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Micro Bacteria Flashcards

1
Q

Gram+ Cocci lab algorithm

A 
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
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2
Q

Gram+ rods

A 
Clostridium (anaerobe)
Corynebacterium
Listeria
Bacillus (aerobe)
Mycobacterium (acid fast)
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3
Q

Gram+ with branching filaments

A

Anaerobe, not acid fast: Actinomyces

Aerobe, acid fast: Nocardia

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4
Q

Streptococcus algorithm

A

Hemolysis test
Partial hemolysis –> green on blood agar–> α
Complete hemolysis –> clear on blood agar –> β
No hemolysis on blood agar –> γ

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5
Q

α Hemolytic Strep Algorithm

A

“OVRPS”
Capsule, +Quellung, Optochin sensitive –> Strep pneumoniae
No capsule, Optochin resistant –> Viridans streptococci (S mutans)

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6
Q

β Hemolytic Strep Algorithm

A

“B-BRAS”
Group A: Bacitracin sensitive –> S pyogenes
Group B: Bacitracin resistent –> S agalactiae

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7
Q

γ Hemolytic Strep Algorithm

A 
Group D (Enterococcus): Growth in bile and 6.5% NaCl (E faecalis)
Nonenterococcus: Growth in bile, not 6.5% NaCl (S bovis)
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8
Q

β-Hemolytic Bacteria

A 
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)
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9
Q

Staphyloccus aureus
Gram, Shape, Arrangement, Marker
Weapon
Diseases it causes?

A

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)

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10
Q

MRSA
What is it?
Resistent to…

A

Methicillin Resistent Staph Aureus

Resistent to β-lactams because of altered penicillin binding protein

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11
Q

Staphylococcus epidermidis
Where is it normally located
Contaminates what?
What does it infect?

A

Part of normal skin flora
Contaminates blood cultures
Infects prosthetic devices and IV catheters by producing adherent biofilms

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12
Q 
Streptococcus pneumoniae 
Gram, Shape, Arrangement
Weapons 
Markers  
Most common cause of...
Presentation
A

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

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13
Q 
Viridans Group Streptococci 
Markers
Where are they normally
What do they cause?
What does it adhere to?
A

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

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14
Q 
Streptococcus pyogenes 
Markers
Versions w/ diseases
Diagnosis  
Significant protein marker
A

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

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15
Q

Diagnosis of RF

What causes it?

A 
GAS
"JONES"
Joints - polyaarthritis 
Carditis 
Nodules (subcutaneous)
Erythema marginatum 
Sydenham's chorea
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16
Q

Scarlet Fever Presentation

A

Scarlet rash sparing face, Strawberry (scarlet) tongue, Scarlet throat

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17
Q

What GAS presentations can lead to other problems?

A

Pharyngitis –> RF and Glomerulonephritis

Impetigo more commonly precedes glomerulonephritis than pharyngitis

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18
Q 
Streptococcus agalacgtiae 
Markers 
What does it produce?
Colonizes where?
What diseases does it cause? In whom?
Screen
Treatment
A

“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

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19
Q 
Enterococcus 
Names
Markers 
Where are they normally?
Resistant to?
What do they cause?
Bad version?
A

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

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20
Q

Lancefield Grouping based on?

A

Difference in C carbohydrate in cell wall

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21
Q

Streptococcus bovis
Markers
Where does it colonize
What can it cause?

A

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

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22
Q

GDS

A

S bovis, E. faecalis, E. faecium

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23
Q 
Corynebacterium diphtheriae 
Markers 
Plating 
Toxin test?
Stains 
Diseases it causes? How?
Symptoms 
Vaccine
A

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

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24
Q

Spores
What do have in their core?
How do you kill spores?

A

Dipicolinic acid in the core

Autoclave @ 121 degrees C for 15 minutes

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25
Clostridia Markers What do they form? Types
Gram+ rods that are obligate anaerobes. Spore forming | Tetani, Botulinum, Perfringens, Difficile
26
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
27
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)
28
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
29
``` 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
30
``` 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
31
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)
32
Pulmonary Anthrax
Inhalation of spores --> flu-like symptoms that rapidly progresses to fever, pulmonary hemorrhage, mediastinitis, and shock
33
Woolsorters' Disease
Inhalation of Anthrax spores from contaminated wool
34
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
35
``` 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
36
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
37
``` 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 ```
38
``` 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
39
PPD+ vs PPD-
+: Current infection, Past exposure, BCG vaccinated | -: No infection, anergic (steroids, malnutrition, immunocompromised), or Sarcoidosis
40
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 ```
41
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
42
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
43
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
44
``` 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 ```
45
``` 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
46
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
47
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
48
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
49
Gram- and penicillin
Gram- outer membrane layer inhibits entry of penicillinG and vancomycin May be susceptible to penicillin derivatives (ampicillin, amoxicillin)
50
Algorithm for Lactose fermenting, Gram- rods
Fast fermenters: Klebsiella, E coli, Enterobacter | Slow fermenters: Citobacter, Serratia
51
Algorithm for non-Lactose fermenting, Gram- rods
Do Oxidase Test Oxidase+: Pseudomonas, H pylori Oxidase-: Shigella, Salmonella, Proteus
52
Algorithm for oxidase+, Comma shaped Gram-
Grows @ 42: Campylobacter jejuni | Grows in alkaline media: Vibrio Cholerae
53
``` Neisseria Markers Fermentation? Product? Kinds? ```
Gram- diplococci Both ferment glucose Produce IgA proteases Gonococci vs Meningococci
54
``` 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 ```
55
Neisseria Gonococci Disease it causes? Treatment
Gonorrhea, Septic arthritis, Neonatal conjunctivitis, PID, Fitz-Hugh-Curtis syndrome Ceftriaxone + (azithromycin or doxycycline) for possible chlamydia coinfection
56
``` Neisseria Meningococci Capsule Fermentation Vaccine Transmission ```
Polysaccharide capsule Ferments Glucose and Maltose Vaccine (none for type B) Respiratory and oral secretions
57
Neisseria Meningococci Disease it causes? Prophylaxis Treatment
Meningococcemia, Meningitis, Waterhouse-Friderichsen syndrome Rifampin, Ciprofloxacin, Ceftriaxone Ceftriaxone or PenicillinG
58
``` 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
59
``` 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
60
``` 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
61
Legionnaires disease Caused by... Presentation
Legionella pneumophila | Severe pneumonia, Fever, GI, CNS symptoms
62
Pontiac fever Caused by... Presentation
Legionella pneumophila | Mild flu-like symptoms
63
``` 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
64
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)
65
E coli Weapons Types
Fimbriae (cystitis and pyelonephritis) K capsule (pneumonia, neonatal meningitis) LPS endotoxin (septic shock) EIEC, ETEC, EPEC, EHEC
66
EIEC What does it invade? What does it cause? Presentation
"I = Invades Intestines" Invades intestinal mucosa Necrosis and inflammation Presents like Shigella
67
ETEC What does it cause? Toxin Course
"T = Travelers" Travelers Diarrhea (watery) Labile toxin, Stable toxin No inflammation or invasion
68
EPEC Presentation Toxins What does it do?
"P = Pediatrics" Diarrhea in children No toxin produced adheres to apical surface, flattens villi, and prevents absorption
69
``` 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)
70
``` 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
71
``` 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
72
``` 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
73
``` 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
74
``` 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
75
``` 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
76
Yersinia enterocolitica Markers Transmission Presentation
Gram- coccobacillus Pet feces, contaminated milk, pork Mesenteric adenitis that mimics Crohn's or Appendicitis
77
``` 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
78
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
79
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)
80
Weil's Disease
Icterohemorrhagic leptospirosis: Severe jaundice and Azotemia from liver and kidney dysfunction, Fever, Hemorrhage and anemia
81
``` 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 ```
82
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
83
Syphilis Caused by... Visualization Treatment
Spirochete Treponema pallidum Dark field microscopy PenicillinG
84
Primary Syphilis Presentation Diagnosis
Localized disease presenting with painless chancre (with Treponema inside) Screen with VDRL and confirm with FTA-ABS
85
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
86
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
87
Congenital Syphilis Presentation When does it happen?
Saber shins, Saddle nose, CNVIII deafness, Hutchinson's teeth, Mulberry molars After first trimester
88
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
89
VDRL What is it? False+
VDRL detects non-specific antibodies that react with beef cardiolipin "VDRL" Viruses (mono, hepatitis), Drugs, RF, Lupus, Leprosy
90
Jarisch-Herxheimer Reaction
Flu like syndrome in Syphilis pt immediately after antibiotics are started due to killed bacteria releasing pyrogens
91
Cat Scratch
Cat scratch disease from Bartonella Spp
92
Louse
Recurrent fevers from Borrelia recurrentis | Epidemic Typhus from Rickettsia Prowazekii
93
Unpasteurized dairy
Brucellosis/Undulant fever from Brucella Spp
94
Parrots and other birds
Psittacosis from Chlamydophila psittaci
95
Cattle/sheep amniotic fluid
Q fever from Coxiella burnetii
96
Lone Star Tick
Ehrlichiosis from Ehrlichia chaffeensis
97
Ticks, Rabbits, Deer Fly
Tularemia from Francisella tularensis
98
Animal bite, cats or dogs
Cellulitis, Osteomyelitis from Pastuerella multocida
99
Dermacentor tick bite
Rocky Mountain Spotted Fever from Rickettsia Rickettsii
100
Fleas
Endemic typhus from Rickettsia typhi | Plague from Yersinia pestis
101
``` 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
102
Bacterial vaginosis
Overgrowth of certain bacteria in the vagina
103
``` 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 ```
104
Rickettsia Markers Where do they live?
Gram-. rod-to-coccoid shaped | Obligate intracellular organisms
105
Rickettsia typhi What kind of outbreak? Vector Presentation
Endemic Fleas Headache, fever, rash on trunk
106
Rickettsia prowazekii What kind of outbreak? Vector Presentation
Epidemic Human body louse Rash starts centrally and spreads out sparing soles and palms
107
Palm and Sole Rash
"CARS driving with your palms and soles" | Coxsackievirus A, Rocky Mountain Spotted Fever, Secondary Syphilis
108
``` Ehrlichiosis Caused by... Presentation Vector Histo ```
Ehrlichia (a kind of rickettsia) No rash Ticks Monocytes with morula (berry-like inclusions) in cytoplasm
109
``` Anaplasmosis Caused by... Presentation Vector Histo ```
Anaplasma (a kind of rickettsia) No rash Tick Granulocytes with morula in cytoplasm
110
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
111
``` 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
112
Chlamydia trachomatis
Causes reactive arthritis, conjunctivitis, non-gonococcal urethritis, and PID
113
Chlamydia pneumoniae and Chlamydia psittaci Presentation Transmission Reservoir
Atypical pneumonia Aerosol. Psittaci notable for avian reservoir
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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
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``` 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
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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
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``` 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 ```

USMLE (25 decks)

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