with a lot of people, military recruits, college dorms via respiratory droplet
Neissiria meningitis is gram ____________.
Gram negative - Red Hue
What does Neisseiria meningitis ferment?
meningitis ferments maltose and glucose.
Only meningitis ferments maltose
Where does neisseria meningitis first colonize?
Colonizes nasopharynx first, transmitted by respiratory secretions (kissing, sharing drinks, close contacts, sneezing, coughing)
What kind of capsule does neisseria meningitis have?
Polysaccharide capsule that inhibits phagocytosis and its considered its major virulence factor.
How can neisseria meningitis be prevented?
Before SDSU I had to get a shot - the Meningococcal vaccine
It was a vaccine for A,C,D polysaccharide capsules but not B.
Which type of neisseria meningitis accounts for most infections in USA and most developed countries?
Type B since theres no vaccine for it.
Who are more susceptible to neisseria meningitis infection?
Sickle cell and asplenic patients are more susceptible to Neisseria meningitides because it is encapsulated (just like Strep pneumonia!)
What is the physiopathology of neisseria meningitis infection?
N. Meningitides Invades hemotogenously leading to a massive inflammatory response generated by LOS (lipooligiosaccharides) proteins, these are Neisseria’s version of LPS, it grows so much of it that it outgrows the surface area of the bacteria and begins blabbing off.
These blebs of LOS envelope that lead to a massive inflammatory response.
MOST IMPORTANT QUESTION; PATHOGENOSIS:
What does the inflammatory response of neisseria meningitis lead to?
Inflammation leads to leaky capillaries, which leads to characteristic petechial rash leading to thrombocytopenia leading to DIC (Disseminated Intravascular Coagulation)
–> oozing at venopuncture sites, bleeding gums
Capillary leakage can lead to hypovolemia and shock.
Vasoconstriction will go to max to attempt to maintain blood pressure and adrenals can infarct and will contribute to shock (Waterhouse fritter syndrome)
What is the mortality rate of neisseria meningitis infection?
15% mortality rate even with antibiotic treatment.
What is the treatment for neisseria meningitis infection?
3rd generation cephalosporin that can penetrate the blood brain barrier like ceftriaxone
What is Waterhouse fritter syndrome?
Waterhouse fritter syndrome, characterized by hemorrhage of adrenals caused by capillary leak that leads to hypovolemia/shock.
Can be caused by neisseria meningitides.
What is the profilaxis treatment for someone who had close contact?
Rifampin.
Who should be given a profilaxis treatment with someone infected with neisseria mengitis?
Close contact is someone who had more than 8 hours with someone infected during the seven days prior to onset should be given rifampin.
NEISSERIA GONORRHEA
“The Violinists Last Clap”
NEISSERIA GONORRHEA
“The Violinists Last Clap”
How do you get neisseria gonorrhea infection?
Sexually Transmitted Disease
What kind of shape and gram type is neisseria gonorrhea?
Gram Negative Diplococci
what kind of cells are neisseria gonorrhea and what kind of cells do they like to invade?
Facultative intracellular in PMNs
The cells they like to invade are polymorphonuclear lymphocytes (PMNL)
What kind of capsule does neisseria gonorrhea have?
NOT encapsulated
What happens in males when they are affected with neisseria gonorrhea?
Urethritis
Prostatitis
Orchiditis
What happens in females when they are affected with neisseria gonorrhea?
- Pelvic Inflammatory Disease (PID) - can lead to scarring which leads to infertility or ectopic pregnancy.
- Purulent White Charge - which is characteristic of Gonorrhea (can occur to both men and women), generally more thicker and purulent in appearance than chlamydia which tends to be more thin and watery.
- PID can spread to the peritoneum which causes: Fitz Hugh Curtiss syndrome
- May cause polyarthritis in the knee and is asymmetric.
What is Fitz Hugh Curtiss syndrome?
Fitz Hugh Curtiss syndrome: A further complication of the peritoneum is that the infection of the peritoneum can lead to adhesions that form to the capsule of the liver and these long and thin adhesions are referred to as “violin string adhesions”
A joint tap will show purulent synovial fluid that doesnt gram stain, why is that?
Thats because the infection is intracellular.
How can a baby be infected with neisseria gonorrhea?
During delivery if the mother has untreated gonaccocal infection.
What is the first symptom seen in a newborn with neisseria gonorrhea infection?
Gonococcal Conjunctivitis occurs generally during within the first five days.
Chlamydia conjunctivitis occurs after a first week of birth.
What is the TXT of choice for neisseria gonorrhea infection?
Ceftriaxone but if you put that on USMLE its WRONG.
Co infections with Chlamydia are super common so treat for both: Ceftriaxone + Macrolide (such as: azithromycin or doxycycline)
BACILLUS ANTHRACIS + BACILLUS CEREUS
“King Anthra’s Axe”
BACILLUS ANTHRACIS + BACILLUS CEREUS
“King Anthra’s Axe”
What is characteristic symptom of bacillus anthracis infection?
Black Eschar with erythematous ring
Black Eschar: black necrotic cutaneous lesion with a surrounding erythematous ring
What is the capsule of bacillus anthracis and bacillus cereus?
Capsulated with Poly-D Glutamate (capsule is made up of protein instead of the usual polysaccharides)
What is the shape and gram type of bacillus anthracis and bacillus cereus and what disease does it create?
Large Gram positive rods in a chain (unusual to see them in a chain)
Bacillus anthracis, a gram positive bacterium, is the causative agent of anthrax. This organism is capsulogen and toxinogenic.
What does bacillus anthracis and bacillus cereus need to survive?
It is obligate aerobe (can only survive in the presence of oxygen)
How does bacillus anthracis survive?
Bacillus anthracis is a spore forming bacteria allowing them to survive in very poor environments. The spores hibernates without any significant metabolic activity and with a sturdy protective covering its highly resistant to temp/chemicals, so its able to survive an extremely long time in almost any environment.
Think of: 2001 anthrax attacks, also known as Amerithrax.
What are the two important spore forming organisms?
bacillus and clostridium species.
MOST TESTABLE QUESTIONS:
what are the two toxins of bacillus anthracis?
It secretes two toxins which are composed of three proteins: the protective antigen (PA), the lethal factor (LF) and the edema factor (EF).
How does edema factor (EF) work in bacillus anthracis?
EF toxin functions as adenosine cyclase.
It increases cAMP intercellularily this will cause fluid to go extracellular space leading to edema inhibiting host defenses and indirectly preventing phagocytosis
How does lethal factor (LF) work in bacillus anthracis?
LF (lethal Factor), exotoxin that acts as a protease and cleaves MAP Kinase, this is a signal transduction protein that is responsible for cell growth.
This factor (MAP Kinse) will lead to necrosis and black eschar.
What is wool sorter’s disease and what are its symptoms?
pulmonary anthrax, wool sorters disease. Spores can get into wool and hide of animals and persist there. People will inhale the spores when the animal is handled. Then germs in the lungs and cause pulmonary symptoms.
Starts with no specific pulmonary symptoms.
Dry cough.
medianstinal lymph nodes Hemorragic medianstinitis (looks like widen mediastinum on x-rays) Pulmonary Hemorrhage (almost 100% mortality rate)
What is the TXT bacillus anthracis when caught early?
fluoroquinolone (drug of choice)
doxycycline (secondary treatment)
physical characteristics of Bacillus cereus?
Aerobic and spore forming
How can you get sick with Bacillus cereus?
Food poisoning
reheated fried rice and vomitting
CLOSTRIDIUM TETANI
“Rhesus Research Revolution”
CLOSTRIDIUM TETANI
“Rhesus Research Revolution”
Clostridium tetani: gram positive or negative?
gram positive
What kills Clostridium tetani?
Obligate anaerobes (cannot survive in the presence of oxygen)
How do Clostridium tetani survive?
spore forming
How does Clostridium tetani invade our bodies?
Clostridium is found in the dirt and enters the body through a puncture wound.
Rusty nails, barbed wire
Spores found in rusty nails, and in soil
Puncture wound occurs either by nail or barbed wire with tetany spores on it, spores are embedded in the flesh and the organism vegetates and stays at the wound site. It will release tetanus toxin that will cause all the symptoms
What are the symptoms accompanied with Clostridium tetani?
- Relentless muscle contractions: Spastic paralysis leading to rigidity
- Opisthosomas - exaggerated arching of the back
- rhesus sardonicus = evil smile, evil grin
IMPORTANT TEST QUESTION:
Describe pathogenesis of Clostridium tetani.
Tetanus toxin will travel retrograde through the motor axons to the spinal cord.
Tetanus toxin acts as a protease will cleave a protein named “snare” and will inhibit exocytosis of the neurotransmitter into the synapse (GABA and glycine) or Renshaw cells.
2 type of inhibitory neurons, GABA and glycine. If these are inhibited it will result in uncontrolled firing of the motor neurons leading to spastic paralysis.
Renshaw cells will sense over activity of nearby motor neurons and when they sense this activity they will attempt to fire and inhibit the motor neuron. So the GABA and Glycine release from these cells is inhibited leading to spasm
Describe to Clostridium tetani vaccine.
It is a toxoid Vaccine which means toxin conjugated to a protein to increase immunogenicity.
This produces an antibody response to the toxin, not to the organism.
CLOSTRIDIUM BOTULINUM
“Robotulism”
CLOSTRIDIUM BOTULINUM
“Robotulism”
clostridium botulinum: gram type?
Gram positive
How is clostridium botulinum transmitted?
Spore forming.
transmitted by improper canning of food allowing it to flourish in the anaerobic environment producing heat stable toxin.
“a family are presenting with the same neural symptoms” make the dang connection on these kind of questions!!!
what kills clostridium botulinum?
Obligate anaerobe
What symptoms will a patient present with clostridium botulinum infection?
Flaccid paralysis, descending paralysis. Opposite of Guillen barre syndrome. Multiple people is most likely botulism, not Guillen barre.
for example, multiple people who went camping showing these symptoms will be botulinum most likely, NOT Guillen barre.
What kind of paralysis is presented in clostridium botulinum infection?
descending paralysis: diplopia, ptosis
How is the paralysis produced in a clostridium botulinum infection??
to demonstrate the descending paralysis, toxin is unable to cross BBB so only peripheral nervous system is affected.
NOT the central nervous system since it cant cross BBB.
How does the toxin function in a clostridium botulinum infection?
Cleavage of SNARE protein similar to Tetany toxin, only difference is that botulism attacks motor neurons that release Ach, inhibiting motor neuron release leading to flaccid paralysis.
Toxin is a protease that cleaves SNARE proteins.
How do adults get infected with clostridium botulinum infection?
The spores must first germinate in an Anaerobic environment (canned food) and produce the toxin in that environment. Then adults ingest that PREformed toxin.
Ingestion of pre formed antigen from improperly canned foods.
Whats a food that can cause infantile botulism?
Spores in the Honey
Infantile botulism transmitted through ingestion spores in the honey.
How do babies get infected with clostridium botulinum infection?
Ingestion of spores; honey
What syndrome do babies get with clostridium botulinum infection and why is it caused?
Toxin effects similar to babies and cause flaccid paralysis “Floppy Baby Syndrome”
Babies lack robust flora of gut that can out compete Clostridium botulinum will be colonized with spores if they ingest honey. Then they will produce the toxin and have floppy baby syndrome.
Why don’t adults get sick from ingesting infected honey?
clostridium botulinum is a wimp and cant compete with our normal adult flora even though our gut is anaerobic environment, while babies lack this competition.
Whats more common: Adult or Infantile botulism?
Infantile botulism
CLOSTRIDIUM DIFFICILE
“Field Trip to the Chocolate Factory”
CLOSTRIDIUM DIFFICILE
“Field Trip to the Chocolate Factory”
What the street name of clostridium difficile?
King of Diarrhea Bed pan's Worst nightmare C-Dif Chocolate factory pseudomembranous colitis.
What does clostridium difficile for?
Spore forming
What kind of diarrhea is clostridium difficile?
Nosocomial diarrhea (people are affected while hospitalized), spores easily transferred from patient to patient, antibiotics will wipe out normal flora making patients immunocompromised and able to be colonized then create the toxin.
Which is one of the main antibiotics that will cause clostridium difficile?
Clindamycin and poorly washed hands can cause it. Clindamycin is one of the main antibiotics that will cause this.
What are the 2 exotoxins that are produced by clostridium difficile?
Exotoxin A
Exotoxin B
Describe the 2 exotoxins that are produced by clostridium difficile?
Exotoxin A - Binds to the brush border of the intestine and causes inflammation, cell death and watery diarrhea.
“Brush border toxin causing diarrhea”
Exotoxin B - disrupts cytoskeleton integrity by
depolymerizing actin leading to enterocyte death and necrosis. Yellowish grey exudate that forms a pseudomembrane that covers the colonic mucosa. This is why clostridium difficile infection is called a pseudomembranous colitis.
How can you diagnose Clostridium difficile?
PCR: look for the toxin –> Assay to detect TOXIN (not the bacteria that is screened) in stool that will be detected downstream
Clostridium difficile cant survive with?
Obligate anaerobe
Clostridium difficile: Gram type?
Gram positive
What is the treatment for Clostridium difficile?
Oral vancomycin + Metronidazole
Why is oral vancomycin used for treatment?
IV vancomycin wont deliver to lumen of intestine. So its taken orally. Vancomycin also has poor absorption rate orally so its good for side effects minimization.
CLOSTRIDIUM PERFRINGENS
“Private Ringen’s Motorcycle Accident”
CLOSTRIDIUM PERFRINGENS
“Private Ringen’s Motorcycle Accident”
How does clostridium perringens spread?
Spores are formed in dirt and soil
How is one infected with clostridium perringens?
Classic Presentations: (deep military wounds, motorcycle accidents).
Large amounts of flesh are exposed to dirt and dust.
What is clostridium perringens afraid of?
Obligate anaerobe
What are the 2 diseases that clostridium perfingens create?
- clostridial myonecrosis: Causes Gas Gangrene after it enters the wound, gas produced under tissue and has a cracking sound on palpation. Gas is produced as the organism consumes carbohydrates.
- Slow onset diarrhea due to spores needing to reproduce in the gut then create the toxin.
What is the main toxin in clostridial myonecrosis?
This is due to Alpha toxin that effects lipid bilayer and lyses RBC’s which causes hemolysis.
Myonecrosis involves alpha toxin, which is a lecithiinase (phospholipase), which cleaves lecithin which causes damage cell membranes by damaging the lipoproteins.
what the heck is “Double zone of hemolysis”?
Lecithinase can cause red cell hemolysis both in vivo and in vitro.
So when you plate it, it has a zone of hemolysis but its unique that it forms double zone of hemolysis.
What is the TXT for clostridium perfingens?
IV penicillin G
CORYNEBACTERIUM DIPHTHERIAE
“Heart of the Bull Fight”
CORYNEBACTERIUM DIPHTHERIAE
“Heart of the Bull Fight”
Gram type of corynebacterium diphtheriae and its spore type and its shape?
Gram positive, Non-spore forming
Club shape and y or v Shape
What does corynebacterium diphtheriae stain with?
Metachromatic granules that stain with aniline dyes, Metachromatic granules will stain red and the rest of the cell will stain blue.
Describe the 2 exotoxins and its functions of corynebacterium diphtheriae.
Subunit A (active subunit) Toxin causes Ribosylation of Elongation Factor 2 (EF-2), this will inhibit ribosome function inhibiting protein synthesis leading to cell death. This will lead to pseudomembranous exudate that will be found in the oral pharynx.
Subunit B (binding subunit)
Where are the pseudomembranes of corynebacterium diphtheriae found?
pseudomembranes Found in throat and tonsils because the infection is transmitted by respiratory droplets, Can cause airway obstruction and lymphopathy, this will cause bulls neck (thickening of the neck).
What happens when the corynebacterium diphtheriae toxin gets into the blood stream?
It can have systemic effects both on heart and nervous system:
Can cause life threatening myocarditis. Can present arrhythmia and heart block. (lethal effect of diphtheria)
Local paralysis that generally begin in posterior pharynx and can lead to cranial nerve deficits. This is because the corynebacterium diphtheriae toxin will damage the myelin of nerve fibers.
How can you culture test corynebacterium diphtheriae?
Need culturing or toxin assey.
So swab those grayish membranes and plate them on 2 special agars:
plate on Tellurite and Loeflers media
How can you differentiate between toxin and nontoxic strains of corynebacterium diphtheriae?
Eleks test - in-vitro assay on filter paper that has antitoxin on it.
So if toxin binds to it, theres a reaction and the strain is considered toxic.
Which vaccine is used for corynebacterium diphtheriae?
DTaP vaccine is used, often given with tetanus and pertussis vaccine.
Can produce a very powerful IgG response.
Toxoid Vaccine (consists of inactivated exotoxin that of protein)
Which type of patient are most likely to get corynebacterium diphtheriae?
Immigrants since USMLE thinks they dont vaccinate outside USA
What is the treatment for a non vaccinated corynebacterium diphtheriae infection?
Passive immunization (administrating antitoxoid)
LISTERIA MONOCYTOGENES
Santa’s List
LISTERIA MONOCYTOGENES
Santa’s List
Listeria monocytogenes: gram positive or gram negative?
Gram positive
Who are most likely to get sick from a Listeria monocytogenes infection?
Pregnant women are more likely (20 times more) to get listeria than anyone else.
May lead to termination or disease in the newborn
Which test can be done to identify Listeria monocytogenes?
B-hemolytic
Catalase positive
Describe Listeria monocytogenes physically.
Motile and facultative intracellular, tumbling motility extracellular
How does Listeria monocytogenes get around?
Rapidly polymerizes actin along the cell wall allowing it to move quickly in the cell.
Rocket “ Actin Rocket” intracellular movement
can even move from cell to cell
Where does listeria monocytogenes likes to survive and multiply?
Listeria survives and multiplies in near freezing temperatures
What does listeria monocytogenes contaminate?
Can contaminate food items even if they are refrigerated, like milk, cheese
what does listeria monocytogenes do to a new born?
Newborns can get meningitis from the mom, can also get in in adults over 60
Its the 3rd most common cause of meningitis, after Streptococcus B and E. Coli.
What should you tell a pregnant woman about listeria monocytogenes?
Don’t eat soft cheeses.
What is the TXT for listeria monocytogenes?
Ampicillin
PROTEUS MIRABILIS
“The God of the Public restroom”
PROTEUS MIRABILIS
“The God of the Public restroom”
proteus mirabilis: gram type?
Gram negative
What happens to proteus mirabilis when plated?
Demonstrates swarming motility
Is Proteus mirabilis facultative aerobe or facultative anaerobe?
Facultative anaerobe
What diseases can Proteus mirabilis cause?
Kidney Stones
UTI
Tests that can be used for Proteus mirabilis?
Urease positive
H2S positive
What kind of environment gators a struvite stone formation?
Alkaline environment can cause struvite stone formation.
Why is it to know that proteus mirabilis is urease positive?
may form stag horn calculi = kidney stones within pelvis
Ammonia means urease positive, this is what makes the stag horn calculi, to struvite stones causing pain and kidney stones, alkaline formation causes kidney struvite stones.
What kind of odor does a proteus mirabilis infection have?
Fishy odor
What is the TXT for a proteus mirabilis infection?
Sulfonamides
What are struvite stones made of?
Formed of ammonia, magnesium, and phosphate.
YERSINIA ENTEROCOLITICA & PESTIS
“YERSINS PETS”
YERSINIA ENTEROCOLITICA & PESTIS
“YERSINS PETS”
Gram type of Yersinia enterocolitica?
Gram Negative
How does yersinia enterocolitica spreads?
Primarily transmitterd through puppy feces
Contaminated Milk products (like Listeria)
Who are the most common individuals infected with yersinia enterocolitica?
Toddlers, Children (duh!) (since they play with puppies)
What is yersinia enterocolitica resistant to?
Resistant to cold temperatures (like listeria)
Whats so special about yersinia enterocolitica staining?
Stains Heavily on two ends
What is the main virulence factor of yersinia enterocolitica?
Encapsulated virulence factor
What is the main symptom of yersinia enterocolitica?
Bloody diarrhea (invasive)
Invasive systemic effects like fever, intestinal issues, leukocytosis, abscesses, major bowel movements
TEST QUESTION:
What is the main manifestation of yersinia enterocolitica?
Mimics appendicitis
right lower quadrant pain, fever, other classic symptoms of appendicitis like elevated WBC
What is another name for Yersinia Pestis?
Bubonic plague (25 million people dead)
How is Yersinia Pestis spread?
Transmitted through human as incidental host, usually with rats or prairie dogs.
“Rodents” with fleas, then fleas bite humans
What are the symptoms presented in Yersinia Pestis infection?
Forms Buboes (thats why its called Bubonic plague) with swollen tender lymph nodes.
Cause abscesses in organs once it gets in the blood or DIC from endotoxin and neurotoxin
What is the virulence factor of Yersinia Pestis?
Yersinia outer proteins that inhibit macrophages through a type 3 secretion system, inhibiting phagocytosis
What is the TXT for Yersinia Pestis?
?????
What is the prevention for Yersinia Pestis?
Killed vaccine is used to vaccinate
SHIGELLA SONHEI & SHIGELLA DYSENTERIAE
“She-Gorilla’s Circus”
SHIGELLA SONHEI & SHIGELLA DYSENTERIAE
“She-Gorilla’s Circus”
Gram type and indole for shigella?
Gram negative
Indole positive
What are the two main symptoms of shigella?
Gastroenteriitis
Bloody Diahrrea
Which type of agar is used for shigella and how does it look?
Green colonies on Hektoin agar (salmonella makes black colonies)
Special characteristic of shigella?
Immotile
What kind of state is shigella found it that makes it so dangerous?
It is acid stable, needs far fewer microorganisms to cause infection (salmonella needs far more)
What are the two types of shigella?
Shigella sonnei and shigella dysenteriae
Which of the two types of shigella is the most common in united States?
Shigella sonnei
What makes shigella lead to inflammation?
non-lactose, non H2S, LPS(endotoxin) leads to inflammation
What kind of secretion does shigella have?
type III secretion
TEST QUESTION:
describe the pathogenesis of shigella.
Shigella induces M Cells (they are like scouts; they sample things in the lumen and bring back antigens to immune cells on the other side of the intestinal epithelium) in peyers patches to phagocytose them and they escape from the phagolysosome to prior to destruction.
Once in the cytoplasm they will use the host cells actin cytoskeleton to create a tail it can use to propel itself from one cell to the other (like actin rockets in listeria/or like a using M cells as a trojan horse)
Since shigella can survive inside its own cell or in another, what is the name for that?
Facultative intracellular, just like salmonella
TEST QUESTION:
Why does bloody diarrhea occur in shigella?
Once shigella has invaded lymphoid tissue and enterocytes, it Damages tissue and releases cytokines that will inflame the tissues causing a large immune response, clinically we will see fecal blood and leukocytes: bloody diarrhea (underlying inflammatory diarrhea)
TEST QUESTION:
What is the toxin in shigella and how does it work?
Shiga Toxin will bind to the 60s unit of ribosomes and inhibit translation,
TEST QUESTION:
What is hemolytic uremic syndrome (HUS)?
Once shigella invades, it releases a toxin “shigatoxin”, once in blood, shigatoxin enduces endothelial damage, including in the glomerular of kidney. Activates platelets and induces their aggregation, diminishing pool of circulating platelets thus drop in platelets.
The aggregates of platelets protruding out of the endothelium, lyse RBCs they pass by, literally cutting them in half so they look like helmets or shistocytes,
This is pahotgenesis of HUS
Leads to hemolytic uremic syndrome (HUS) in younger children most commonly under 10 years of age.
Progerminal diarrhea following with acute renal failure (glomerular damage).
Form shistocytes
What does shigella use to cause inflammation?
Uses a type 3 secretion system to release inflammatory cytokines
What is the treatment for shigella?
treatment with Macrolides and Fluoroquinolones
ESCHERICHIA COLI & ENTEROHEMORRHAGIC E. COLI & ENTEROTOXIGENIC E. COLI
“E. Cola’s Soda Fountain”
ESCHERICHIA COLI & ENTEROHEMORRHAGIC E. COLI & ENTEROTOXIGENIC E. COLI
“E. Cola’s Soda Fountain”
Gram type of Escherichia coli?
Gram Negative
Which type of agar is used for Escherichia Coli?
Grow pink on MacConkey’s agar
One of the most defining feature of Escherichia Coli?
Lactose fermenter (milk)
What is the main virulence factor of Escherichia coli?
Capsular K antigen
Flagellar H antigen
E coli is also encapsulated with which antigen?
Capsular K antigen
Which test is positive for Escherichia coli?
Catalase positive
oxidase negative
Facultative anaerobic
What happens when Escherichia coli grows on EMB agar?
Eosin methylene blue (EMB, also known as “Levine’s formulation”)
Creates a green sheen
What is the #1 cause of UTI’s?
Escherichia coli (about 80%)
What does Escherichia coli have that allows it to cause UTI?
Fimbriae that will lead to UTI’s #1 cause of UTI’s
What else is Escherichia coli leading cause of?
Gram negative sepsis
What is the virulence factor of Escherichia coli that causes sepsis?
LPS endotoxin (lipopolysaccharide endotoxin) in outer cell membrane
How can Escherichia coli cause neonatal meningitis?
Causes neonatal meningitis only if it has the K antigen
Enterohemorrhagic Escherichia coli (EHEC) most commonly transmitted through what?
Undercooked meat
What is the main symptom of Enterohemorrhagic Escherichia coli (EHEC)?
Bloody diarrhea
Enterohemorrhagic Escherichia coli (EHEC) is the only Escherichia coli that doesn’t do what?
Doesn’t ferment sorbitol
Whats the toxin in Enterohemorrhagic Escherichia coli (EHEC) and what can it cause?
Toxin inhibits ribosomes at the 60s position. Shiga like toxin is the name and can cause hemolytic uretic syndrome (HUS).
Describe the pathogenesis of Enterohemorrhagic Escherichia coli (EHEC) toxin.
Shige like toxin damages endothelial cells of capillaries in the glomerulus. Damaged endothelial lining causes platelets to adhere decreasing platelet count causing thrombocytopenia and these platelets clumps will hemolysis RBC. Little to no fever but mucosal inflammation or invasion.
Which antigen of Enterohemorrhagic Escherichia coli (EHEC) is associated with outbreaks?
O157: H7
Enterohemorrhagic Escherichia coli (EHEC) other name?
Traveler’s diarrhea
Montezuma’s revenge
Whats the most common cause of Enterotoxigenic Escherichia coli (ETEC)?
Recent travel to Mexico where they drank the water.
What are the two toxins Enterotoxigenic Escherichia coli (ETEC) produces?
Heat Labile toxin produces cAMP
Heat Stable toxin produces cGMP
What is the main symptom of Enterotoxigenic Escherichia coli (ETEC)?
Watery Diarrhea
What is the treatment for Escherichia coli?
TMP/SMX or fluoroquinolones
What is the differences between Enterohemorrhagic Escherichia coli (EHEC) and Enterotoxigenic Escherichia coli (ETEC)?
EHEC bloody diarrhea
ETEC watery diarrhea
CAMPYLOBACTER JEJUNI
“Camping Guy and the Bears”
CAMPYLOBACTER JEJUNI
“Camping Guy and the Bears”
Gram type of campylobacter jejuni?
Gram negative
What does campylobacter jejuni look like?
Spiral/curved rod bacilli - enteric
What is the perfect environment for campylobacter jejuni to grow on?
Prefers warm environments around 42 degrees Celsius, thermophile (special incubator)
In which medium does campylobacter jejuni grow on?
Skirrow agar
What is the main reservoir of campylobacter jejuni?
Intestinal tract of poultry and other animals
What is the transmission of campylobacter jejuni?
Fecal oral/ also contaminated water supplies or ingestion of raw milk
TEST QUESTION:
What symptoms can be expected with campylobacter jejuni?
Bloody stools and diarrhea
Bacteremia, invasive
Reactive arthritis (Rider’s syndrome) sero-negative spondyloartropathies that can be precipitated by campylobacter jejuni infection
Can cause Guillen barre syndrome
TEST QUESTION:
When does Guillen Barre syndrome occur?
Occurs after being infected with bacterial and viral infections.
Campylobacter being the most classic.
TEST QUESTION:
What is the difference between botulism and Guillen barre syndrome?
Botulism = descending paralysis
Guillen Barre = ascending paralysis
TEST QUESTION:
What happens in Guillen Barre syndrome?
Occurs after being infected with bacterial and viral infections.
Campylobacter being the most classic. The body can have an autoimmune response that causes demyelination of peripheral nerves leading to an ascending paralysis that will start at the feet and then ascend.
Campylobacter oxidase positive or negative?
Oxidase positive
TEST QUESTION:
Pathogenesis of Campylobacter jejuni?
Bacteria colonize intestinal mucosa and attach to epithelial cells then replicate intracellularly causing and acute PMN response, edema of the mucosa and ulcerations. Presenting with acute enteritis and diarrhea.
TEST QUESTION:
What is the main symptom of Guillen barre syndrome?
Ascending paralysis
What is the TXT for campylobacter jejuni infection?
Supportive care
ENTEROBACTER CLOACAE, SERRATIA MARCESCENS, KLEBSIELLA PNEUMONIAE
“Enterodactyl, Triserratiatops, and the Kleb-Tailed Dinosaur”
ENTEROBACTER CLOACAE, SERRATIA MARCESCENS, KLEBSIELLA PNEUMONIAE
“Enterodactyl, Triserratiatops, and the Kleb-Tailed Dinosaur”
Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae are considered what type of infections?
nosocomial infections
What are the two most common infections caused by Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae?
Pneumonia, UTI
They are nosocomial infections.
What makes Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae so hard to treat?
Multi Drug Resistant Carbopenam for treatment or Clindamycin
Which agar is used on Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae?
MacConkey’s Agar
What can Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae ferment?
All 3 ferment lactose: turns it pink along with E coli on MacConkey’s agar
What is a special characteristic of enterobacter cloacae?
Very motile
What is are special characteristic of serratia marcescens?
Very motile
Red pigment when cultured like a pink ring around shower or bright red
Catalase positive
Which of the three Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae is immotile?
klebsiella pneumoniae
What are the 3 “A”s of klebsiella pneumoniae?
Alcoholics (commonly affects them)
Abscesses (commonly creates abscesses)
Aspiration (commonly started from aspirations)
What kind of capsule does klebsiella pneumoniae have?
Polysaccharide capsule
How can you tell klebsiella pneumoniae is the cause of a patient’s pneumonia?
Patients cough up a current jelly like sputum that is a red color.
X-Ray - Cavatary lesion on patients right lobe “tb like”
What klebsiella pneumoniae positive for?
urease positive
What is the treatment used for Enterobacter cloacae, serratia marcescens, klebsiella pneumoniae infections?
3rd generation ceftriaxone, cefotaxime
HELICOBACTER PYLORI
“The Helicopter Pilot”
HELICOBACTER PYLORI
“The Helicopter Pilot”
Shape and gram type of Helicobacter pylori:
Curved gram negative rod
How does Helicobacter pylori move around?
motile by the way of flagella
where is Helicobacter pylori found in?
helical slender curved rod shape found in pylorus of the stomach
TEST QUESTION:
What is a major virulence factor of Helicobacter pylori?
It is urease positive urea into ammonia and CO2 which helps reduce acidity of environment (stomach) which is absolutely necessary for Helicobacter pylori invade the stomach.
TEST QUESTION:
What can you do to screen for Helicobacter pylori?
- Can be screened with Urea breath test where patients swallow urea with labelled with radioactive carbon, which is then split into CO2 and ammonia and this CO2 now with radioactive carbon is exhaled. Radioisotopes are detected in exhalation then that means there is a urease positive organisms in your stomach.
- Biopsy during endoscopy and then directly check for urease with rapid test.
Helicobacter pylori is a curved rod. All curved rods are ________.
oxidase positive.
TEST QUESTION:
What does Helicobacter pylori mainly cause?
Causes 95% of all duodenal ulcers.
Why do we get ulcers with Helicobacter pylori?
Mechanism of Chronic infection causes increased acid production by either reducing somatostatin or increasing production of gastrin.
What happens if you dont care about Helicobacter pylori?
At risk of developing gastric adenocarcinoma (almost half of gastric adenocarcinoma are linked to H. pylori).
Patient can develop lymphoma of mucous associated lymphoid tissue (MALToma)
Whats lymphoma of mucous associated lymphoid tissue (MALToma)?
MALT lymphoma (MALToma) is a form of lymphoma involving the mucosa-associated lymphoid tissue (MALT), frequently of the stomach, but virtually any mucosal site can be afflicted.
It is a cancer that is linked with untreated H. pylori infection.
How do you treat a Helicobacter pylori infection?
Triple therapy (sometimes can be used quadruple therapy):
- Proton Pump Inhibitor (PPI):(to counter increased acid production caused by chronic H. pylori)
- Amoxicillin
- macrolide - Clarithromycin
What is the transmission for Helicobacter pylori infection?
fecal oral or oral
PSEUDOMONAS AERUGINOSA
“The Suiters of pseudo Mona”
PSEUDOMONAS AERUGINOSA
“The Suiters of pseudo Mona”
Pseudomonas Gram type?
Gram Negative
Pseudomonas shape type?
Rod
In what kind of environments does pseudomonas thrive in?
Thrives in aquatic environments
“hot tub folliculitis” = pruritic papular pustular folliculitis
What are tests used for pseudomonas?
Catalase positive
Oxidase positive
Which disease heightens risk for pseudomonas?
Chronic granulomatous Disease (associated with catalase positive)
TEST QUESTION:
What are some dead give aways for pseudomonas?
Produces Blue green pigment when plated, may even turn wounds blue. Its from Pyocuanin and pyoverdin that pseudomonas produce.
Fruity Grape like odor.
Obligate _________ for pseudomonas.
Obligate aerobe
Pseudomonas is the most common cause of? (2 diseases)
Most common Gram Neg Nosocomial Pneumonia.
Most common cause of respiratory failure in Cystic Fibrosis (CF) patients since it has a nonfunctional Chlorine ion channels in CF.
TEST QUESTION:
What are the diseases pseudomonas can cause?
Gram Neg Nosocomial Pneumonia.
Respiratory failure in CF patients.
Osteomyelitis in IV drug users and Diabetics.
Skin lesions (pruritic papular pustular folliculitis - people using under chlorinated hot tubs or cutaneous necrosis “ecthyma gragrenosusm).
Ear infection (otitis externa)
How can pseudomonas survive?
Encapsulated
Who is especially susceptible for pseudomonas?
Burn patients are especially susceptible.
What are some was a patient can get pneumonia infection in the hospital?
Indwelling catheter infections from UTI’s, chamber pot, nosocomial UTI’s.
What are the two different types of skin lesions that can be caused by pseudomonas?
pruritic papular pustular folliculitis - people using under chlorinated hot tubs
cutaneous necrosis “ecthyma gangrenosum”
What part of the head does psudomona affect?
Ear infection (otitis externa)
What is the name of the pseudomonas toxin?
Exotoxin A
TEST QUESTION:
Describe the pathogenicity of pseudomonas.
Exotoxin A - Ribosolation of elongation factor 2, leads to inhibition of protein synthesis and cell death
pseudomonas and what other bacteria have nearly the same toxin and in what sense are they the same?
diphtheria - same mechanism and targets
Mechanism: ribosolated
Target: Elongation Factor 2
What is the TXT for pseudomonas?
first treatment: Piperacillin (antipseudomonal penicillin) + tazobactam
Other treatment: Aminoglycosides and fluoroquinolones
SALMONELLA TYPHI & SALMONELLA ENTERITIDIS
“The Salmon Dinner”
SALMONELLA TYPHI & SALMONELLA ENTERITIDIS
“The Salmon Dinner”
Salmonella Gram type?
Gram positive
Salmonella Agar type?
White on MacConkey
Black colonies on Hecktor on agar plate
is salmonela motile?
YES
Salmonella is H2S positive, what does that mean?
All motile enteric colonies stain black on Hecktor on agar plate
Salmonella is indole negative. why?
Indole negative due to lack of tryptophanase
Is salmonella capsulated?
Yes, positive for citrate utilization turns indicator blue due to alkaline pH
Salmonella is acid labile, what does that mean?
Acid labile = easily degraded in the stomach which means it needs high doses to cause an infection
Which kind of patients are more susceptible to infection of salmonella?
Patients on proton pump inhibitor more susceptible to infection since it lowers acidity of the stomach
TEST QUESTION:
Describe pathogenicity of Salmonella.
Invades through the stomach, small intestine, colon and then the lymphatics.
Then taken up by the macrophages to get into the blood, it is facultative intracellular (within macrophages)
How do we get Salmonella enteritidis infections?
By eating undercooked Chicken (main reservoir)
Where do chronic Salmonella typhi carriers harbor the bacteria?
Gall blader, thyphoid mary
What are the main symptoms of Salmonella enteritidis?
Causes:
inflammatory diarrhea
gastroenteritis
What might you find on a physical examination on a patient with salmonella typhi?
rose colored macules on their stomach due to infection (only happens 25% of the time)
Salmonella typhi is the number 1 cause of what and in which type of patients?
Number 1 cause of osteomyelitis in adults with sickle cell disease
How is salmonella enteritidis able to increase infectivity?
Contains type 3 secretion system that detects eukaryotic cells that will increase infectivity.
This is a protein that detects eukaryotic cells and when it does it will secrete a protein that will increase infectivity.
How is the diarrhea in salmonella typhi described?
“pea soup” diarrhea
What is the name of the disease created by salmonella typhi?
Typhoid fever
What is the source of Thyphoid fever?
ALWAYS human source, “Typhoid Mary”
Typhoid is spread by eating or drinking food or water contaminated with the feces of an infected person.
Individuals can develop typhoid fever after ingesting food or water contaminated during handling by a human carrier. The human carrier may be a healthy person who has survived a previous episode of typhoid fever yet who continues to shed the associated bacteria, Salmonella typhi, in feces and urine. Washing hands with soap before touching or preparing food, washing dishes and utensils with soap and water, and only eating cooked food are all ways to reduce the risk of typhoid infection.
TEST QUESTION:
Which strain of salmonella has a vaccine and what kind of vaccine is it?
salmonella typhi: Live, attenuated vaccine
TEST QUESTION:
You might think a patient has salmonella infection but only has gastroenteritis, which antibiotics will you prescribe?
gastroenteritis antibiotics not warranted, do NOT use antidiarrheal
TEST QUESTION:
How is salmonella typhi treated and specify when to use them.
Antibiotics (fluoroquinolone) or a cephalosporin (cefttriaxone)
Flouroquinalones: ciprofloxacin/levofloxacin
TEST QUESTION:
When should you use fluoroquinolone in compared with cephalosporin when dealing with salmonella typhi?
Ceftriaxone: for Invasive and bloody
TEST QUESTION:
What is Salmonella septicemia and why is it important in consideration with the CDC?
Salmonella septicemia is a condition wherein the presence of Salmonella bacteria in the blood triggers a potentially life-threatening, whole-body inflammatory response.
Recurrent Salmonella septicemia is classified as an AIDS-defining condition by the U.S. Centers for Disease Control and Prevention (CDC).
TEST QUESTION:
What is the TXT for Salmonella septicemia?
Chloraphenicol, ampicillin, amoxicillin, or TMP/SMX for 10 days
TEST QUESTION:
What is TMP/SMX?
trimethoprim/sulfamethoxazole
Brand and Other Names:Bactrim, Bactrim DS, Septra, Septra DS, Cotrim, cotrimoxazole, Sulfatrim
Classes: Sulfonamides; Antibiotics, Combos
TEST QUESTION:
What are the three phases of Salmonella Typhi?
- After sufficient bacteria have multiplied in the intestines there is a manifestation of lethargy dull frontal headache, CONSTIPATION, rise in body temp. binds to
Phase 2: Development of a bacteremia, patients have fever and are severely ill with a Dull Expressionless look, rose spots develop mainly on the trunk
Phase 3: Second Bacteremia occurs from reinfection of biliary tract, pus in stools and bleeding in peyers patches, Ileum Necrosis
Whats the most used Proton Pump Inhibitor?
Omeprazol 40 mg IV
VIBRIO CHOLERAE, VIBRIO PARAHAEMOLYTICUS, VIBRIO VULNIFICUS
“Colonel Cholera’s Base cAMP”
VIBRIO CHOLERAE, VIBRIO PARAHAEMOLYTICUS, VIBRIO VULNIFICUS
“Colonel Cholera’s Base cAMP”
Gram type of vibrio cholerae?
Gram negative
Shape of vibrio cholerae?
Comma Shaped curved rod
Type of bacteria of vibrio cholerae?
Enteric Tract Bacilli
Where is Vibrio Cholerae endemic in?
SouthEast Asia
Which agar is used for Vibrio cholera?
TCBS agar
Oxidase postive or negative for vibrio cholera?
Oxidase positive
What is a key symptom produced by vibrio cholera?
Profuse watery diarrhea (10-20 liters per day)
“Rice water diarrhea”
What kind of environment does vibrio cholera grow in?
Grows in alkaline environments
whats the deal with vibrio cholera and acidity?
It is acid labile, dies with acid
How is vibrio cholera transmitted?
Cholera is transmitted fecal oral due to poor sanitation that gets into food and is not an invasinve infection.
Where does vibrio cholera hide in our body?
Found in the intestines and is found in the intestinal mucosae
TEST QUESTION:
Describe the pathogenesis of vibrio cholera.
Attaches to the mucosa by fimbriae that attach to ganglioside receptors in the intestinal wall.
Then releases cholera toxin - Main Virulence Factor AB type toxin
a. Upregulates production of Gαs cAMP by binding to and increasing activating adenylate cyclase.
b. Then it will activate the GS pathway. Activates GS, upregulates cAMP, Produces watery diarrhea through an efflux if Cl and H2O
How does vibrio cholera infect the mucosa?
Does NOT invade mucosa, it uses fimbriae to attach to ganglioside receptor in the intestinal wall.
What is the TXT for a vibrio cholera infection?
Drinking some water - Oral rehydration therapy with electrolytes
What type of toxin is the cholera toxin?
Main Virulence Factor: AB type toxin
Vibrio Vulnificus and Vibrio paraliticus contaminates what types of food?
Can contaminate seafood, especially oysters
Main symptom of Vibrio Vulnificus?
Acute gastroenteritis
Main symptom of Vibrio paraliticus?
Fulminating septicemia leading to death.
Marked edema and necrosis
BORDETELLA PERTUSSIS
“Board and Care”
BORDETELLA PERTUSSIS
“Board and Care”
How does Bordetella pertussis spread?
Respiratory droplets
How does the bordetella pertussis cause infection?
attaches to respiratory epithelium using pili and once attached, rather than invading, it releases toxins that cause systemic effects.
What is the name of the pilis of the Bordetella pertussis?
Plus called filamentous hemagglutinin
What are the toxin of the bordetella pertussis called?
Pertussis Toxin
Adenyltate cyclase toxin
Traqueal toxin
TEST QUESTION:
How does Pertussis Toxin function?
Pertussis toxin ribosylates Gi thus, disabling it.
Toxic inhibits GI, disabled Gi (G inhibitor protein), Leads to a rise in cAMP.
ADP Disables Chemokine receptors for lymphocytes
leading to an overabundance of white blood cells in the blood stream, lymphocytosis
TEST QUESTION:
How does Adenyltate cyclase toxin function?
Adenylate cyclase toxin acts like the anthracis toxin edema factor, increases cAMP directly,
Edema Factor, Most Virulent
TEST QUESTION:
How does traqueal toxin function?
Tracheal toxin damages ciliated cells in the respiratory epithelium
What is the name of the main disease caused by bordetella pertussis?
Whooping cough
Another name for whooping cough?
100 day cough
What are the three stages of whooping cough?
Catarrhal stage
Paroxysmal stage
Convalescent stage
TEST QUESTION:
Describe the Catarrhal stage
Non specific symptoms
Most contagious
lasts 1 - 2 weeks
characterized by symptoms of an upper respiratory infection such as low-grade fever, nasal congestion and rhinorrreal
TEST QUESTION:
Describe the Paroxysmal stage
Lasts 2-8 weeks
Characterized by paroxysms of coughing followed by an inspiratory whoop.
Characteristic cough “whoop”
TEST QUESTION:
Describe the Convalescent stage
Lasts weeks to months
Final stage lasting 3 months with a cough, 100 day cough
Most susceptible to secondary infections
What is the TXT for Bordetella pertussis?
Treatment Macrolides
Which vaccines are available For bordetella pertussis?
DTaP - acellular vaccine using purified antigens (given to children with Dipthrea Toxoid, Tetanus toxoids, acellular Pertussis
Killed vaccine - no longer used in USA
Gram type of Bordetella Pertussis?
Negative
Bordetella pertussis aerobic or anaerobic?
aerobic
How does bordetella pertussis move around?
It doesnts since its non-motile
HAEMOPHILUS INFLUENZAE
“Phyllis’s Chocolate Covered Cherries”
HAEMOPHILUS INFLUENZAE
“Phyllis’s Chocolate Covered Cherries”
Gram type of haemophilus Influenzae?
Gram negative bacteria
Shape of Haemophilus Influenzae?
Coccobacillary shape
In what type of agar is haemophilus influenzae grown in?
Chocolate agar + factor 5 (NAD, nicotinamide) + factor 10 (hemodin)
What factor 5?
NAD (Nicotinamide Adenine Dinucleaotide) which needs to be added to the chocolate agar
Whats Factor 10?
hemodin which needs to be added to the chocolate agar
Haemophilus influenzae is primarily moved by what kind of transmission?
Aerosol transmission leading to droplets going to the respiratory tract calling pneumonia
What is one of the most high yield manifestation of Haemophilus influenzae infection?
Epiglottitis - symptoms Drooling, inflamed epiglottis, inspiratory strider, drooling
“cherry red epiglottis”
As far as USMLE is concerned, epiglottis is caused by haemophilus influenzae
Who is mostly affected by Haemophilus influenzae?
children
Haemophilus influenzae also causes what?
otitis media (inflammation of middle ear) and meningitides
What does haemophilus influenza need to cause meningitides?
Only caused by type B capsular form
Patient without a spleen gets infected with haemophilus Influenzae, what would happen?
Sepsis and Septic arthritis in patients without a spleen (spleenectomized patients), hemophilic
infections, especially sickle cell disease
Since spleen is required to remove encapsulated organisms just like strep. pneumo
There is a haemophilus influenza vaccine. Talk about it.
Vaccine for only the type B capsule is
conjugated with diphtheria toxoid and haemophilus type B capsule so it can prevent meningitis.
Almost all eradicated in USA.
When is the most appropriate time to vaccinate a child with haemophilus influenza vaccine?
Vaccinate between 6 weeks - 18 months (polysaccharide conjugated to diphtheria toxid)
What is the treatment for a Haemophilus influenza infection?
Ceftriaxone
What is the TXT for close contacts with someone with a Haemophilus influenza infection?
Rifampin
LEGIONELLA
“The SS cysteine joins the legion”
LEGIONELLA
“The SS cysteine joins the legion”
Gram type of Legionella?
Gram negative but hard to visualize it so it needs something “special”
What is necessary to visualize legionella?
silver strain to visualize
What is the agar requirement of legionella?
Buffered Charcoal yeast extract in presence of cysteine and iron
What is needed to be added to the agar to legionella?
Cysteine and iron need to be added to agar
What kind of fevers can you get from legionella?
Pontiac Fever
Legionnaire’s Disease
Describe Legionnaire’s Disease.
Atypical pneumonia patchy unilobed infiltrate
Common in smokers and elderly men.
More serious than pontiac fever
What are the other atypical pneumonias?
Atypical pneumonia” is atypical in that it is caused by atypical organisms (other than Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis).
These atypical organisms include special bacteria, viruses, fungi, and protozoa. In addition, this form of pneumonia is atypical in presentation with only moderate amounts of sputum, no consolidation, only small increases in white cell counts, and no alveolar exudate.
At the time that atypical pneumonia was first described, organisms like Mycoplasma, Chlamydophila, and Legionella were not yet recognized as bacteria and instead considered viruses. Hence “atypical pneumonia” was also called “non-bacterial”
In a question stem showing the lab results from a patient’s blood test, what should you look for?
Hyponatremia - excess HNO3 ammonia Na.
Look at sodium metabolic panel, If sodium is <130 (hyponatremia), smoker, headache, confusion, diahrrea, pneumonia, High fever over 104 F (40 C)
Which lab test can be used to confirm a legionella infection?
rapid urine antigen test to confirm
What is the TXT of a legionella infection?
Treat with macrolides and fluoroquinolones
Legionella is oxidase positive or negative?
Oxidase Positive
What is the main virulence factor of legionella and how does it work?
Zinc Melloprotease is the main virulence factor, its cytotoxic and inhibits PMN production,
inhibits superoxide reduction, deactivates il-1 and CD4 and TNF.
BRUCELLA
Bruce Farms
BRUCELLA
Bruce Farms
Gram type of brucella?
Gram negative
Who or what can be a reservoir for brucella?
cows and pigs, goats, veterinarian, slaughterhouse worker, or rancher.
How might one get infected with brucella?
Indirect contact with milk or cheese products that unpasteurized
What kind of bacteria is brucella?
zoonotic
Brucella bordis comes from which animal?
cow
What are the initial symptoms of brucella?
Undulant fever (fever rises and falls)
Chills
anorexia
Chronic infection can lead to what complication?
osteomyelitis
What is the TXT of brucella?
tetracycline such as doxycycline along with rifampin as adjunctive therapy (blocks oxidative burst)
TEST QUESTION:
Which cells are affected by brucella?
macrophages
TEST QUESTION:
How is brucella protected from a respiratory burst?
Large amounts of catalase and superoxide dismutase to protect from respiratory burst
TEST QUESTION:
Which tests are positive for brucella?
Urease positve
H2S positive
TEST QUESTION:
What does brucella require to grow?
CO2
TEST QUESTION:
Where does brucella live in?
acultative intracellular can live inside or outside of host cells ability to survive in macrophages makes it apt to travel reticular and endothelial system.
TEST QUESTION:
What happens when brucella replicates inside a human cell?
Can then replicate intracellularly to the point of causing host cell lysis and then spread systemically.
TEST QUESTION:
What happens once brucella spreads in the body?
Since it can spread reticular endothelial organs, it will lead to enlargement of spleen, liver, and lymph nodes.
FRANCISELLA TULARENSIS
“Francis the Rabbit”
FRANCISELLA TULARENSIS
“Francis the Rabbit”
What kind of bacteria is francisella tularensis?
zoonotic bacteria
Gram type of grancisella tularensis?
Gram negative
Shape of francisella telarensis?
Coccobaccilli
How does francisella telarensis spread?
Tick vector or rabbit vector
What is the name of the rabbit vector of francisella telarensis?
Dermacenter tick
If you get a patient with francisella telarensis infection inside USA, what do you have to do and why?
Contact CDC since it Can be aerosolized and potential to use in bioterrorism
Where does the francisella telarensis bacteria chill?
Facultative intracellular - cell mediated immunity needed to kill it
What is the main symptom of francisella telarensis?
Causes painful ulcer
TEST QUESTION:
Describe pathogenicity of francisella telarensis.
Enters through ulcer and into macrophages in the lymph system to reticuloendothelial organs and causes caseation necrosis
In a physical examination of a patient with francisella telarensis, what might you find?
Regional lymphadenopathy
ulcer
What is the TXT of francisella telarensis infection?
aminoglycoside (streptomycin)
Why does francisella telarensis induce oxidative burst?
Fransciella does not induce oxidative burst
COXIELLA BURNETII
“Curly Q the Ram”
COXIELLA BURNETII
“Curly Q the Ram”
What is the main disease caused by coxiella burnetti?
Q fever
Gram type of coxiella burnetti?
Gram negative
What kind of rash does coxiella burnetti cause?
coxiella does not cause a rash, IE NO RASH
What kind of organism is coxiella burnetti?
Obligate intracellular organism
zoonotic organism
How is coxiella burnetti transmitted?
transmission - spore like structure that comes in animal droppings after it survives the digestive tract of animals
How does coxiella burnetti infect humans?
It gets into humans through aerosol transmission -
outbreaks from farm animals to farmers or placental excretions
Clinical presentation of coxiella burnetti?
Pneumonia
headache
fever
What is a complication of coxiella burnetti?
hepatitis
What antibiotics should be given to a patient with coxiella burnetti infection?
Antibiotics are not needed, self-limiting
How is coxiella burnetti prevented?
Prevention is pasteurization of milk
TEST QUESTION:
Literally test will give a case of: patient with pneumonia, hepatitis, and in the context of being around animals you should think:
Coxiella burnetti and Brucella
But how can you differentiate both?
Brucella has undulating fever while coxiella burnetti does not.
A patient with chronic Q fever can develop what?
endocarditis especially if they are immunocompromised or have previous valvular damage
How long does a Coxiella burnetti infection usually last?
2 weeks
in a physical examination of a patient with Coxiella burnetti infection, what can you find?
Hemorrhage on fingers
PASTUERELLA MULTOCIDIDA
“Louis Pasteur’s Lab”
PASTUERELLA MULTOCIDIDA
“Louis Pasteur’s Lab”
Gram type of pastuerella multocidida?
Gram negative
where is pastuerella multocidida found in?
respiratory tract of small mammals especially Dog and cats.
How is pastuerella multocidida transmitted to humans?
Dog and cat bites
What happens after a patient is bitten from an animal with pastuerella multocidida infection?
Red erythematous that happens immediately - Leads to a cellulitis after a bite
Within first 24 hours
What are some of the complications of a pastuerella multocidida infection?
May lead to a necrotizing fasciitis or osteomyelitis
Which patients can get the worst complications of a pastuerella multocidida infection?
Lymphadenopathy in patients with COPD or Liver disease
Which tests are positive for pastuerella multocidida?
Catalase positive
Oxidase positive
What is an important virulence factor?
Capsule
On which agar does pastuerella multocidida grow on?
Grows on 5% sheep’s blood agar
When observed under microscope, what does pastuerella multocidida look like and what does it resemble?
Bipolar / safety pin staining similar to Yersinia
What is the TXT for pastuerella multocidida?
Emperic treatment is: penicillin
In addition, you might want to use Beta Lactamase inhibitor to avoid resistance such as: amoxicillin and clavulanic acid
BARTONELLA HENSEALE
“Bart the Leopard”
BARTONELLA HENSEALE
“Bart the Leopard”
Gram type of Bartonella henselae?
Gram negative but needs something “special”
What is required to visualize Bartonella henselae?
Wartharin Starry silver Stain
What diseases can be caused by Bartonella henselae?
Cat scratch fever or disease
Bacillary angiomatosis
What happens if an immunocompromised patient gets infected with a Bartonella henselae?
Bacillary angiomatosis is transmitted by cat scratches to Immunocompromised individuals
What happens if an immunocompetent patient gets infected with a Bartonella henselae?
Cat scratch fever: Fever and can involve regional lymph nodes in axilla in one arm, this happens in immunocompetent patient
This causes painful and large lymph nodes in axilla.
Of the two Bartonella henselae diseases, which type of patient gets what?
immunocompetent - cat scratch fever
immunocompromised - Bacillary angiomatosis
What is the main symptom of a Bartonella henselae infection in a immunocompromised patient?
Raised red vascular lesions in Bacillary angiomatosis all over the skin in Immunocompromised individuals (commonly HIV patients)
What is the differential and very similar to Bacillary angiomatosis?
Karposi’s sarcoma is very similar and is a differential
Both have red vascular lesions on skin and happen in immunocompromised patients.
How can you differentiate Karposi’s sarcoma and bacillary angiomatosis?
Skin biopsy or Wartharin starry silver stain
What is the TXT for Bacillary angiomatosis?
Doxycycline or macrolide like azithromycin
What is the TXT for cat scratch fever?
Usually self limiting but if there is swelling and pain and becomes severe you can use a macrolide like azithromycin
NOCARDIA ASTEROIDES
No Card Game for Old men
NOCARDIA ASTEROIDES
No Card Game for Old men
Gram type of Nocardia asteroides?
Gram positive
Shape of nocardia asteroides?
Branching filamentous Rods
What tests are positive for norcardia asteroides?
Urease positive
Catalase positive
What does nocardia asteroides need to survive?
Obligate aerobe
TEST QUESTION:
Which type of patient has an increased risk of nocardia asteroides infection?
Primarily affects Immunocompromised vulnerable especially those with impaired cell mediated immunity
Includes HIV, transplant patients or patients taking glucocorticoids
CGD patients have increased risk (Catalase positive)
where is nocardia mainly found in?
Found in soil
What kind of spores nocardia form?
Nocardia does NOT form spores as opposed to tetani and perfringens
Although nocardia is gram positive, it weakly stains what?
Partially stains Acid Fast, which is carbofusion stain that stains mycolic acids in its cell wall (long chains with two tails)
Gender wise, who is more at risk of nocardia infection?
men > women
What are the three main sites of nocardia infections?
Pulmonary (pulmonary nocardiosis)
CNS
cutaneous (Cutaneous nocardiosis)
Nocardia has an affinity to what kind of tissue and what is a complication it can cause from it?
CNS; Brain abscess formation
What are the symptoms of pulmonary nocardiosis?
Pneumonia with lung abscess formation like symptoms, cavitary lesions in the lung
What are the symptoms of cutaneous norcadriosis?
pyogenic response ensues that leads to indurated lesions and inflammatory reaction
What is the treatment for nocardia infection?
Sulfonamides
ACTINOMYCES ISRAAELII
“Israeli Soldier”
ACTINOMYCES ISRAAELII
“Israeli Soldier”
Gram type of actinomyces israaelii?
Gram positive
Shape of actinomyces israaelii?
Branching filamentous rods
What does actinomyces israaelii need to survive?
Obligate anaerobe
What is the main disease caused by actinomyces israaelii?
Cervical facies actinomyces infection
TEST QUESTION:
Describe the course of a Cervical facies actinomyces infection
Slow course
Non tender lump on jaw
Forms abscess
Formation of sinus tract that drain the infection site through the skin
Thick yellow pus is formed since it forms thick yellow sulfur granules
How is a patient infected with actinomyces israaelii?
Infection associated with jaw trauma due to the fact that actinomyces israeli is part of the normal flora of oral cavity
recent dental work
How can you differentiate actinomyces israaelii and nocardia?
actinomyces israaelii = Obligate anaerobe
Nocardia = obligate aerobe
What is the TXT of actinomyces israaelii?
penicillin G
More complicated courses: surgical drainage may also be warranted
CHLAMYDIA TRACHOMATIS
CHLAMYDIA PNEUMONIA
CHLAMYDIA PHILAPSITTACI
“The pirates of Calam Island”
CHLAMYDIA TRACHOMATIS
CHLAMYDIA PNEUMONIA
CHLAMYDIA PHILAPSITTACI
“The pirates of Calam Island”
What kind of gram type is Chlamydia?
Gram intermediate - does NOT gram stain
What kind of bacteria is chlamydia?
Obligate intracellular bacteria
Why is chlamydia obligate intracellular bacteria?
Cannot create its own ATP which is why it is intracellular
The wall of chlamydia lacks what?
It lacks muramic acid that is found in the cell walls of most other bacteria.
This makes Chlamydia resistant to betalactam antibiotics such as penicillin, because such antibiotics disrupt the “typical” cell wall, which includes muramic acid.
How is the cycle of chlamydia divided into?
Elementary stage
Reticular Body
Release of these newly divided cells (in elementary stage again)
What is the 1st stage of of life cycle of chlamydia?
1st stage of life cycle outside of the cell aka “elementary stage”
This is the INFECTIOUS form.
Elementary enters the eukaryotic cell and are taken up by phagosomes.
“ELEMENTARY ENTERS”
What is the 2nd stage of of life cycle of chlamydia?
2nd stage: “reticular body”
and is ACTIVE form and multiply, aka the DIVIDING form.
Reticular Replicates to form Inclusion Bodies seen under
microscope in cells when infected.
“RETICULATE REPLICATES”
Under a microscope, what do you see when you’re looking at chlamydia?
Inclusion bodies seen when under a microscope in cells infected with chlamydia.
Inclusion bodies = bunch of reticulate bodies which are diving in the cell.
What is the stain needed when visualizing Chlamydia?
Giemsa Stain since chlamydia cant be gram stained.
How can you diagnose chlamydia?
NAAT Test (NAAT is just fancy word for PCR)
Nucleic Acid Amplification Test = NAAT
Describe pathogenicity Reiter’s syndrome.
Maladaptive autoamune response.
The body fighting the bacteria makes antibodies that cross react and attack the body.
It has a triad of symptoms.
What is the the Triad of symptoms Reiter’s syndrome?
Reactive arthritis
Uveititis
Urethritis
“can’t see, cant pee, cant climb a tree”
Where does the reactive arthritis of Reiter’s syndrome presents itself on?
Sacroiliac joint and the knee but several other locations it can be presented.
What are the three types of chlamydia?
Chlamydia trachomatis
Chlamydia pneumoniae (also known as Chlamydophila pneumoniae)
Chlamydia psittacci.
How is chlamydia trachomatis divided into groups?
A-C: blindness
D-K: STI
L1-L3: LGV
What is the Most common Bacterial STI in US?
chlamydia trachomatis D-K: STI2
Describe chlamydia trachomatis D-K: STI.
Most common Bacterial STI in US
Can even remain asymptomatic.
Characterized by Watery discharge, while Ghonorrhea has a mucopurulent discharge.
Can turn into PID in women w/o symptoms.
Ectopic pregnancies as well
Describe PID.
Ascending infection.
Can lead to cervicitis, salpingitis, pelvic pain, abscess formation, scarring of the tubes that can cause infertility and ectopic pregnancies later in life.
What can happen if a mother has chlamydia trachomatis D-K: STI during delivery?
Baby can get infection if mother has it during delivery giving it neonatal conjunctivitis and neonatal pneumonia.
How can you differentiate if the baby got chlamydia or gonorrhea infection during birth?
The key is the Time Frame!!!!!
Chlamydia: Baby will present within 1-2 weeks with a possible cough (pneumonia) or conjunctivitis.
Gonorrhea will present 2-4 days (short time frame)
BUZZWORD:
How can you tell if a neonatal has pneumonia?
Staccato cough which is a really short sudden burst
What does chlamydia trachomatis L1-L3 cause in disease?
Lymphogranuloma Venereum (LGV)
How is Lymphogranuloma Venereum (LGV) characterized?
Tender Inguinal lymphadenopathy
What is Lymphogranuloma Venereum (LGV)?
Infection of the inguinal nodes
Presents as a tender lymphadenopathy with draining lymph nodes.
Caused by chlamydia trachomatis L1-L3
sexually transmitted bacterial infection
It is caused by any of 3 different types (serovars) of the bacteria Chlamydia trachomatis.
The infection is not caused by the same bacteria that cause genital chlamydia.
What it the leading cause of blindness of the worldwide?
trachoma
Which type of chlamydia is related to blindness?
chlamydia trachomatis A-C
How is chlamydia trachomatis A-C transmitted?
Hand to Eye contact, or formats
What is the main disease caused by chlamydia pneumonia?
walking pneumonia or “seeing pneumonia”
its Atypical pneumonia (just like mycoplasma and legionella)
Who are most likely affected by chlamydia pneumoniae?
More common on elderly as opposed to young adults
How is Chlamydia Psittaci transmitted and which disease does it cause?
Transmitted by Birds, causes pneumonia and transmitted by bird droppings
TEST QUESTION UWORLD EVERYWHERE!!!!!!
What is the WRONG treatment for chlamydia?
and what is the RIGHT empiric treatment?
WRONG TREATMENT:
- Macrolide (azithromycin)
- Tetracycline (such as doxycycline)
RIGHT TREATMENT:
Confection of Chlamydia and gonorrhea treat with
azithromycin + cephtriaxone
TEST QUESTION UWORLD EVERYWHERE!!!!!!
What is the treatment for gonorrhea?
RIGHT TREATMENT:
Confection of Chlamydia and gonorrhea treat with
azithromycin + cephtriaxone
TXT for Atypical pneumonia caused by chlamydia pneumonia?
1st line: Tetracycline (such as doxycycline)
2nd line: Macrolide (such as azithromycin)
GARDNERELLA VAGINALIS
“The Fish Garden”
GARDNERELLA VAGINALIS
“The Fish Garden”
What is the main buzzword of gardnerella vaginalis?
Fish odor
Gram type gardnerella vaginalis?
Gram variable (can stain gram positive or gram negative)
Shape of gardnerella vaginalis?
Rod
What is the normal flora of the vagina?
Lactic bacilli
What can get rid of the normal flora of the vagina?
Normal vaginal flora is lactic bacilli, an overgrowth of anaerobic flora will get disrupt the normal flora of vagina.
What is the main symptom of gardnerella vaginalis?
Thin grayish white malodorous odorous discharge from the vagina.
Fishy smell.
What is the main disease caused by gardnerella vaginalis?
Bacterial Vaginosis
When does gardnerella vaginalis occur?
The discharge caused by bacterial vaginosis pH > 4.5 (usually pH is between 5.0 - 6.5) is when infection occurs
How can you diagnose Bacterial Vaginosis?
Positive Whiff test w/ 10% KOH prep
or microscopic exam
Describe the diagnostic microscopic exam for Bacterial Vaginosis?
wet mount preparation of bacterial vaginosis discharge shows these characteristic Clue cells which are epithelial cells diffusely coated with bacteria.
What is the TXT for Bacterial Vaginosis?
Metronidazole
What are clue cells?
Clue cells which are epithelial cells diffusely coated with bacteria.
MYCOPLASMA PNEUMONIAE
“Walking on Thin Ice”
MYCOPLASMA PNEUMONIAE
“Walking on Thin Ice”
Gram type of mycoplasma pneumoniae?
Gram indeterminate since it has no cell wall
What so special about the anatomy of mycoplasma pneumoniae?
cell membrane with cholesterol (only bacteria that has it)
Sterols stabilize cell membrane but also allows it to be more flexible
What is the main disease caused by mycoplasma pneumoniae?
Walking pneumoniae
Why is it called “Atypical pneumoniae”?
Atypical pneumonia because you cant readily culture a microbe
Why is it called “Walking pneumoniae”?
patients have X ray much worse than patients appear sick clinically that bad and they can even be walking around.
What would you see in an X-ray of Walking pneumoniae?
Patchy infiltrate in x ray
Who are more at risk of mycoplasma pneumoniae?
Young adults, commonly in military recruits living in close quarters
< than 30 year olds
Which agar is used for mycoplasma pneumoniae?
Grown on eatons agar (takes about a week)
TEST QUESTION: HIGH YIELD:
On a cellular level what happens during a mycoplasma pneumoniae infection?
About 1 or 2 weeks into a mycoplasma pneumonia infection, people may develop IgM molecules that agglutinate (clumping) RBC in cold temperatures (4 C).
Leads to lysis RBC.
This is called cold agglutinates.
Present in only 50-70%.
What is the TXT of mycoplasma pneumoniae?
Macrolide (azithromycin) since it has no cell wall.
RICKETSSIA SPECIES
Rickettsia Tennis
RICKETSSIA SPECIES
Rickettsia Tennis
Rickettsia gram type?
Gram negative but don’t gram stain well aka Pleomorphic
What kind of cell is Rickettsia?
Obligate intracellular
What is the pathogenesis of Rickettsia?
Colonize endothelial cells and cause endothelial hyperplasia
Why is Rickettsia is obligate intracellular?
Unable to produce NAD+ and CoA (which are energetic compounds) so they get it from eukaryotic cells.
Both are important for bacterial growth and replication.
Shape of Rickettsia?
Coccobacillary shape that are weakly gram negative
shaped Somewhere between cocci and bacilli
Which test can be sued to diagnose rickettsia?
Weil Felix agglutination test for rickettsia infections
What are some of the symptoms of rickettsia?
Prodromal headache and fever in early rickettsia, along with vasculitis, a rash may be associtated
What are the main symptom of rickettsia?
Vasculitis
Inflammation and destruction of blood vessels
What is the TXT of rickettsia?
Doxycycline
Supportive care with vascular collapse.
What is the TXT of a preggo with rickettsia?
Chloramphenicol
RICKETTSIA PROWAZEKKI
“Pro Boot Camp”
RICKETTSIA PROWAZEKKI
“Pro Boot Camp”
What kind of cell is Rickettsia prowazekki and its gram type?
Obligate intracelular - poor gram staining
What is needed for Rickettsia Prowazekki to survive and grow?
NAD+ and CoA needed
What is the treatment for Rickettsia Prowazekki?
Doxycycline treatment
What are the symptoms of Rickettsia Prowazekki?
Myalgia and arthralgia Pneumonia Encephalitis with dizziness and confusion Coma (if really serious) Unremitting headache Patchy rash that begins on the region
What is the first symptom of Rickettsia Prowazekki?
Rash starts at trunk and moves toward the extremities, Rash spares the hands, feet, and head
Who are more at risk of rickettsia Prowazekki?
Affects military recruits and POW’s , close contact allows for human to human spread
How does Rickettsia Prowazekki spread?
Lice spread prowazeki, Louse feeds on blood and deaths near deeding sites
What is the pathogenicity of Rickettsia Prowazekki?
Lice spread prowazeki, Louse feeds on blood and deaths near deeding sites
Scratching that infects from patients from the lice feces since it gets itchy on skin.
What is the illness called cause by Rickettsia Prowazekki?
Illness is called epidemic typhys: widespread outbreak
What is the difference between epidemic typhus and endemic typhus?
Epidemic typhus: rickettsia Prowazekki (desease thats widespread outbreak)
Endemic typhus: Rickettsia typhi (diasese localized to a region)
RICKETTSIA RICKETTSII
“Rickett’s Rock Climbing Competition in the Dermacenter arena”
RICKETTSIA RICKETTSII
“Rickett’s Rock Climbing Competition in the Dermacenter arena”
Rickettsia Rickettsii gram type?
Obligate intracellular - poor staining (lack of gram staining)
Which stain can be used to vizuale rickettsia rickettsii?
Giemsa Stain
What does rickettsia rickettsii need for growth and replication?
CoA and NAD+ are needed for growth and replication and is provided by the host
TXT for rickettsia rickettsii?
Doxycycline
How is rickettsia ricketsii transmitted?
Transmitted via ticks
Dermacenter Tick transmission through direct biting
What is the incubation period of rickettsia ricketsii infection?
Incubation period of 2-14 days
Describe the rash that is characteristic of a ricketsia ricketsii infection.
Causes a maculopapular rash that starts on ankles and wrist, then moves more centrally
Rash spreads extremities to centrally.
Describe the symptomatology of rickettsia ricketssii infection.
Headache, severe fever, and muscle pains (myalgia)
MYCOBACTERIUM TUBERCULOSIS
“Shootout at the TB corral”
MYCOBACTERIUM TUBERCULOSIS
“Shootout at the TB corral”
How does mycobacterium tuberculosis stain?
Stains Acid fast which is represented by mycelia acids (Carbol fuschein stain)
mycobacterium tuberculosis is obligate ______.
Obligate aerobe
In which medium does mycobacterium tuberculosis grow on?
Lowenstein Medium
Takes 2-6 weeks
Describe the transmission of mycobacterium tuberculosis
Transmission is human to human respiratory droplets
Where does mycobacterium tuberculosis proliferate in?
Macrophage cage
What is the virulence factor of mycobacterium tuberculosis.
Virulence factor is called cord factor.
Cell wall contains glycolipids which are responsible for clumping of bacteria into a serpentine formation.
What is the function of the Cord factor?
Cord factor role is protection of bacteria from being destroyed.
Cord factor will Increases granuloma formation by increasing TNF-a activating other macrophages walling
itself off in a granuloma - this will protect the bacteria HOWEVER, it cant spread anymore
So: cord factor increases immune response (so it cant spread anymore) but protects the bacteria from walled off inside a granuloma which is created by the new activated macrophages.
What allows TB to survive inside cells like macrophages?
Sulfatides - prevent phagolysosome fusion thus, sparing the microbe to lysosomal hydrolazes.
Allow TB to survive in macrophages by creating incompetent secondary lysosomes preventing fusion to hydrolyzes which are unable to fuse.
What are the paths of progression after primary infection?
- Healed latent infection
- Systemic infection (Miliary TB)
- Reactivation of latent TB (infection was once latent but reactivates later in life)
Describe Primary infection of TB.
Affects the Lungs (primarily either lower or middle lungs)
Forms the GHON complex.
Describe the GHON complex.
Can occur during primary infection of TB.
After infections heals, lesion becomes fibrotic and eventually calcifies as do the nearby lymphnodes.
They are visible calcification of lung parenchyma and Heal lymph nodes that can be seen on Chest X rays.
GHON complex = Hiliar lymphadenopathy + peripheral granulomatous lesion in middle or lower lung lobe.
What kind of necrosis forms from mycobacterium tuberculosis ifnection and why that kind of necrosis?
Characterized by a collection of activated macrophages (called Langerhans giant cells) and in the case of TB it is Caeseation necrosis that can cause fibrosis and scarring.
Formed in attempt to wall off an area of infection.
Why is it called TUBERculosis?
Caseation Granulomas = tubers
Tuberculosis resides in broken down necrotic macrophages (Langerhans giant cells)
What are Primary infection symptoms of mycobacterium uberculosis?
prolong fever and most commonly in children in areas that are endemic of TB.
Most cases of primary infection resolve and healed by fibrosis and calcification and become latent.
How does primary infection of mycobacterium resolve?
Resolves by fibrosis and become latent (hibernates)
How can you test for a mycobacterium tuberculosis.
Test for TB with PPD on skin
What another name for PPD?
The tuberculosis skin test is also known as the tuberculin test or PPD test.
How can you prevent a mycobacterium tuberculosis infection?
BCG vaccine is attenuated from mycobacterium Bovis.
Will always show positive skin test
Will show positive regardless if its active, latent or if patient received BCG vaccine.
How effective is the BCG vaccine?
Effectiveness ranges from 0 - 80%
Describe the Millciary TB.
Multi-organ failure (commonly affects bone, liver and lymphatics)
Potentially Lethal
Especially affects Immigrants from endemic areas.
Describe Reactivation of latent TB.
Associated with immunosuppression (HIV, cancer, Old people) through down regulation of TNF alpha release (TNF alpha is a proinflamatory cytokine that causes infection to be contained but if its neutralized, then infection would spread again).
Reactivation is on the upper lungs, look for cough, night sweats, bloody cough (hemoptysis).
Only occurs in 5-10% of people
Describe the mechanism of which immunosuppression causes reactivation.
Associated with immunosuppression through downregulation of TNF-a release (which is a proinflamatory cytokine that causes the infection to be contained). Therefore, if it is neutralized then the infection will spread again.
Immune system is defenseless if TNF is inhibited.
What should you always do before using a TNF inhibitor?
Always screen for PPD before using a TNF inhibitor like infliximab to make sure youre not putting them at risk for reactivation of TB
What are the 3 classic symptoms of reactivation of TB?
cough, night sweats, bloody cough (hemoptysis), cachexia
Once TB reactivates, where does it primarily affects in the lungs?
When TB reactivates, it primarily affects upper lobes as opposed to middle and lower lobes during a primary infection.
What other organ systems can TB affect?
Skeletal system and the CNS
What is the disease called when TB affects the bones?
Pott’s disease is when TB has affected the spinal column.
Usually multiple vertebrae are affected.
demineralization of the bone with soft tissue pain which causes pain and can progress to abscess formation, spinal deformities and weakness.
If TB affects the CNS, what can you expect?
CNS involvement can manifest as meningitis or tuberculoma (which is a cavitary lesion of the brain).
10-15% in patients with reactivation of TB
What is the treatment for TB?
Combination of RIPE:
Rifampin
Isoniazid
Pyrazinamide
Ethambutol
What is the prophylaxis of TB?
Prophylaxis:
Rifampin or isoniazid - 9 months
MYCOBACTERIUM LEPRAE
“The Good, the Bad and the Lion Faced”
MYCOBACTERIUM LEPRAE
“The Good, the Bad and the Lion Faced”
In what kind of environment does mycobacterium leprae thrive in?
Thrives in cool temperatures, explaining predilection for extremities
Where does mycobacterium leprae like to affect our bodies?
prevalence of growth in extremities
What kind of stain is used on mycobacterium leprae?
Acid fast bacteria (carbol fuscion stain)
What takes up the acid fast stain?
Mycolic acids
What is the major reservoir of mycobacterium leprae?
Armadillos are the major reservoir
What is another name for leprocy?
commonly called Hanson’s Disease
What are the two presentations of Hanson’s disease?
Tuberculoid
Lepromatous
Describe the Tuberculoid presentation.
Helper TH1 cells stimulate macrophages to engulf the bacteria in cell mediated immunity.
Tuberculin response: able to contain bacteria within macrophages.
Mild symptoms, well demarcated hairless lesions on skin (can occur anywhere in the body)
What kind of test can you do for the Tuberculoid leprocy presentation of mycobacterium leprae?
Lepermans skin test - test for immune reaction, similar to TB Test, wheel will form if positive
It is an interdermal injection of bacterial antigen to test for presence of immune reaction (just like TB)
What does a positive lepromin skin test mean?
Positive Lepromin skin test demonstrates good cell mediated response.
Describe the lepromatous prevention of mycobacterium leprae.
“classic leoprasy”
TH2 cells promote humoral (humorous) response
Bacteria being unable to contained in macrophages
How is lepromatous leprocy is transmitted?
High chance of transmission human to human
Via respiratory droplets? Exact mode of transmission isn’t known
Describe what lepromatous leprocy does to the human body.
Distal portions (its cooler in temperature) are affected in a symmetric glove and stocking pattern.
Numerous extensor surfaces are cooler and present with disease of demarcated raised lesions (can occur anywhere in body but most notably on extensor surfaces of extremities).
What is the main clinical manifestation of lepromatous leprocy?
“Leonine faces” (since it makes the look like they have the face of a lion)
Causes profound facial deformity.
Thickening of the skin, loss of eyebrows and eye lashes, collapse of the nose and formation of nodular earlobes.
What is the TXT for TH1 dominant infection?
multi drug therapy for long time
TH1 dominant infection: Dapsone and rifampin for 6 months
What is the TXT for TH2 dominant infection?
TH2 dominant infection: Dapsone, rifampfin, and Clofazimine for 2-5 years
BORRELIA BURGDORFERI
“the Bows and Arrows of Borrelia”
BORRELIA BURGDORFERI
“the Bows and Arrows of Borrelia”
Shape of Borrelia Burgdorferi?
Helical and longer than Treponema
Disease that Borrelia Burgdorferi causes?
Causes Lyme disease
Primary geography of Lyme’s disease?
Primarily in the northeastern united states.
New Hampshire and Connecticut
What is the vector of Lyme’s disease?
Transmitted by ticks, Ixodes scapularis.
What are the three diseases that Ixodes scapularis transmits?
Lyme disease
erliciosis (bacterial disease)
bubesiosis (protozoan disease)
Describe the life cycle of the Ixodes scapularis
Mouse - ticks larvae feed on white footed mouse, Main reservoir
Deer - adult form feeds on white tailed deer, Obligatory Host
Tick is the vector, humans are an incidental host
What is the main reservoir of Lyme’s disease?
Main reservoir: White footed mouse
Mouse - ticks larvae feed on White footed mouse
What is the Obligatory Host (Host of Adult Tick) of Lyme’s disease?
Obligatory Host
adult form feeds on White-tailed Deer
Who is the incidental host of Lyme’s disease?
Tick is the vector, humans are an incidental host
Gram stain of Borrelia Burgdorferi?
Spirochetes do not gram stain since they have thin walls
Which stain can be sued to show Borrelia Burgdorferi?
Two stains that can be used, Wright and Giemsa Stain
What is the organism that causes endemic Relapsing fever?
Endemic Relapsing Fever is caused by tick borne borelia hermsii and Borelia duttonii
How many stages of Borrelia?
3 stages
Describe stage 1 of Lyme’s disease.
Hallmark of Lyme’s disease: Erythema Chronic Migrans (“Bulls Eye” rash) Spirochete
Sweating and feverish, flu like illness
Papule will form (Ixodes tick)
When does the Erythema Chronic Migrans (“Bulls Eye” rash) appear?
Usually about a month from tick bite.
Describe stage 2 of Lyme’s disease.
Heart block cause by myocarditis
Bilateral facial nerve Bell’s palsy
Describe Bell’s Palsy.
Bell’s palsy is a condition in which the muscles on one side of your face become weak or paralyzed. It affects only one side of the face at a time, causing it to droop or become stiff on that side.
However, in Lyme’s disease it causes BILATERAL Bell’s Palsy
Describe stage 3 of Lyme’s disease.
Migratory arthritis: Joint pain arthritis of large joints, symptoms may move from joint to joint.
Memory difficulty, cognitive slowing, lymphocytic meningitis.
Suttle encephalopathy
TXT for Lyme’s Disease?
Stage 1 doxycycline
Stage 2 ceftriaxone
TREPONEMA PALLADIUM
“Pallidum Observatory”
TREPONEMA PALLADIUM
“Pallidum Observatory”
What is the shape of Treponema palladium?
Spiral shapes - Spirochetes
In which culture can Treponema palladium grown in?
Treponema palladium cannot be grown in culture, only in rabbit testes
What disease does Treponema Palladium cause?
Syphilis
What is needed for direct visualization of the organism of Treponema Palladium?
Dark field microscopy is needed for direct visualization of the organism.
What is the screening test for Treponema palladium?
Venereal Disease Research Laboratory (VDRL)
blood screening test for Treponema but not specific aka nontreponema specific test
What is the antigen tested in VDRL?
It tests antibody reactivity in patient serum to antigen: cardiolipin-cholesterol-lecithin antigen
What is the RPR test?
RPR - rapid plasmin reagent
Screening tool for syphillisbut high incidence of false positives due to cross antigenicity including:
Mono
Rheumatoid Factor
Lupus
Leprocy
What is the Confirmatory Test of syphillis?
FTA-ABS is a Specific test to confirm a positive screening
Much more specific than VDRL
Describe the stages of Syphillis.
Early stages (occurs during 1st Year):
Primary
Secondary
Early latent
Late stages:
Terciary
Late latent
Congenital syphillus
Clinical presentation of primary syphillis.
Primary: Painless genital chancre.
Syphilis locally invades small blood vessels causing ischemic necrosis and takes out nerves making it painless.
Painless: heals in 3-6 weeks
Clinical presentation of secondary syphillis.
Secondary: Systemic Disease.
Maculopapular rash that occurs on palms and soles of feet weeks to months after infection.
Condoloma Latum on mucous membranes which are a lot of bumps that are flat topped.
How can you visualize the spirochetes in the condoloma latum?
Can visualize the spirochetes in the condoloma lata via dark field microscopy
Clinical presentation of tertiary syphillis.
Tertiary:
- Formations of Gummas which are soft growth with a firm necrotic center. Can appear anywhere including bone, skin, internal organs.
- Aortitis (particularly of the ascending aortic aorta) leading to an ascending thoracic aneurysm.
- Tabes dorsalis
- Argyle Robertson Pupils
What happens to the aorta with syphillis?
Pathologically the aorta demonstrates “Tree barking” which means it will look thick and wrinkled like a tree bark
Syphillis Destroys the vasovasorum or small blood vessels that supply of the aorta.
What is Tabes dorsalis, also known as syphilitic myelopathy?
Demyelination of nerves and posterior walls of the spinal cord and lead to a loss of vibration sense, proprioception and discriminative touch.
This can also accompany lancinating pain all over and a odd gait due to loss of propiocetion.
Describe Argyle Robertson pupil.
Argyle Robertson: Ocular effects that make pupils that accommodate to distance but do not react to light.
“Prostitutes pupil”
Describe Symptoms of Congenital syphillis.
- Saber Shins, an anterior bowing of tibia
- Saddle shaped nose
- Hutchinson Teeth: Notched incisors
- Mulberry molars: Molars will several enamel outgrowths.
- Deafness
What is the TXT of Syphillis?
Penicillin is the treatment In every stage and in everyone
What is the TXT of Syphillis if patient is allergic to the primary treatment?
If allergic - desensitize them and use penicillin
What might occur hours after treatment with penicillin on a patient with syphillis?
Jarisch Herxheimer reaction
Describe the Jarisch Herxheimer reaction.
Jarisch Herschimer reaction is the dying spirochetes releasing a bunch of LPS that cause and increase of cytokines that make people feel sick along with fever and chills.
Within hours of treatment.
Jarisch Herxheimer reaction is good or bad?
Good indicator that the treatment is working.
LEPTOSPIRA INTERROGANS
“The Surfer’s Oasis”
LEPTOSPIRA INTERROGANS
“The Surfer’s Oasis”
What is the shape of leptospirosis interrogans?
Spirochetes may be question marked shaped
leptospirosis interrogans causes what disease?
Leptospirosis or Leptospira
Which is the systemic leptospirosis infection
What kind of region is endemic of leptospirosis interrogans?
Endemic in tropic regions
In USA highest incidence of leptosperirosis is in Hawaii.
Which animals excrete leptospirosis interrogans and how do they do it?
Animals such as Rodents and dogs and is excreted in their urine
How is leptospirosis interrogans transmitted to humans?
Transmitted to humans when swimming in contaminated waters such as during water sports.
Describe clinical presentation of leptospirosis interrogans.
- Flue like symptoms such as Fever and intense headaches.
2. Conjunctival suffusion: redness around the eyes without the puss
What is the most severe form of Leptospirosis?
Weil’s disease
How does the Leptospirosis travel?
travels in blood stream and is able to affect multiple organs.
Which two organs does leptospirosis interrogans like to affect when it is left untreated
Kidney and liver
What are the two most severe complication that can be caused by Leptospirosis?
Renal dysfunction
Jaundice from live damage
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