Micro Bacteria Flashcards
Gram+ Cocci lab algorithm
Cocci --> Catalase test Catalase -: Streptococcus Catalase +: Staph Staph --> Coagulase test Coagulase +: S aureus Coagulase -: Do Novobiocin test "NO StRESs at the staph retreat" Novobiocin sensitive: S epidermidis Novobiocin resistant: S saprophyticus
Gram+ rods
Clostridium (anaerobe) Corynebacterium Listeria Bacillus (aerobe) Mycobacterium (acid fast)
Gram+ with branching filaments
Anaerobe, not acid fast: Actinomyces
Aerobe, acid fast: Nocardia
Streptococcus algorithm
Hemolysis test
Partial hemolysis –> green on blood agar–> α
Complete hemolysis –> clear on blood agar –> β
No hemolysis on blood agar –> γ
α Hemolytic Strep Algorithm
“OVRPS”
Capsule, +Quellung, Optochin sensitive –> Strep pneumoniae
No capsule, Optochin resistant –> Viridans streptococci (S mutans)
β Hemolytic Strep Algorithm
“B-BRAS”
Group A: Bacitracin sensitive –> S pyogenes
Group B: Bacitracin resistent –> S agalactiae
γ Hemolytic Strep Algorithm
Group D (Enterococcus): Growth in bile and 6.5% NaCl (E faecalis) Nonenterococcus: Growth in bile, not 6.5% NaCl (S bovis)
β-Hemolytic Bacteria
Staphlococcus aureus (catalase+, coagulase+) Streptococcus pyogenes (GAS: Catalase-, Bacitracin sensitive) Streptococcus agalactiae (GBS: Catalase-, Bacitracin resistent) Listeria Monocytogenes (tumbling motility, meningitis in newborns, unpasteurized milk)
Staphyloccus aureus
Gram, Shape, Arrangement, Marker
Weapon
Diseases it causes?
Gram+ Cocci in Clusters, Catalase+, Coagulase+
Protein A binds FcIgG and inhibits complement fixation and phagocytosis
TSST –> fever, vomiting, rash, desquamation, shock, end organ failure
Skin infection, Organ abscess (coagulase forms fibrin clot around self), Pneumonia, Endocarditis, Osteomyelitis, Food poisoning (preformed toxins), TSS, Scalded skin syndrome (exfoliative toxin)
MRSA
What is it?
Resistent to…
Methicillin Resistent Staph Aureus
Resistent to β-lactams because of altered penicillin binding protein
Staphylococcus epidermidis
Where is it normally located
Contaminates what?
What does it infect?
Part of normal skin flora
Contaminates blood cultures
Infects prosthetic devices and IV catheters by producing adherent biofilms
Streptococcus pneumoniae Gram, Shape, Arrangement Weapons Markers Most common cause of... Presentation
Gram+, Lancet Shaped, Diplococci
Encapsulated, IgA protease
α hemolytic, Optochin sensitive
“MOPS are Most OPtochin Sensitive”
Meningitis, Otitis media (in children), Pneumonia, Sinusitis
Rusty sputum, sepsis in sickle cell anemia and splenectomy
Viridans Group Streptococci Markers Where are they normally What do they cause? What does it adhere to?
α hemolytic, Optochin Resistent, Produces Dextran from Sucrose
Normal flora of oropharynx
Dental caries (S mutans) and Subacute bacterial endocarditis (S sanguis) - stick to prosthetic valve via glycocalyx
Adheres to Fibrin-Platelet Aggregates
Streptococcus pyogenes Markers Versions w/ diseases Diagnosis Significant protein marker
Gram+ Cocci, β-Hemolytic, bacitracin sensitive
Pyogenic: pharyngitis, cellulitis, impetigo
Toxigenic: scarlet fever, TSLS, Necrotizing fasciitis
Immunologic: Rheumatic fever, acute glomerulonephritis
ASO titers
M protein enhances host defense but gives rise to rheumatic fever
Diagnosis of RF
What causes it?
GAS "JONES" Joints - polyaarthritis Carditis Nodules (subcutaneous) Erythema marginatum Sydenham's chorea
Scarlet Fever Presentation
Scarlet rash sparing face, Strawberry (scarlet) tongue, Scarlet throat
What GAS presentations can lead to other problems?
Pharyngitis –> RF and Glomerulonephritis
Impetigo more commonly precedes glomerulonephritis than pharyngitis
Streptococcus agalacgtiae Markers What does it produce? Colonizes where? What diseases does it cause? In whom? Screen Treatment
“GBS: B is for babies”
Gram+ Cocci, β-Hemolytic, bacitracin resistent, Hippurate test +
Produces CAMP factor which enlarges area of hemolysis formed by S aureus
Vagina
Pneumonia, Meningitis, and Sepsis in babies
Screen pregnant women at 35-37 weeks
Pt’s with + cultures receive intrapartum penicillin prophylaxis
Enterococcus Names Markers Where are they normally? Resistant to? What do they cause? Bad version?
GDS: E. faecalis and E. faecium
Gram+ cocci Non-hemolytic and growth in bile and 6.5% NaCl
Normally in colonic flora
Penicillin G resistent
UTI, Biliary tract infections, Subacute endocarditis
VRE important in nosocomial infection
Lancefield Grouping based on?
Difference in C carbohydrate in cell wall
Streptococcus bovis
Markers
Where does it colonize
What can it cause?
GDS: S bovis
Gram+ cocci Non-hemolytic and growth in bile but not 6.5% NaCl
Colonizes the gut
Bacteremia and subacute endocarditis in colon cancer patients
GDS
S bovis, E. faecalis, E. faecium
Corynebacterium diphtheriae Markers Plating Toxin test? Stains Diseases it causes? How? Symptoms Vaccine
Gram+ rods with metachromatic (blue and red) granules
Black colonies on Cystine-Tellurite agar
Elek’s test for toxins
+ Aniline dyes
Diphtheria via exotoxin encoded by β prophage. Inhibits protein synthesis by ADP-ribosylation of EF2
Pseudomembranous pharyngitis (gray-white membrane), lymphadenopathy, myocarditis, arrhythmias
Toxoid vaccine prevents diphtheria
Spores
What do have in their core?
How do you kill spores?
Dipicolinic acid in the core
Autoclave @ 121 degrees C for 15 minutes
Clostridia
Markers
What do they form?
Types
Gram+ rods that are obligate anaerobes. Spore forming
Tetani, Botulinum, Perfringens, Difficile
Clostridium tetani
Markers
Toxin
Presentation
Gram+ rods that are obligate anaerobes. Spore forming
Tetanospasmin is an exotoxin. Cleaves SNARE protein required for NT release of GABA and Gly neurons (Renshaw cells in spinal cord)
Muscle rigidity, lock jaw, Risus sardonicus
Clostridium botulinum
Markers
Toxin
Presentation
Gram+ rods that are obligate anaerobes. Spore forming
Botulinum toxin
Cleaves SNARE protein required for NT release of ACh from neurons
Baby who ate honey has Flaccid paralysis (floppy baby)
Clostridium perfringens
Markers
Toxin
Presentation
Gram+ rods that are obligate anaerobes. Spore forming
Alpha toxin (lecithinase)
Phospholipase that degrades tissues and cell membranes
Degradation of phospholipid C –> myonecrosis (gas gangrene) and hemolysis (double zone of hemolysis on blood agar)
Gas Gangrenous Leg
Clostridium difficile Markers Toxin Presentation Diagnosis Treatment
Gram+ rods that are obligate anaerobes. Spore forming
Toxin A (enterotoxin) binds brush border of gut
Toxin B (cytotoxin) destroys cytoskeletal structure of enterocytes causing pseudomembranous colitis
Diarrhea after antibiotic use (clindamycin or ampicillin)
Detection of toxin in stool
Metronidazole or oral vancomycin
Anthrax Markers What is special about it? What does it produce? Types
Gram+ spore forming rod
Only bacteria with polypeptide capsule (with D-glutamate)
Antrax toxin
Cutaneous vs Pulmonary
Cutaneous Anthrax
Contact –> black eschar (painless ulcer); can progress to bacteremia and death
Black skin lesion - black eschar (necrosis) surrounded by edematous ring
Caused by Lethal factor and Edema factor (Mimics AC and increases cAMP)
Pulmonary Anthrax
Inhalation of spores –> flu-like symptoms that rapidly progresses to fever, pulmonary hemorrhage, mediastinitis, and shock
Woolsorters’ Disease
Inhalation of Anthrax spores from contaminated wool
Bacillus cereus
Markers
How is it contracted
Types with presentation
Gram+ aerobic rods
Food poisoning. Spores survive cooking rice and keeping it warm results in germination of spores and enterotoxin formation
Emetic type: Rice and pasta. Nausea and vomiting for 1-5 hours caused by cereulide (a preformed toxin)
Diarrheal type causes watery non-bloody diarrhea and GI pain for 8-18 hours
Listeria Monocytogenes Markers Where can it live? How is it acquired? How do they travel?
Gram+ rods
Facultative intracellular microbe
Ingestion of unpasteurized milk/cheese or deli meats. Vaginal transmission during birth
Forms actin rockets to move from cell to cell with characteristic tumbling motility
Listeria Monocytogenes
Diseases caused by them?
Treatment
Amnionitis, Septicemia, and Spontaneous abortion in pregnant women
Granulomatosis infantiseptica, Neonatal meningitis
Meningitis in immunocompromised pts
Mild gastroenteritis in health individuals
Gastroenteritis is self limiting
Ampicillin for infants, immunocompromised and elderly
Actinomyces Markers Air? Acid Fast? Where is it found? Presentation Treatment
Gram+ branching filaments Anaerobic Not Acid Fast Normal oral flora Oral/facial abscesses that drain through sinus tracts forming yellow sulfur granules Penicillin
Nocardia Markers Air? Acid Fast? Where is it found? Presentation Treatment
Gram+ branching filaments
Aerobe
Acid Fast
Soil
Pulmonary infections in immunocompromised
Cutaneous infections after trauma in normals
Sulfonamides
PPD+ vs PPD-
+: Current infection, Past exposure, BCG vaccinated
-: No infection, anergic (steroids, malnutrition, immunocompromised), or Sarcoidosis
Mycobacteria
Stain
Names
Acid Fast Tuberculosis Kansaii (pulmonary TB-like symptoms) Avium-Intracellulare (disseminated nonTB disease in AIDS resistant to multiple drugs. Treat prophylactically with azithromycin) Leprae
Mycobacterium tuberculosis
Symptoms
Weapons
Histo
Fever, Night sweats, Wt loss, Hemoptysis
Cord Factor: inhibits macrophage maturation and induces release of TNFα
Sulfatides (surface glycolipids) inhibit phagosysosomal fusion
Caseating granuloma w/ multinuclear Langhan’s giant cells
Primary TB
Who is at risk?
Course
Non immune host (usually a child)
Hilar nodes + Ghon focus (usually in mid zone of lung) = Ghon Complex
Heals by fibrosis –> immunity and hypersensitivity –> Tuberculin+
Progressive disease
Bacteremia –> miliary TB
Preallergic lymphatic or hematogenous dissemination –> dormancy in several organs –> reactivation in adult life
Secondary TB
Who is at risk?
Initial Course
Reactivation
Partially immune hypersensitized host (adult)
Fibrocaseous cavitary lesion usually in upper lobes
Reactivation in the lungs
CNS (parenchymal tuberculoma or meningitis)
Vertebral body (Pott’s Disease)
Lymphadenitis, Renal, GI
Mycobacterium leparae Temperatures Growth in vitro Reservoir in US Forms Treatment
Likes cool temps: infects skin, superficial nerves (glove and stocking loss of sensation) Cannot be grown in vitro Armadillos Lepromatuous vs Tuberculoid Dapsone + Rifampin
Lepromatous Leprosy Presentation Communicable? Host response? Treatment
Presents diffusely over skin
Communicable
Low cell-mediated immunity with a humoral Th2 response
Dapsone + Rifampin + Clofazimine for 2-5 years
Tuberculoid Leprosy
Presentation
Host response?
Treatment
Limited to a few hypoesthetic hairless skin plaques
High cell-mediated immunity with Th1 cell response
Dapsone + Rifampin for 6 months
Gram- algorithm
Oxidase+, comma shaped: Campylobacter jejuni or Vibrio cholerae
Diplococci –> Maltose test
M+: Neisseria meningitidis. M-: N. gonorrhoeae
Coccoid rods –> Haemophilus influenzae, Pasturella, Brucella, Bordetella pertussis
Rods –> Lactose fermentation test
L+: Klebsiella, E coli, Enterobacter
L-: Oxidase test
O+: Pseudomonas, H pylori
O-: Shigella, Salmonella, Proteus
Lactose-fermenting enteric bacteria
Test
Enzyme
Examples
“test with MacConKEES agar”
Pink colonies on MacConkey’s agar
Purple/black colonies on EMB
E coli grows with purple colonies with green sheen
E coli produces β-galactosidase breaks lactose into glucose and galactose
Citrobacter, Klebsiella, E coli, Enterobacter, Serratia
Gram- and penicillin
Gram- outer membrane layer inhibits entry of penicillinG and vancomycin
May be susceptible to penicillin derivatives (ampicillin, amoxicillin)
Algorithm for Lactose fermenting, Gram- rods
Fast fermenters: Klebsiella, E coli, Enterobacter
Slow fermenters: Citobacter, Serratia
Algorithm for non-Lactose fermenting, Gram- rods
Do Oxidase Test
Oxidase+: Pseudomonas, H pylori
Oxidase-: Shigella, Salmonella, Proteus
Algorithm for oxidase+, Comma shaped Gram-
Grows @ 42: Campylobacter jejuni
Grows in alkaline media: Vibrio Cholerae
Neisseria Markers Fermentation? Product? Kinds?
Gram- diplococci
Both ferment glucose
Produce IgA proteases
Gonococci vs Meningococci
Neisseria Gonococci Capsule Fermentation Vaccine Transmission Residence?
No polysaccharide capsule Only Glucose fermentation No vaccine (due to antigenic variation of pilus proteins) Sexual transmission Polymorphonuclear leukocytes
Neisseria Gonococci
Disease it causes?
Treatment
Gonorrhea, Septic arthritis, Neonatal conjunctivitis, PID, Fitz-Hugh-Curtis syndrome
Ceftriaxone + (azithromycin or doxycycline) for possible chlamydia coinfection
Neisseria Meningococci Capsule Fermentation Vaccine Transmission
Polysaccharide capsule
Ferments Glucose and Maltose
Vaccine (none for type B)
Respiratory and oral secretions
Neisseria Meningococci
Disease it causes?
Prophylaxis
Treatment
Meningococcemia, Meningitis, Waterhouse-Friderichsen syndrome
Rifampin, Ciprofloxacin, Ceftriaxone
Ceftriaxone or PenicillinG
Haemophilus influenzae Markers Transmission Most invasive kind? Non-typeable strains? Weapon Vaccine
Gram- coccoid rods
Aerosol transmission
Most invasive is capsular type B
Cause mucosal infections (otitis media, conjunctivitis, bronchitis)
IgA protease
Vaccine contains B capsular polysaccharide (polyribosylribitol phosphate) conjugated to diphtheria toxoid and other proteins. Give @ 2-18 months
Haemophilus influenzae Growth What diseases does it cause? Prophylaxis Treatment
“When child has the flu, mom goes to V and X store to buy some chocolate”
Chocolate agar requires V (NAD) and X (hematin). Can also grow with S aureus (provides V)
“haEMOPhilus”
Causes Epiglottitis (cherry red in children), Meningitis, Otitis media, Pneumonia
Rifampin
Ceftriaxone
Legionella pneumophila Markers Stains Growth Diagnosis, Labs Transmission Diseases caused by it? Treatment
Gram- rods but stain poorly. Use Silver stain
“French Legionnaire with Silver helmet, sitting around a Charcoal fire with his Iron dagger. He’s no Sissy (cysteine)”
Charcoal yeast extract with iron and cysteine
Ag in urine. Hyponatremia
Aerosol transmission from water source. No person-to-perosn
Legionnaires disease, Pontiac fever
Macrolide or Quinolone
Legionnaires disease
Caused by…
Presentation
Legionella pneumophila
Severe pneumonia, Fever, GI, CNS symptoms
Pontiac fever
Caused by…
Presentation
Legionella pneumophila
Mild flu-like symptoms
Pseudomonas aeruginosa Markers Gross Source Weapons Classic pt that gets it?
Gram- rod. Aerobic (“think AERuginosa - Aerobic”). Non-lactose fermenting, Oxidase+
Produces pyocyanin (blue-green) pigment. Grape-like odor
Water source
Endotoxin (fever, shock), Exotoxin A (inactivates EF2)
Burn victims, CF pt
Pseudomonas aeruginosa
Presentation
Treatment
“PSEUDOmonas”
Wound and burn infections. Hot tub folliculitis. Malignant Otitis externa in diabetics.
Pneumonia (in CF pt), Sepsis (black lesions on skin), External otitis (swimmers ear), UTI, Drug use, and Diabetic Osteomyelitis
Aminoglycoside + extended spectrum penicillin (piperacillin, ticarcillin)
E coli
Weapons
Types
Fimbriae (cystitis and pyelonephritis)
K capsule (pneumonia, neonatal meningitis)
LPS endotoxin (septic shock)
EIEC, ETEC, EPEC, EHEC
EIEC
What does it invade?
What does it cause?
Presentation
“I = Invades Intestines”
Invades intestinal mucosa
Necrosis and inflammation
Presents like Shigella
ETEC
What does it cause?
Toxin
Course
“T = Travelers”
Travelers Diarrhea (watery)
Labile toxin, Stable toxin
No inflammation or invasion
EPEC
Presentation
Toxins
What does it do?
“P = Pediatrics”
Diarrhea in children
No toxin produced
adheres to apical surface, flattens villi, and prevents absorption
EHEC Most common serotype Markers PathoPhys What does it lead to? Toxin Presentation
O157:H7
Does not ferment sorbitol (distinguish it from other E coli)
Swells endothelium –> narrowed lumen –> hemolysis, reduced renal blood flow. Damaged endothelium consumes platelets
Hemolytic Uremic Syndrome: Anemia, Thrombocytopenia, Acute Renal Failure
Shiga-like toxin. Dysentery (toxin alone causes necrosis and inflammation)
Klebsiella Markers Where is it normally? What does it cause? Classic presentation
“4As”
Aspiration pneumonia, Abscess in lungs and liver, Alcoholics, diAbetics
Gram- Rods. Lactose fermenter
Intestinal flora
Lobal pneumonia in alcoholics and diabetics when aspirated. Nosocomial UTIs
Red currant jelly sputum from polysaccharide capsule
Salmonella Markers, Flagella, Dissemination Reservoirs, Produces... Antibiotic, Invasion? Host response? Presentation
Gram- rods. NonLactose fermenting Oxidase-
Flagella+, Disseminated hematogenously
Many animal reservoirs. Produces Hydrogen sulfide
Antibiotics prolong symptoms
Invades intestinal mucosa. Causes Monocytic response
Can cause bloody diarrhea
Shigella Markers, Flagella, Dissemination Reservoirs, Produces... Antibiotic, Invasion? Host response? Presentation
Gram- rods. NonLactose fermenting Oxidase-
Flagella-. Cell-to-cell transmission. no hematogenous spread
Human and primate reservoirs. Does not produces Hydrogen sulfide
Antibiotics shorten excretion of organisms in feces
Invades intestinal mucosa. Causes PMN infiltration
Often cause bloody diarrhea
Salmonella Typhi What does it cause? Found in... Presentation Carrier state?
Typhoid fever
Only in humans
Rose spots on the abdomen, fever, headache, diarrhea
Can remain in gallbladder and causes carrier state
Campylobacter jejuni Markers Presentation Transmission What follows it?
Gram- comma shaped oxidase+ that grows at 42 degs C
Bloody diarrhea in children
Fecal-oral transmission
Guillain Barre Syndrome and Reactive Arthritis
Vibrio Cholerae Markers MoA Presentation Treatment
Gram- comma shaped oxidase+ that grows in alkaline media
Produces toxin that permanently activates Gs –> ↑cAMP
Rice-water diarrhea endemic in developing countries
Oral rehydration
Yersinia enterocolitica
Markers
Transmission
Presentation
Gram- coccobacillus
Pet feces, contaminated milk, pork
Mesenteric adenitis that mimics Crohn’s or Appendicitis
Helicobacter pylori Markers What does it cause? Increases risk for... MoA Treatment
Gram- rods. Doesn’t ferment lactose. Oxidase+, Urease+ (breath test)
Gastritis and duodenal ulcers
Risk factor for Peptic Ulcers, Gastric Adenocarcinoma, Lymphoma
Creates alkaline environment
PPI, Clarithromycin, Amoxicillin, or Metronidazole
Spirochetes
Shape
Names
Visualization
Spiral shaped bacteria with axial filaments
“BLT”
Borrelia (big size), Leptospira, Treponema
Only Borrelia can be visualized using aniline dyes (Wright’s or Giemsa stain) in light microscopy
Treponema can be visualized by dark-field microscopy
Leptospira Interrogans
Where is it found?
Presentation
Who gets it?
Water contaminated with animal urine
Leptospirosis: flu-like symptoms Jaundice, Photophobia w/ conjunctivitis
Surfers and in tropics (Hawaii)
Weil’s Disease
Icterohemorrhagic leptospirosis: Severe jaundice and Azotemia from liver and kidney dysfunction, Fever, Hemorrhage and anemia
Lyme Disease Caused by... Visualization Transmission Reservoir Location Presentation Treatment
Borrelia burgdorferi Aniline dyes (Wright's or Giemsa stain) in light microscopy Tick Ixodes Mouse NE USA "FAKE a key lyme pie" Facial nerve palsy (bilaterally), Arthritis, Cardiac Block, Erythema Migrans Doxycycline, Ceftriaxone
Stages of Lyme Disease
1: Erythema chronicum migrans (bull’s eye) and flu like symptoms
2: Neurologic (facial nerve palsy) and cardiac (AV block) manifestations
3: Musculoskeletal (chronic monoarthritis and migratory polyarthritis), Neurological (encephalopathy and polyneuropathy), and cutaneous manifestations
Syphilis
Caused by…
Visualization
Treatment
Spirochete Treponema pallidum
Dark field microscopy
PenicillinG
Primary Syphilis
Presentation
Diagnosis
Localized disease presenting with painless chancre (with Treponema inside)
Screen with VDRL and confirm with FTA-ABS
Secondary Syphilis
Presentation
Diagnosis
Disseminated disease w/ constitutional symptoms, maculopapular rash (palms and soles), Condylomata lata (with Treponema inside)
Screen with VDRL and confirm with FTA-ABS
Tertiary Syphilis
What does it cause?
Presentation
Diagnosis
Gummas (chronic granulomas), Aortitis (vasa vasorum destruction), Neurosyphilis (tabes dorsalis), Argyll Robertson pupil
Broad-based ataxia, +Romberg, Charcot joint, Stroke w/o HTN
Test spinal fluid with VDRL
Congenital Syphilis
Presentation
When does it happen?
Saber shins, Saddle nose, CNVIII deafness, Hutchinson’s teeth, Mulberry molars
After first trimester
Argyll Robertson Pupil
Pupils constrict with accommodation but is not reactive to light
Associated with tertiary syphilis
“Prostitute’s pupil” accommodates but doesn’t react
VDRL
What is it?
False+
VDRL detects non-specific antibodies that react with beef cardiolipin
“VDRL”
Viruses (mono, hepatitis), Drugs, RF, Lupus, Leprosy
Jarisch-Herxheimer Reaction
Flu like syndrome in Syphilis pt immediately after antibiotics are started due to killed bacteria releasing pyrogens
Cat Scratch
Cat scratch disease from Bartonella Spp
Louse
Recurrent fevers from Borrelia recurrentis
Epidemic Typhus from Rickettsia Prowazekii
Unpasteurized dairy
Brucellosis/Undulant fever from Brucella Spp
Parrots and other birds
Psittacosis from Chlamydophila psittaci
Cattle/sheep amniotic fluid
Q fever from Coxiella burnetii
Lone Star Tick
Ehrlichiosis from Ehrlichia chaffeensis
Ticks, Rabbits, Deer Fly
Tularemia from Francisella tularensis
Animal bite, cats or dogs
Cellulitis, Osteomyelitis from Pastuerella multocida
Dermacentor tick bite
Rocky Mountain Spotted Fever from Rickettsia Rickettsii
Fleas
Endemic typhus from Rickettsia typhi
Plague from Yersinia pestis
Gardnerella vaginalis Markers Presentation Associated w/... Histo Treatment
“I don’t have a CLUE why I smell FISH in the VAGINA”
Pleomorphic gram variable rods
Vaginosis: gray vaginal discharge with fishy smell. Non painful
Associated with sexual activity but not an STD
Clue cell or vaginal epithelial cells covered with bacteria
Metronidazole
Bacterial vaginosis
Overgrowth of certain bacteria in the vagina
Rickettsia rickettsii Gram Where do they live Distribution What does it cause? Presentation
Gram- Obligate intracellular that need CoA and NAD All over USA Rocky Mountain Spotted Fever Rash that starts at wrists and ankles
Rickettsia
Markers
Where do they live?
Gram-. rod-to-coccoid shaped
Obligate intracellular organisms
Rickettsia typhi
What kind of outbreak?
Vector
Presentation
Endemic
Fleas
Headache, fever, rash on trunk
Rickettsia prowazekii
What kind of outbreak?
Vector
Presentation
Epidemic
Human body louse
Rash starts centrally and spreads out sparing soles and palms
Palm and Sole Rash
“CARS driving with your palms and soles”
Coxsackievirus A, Rocky Mountain Spotted Fever, Secondary Syphilis
Ehrlichiosis Caused by... Presentation Vector Histo
Ehrlichia (a kind of rickettsia)
No rash
Ticks
Monocytes with morula (berry-like inclusions) in cytoplasm
Anaplasmosis Caused by... Presentation Vector Histo
Anaplasma (a kind of rickettsia)
No rash
Tick
Granulocytes with morula in cytoplasm
Q fever
Vectors
What causes it?
Presentation
Tick feces and cattle placenta release spores that are inhaled by aerosols as spores. No arthropod vectors
Coxiella burnetii (closely related to rickettsia - obligate intracellular parasite)
Presents as pneumonia
Chlamydiae Markers Cell wall What kind of infections Lab diagnosis? Forms Treatment
Gram- Obligate intracellular parasite
Lacks Muramic Acid and Peptidoglycans
Mucosal infections
Cytoplasmic inclusions seen on Giemsa or Fluorescent Ab-stained smear
Elementary body (small, dense) is infectious and Enters cell via Endocytosis
Reticulate body Replicates in cell by fission. Form seen on tissue culture
Azithromycin (favored) or doxycycline
Chlamydia trachomatis
Causes reactive arthritis, conjunctivitis, non-gonococcal urethritis, and PID
Chlamydia pneumoniae and Chlamydia psittaci
Presentation
Transmission
Reservoir
Atypical pneumonia
Aerosol.
Psittaci notable for avian reservoir
Chlamydia trachomatis
Serotypes
A,B,C: Africa, Blindness (follicular conjunctivitis), Chronic infections
D-K: Urethritis/PID, Ectopic pregnancy, Neonatal pneumonia (staccato cough), neonatal conjuntivitis
Neonatal acquired by passage through birth canal
L1,L2,L3: Lymphogranuloma venereum
Mycoplasma pneumoniae Markers Cell wall Growth Titer
No Gram stain. No cell wall, Membrane contains sterols for stability
Eaton’s agar
Cold agglutinins (IgM) which can agglutinate or lyse RBCs
Mycoplasma pneumoniae
Presentation
XR
Outbreaks
Walking pneumonia: insidious onset, headache, non-productive cough, diffuse interstitial infiltrate
XR looks worse than pt
Outbreaks in military recruits and prisons. Pts under 30
Bordetella pertussis Markers Presentation Growth Treatment
Gram - coccobacillus Whooping cough (staccato cough with deep inspirations) Bordet-Gengou Agar Pre whooping cough: Erythromycin Post whooping cough: Supportive care
