Microbiology Flashcards
1
Q
Streptococcus Workup
A
All Strep Catalase Negative
1) Bile Solubility and Optochin sensitivity:
- Bile soluble or Optochin Sensitive - S. pneumo (alpha hemolytic)
If optochin resistant:
2) Bile-esculin test:
- Bile-esculin Positive - Group D Strep
If bile-esculin negative:
3) Hemolysis
- Alpha or gamma hemolytic - Viridans Strep (S. mutans)
If beta hemolytic:
4) Bacitracin sensi
- Group A strep = Bacitracin sensitive (S. pyogenes)
- Group B strep = Bacitracin resistant and CAMP positive (S. agalactiae)
2
Q
Staph Workup
A
All Staph Catalase Positive, Glucose fementers
1) Coagulase
- Coagulase positive - S. aureus
(S. lugdunensis - positive on slide, negative in tube)
If coagulase negative,
2) Novobiocin resistant
- Novobiocin resistant - S. saprophyticus (UTIs)
- Novobiocin sensitive- S. epidermidis (heart valves. IVDU, catheters)
3
Q
Malaria - cycle / severity
P. vivax
P. ovale
P. knowlesi
P. falciparum
P. malariae
A
P. vivax - 48 h, Benign
P. ovale - 48 h, Benign
P. knowlesi - 24 h, Severe
P. falciparum - 48 h, Severe
P. malariae - 72 hour, Moderate
4
Q
Which malaria has 72 hours cycle?
A
P. malariae
5
Q
Which malaria has 24 hour cycle?
A
P, knowlesi
6
Q
Which malaria causes severe disease?
A
P. knowlesi and P. falciparum
7
Q
Which malaria infects all stages of RBC?
A
P. falciparum (rest are retic only)
8
Q
High risk HPV subtypes
A
16, 18, 31, 33
9
Q
Low risk HPV subtypes
A
6, 11, 42, 43, 44
10
Q
Malaria stages
A
Sporozoite - transmitted by mosquito, infects liver
Merozoite - exits liver, enters RBC
Trophozoite - forms in RBC then can become more merozoite or gametocyte
11
Q
Filarial worms - sheath vs nuclei in tail
A
Brugia malayi - sheathed, 2 tail nuclei)
Loa loa - sheathed, + tail nuclei
Wuchereria bancrofti - sheathed, NO tail nuclei
Onchocerca volvulus - unsheathed, NO tail nuclei
12
Q
Chronic active HBV infection serology
A
HBsAg positive
Total anti-HBc positive, IgM negative
HBeAg positive
(Negative anti-HBs, anti-HBe)
13
Q
Chronic inactive HBV infection serology
A
HBsAg positive
Total anti-HBc positive
anti-HBe positive
(Negative anti-HBs, HBeAg)
14
Q
CAMP Test
A
Streak 90 degrees to S aureus culture
Increased clearing at intersetion for:
- Listeria
- Group B strep
15
Q
Non motile enterobacteria
A
Shigella
Klebsiella
16
Q
MacConkey agar
A
Gram negatives
Pink = lactose fermentation
“LEECKS” - Lactose = E coli, Enterobacter, Citrobacter, Klebsiella, Serratia
17
Q
Thayer-Martin agar
A
Neisseria
18
Q
Martin-Lewis agar
A
Neisseria
19
Q
Regan-Lowe agar
A
Bordatella pertussis and parapertussis
20
Q
TCBS agar
A
stool culture, Vibrio
21
Q
S. saprophyticus
Clinical
Catalase
Coagulase
Novobiocin
A
S. saprophyticus
UTIs
Catalase positive
Coagulase negative
Novobiocin resistant
22
Q
S. epidermidis
Clinical
Catalase
Coagulase
Novobiocin
A
S. epidermidis
Heart valves, IVDU, catheters
Catalase positive
Coagulase negative
Novobiocin sensitive
23
Q
A
24
Q
Schistosoma hematobium
Risk factors
Clinical
Egg
A
Schistosome hematobium
Middle East, Africa, snail infested water
Bladder infection, hematuria
Egg with large terminal spine
25
Schistosoma mansoni
Risk factors
Clinical
Egg
Schistosoma mansoni
Caribbean, MIddle East, Africa, snail infested water
GI infection
Eggs with large terminal spine
26
Runyon Group 4
Runyon Group 4 - Fast Growers (< 7d)
M. fortiuitum
M. abscessus
M. chelonae
M. mucogenicum
27
Enterobacteriaceae
Aerobic/anaerobic
Glucose
Nitrate
Catalase
Oxidase
Lactose
Motility
H2S
Enterobacteriaceae
Facultative anaerobes
Glucose fermenter
Nitrate reducer
Catalase positive
Oxidase negative
Lactose fermenters - E coli, Klebsiella, Enerobacter, Citrobacter
Mostly motile - except Klebsiella and Shigella
H2S producers - Salmonella, Citrobacter Proteus
28
Rickettsia
Ehrlichia and Anaplasma
Intracellular in neutrophils or monocytes
Ehrlichiosis, Rocky Mountain Spotted fever
29
Culture negative endocarditis
"HACEK"
Haemophilis
Aggregatibacter
Cardiobacterium
Eikenella
Kingella
30
Runyon Group 1
Runyon Group 1 - Photochromogens
(colored with light)
M. kansasii
M. simiae
M. marinum
M. asiaticum
M. szulgai at 25 C
31
Runyon Group 2
Runyon Group 2 - Scotochromogens
(colored all the time)
M. gordonae
M. flacescens
M. szulgai at 37 C
M. scrofulaceum
M. xenopi (most)
32
Runyon Group 3
Runyon Group 3 - Non-photochromogen
MAI
M. bovis
M. ulcerans
M. haemophilum
M. xenopi (some)
33
CNA agar
inhibits Gram Negatives
34
Bile esculin
Inhibits Gram positives
35
Haemophilus growth requirements
- H. influenzae
- H. parainfluenzae
- H. ducreyi
H. influenzae - factor X (heme) and factor V (NAD)
H. ducreyi - Factor X (sex = X)
H. parainfluenzae - factor V (not sex = not X)
36
Y. pestis growth requirement
25C
37
Vibrio growth requirements
Salts
38
Egg - Football with double knobs
Trichuris trichuris
39
D. latum complication
B12 deficiency
40
Trichuris trichuria complication
Rectal prolapse
41
Fasciola hepatica complication
Bile obstruction
42
Broad based budding
Blastomyces
43
Narrow based budding
Cryotococcus or Histoplasma
44
Germ tubes / pseudohyphae
Candida
45
Large spherules with endospores
Coccioides
46
Candida resistant to fluoconazole
C. krusei
Some C. glabrata
47
Which Candida has no hyphae or pseudohyphae (grow only in yeast form)
C. glabrata
48
Malaria - Banana shaped gametocyte
P. falciparum
49
Malaria - Band forms
P. malariae
50
Malaria - Large intracellular forms
P. ovale
P. vivax
51
Micrococcus
Microscopy
Catalase
Bacitracin
Diff test
Micrococcus:
- Gram positive cocci, clusters of usually 4
- Catalase positive
- Bacitracin sensitive
- Diff from Staph - Modified oxidase test. Also does not ferment glucose (most staph do)
52
Tellurite agar
Selective for Corynebacterium
53
Tinsdale agar
Selects C. diphtheriae from other Corynebacterium
54
B. cereus vs B. anthracis - common vs diff
Common - Catalase+
B. cereus:
- Beta hemolytic
- Motile
B. anthracis
- Gamma hemolytic
- Non motile
55
TSI slant
- Top vs Bottom
- Results
TSI Slant
Top (slant) = lactose/sucrose
Bottom = glucose
- If bottom, facultative anaerobe
- If black, H2S production
56
Swarming pattern of growth
Proteus
57
Brick red pigment
Serratia
58
Vibrio
- Microscopy
- Glucose
Vibrio
- Curved, Gram Negative rod
- Glucose fermenter
59
P. aeruginosa
- Growth pattern
- Growth condition
- Oxidase
P. aeruginosa
- Diffusible blue-green pigment, mucoid colonies in CF patients
- 42C
- Oxidase+
60
Bordatella pertussis - colony morphology
Drop of mercury
61
Francisella - culture requirements
Cysteine
62
Campylobacter - morphology, culture requirements
- Small curved Gram Negative bacilli
- Selective media - Campy CVA. 42C microaerophillic
63
Nocardia vs Actinomyces - common vs diff
Nocardia vs Actinomyces
- Common = anaerobe, Gram positive rods, sulfur granules
- Actinomyces = modified acid fast negative
- Nocardia = modified acid fast positive
64
Molar tooth colonies
Actinomyces
65
C. perfringens - hemolysis
Double zone
Inner beta
outer alpha
66
Mucicarmine stain
Capsule of Cryptococcus
67
Six common dimorphic fungi
Histoplasma capsulatum
Blastomyces
Coccioides
Pracoccioides
Sprotothrix schenckii
Penicllium marneffei / Talaromyces
68
HIstoplasma in tissue
Yeast intracellular in macrophages
69
70
Coccioides
- Geography
- Risks
- Sx
- Dx
- Mold color / appearance
Coccioides
- SW USA, Mexico, S America
- Deserts
- Flu-like sx, some erythema nodosum
- Enzyme immunoassay
- Mold: White and waxy to woolly, "barrell arthrocondia"
71
Coccioides in tissue
Large spherule with endospores
72
Sporothrix schenckii
- Risks
- Sx
- Mold color / appearance
- Yeast color / appearance
Sporothrix
- Rose gardeners disease
- Skin lesion, lymphocutaneous spread
- Mold: beige to black, Daisy wheel or rosette
- Yeast: elongated, Cigar bodies
73
Penicillium / Talaromyces
- Geography
- Sx
- Mold color / appearance
- Yeast color / appearance
Penicillium / Talaromyces
- SE Asia
- Cutaneous or pneumonia in immunocomp
- Mold: green with red diffusible pigment, Skeleton Hands
- Yeast: Transverse fission
74
Cryptococcus neoformans
- Risks
- Sx
- Dx
- Yeast appearance
Cryptococcus neoformans
- Pigeon droppings
- Neuro infection, can infect lungs too
- Dx = antigen test
- Thick capsule (India ink), narrow based budding
75
Malassezia furfur
- Sx
- Culture
Malassezia furfur
- Pityriasis / tinea versicolor
- Lipophillic yeast - requires fatty acid (olive oil)
76
Malassezia furfur in tissue
Spaghetti and meatballs
77
Three dermatophytes
Microsporum
Epidermophyton
Trichophyton
78
Microsporum canis
- Color
- Appearance
While mold with yellow reverse
Thick walled macroconidia, "snap peas"
79
Trichophyton rubrum - culture
White mold with red reverse / diffusion
Pencil shaped macroconidia with tear-shaped microcondia "birds on a wire"
80
Epidermophyton floccosum
- Color
- Appearance
Yellow - khaki green
Large Beaver Tail macroconidia
81
Mold appearances:
Histoplasma
Blastomyces
Coccioides
Paracoccioides
Sporothrix
Talaromyces
Malasseiza furfur
Microsporum
Trichophyton
Epidermphyton
Histoplasma - slender with big roudn buds
Blastomyces - Lollipops
Coccioides - Barrels
Paracoccioides - Mariner's wheel
Sporothrix - Daisy wheel / rosettes
Talaromyces - Skeleton hands
Malasseiza furfur - spaghetti and meatballs
Microsporum - snap peas
Trichophyton - birds on a wire
Epidermphyton - beaver tail
82
Aspergillus family - microscopic appeatance
Large vesicles with conidia branching off (Dandelions)
83
Aspergillus family - mold colors, disease
A. fumigatus
A. flavus
A. niger
A. terreus
- A. fumigatus - blue/green that turns grey, pulmonary
- A. flavus - brownish green-yellow, pulmonary
- A. niger - black with white border, otitis media
- A. terreus - sand colored, immunocomp infection
84
Mucorales
- Appearance
- Sx
Mucorales
- Non-septate hypahe with sac-like sporangium
- Mucormycosis (soft tissue nasal ifection), pulmonary in immunocomp
85
Mucor vs Rhizopus
Rhizopus = has rhizoids
Mucor = no rhizoids
86
Mycobacteria media
Middlebrook
Lowenstein-Jensen
87
Acid Fast Stains
- Ziehl-Neelsen
- Kinyoun
Both carbol fuchsin
ZN - heat
Kinyoun - phenol
88
Mycobacterium TB vs Mycobacterium bovis
M. TB:
- Nitrate / Niacin Positive
- T2H growth
- Pyrazinamide enzyme positive
- Pyrazinamide susceptible
M. bovis:
- Nitrate / Niacin Negative
- T2H no growth
- Pyrazinamide enzyme negative
- Pyrazinamie resistant
89
Mycobacterium that grows at 42C
M. xenopi
90
Mycobacterium leprae - culture, risk, tissue
M. leprae
- No culture
- Risk = armadillo reservoir
- Tissue - AFB in nerve fibers
91
Infection - Transmission,Stage
Giardia
Entamoeba histolytica
Cryptosporidium parvum/hominis
Toxoplasma gondii
- Giardia - fecal-oral, cyst
- Entamoeba histolytica - fecal oral, cyst
- Cryptosporidium - contaminated water, oocyst
- Toxoplasma - oocyst in cat feces or tissue cyst in meat
92
Malaria - only ring forms in RBCs
P. falciparum
93
Trypanosoma brucei
- Vector
- Sx
Trypanosoma brucei
- Tsetse fly (Glossina spp)
- African sleeping sickness - 1) chancre at bite, 2) fever/LAD, 3) CNS disease (sleeping sickness)
94
Trypanosoma cruzi
- Vector
- Sx
Trypanosoma cruzi
- Reduvid or Kissing bug (feces)
- Chagas disease - fever, LAD, HSM, myocarditis, Romana's sign (conjunctival inoculation with vector feces), cardiomyopathy, megaesophagus / megacolon
95
Leishmania
- Vector
- Sx
- Appearance
Leishmania
- Sandfly (promastigote injected)
- Cutaneous = ulcerating lesions; Visceral = mosrtly L. donovani, HSM, cytopenia
- Intracellular organisms
96
Toxoplasma gondii
- Vector
- Sx
Toxoplasma gondii
- Cat feces (oocyst) or undercooked meat (tissue cyst)
- Asx or mononucleosis; if congenital, chorioretinitis, encephalitis, hydrocephalu; ring enhacing lesion in immunocomp
97
Trichomonas vaginlais
- Vector
Trichomonas vaginalis
- Human STD, NO cyst
98
Enterobius vermicularis
- Common name
- Infective form
- Sx
- Egg
Enterobius vermicularis
- Pinworm
- Embryonated ova (ingested or inhaled)
- Perianal pruritus
- Egg flattened on one side
99
Trichuris trichiura
- Common name
- Infective form
- Sx
- Egg
Trichuris trichuria
- Whipworm
- Embyonated ova
- Mostly asx, but can cause abdominal pain, diarrhea, rectal prolapse
- Egg barrel shaped (each end with plug)
100
Ascaris lumbricoides
- Infective form
- Sx
- Egg
Ascaris lumbricoides
- Embryonated ova
- Larvae in lungs can cause eosinophilic pneumonitis, then adults bowel obstruction or migrate many places
- Egg - fertilized is ruffled oval, but unfertilied elongated with knobbly shell
101
Necator americanus / Ancylostoma duodenale
- Common name
- Infective form
- Sx
- Egg
Necator americanus / Ancylostoma duodenale
- Hookworm
- Filiaform Larvae - penetrate skin, migrate to lungm swallowed
- 1) Cutaneous ground itch, 2) Respiratory symptoms, 3) Intestinal symptoms, ***Iron deficiency anemia
- Egg - Colorless shell with embryo inside
102
Strongyloides stercoralis
- Common name
- Infective form
- Sx
- Egg
Strongyloides stercoralis
- Threadworm
- Filiariform larvae - penetrate skin, migrate to lungs, swallwed, then autoinfection
- 1) Cutaneous ground itch, 2) Respiratory symptoms, 3) Intestinal symptoms, *** Eosinophilia
103
Wuchereria bancrofti, Brugia malayi
- Vector
- Infective form
- Sx
Lymphatic filaria (Wuchereria, Brugia)
- Mosquito (Culex, Anopheles, other)
- Larvae
- Lymphatic obstruction - lymphedema, elephantiasis, eosinophilia
104
Onchocerca volvulus
- Vector
- Infective form
- Sx
Onchocerca volvulus
- Black fly
- Larvae
- Cutaneous - pruritus, dermatitis, subQ nodules; River blindness (keratitis, uveitis)
105
Loa loa
- Vector
- Infective form
- Sx
Loa loa (African eye worm)
- Deer fly
- Infective larvae
- Often asx but cornea / calabar swelling
106
Diphyllobothrium latum / Dibothriocephalus latus
- Common name
- Infective form
- Sx
- Egg
- Proglottid
Diphyllobothrium latum / Dibothriocephalus latus
- Fish tapeworm
- Larvae (eat fish that ate infected crustacean)
- Abdominal sx + *** B12 deficiency
- Only tapeworm with operculum on egg
- Proglottid wider than long
107
Taenia saginata / Taenia solium
- Common name
- Infective form
- Sx
- Egg
- Proglottid
Taenia
- T. saginata = beef tapeworm, T. solium = pork apeworm
- Larvae - in undercooked meat
- Mild GI sx, appendicitis or cholangitis; vs. cysticercosis (T. solium) - ingest ova and migrate
- Egg - thickwalled with radial striations
- Proglottid - T. saginata = 7-13 uterin barnches, vs T. solium = 15-30
108
Echinococcus granulosus
- Common name
- Infective form
- Sx
Echinococcus granulosus
- Sheep tapeworm
- Eggs - from dog that got from sheep
- Liver cysts - contain protoscoleces
109
Hymenolepis nana
- Common name
- Infective form
- Sx
- Egg
Hymenolepis nana
- Dwarf tapeworm
- Eggs ingested
- Usually asx, some GI
- Egg w two poles with filaments
110
Clonorchis
- Common name
- Vector / infective form
- Sx
- Egg
Clonorchis
- Oriental Liver fluke
- Larvae - ingested in fish that was infected by snail
- Acute abdominal pain and diarrhea, chronic cholangiis, cholelithiasis, pancreatitis
- Egg - shouldered operculum
111
Fasciola hepatica
- Common name
- Vector / infective form
- Sx
- Egg
Fasciola hepatica
- Sheep liver fluke
- Larvae - on watercress or sheep liver
- Acute abdominal pain, hepatomegaly, diarrhea, eosinophilia. Chonic biliary obstruction
- Egg - oblong with small operculum
112
Fasciolopsis buski
- Common name
- Vector / infective form
- Sx
- Egg
Fasciolopsis buski
- Large intestinal fluke
- Larvae on water plants (from ig feces)
-
- Egg - oblong with small operculum
113
Paragonimus westermani
- Common name
- Vector / infective form
- Sx
- Egg
Paragonimus westermani
- Lung fluke
- Larvae - in undercooked crustaceans
- Acute diarrhea, cough, HSM. Chronic pulmonary sx
- Egg - long with operculum at broad end
114
Schistosoma mansoni
- Vector / infective form
- Sx
- Egg
Schistosoma mansoni
- Larvae - direct contact with infected snail
- Acute swimmer's itch, possible hypersensitivity and fever. Chronic - Colonic polyposis, bloody diarrhea, portal HTN, splenomegaly
- Egg - large lateral spine (Manson had a knife)
115
Schistosoma haemotobium
- Vector / infective form
- Sx
- Egg
Schistosoma haemotobium
- Larvae - direct contact with infected snail
- Acute swimmer's itch, possible hypersensitivity and fever. Chronic - cystitis, urethritis
- Egg terminal spine
116
Schistosoma japonicum
- Vector / infective form
- Sx
- Egg
Schisotosoma japonicum
- Larvae - direct contact with infected snail
- Acute - swimmer's itch, possible hypersensitivity and fever. Chronic - portal HTN, splenomegaly
- Egg with small or absent spine (Japan peaceful)
117
Germ tube positive Candida
C. albicans
C. stellatoidea
C. dubliniensis
118
Hot growing mycobacteria
M. xenopi, M. thermoresistible
119
Cold growing mycobacteria
M. marinum, M. ulcerans
120
M. bovis vs M. TB
M. bovis = niacin neg, nitrate neg
M. TB = niacin pos, mitrate pos
M. bovis = TCH susceptible
M. TB = TCH resistant
M. bovis = pyrazinamide resistant
M. TB = pyrazinamide susceptible
121
Necator americanus vs Strongyloides stercolis
- Common names
- Unique sx
Necator americanus:
- Hook worm
- Iron defic anemia
Strongyloides stercolis:
- Thread worm
- Eosinophilia
122
Malaria - RBCs with irregular edges
P. ovale
123
Acute HBV infection Window period serology
Total anti-Hb Core positive
anti-Hb Core IgM positive
(HBsAG negative)
124
Acute infection non-window period serology
HBsAG positive
Total anti-Hb Core positive
anti-Hb Core IgM positive
(anti-HBs negative)
125
M. kansasii vs M. TB
M. kansasii:
- Photochromogen, slow growing
- Niacin negative, nitrate positive
M. TB:
- Niacin and nitrate positive
126
Bacterial vs Viral vs Fungal Meningitis
- WBC
- Protein
- Glucose
Bacterial:
- WBC > 1000, PMNs
- Very High protein (>200)
- Low glucose (<40)
Viral:
- Less elevated WBC < 300, lymphocytes
- Less elevated protein (<200)
- Normal glucose
Fungal:
- WBC < 500
- Very high protein (>200)
- Normal-ish glucose
