Microbiology Flashcards
Organisms under Prokaryotes
Eubacteria
Cyanobacteria
Archaebacteria
DNA of Prokaryotes
Not enclosed within a membrane and usually a singular circularly arranged
Membrane-bound organelles of Prokaryotes
Absent
Main component of prokaryote CW
Polysaccharide peptidoglycan
Replication of prokaryotes
Binary fission
Only prokaryote/s without CW
Mycoplasma and Ureaplasma
Cytoplasmic membrane of prokaryotes
Fluid phospholipid bilayer WITHOUT CHO and sterol
Only prokaryote/s with CHO and/or sterol in their cytoplasmic mebrane
Mycoplasma and Ureaplasma (sterol)
Site of energy production in prokaryotes
Cytoplasmic membrane
Site of protein synthesis in prokaryote
Free ribosomes
Components of the peptidoglycan layer of prokaryotes
Chains of alternating N-acetyl-d-glucosamine and N-acetyl-d-muramic acid
Other term for the peptidoglycan layer
Murein layer
Structure special to Gram-positive bacteri
Teichoic Acid
Function of teichoic acid
Crystal violet-iodine-teichoic acid-Mg++ complex in insoluble to alcohol
Steps and reagents for Gram staining
1 stain: Crystal violet
Mordant: Gram’s iodine
Decolorizer: Acetone alcohol
2 stain: Safranin
Most critical step in Gram staining
Decolorization
General rule for gram staining: cocci
Gram positive except:
Neisseria
Brahamella
Veillonella
General rule for gram staining: bacilli
Gram negative except: /aerobic/ Bacillus Corynebacterium Erysipelotrix Listeria Mycobacterium Nocardia /anaerobic/ Actinomyces Clostridium Propionobacterium
Spore forming bacteria
Bacillus and Clostridium
Fungi-like bacteria:
Nocardia and Actinomyces
Bacteria seen in Blood film
Borrelia
Hot-staining AFS
Ziehl-Nelseen
Cold-staining AFS
Kinyoun
Steps and reagents for Ziehl-Neelsen Stain
1 stain: Carbol fuchsin
Mordant: Steam/heat
Decolorizer: Acid alcohol
2 stain: Methylene blue or malachite green
Preferred AFS for tissues
Kinyoun
Steps and reagents for Kinyoun Stain
1 stain: Carbol fuchsin
Mordant: Tergitol
2 stain: Acid alcohol
2 stain: Methylene blue or malachite green
Negative for AFS
Blue / Green
Positive for AFS
Red
Specific name for lipid inclusions; specify organism
Much granules; MTB
Specific name for polyphosphate inclusions; specify organism
Babes-Ernst/Metachromatic/Volutin granules; Corynebacterium
Stain for Babes-Ernst granules
Burke’s modified stain
Organism with bipolar bodies
Y. pestis
Stain for bipolar bodies
Wayson’s stain
Stain for spores
Shaeffer & Fulton
Dorner’s
Wirtz & Conklin
Composition of spores
Calcium dipicolinate / Dipicolinic acid
Test to differentiate spore-forming bacteria
/both are Gram-postive/
Bacillus: catalase + (aerobic)
Function of capsule
Increase virulence by preventing phagocytosis
Specific antigen for capsule
K antigen; Vi antigen for S. typhi
Composition of capsule
Continuous polysaccharide except for B. anthracis (polypeptide)
Capsular bacteria
H. influenze
N. meningitidis
S. pneumoniae
B. anthracis
Stains for capsule
Quelllung
Hiss
India Ink / Nigrosin
Bacteria with slime layer instead of capsule and causes prosthetic endocarditis
S. epidermidis
Synonymous to Fimbriae
Pili
Function of pili
Ordinary pili: attachment
Sex pili: conjugation
Atrichous
No flagellum
Monotrichous
Flagellum on one pole
Amphitrichous
Single lagellum at both poles
Lophotrichous
Tuft of flagellum on one or both poles
Peritrichous
Flagella all around the organism
All enterobactericae except Shigella and Klebsiella
Periplasmis flagella
Axial filaments
Found only in Spirochetes
Temperature for motility test
Room temp (25C)
Tests for Motility
Hanging Drop
Semisolid Medium (SIM)
Flagellar stains
Flagellar stains
Contain Tannic acid to precipitate and coat flagella
- Leifson
- Gray
- Fisher and Conn
Tumbling motility
Listeria
Darting motility
Campylobacter
Gliding motility
Capnocytophaga
Component of Mycobacteria that is hard to gram stain
Mycolic Acid
Source of endotoxin
Gram negative bacteria
Differentiate exotoxin and endotoxin : release
Exo: by living cells; metabolically produced
Endo: part of CW; released when CW is lysed
Differentiate exotoxin and endotoxin :heat stability
Exo: labile
Endo: stable
Differentiate exotoxin and endotoxin : immunologic
Exo: converted to toxoids; easily neutralized with anti-toxin
Differentiate exotoxin and endotoxin : Pharmacologic
Exo:
- cytotoxin: kills host cells
- enterotoxin: damage GIT cells
- neurotoxin: interferes with nerve impulses
Endo: non specific; fever, septic shock, DIC
Differentiate exotoxin and endotoxin : Toxicity
Exo: high
Endo: low
Test to detect endotoxin in body fluids and instruments
Limulus Lysaic Test
Reagent: blood of horseshoe cran
Positive result: clumping due to lysate
Fried rice pathogen
Bacillus cereus
Canned good pathogen
Clostridium botulinum
Pathogen in salad/coleslaw
Listeria
Most common pathogen causing food poisoning
Staphylococcus aureus
Obligate aerobes
Brucella, Bordetella, Francisella, Pseudomonas, Neisseria
Obligate anaerobe
Bacteroides, Clostridium
Facultative anaerobe
Staphylococcus, Streptococcus
Microaerophilic
Campylobacter (5% O2 10%CO2 85%N)
Capnophilic
/HACEK/ Haemophilus Actinobacillus Cardiobacterium Einella Kingella
Stain/Test for anaerobes
Methylene blue
Negative: colorless colonies
Candle Jar is used to…
increase CO2 concentration
Temperature ranges for bacteria
Psychrophillic: less than 10C
Mesophillic: 20-40C
Thermophillic: 30-37C
pH ranges for growth of bacteria
Acidophile: pH 3
Alkaline: pH 8-10 (Vibrio)
Clinically relevant: 6.5-7.5
Describe each stage of the growth cycle of bacteria
Lag phase: little to no multiplication; adjustment period
Log phase: max multiplication; active metabolism
Stationary phase: growth = death; exhaustion of nutrients and buildup of toxins
Decline phase: increase in death; increase in toxins; low nutrients; unfavorable pH
Tissue media for Chlamydia culture
McCoy cells
Tissue media for viruses
Chick embryo, Vero cells
Tissue media from African green monkey
Vero cells
Tissue media from lung carcinoma
A549 cells
Tissue media from cervical carcinoma
HeLa cells
- Henrietta Lacks
Tissue media from laryngeal carcinoma
Hep2 cells
Culture media for most non-fastidious bacteria
Simple/General isolation/General purpose media
- nutrient agar/broth
- trypticase soy agar/broth
Culture media with nutrient supplementation
Enriched media
- BAP
- CAP
Culture media for enhance growth of specific bacteria
Enrichment media
- Selenite and tetrathionate broth : Salmonella and Shigella
- Alkaline Peptone Water: Vibrio
Culture media to select the growth of a particular organism and inhibit the growth of others
Selective media
Inhibitors for Gram positive bacteria
Dyes: - Gentian violet - Crystal violet Bile salt: - Sodium desoxycholate
Inhibitors for Gram negative bacteria
Sodium azide
Potassium tellurite
Phenylethyl alcohol
Selective culture medium for MTB
Lowenstein-Jensen; Petragrani
Inhibitor: malachite green
Selective culture medium for C. diptheriae
Mueller tellurite
Inhibitor: potassium tellurite
Selective culture medium for N. gonorrhoeae
CAP with antibiotics
- Thayer Martin = vancomycin + colistin + nystatin
- Modified Thayer Martin = vancomycin + colistin + nystatin + trimethropim
- Martin Lewis = vancomycin + colistin + anisomycin + trimethoprim
- New York City Agar = vancomycin + colistin + amphotericin B + trimetoprim
Selective differential medium for Staphylococcus sp.
Mannitol Salt Agar
- 7.5% NaCl
- Mannitol
- phenol red
MF: yellow colonies = S. aureus
NMF: pink colonies = S. epidermidis, S. saprophyticus
Selective differential media for Vibrio sp.
Thiosulfate Citrate Bile Salt
- Sucrose
- Bromthymol blue (A: yellow; K: green)
SF: yellow
NSF: green
Rapid lactose fermenters of Enterobacteriaceae
/EKE/
E. coli
Klebsiella
Enterobacter
– postive for lactose permease
Late lactose fermenters of Enterobacteriaceae
/SSSCHY/ Serratia Salmonella arizonae Shigella sonici Hafnia Yersinia Citrobacter
– positive for OMPG
Non-lactose fermenters of Enterobacteriaceae
/EEMPPSS/ Edwardseialla Erwinia Morganella Proteus Providencia Salmonella Shigella
Eosin-Methylene Blue Agar
Lactose
LF: Pink to purple
NF: colorless
E. coli: pink colonies with green sheen
Klebsiella: pink mucoid colonies
Enterobacter: pink colonies with dark center (fish eye)
MacConkey Agar
Lactose
Crystal violet, Bile salt
Neutral red (A: red; K: colorless)
LF: pink colonies
NLF: colorless
Hektoen Enteric Agar
Lactose, sucrose, salicin
Bile salt
Bromthymol blue (A: yellow; K: blue)
Ferric ammonium sulfate
/SPACEd/: Green/colorless medium with black
- Salmonella, Proteus, Arizon, Citrobacter, Edwardsiella
Salmonella Shigella Agar
Lactose
Neutral red (A: red; K: colorless)
Ferric citrate
Salmonella: colorless colonies with black
Shigella: colorless colonies without black
Bile Esculin Agar
Group D enterococci
Bordet-Gengou agar
Isolation of B. pertussis (mercury droplet)
Potato-glycerol-based with defibrinated blood and methicillin
Buffered charcoal-yeast extract agar
Enrichment for Legionella spp.
CIN
Selective for Yersinia spp.
Cefsulodin, irgasan, novobiocin
Regain Lowe
Enrichment and selective medium for B. pertussis
Preferred isolation of B. pertussis
Regan Lowe
Skirrow Agar
Campylobacter (42-43C) and Helicobacter (35-37C)
Todd-Hewitt broth with antibiotics
Selective and enrichment for S. agalactiae
Human blood bilayer tween medium
G. vaginalis
Transport media for N. gonorrhea
Transgrow
Medium for susceptibility testing
Mueller-Hilton Agar
Depth: 4mm
pH: 7.2-7.4
24mm disk distance
Media for biochemical testing
TSI, LIA
Triple Sugar Iron Agar
Lactose, Sucrose, Glucose Phenol Red (A: yellow; K: red) Ferrous sulfate (black)
Slant: LF and SF
Butt: GF, gas, H2S
All eterobacteriaceae are gas producers in TSI except
Shigella
Lysine Iron Agar
Glucose, lysine
Slant: Lysine deamination (+ red - purple)
Butt: Lysine decarboxylase (+ purple - yellow)
Lysine carboxylase positive
Salmonella
Lysine deaminase positive
Proteus
Providencia
Morganella
Min. Inhibitory Concentration
Minimum concentration that inhibits bacterial growth
Min. Bactericidal Concentration
Lowest concentration that kills bacteria
Disk diffusion / Susceptibility testing
Kirby bauer
Mueller-Hilton Agar
Causes increased resistance of P. aeruginosa to aminogycosides and decreased activity of tetracyclines to all organisms
Excessive Mg++ and Ca++
E-test
Susceptibility testing using plastic test strips with antimicrobial concentration gradient
Automated susceptibility testing
Measures optical density using Vitek systems and validated by Advanced Expert System (AES) software
Antimicrobial agents that interfere with CW synthesis
Beta-lactams (penicillin)
Bacitracin
Cycloserine
Glycopeptides
Antimicrobial agents that interfere with Protein synthesis
Aminoglycosides (-mycin, -micin)
Tetracycline (inhibit bone growth)
Chloramphenicol (last resort! causes aplastic anemia)
Antimicrobial agents that interfere with Nucleic Acid synthesis
Sulfonamides (inhibit folic acid)
Rifampicin (causes orange-red secretions)
Antimicrobial agents that interfere with cell membrane function
Polymyxin
Antimicrobial agents that interfere with fungi
Amphotericine B, nystatin, anisomycin
Sterilization vs Disinfection vs Antiseptic
Sterilization: kills ALL forms of microbial life
Disinfection: destroy all pathologic organisms but not necessarily all organisms
Antiseptic: Microbiostatic agents used on living tissues
Most effective method of sterilization
Autoclave
Specifics for autoclave (media and instruments)
121C at 15lbs psi for 15mins
Specifics for autoclave (medical waste)
132C for 30-60mins
Quality control for autoclave
Spores of Bacillus stearothermophilus
Types of fractional sterilization
a. Tyndallization
b. Inspissation
Flowing steam 100C for 30mins for 3 days
Tyndallization
75-80C for 3 hours for 3 days
Inspissation
Alternate heating, incubation, heating
Fractional sterilization
For sterilization of inoculating loops and needles
Flame
Oven for sterilization - temp and time
160-180C for 90-120min
Quality control for oven
Spores of Bacillus subtilis
Most common method for treating infectious waste;
870-980C
Incinaration
98% effective filter
Asbestos filter
100% bacterial sterility
0.22 micrometer
Membrane filter
Filtration of air
High-efficiency particulate filters
0.2 micrometer
Sterilizing plastic syringes, catheters, or gloves
Ionizing radion
Gamma rays = short wavelength, high energy
Most common chemical sterilant
Cold sterilization
For materials that cannot be autoclaved
Ethylene oxide
Sterilize HEPA filters in BSCs
Formaldehyde vapor and vapor phase hydrogen perocide
Sporicidal
Does not corrode lenses, metal, or rubber
Cold sterilization
Glutaraldehyde
Effective in the presence of organic material
Cold sterilization
Peracetic acid
Boiling as disinfectant
100C for 15mins
Disinfectant to eliminate food-borne pathogens
Pasteurization
Pasteurization at 63C for 30 mins
Batch Method
Pasteurization at 72C for 15 mins
Flash Method
Long wavelength, low energy
Non-ionizing radiation
e.g. mercury lamps
Phenol, phenolics, QUATs, chlorine, 2% aqueous glutaraldehyde
Disinfectant
Alcohol, tincture iodine, iodophor
Antiseptic
Why is 70% ethyl alcohol more effective than 95%?
Water hydrolizing bonds in protein molecules make the killing more effective
Can be used as a disinfectant to kill endospores but toxic to humans
Aldehydes: formaldehyde, glutaraldehyde
Iodine or chlorine disinfectant
Halogens
Composition of iodophor
Iodine + detergent
Neutralize chlorine with…
sodium thosulfate
Examples of heavy metals as disinfectants
Hg: merthiolate; antiseptic, antifungal
Cu: Algicide
Ag(NO3): Credes prophylaxis
Expression of the bactericidal power of a particular substance as compared to pure phenol
Phenol coefficient = highest dilution of sample needed / highest dilution of phenol needed
Quality control for ionizing radiation
Bacillus pumilis
Quality control for ethylene oxide
Bacillus sibtilis var. globii
BSC: open front, negative pressure, sterilize air going out
BSC Class 1
BSC: sterilize air going in and out; also known as LAMINAR FLOW BSC
BSC Class 2
BSC: system is entirely clode; air entering and leaving is sterilized by HEPA filter
BSC Class 3
Airflow patter of BSC Class 1
Enter front –> rear –> top –> through HEPA filter
Airflow patter of BSC Class 2-A
70% recirculated through HEPA
vExhaust via HEPA
Airflow patter of BSC Class 2-B1
30% recirculated through HEPA
Exhaust via HEPA and hard-ducted
Airflow patter of BSC Class 2-B2
No recirculation
Total exhaust via HEPA and hard-ducted
Airflow patter of BSC Class 2-B3
Same with Class 2-B2 but under negative pressure
Exhaust air is ducted
Airflow patter of BSC Class 3
Supply air inlets through 2 HEPA filters
Examples of critical values in microbiology
- positive blood culture
- postive CNS gram stain or culture
- postive cryptococcal antigen test or culture
- postive blood smear for malaria
- S. pyogenes from a sterile site
- MTB culture positive
- S. agalactiae or herpes simplex virus from genital site of pregnant woman
Signs of growth in blood culture
Turbidity
Clot
Hemolysis
Bubbles
Additive in blood culture media set
SPS 0.025% (yellow top)
- prevents phagocytosis
- neutralizes bactericidal effect of blood serum (complement)
When patient is on antimicrobials
use thiol broth or antimicrobial removal device
Culture for throat and nasopharyngeal specimen
Todd-Hewitt broth - fluorescence mincroscopy of Beta Strep
Most abundant normal flora of throat
Alpha-hemolytic strep: Viridans
Most common pathogen in throat
Group-A strep: S. pyogenes
Culture for H. influenza nasopharyngeal swab
BAP or CAP with S. aureus streak
Culture for N. meningitidis nasopharyngeal swab
enriched BAP
Culture for B. pertussis nasopharyngeal
Charcoal cephalexin medium (Regan Lowe)
Bartelette’s critieria
For sputum specimen
< 10 epithelial cells / LPF = high saliva content
> 25 /LPF = pathologic
Additive for urine
Boric acid
Collection for urine
a. Midstream clean-catch
b. Catheterized urine
c. Suprapubic urine – anaerobic culture
Most common agent of UTI
E. coli > 100000 CFU / mL
Factors for callibrated loop for urine specimens
1 microliter loop x 1000
10 microliter loop x 100
Culture for genital specimens
McCoy’s media
How many tubes/collections for CSF?
1: chem and sero
2: micro : most important
3: hema and physical
Causative agent for meningitis for neonatal
Group B step and Gram negative rods
- S. agalactiae
Causative agent for meningitis for under 5
H. influenza
Causative agent for meningitis for for 5-29
N. meningitidis
Causative agent for meningitis for 30 up
S. pneumoniae
Temp storage for CSF
37C
Temp storage for urine, stool, swab, sputum
4C
Serum
-20C for 1 week
Tissues or specimens for long-term storage
-70C
Staphylococcus vs Micrococcus : morphology
Staph: in clusters
Micro: in tetrads/sarcinae
Describe Alpha hemolysis
- Incomplete / partial lysis of RBCs around the colony
- Greenish discoloration around colony
Describe Beta hemolysis
- Complete lysis of RBCs around the colony
- Clear area around the colony
Describe Gamma hemolysis
- No lysis of RBCs
Describe Alpha-Prime hemolysis
- Small zone of alpha hemolysis surrounded by a zone of beta hemolysis
- Occurs after refrigeration
Differentiate growth of Staph spp. in Loeffler’s Serum Slant
S. aureus: golden yellow
S. citreus: lemon yellow
S. epidermidis: white
Only Mannitol-Fermenter Staphylococcus species
S. aureus
Medium for mannose fermentation
Mannitol Salt Agar (MSA)
Positive result for Catalase test
Effervescence / Bubbles
Staph vs Strep: Catalase test
Staph: +
Strep: -
Staphylococcus vs Micrococcus : Lysotaphin
Staph: S
Micro: R
Staphylococcus vs Micrococcus : Bacitracin
Staph: R
Micro: S
Staphylococcus vs Micrococcus : Modified oxidase
Staph: -
Micro: +
Staphylococcus vs Micrococcus : Glucose utilization
Staph: fermenter
Micro: Oxidizer
Positive result for Modified Oxidase test
Blue
CHO Oxidation Fermentation Test : indicator
Bromthymol blue
- positive: yellow
Most important pathogenic determinant of S. aureus
Coagulase
Slide coagulase: detects, reagent, positive result
- Detects coagulase factor
- EDTA > Citrate
- Clumping
Tube coagulase: detects, reagent, positive result
- Detects free coagulase
- Rabbit’s plasma
- gel-like fibrin clot
DNAse test : medium
DNA with methyl green
- positive result is clearing of medium
- : S. aureus, Moraxella, Serratia
S. epidermidis vs S. saprophyticus: Novobiocin
S. epidermidis: S (16mm)
S. saprophyticus: R
Pathologic determinants of S. aureus
- inhibits phagocytosis
Protein A
Pathologic determinants of S. aureus
- converts fibrinogen to fibrin; may coat neutrophils with fibrin to prevent phagocytosis
Coagulase
Pathologic determinants of S. aureus
- associated with initiation of skin infections
Lipase
Pathologic determinants of S. aureus
- aka spreading factor
Hyaluronidase
Pathologic determinants of S. aureus
- degrades DNA
DNAse
Pathologic determinants of S. aureus
- associated with staphylococcal scalded skin syndrone
Exfoliatins
Pathologic determinants of S. aureus
- lysis of neutrophils and macrophages
Leukocidins
Pathologic determinants of S. aureus
- lyse erythrocytes
Hemolysins
Pathologic determinants of S. aureus
- associated with food poisoning and TSS
Enterotoxins
Drug of choice for serious staphylococcal infections
Vancomycin
Gold standard for MRSA detection
mecA gene
- by molecular NA probes
- PRC amplification
Lancefield Group A : species
S. pyogenes
Lancefield Group B : species
S. agalactiae
Lancefield Group C : patho
Pneumobia, cellulitis, abscess
Lancefield Group D: species
S. bovis
S. equinus
Lancefield Group A : patho
URTI
Scarlet fever
Erysipelas
Impetigo
Lancefield Group B: patho
Neonatal infections
Lancefield Group D : patho
UTI
Would infections
Lancefield Group D subgroup resistant to penicillin
Enterococci
Brown’s classification of Streptococcus spp is based on what?
Hemolysis pattern
Strep spp. with alpha hemolysis
- S. pneumoniae
- Viridans
- Some Group D
Strep spp with beta hemolysis
- Group A, B, C, some D
Strep spp with gamma
Most Group D
Hemolysins produced by Streptococcus spp.
Streptolysin S
- non-antigenic
- surface hemolysis
Streptolysin O
- antigenic
- sub-surface hemolysis
Organism with lancet flame, bullet-shaped diplococci morphology
S. pneumoniae
Growth of Streptococcus spp. on BAP
Pinpoint colonies with hemolytic patterns
Streptococcus spp on Bile-esculin agar
Positive for Group D
- positive result: brown-black precipitate
Group D subgroup with growth in 6.5% NaCl
Non-Enterococci
Group D subgroup with PYRase
Enterococci (and Group A)
CAMP test on Streptococcus spp.
Positive: Group B
Hippurate hydrolysis on Streptococcus spp.
Postive: Group B
All streptococcus species are resistant to bacitracin except
Group A (S. pyogenes)
All streptococcus species are resistant to trimetoprima except
Group C
Susceptibility test for Scarlet Fever (S. pyogenes)
Dick’s test
Diagnostic test for Scarlet Fever (S. pyogenes)
Schultz-Charlton
Not categorized under Lancefield
Alpha hemolytic on BAP
S. pneumoniae
Viridams strep
S. pneumoniae vs Viridans : Bile solubility
S. pneumo: +
Viridans: -
S. pneumoniae vs Viridans : optochin susceptibility
S. pneumo: S
Viridans: R
S. pneumoniae vs Viridans : Neufeld Quellung
S. pneumo: +
Viridans: -
Streptococci needing cystein or vit. B6
Abiotrophila spp.
Streptococci thiol-requiring
S. adjacens
S. defectivus
Gram-negative diplococci
Neisseria
Neisseria establish disease by
Attachement in the mucous membranes of the host through pili
Presumptive test for N. gonorrhoeae
Superoxol test
+ : violent bubbling
Definitive ID of N. gonorrhoeae
Culture on enriched chocolate agar
Disease and illnesses associated with N. gonorrheae
- Leading cause of STD
- Ophthalmia neonatorium
Disease and illnesses associated with N. meningiidis
- Leading cause of meningitis in adolescents
- Waterhouse-Friderichsen syndrome
Cultivation of Neisseria (except N. gonorrheae)
- 5% sheep blood and chocolate agar plates
- 37C
Enterobacteriaceae : motility
Peritrichous except Klebsiella and Shigella (NM)
Enterobacteriaceae : Glucose fermentation
GF
Enterobacteriaceae : Catalase test
Positive
Enterobacteriaceae : Oxidase test
Negative
Antigenic structures of Enterobacteriaceae
- K antigen
- heat-labile
- capsular Ag - O antigen
- heat-stable
- somatic Ag - H antigen
- flagellar Ag
- denatured by heat or alcohol
- counterpart (anti-H Ab) : IgG
Sugar components of TSI
10 parts glucose
10 parts sucrose
1 part glucose
Indole detects
Cryptophanase
Positive result for indole
Red ring
Medium for indole
Tryptone broth or Sulfur-Indole medium
Medium for MRVP
Peptone Glucose broth
Indole test indicator/s
Ehrlich’s
Kovac’s
PDAB
MRVP test is for?
MR: methyl red –> glucose fermentation –> red (+)
VP: Voges Proskauer –> detects acetoin –> (+)
Most enterobacteriaceae will give _____ results for MR and VP reactions
Opposite
Salmonella vs Shigella :Malonate utilization test
Positive: blue –> Salmonella
Negative: green / yellow –> Shigella
Rapid urease producers (within 2-4 hours)
Providencia
Proteus
Morganella
Slow urease producers (after 4 hours)
Citrobacter Klebsiella Enterobacter Yersinia Serratia
Phenylanalun deaminase positive
Providencia
Proteus
Morganella
Gelatin liquefaction positive
Serratia
Proteus
Produce cholera-like toxin
Enterotoxigenic E. coli (ETEC)
Cause Shigella-like infections
Enteroinvasive E. coli (EIEC)
Non-invasive, produces no toxin E. coli strain
Enteropathogenic E. coli (EPEC)
Responsible for outbreaks of diarrhea especially in newborns and infants
Enteropathogenic E. coli (EPEC)
Produce verotoxin
Enterohemorrhagic E. coli (EHEC)
Verotoxin is a cytotoxin resembling that of _________
S. dysenteriae
Most severe manifestation of EHEC
Hemolytic uramic syndrome = elevated retics
EHEC is frequently associated with what serotype
E. coli O157:H7
EHEC on MacConkey with sorbitol
Colorless colonies –> only strain that is sorbital negative
E. coli strain that causes watery diarrhea and produces hemolysin-like toxins
Enteroaggregative E. coli (EAEC)
Friedlander’s bacilus
Klebsiella pneumoniae
Grame negative bacilli exhibiting mucoid growth, large polysaccharide capsule
Klebsiella
Purulent sinus infections
Klebsiella ozaenae
Granuloma of nose and oropharynx
Klebsiella rhinoscleromatis
Gram negative bacilli that cause opportunistic infections like UTI, RT, and wound infections
Enterobacter
Most predominent isolate of Enterobacter
E. cloacae
Enterobacter that produces yellow pigmentation that intensifies at 25C
E. sakazaki
Gelatinase +
Common opportunistic pathogen in hospitalized patients
Serratia
Serratia species that produce red pigmentation
S. rubidea
S. marcescence
Serratia species that produce rancid potato-like odor
S. odorifera
Most common causes of Typhoid fever
S. typhi
S. paratyphi
S. cholerasuis
Widal’s test: high titer of O >= 1:160
Active infection
Widal’s test: high titer of H >= 1:160
Past infection or immunity
Widal’s test: high titer of antibody to Vi antigen
Carriers
Natural habitat is limited to intestinal tracts of humans and other primates, where they produce bacillary dysentery
Shigella
Resembles Salmonella but are ONPG + and LDC -
Citrobacter
Source of antigen for Well-Felix reaction
P. vulgaris
- OX-28
- OX-19
P. mirabilis
- OX-K
Normal intestinal flora that may cause UTI and other infections that are often resistant to antimicrobial therapy
Providencia
Can be isolated from the environment
Edwardsiella
Yersinia motility
Motile at room temp
Non-motile at 37C
Common vector of Yersinia
Xenopsylla cheopsis (rat flea)
Stalictite pattern in broth cultures
Yersinia pestis
IMVC reaction of E. coli
++–
IMVC reaction of Klebsiella
–++
Most common cause of death of contaminated units
Y. enterocolitica
Culture for Y. enterocolitica
CIN medium –> bull’s eye colonies
Most common contaminant of donor units
Bacillus
IMVC reaction of Enterobacter
–++
Fruity/grape-like odor
Pseudomonas aeruginosa
Grape-like or corn tortilla-like odor of P. aeruginosa isa a results of the production of
2-aminoacetophenone
Old sock odor
S. aureus
Putrid odor
P. mirabilis
Mousy or musty basement smell
Haemophilus spp.
Freshly mowed field odor
Nocardia spp.
Produces blue-green pigment
P. aeruginosa
Blue-green pigments of P. aeruginosa
Pyocyanin
Pyoverdin
Swimmer’s ears
Pseudomonas aeruginosa
Simmer’s itch
Blood flukes
Swimming pool granuloma
Mycobacterium marinum
Skin lesion produced by P. aeruginosa
Ecthyma gangrenosum
Glander’s disease
Burkholderia mallei
Whitemore’s bacillus
Burkholderia pseudomallei
Causes melioidosis (Vietnamese timebomb disease)
Burkholderia pseudomallei
Preferred incubation for Haemophilus
35-37C
Capnophilic
with X and V factors
Species that require both X and V factors
Haemophilus influenzae
H. hemolyticus
H. aegypticus
Haemophilus species that does not requirer neither of the X nor Y factor
H. aphrophilus
Preferred incubation for Haemophilus
35-37C
Capnophilic
with X and V factors
Species that require both X and V factors
Haemophilus influenzae
H. hemolyticus
H. aegypticus
Haemophilus species that does not requirer neither of the X nor Y factor
H. aphrophilus
Formerly known as Pfeiffer’s bacillus
H. influenzae
Most frequently encountered serotype of H. influenzae in infections
B serotype
Dew drops or satellite colonies around S. aureus
Haemophilus influenzae
Koch-Week’s bacillus
Haemophilus aegypticus
Causes pink eye conjuctivitis
Haemophilus aegypticus
Smallest pathologic bacilli
Haemophilus ducreyi
Infective agent of soft chancre / chancroid
Haemophilus ducreyi
Direct examination shows small bacilli in a school of fish arrangement
Haemophilus ducreyi
Infective agent of hard chancre
Treponema pallidum
Components of Regan Lowe media
Charcoal, horse blood, amphotericin B, cefalexin
Three stages of Whooping cough
- Catarrhal : flu-like symptoms
- Paroxysmal: repetitive coughing episodes
- Convalescent: recovery
S-shaped, microaerophilic organism associated with peptic and duodenal ulcers
Helicobacter pylori
Agent of undulant fever and Malta fever
Brucella
Medium for Brucella
Blood or bone marrow specimens in Castaneda bottlesfor 3-4 weeks
Causative agent of whooping cough
Bordetella pertussis
Ideal specimen for whooping cough dx
Nasopharyngeal swab
Colonies of Bordetella in Regan-Lowe medium
Mercury droplets
Brucella abortus host
Cattle
Brucella melitensis
Sheep/goat
Test/stain to identify Brucella species
Thionine and basic fuschin
Brucella species that is inhibited by thionine but resistant to basic fuschin
B. abortus
Brucella species that is resistant to both thionine and basic fuschin
B. melitensis
Causative agent for Legionnaire’s disease
Legionella pneumophila
Causative agent for Pontiac fever
Legionella pneumphila
Causative agent for Pittsburgh pneumonia
Legionella micdadei
Wiga’s agent of pneumonia
Legionella bozemanni
Found in both natural and artificial water sources, in water-cooling towers for air-conditioning and heating systems
Legionella
Culture medium for Legionella
Beye medium
Stain for Legionella
Dieterie’s stain
Specimen for dx of Legionella
Bronchial wash, expectorated sputum
Agent of pasteurellosis
Pasteurella multocida
Definitive host of Pasteurella
Oral cavity and respiratory and gastointestinal tracts of cats and dogs
Causative agent for bacterial vaginosis characterized by foul smelling, grayish vaginal discharge
Gardnerella vaginalis
Causative agent of rat bite fever and haven hill fever
Streptobacillus moniliformis
Produce bleach-like odor
Eikenella corrodens
Corroding bacterium; part of the gingival and bowel flora
Eikenella corrodens
With the ability to produce violacein, a purple pigment
Chromobacterium violaceum
Only non-motile Bacillus
B. anthracis
Smallest vacteria
Myoplasma
Causative agent of black escar
Bacillus anthracis - cutaneous anthrax
Pulmonary anthrax
Woolsorter’s disease
Colony of B. anthracis on BAP
Medusa head
Colony of B. anthracis on MHA with penicillin
String of pearls
Actinomyces colonies on BAP
Molar tooth
MTP colonies on BAP
Cauliflower
Mycoplasma colonies on BAP
Fried egg
Specimen for food poisoning associated with B. cereus
Food
B. anthracis vs B. cereus : motility
BA: NM
BC: M
B. anthracis vs B. cereus : hemolysis on BAP
BA: gamma
BC: beta
Pathology of Clostridium perfringes
Myonecrosis (gas gangrene) and food poisoning
ID test for Clostridium perfringes
Lecithinase (Nagler reaction)
- inner complete theta toxin
- outer alpha-toxin and lecithinase
Pathology of Clostridium botulinum
Food (canned goods) and wound botulinism
Floppy baby
Infant botulism (caused by C. botulinum)
Spores of C. botulinum
Oval and subterminal
ID test for Clostridium botulinum
Lipase test (+)
Etiologic agent of tetanus
Clotridium tetani
Other term for C. tetani
Devil’s green / Risus sardonicus
Neutrotoxin produced by C. tetani
Tetanospasmin
Effect of tatenospasmin
Spastic contraction
Spored of C. tetani
Round and terminal
Causative agent of lampy jaw
Actinomyces
Impostant cause of antibiotic (usually Clindamycin) associated pneudomembranous colitis
Clostridium difficile
Spores of C. difficile
Oval and subterminal
AKA Klebs-Loeffler bacillus
Corynebacterium diphtheriae
Pathology of Corynebacterium diphtheriae
Pseudomembranous formation of the oropharynx due to exotoxin
Corynebacterium diphtheriae on LSS and Pai’s coagulated egg
Narrow zone of beta hemolysis
Inclusions found in Corynebacterium diphtheriae
Babe’s-Ernst/Metachromatic granules
Corynebacterium diphtheriae on Modified Tinsdale’s agar
Black with brown halo
Corynebacterium diphtheriae on CTBA
Black colonies
Gravis type
1-2mm colonies on blood agar, largest colonial type
Mitis type
Fried egg appearance with bleach like odor
Intermedium type
Small, black colonies on colonies with gray borders on tellurite medium
In vivo Toxigenecity Test for Corynebacterium
Animal inoculation (guinea pig)
In vintro Toxigenecity Test for Corynebacterium
Elek’s Immunodiffusion Technique
Susceptibility test for Diphtheria
Schick’s Test
Resistant to a number of antibiotics and is associated with endocarditis, pneumonia, and peritonitis
Corynebacterium jeikenum
Non-spore forming Clostridium
C. perfringens
Only non-motile pathologic Clostridium species
C. perfringens
Lecithinase positive Clostridium species
C. perfringens
Lipase positive Clostridium species
C. botulinum
Lactose fermenter Clostridium species
C. perfringens
Non-glucose fermenter Clostridium species
C. tetani
How to differentiate CAMP + S. agalactiae and L monocytogenes
Listeria monocytogenes: Catalase + (Aerobic)
Streptococcus agalactiae: Catalase - (Non-aerobic)
Culture for L. monocytogenes
McBribe
Virulence test for L. monocytogenes
Anton’s Test or Ocular Test (rabbit)
To distinguish Listeria from Corynebacterium
Listeria: motile and salicin fermenter
Corynebacterium: NM and NSF
Causative agent for Erysipelloid
Erysipelothrix rhusiopathiae
Causative agent for Erysipelas
Streptococcus pyogenes
Causative agent for Butcher’s disease
Erysipelothrix rhusiopathiae
Normal flora of the mouth, GIT, and vaginal canal that maintains the vaginal pH
Lactobacillus acidophilus
Culture for Lactobacillus acidophilus
Tomato juice agar
Koch’s bacillus
Mycobacterium tuberculosis
Content of CW of MTB
High lipid due o mycolic acid and cord factor
Resistanece of MTB
Resistant to drying and chemical disinfections
Easily killed by moist heat; boiling, pasteurization, or steam (autoclave) for 10mins
Ghon complexes
Calcified tubercles
Skin test for TB
PPD – Purified Protein Derivative
- heat-killed ammonium sulfate
- precipitated organism injected intradermally
- redness after 48 hours
What Type of Hypersensitivity is PPD
Delayed hypersensitivity
Primary drugs for MTB
Streptomycin, isoniazid, rifampicin, ethambutol, pyrazinamide
Applicable specimens for MTB
Sputum Bronchoscopy aspirate Blood CSF Pellicle / weblike clot
Method for decontamination and digestion of Mycobacteria
N-acetyl-L-cysteine (NALC) – digesting
NaOH – decontaminant
Requirements for MTB culture
- Nutrient req of protein / egg
- Malachite green as inhibitor
Stain used for MTB culture for color-blind microscopists
Spengler’s
MTB on different stains: Ziehl-Neelsen Kinyoun Fite-Faraco's Auramine-rhodamine Stain (Truant's) Pappenheim Baumgarten's
- Ziehl-Neelsen: red
- Kinyoun: red
- Fite-Faraco’s: red
- Auramine-rhodamine Stain (Truant’s): fluorescent organisms on black bg
- Pappenheim: red
- Baumgarten’s: blue
CDC method for MTB reporting
0 - 1-2/300 fields +/- REPEAT ON SECOND SLIDE 1-9/100 fields 1+ 1-9/10 fields 2+ 1-9/field 3+ >9 / field 4+
Causative agent for Hansen’s disease or leprosy
Mycobacterium leprae
Animal used for experiments on Hansen’s disease due to it’s suscetibility
Armadillo
Susceptibility test for leprosy
Lepromin test
Treatment for leprosy
Sulfon depson
Causative agent for TB in animals/cattle
Mycobacterium bovis
Causative agent for TB in birds
Mycobacterium avium
Battery bacillus
Mycobacterium avium-intracellulare complex
Culture for M. leprae
Footpads of mice; palisade or parallel
Yellow bacillus
M. kansasii
Tapwater bacillus
M. gordonae
Radish bacillus
M. terrae
Culture for M. fortuitum-chelonae
MAC without Crystal violet
MTB on Niacin test
MTB lacks the enzyme to convert niacin to niacin nucleotide;
MTB: yellow
MTB on Nitrate reduction
a. Broth: pinkish red
b. Strip: blue
Mycobacterium on heat-stable catalase
Negative
Mycobacterium on Tween 80 hydrolysis
ID for M. kansaii + pink
Mycobacterium on Arylsulfate test
ID for M. fortuitum-chenolae
Causative agent for Whipple’s disease
Tropheryma whipplei
Helical aerobe organism that causes rat bite fever and is referred to as Sodoku
Spirillum minus
Stain for Spirochetes
- Levaditi’s
- Warton-Starry
- Fontana Tribondeu
Spirochete metolity
Cork-screw motility due to periplasmic flagella
Causative agent louse-borne relapsing fever
Borrelia recurrentis
Vector for Louse-borne relapsing fever
Human louse
Vector for Tick-borne relapsing fever
Ornithodoro’s tick
Causative agent Tick-borne relapsing fever
Borrelia hermsii
Causative agent for Lyme Disease
Borrelia burgdorferi
Vector for Lyme disease
Ixodes/Deer tick
Stages of lyme disease
Stage 1: lesion - erythema chronicum migrans
Stage 2: dissemination through blood to nomes, CNS, heart, liver, etc
Stage 3: Neurological abnormalities, arthritis, skin lesions
Tightly twisted spirochete
Treponema
Venereal syphilis
Treponema pallidum subsp. pallidum
Stages of Syphilis
Primary: Hard chancre
Secondary: condylomata lata
Latent: Asymptomatic
Tertiary: Gummas, neurosyphilis
Testing for each stage of syphilis
Primary: dark field microscope
Secondary: Dark field or serology
Tertiary: Serology
Tertiary: Serology
Tabes dorsalis
Degradation of lower spinal cord
Yaws
Chronic nonvenereal disease of the skin and bones
Causative agent of Yaws
T. pallidum subsp. pertenue
Bejel
Lesions in oral cavity
Causative agent of Bejel
T. pallidum subsp. endemicum
Pinta
Ulcerative skin disease
Causative agent of Pinta
T. carateum
Leptospira morphology
Spirochetes with hooks
Leptospira biflexa morphology
With two hooks
Leptospira interrogans
With one hook
Causative agent of human and animal leptospira
Leptospira interrogans
Severe form of leptospirosis
Weil’s disease
Gold standard for leptospirosis
Serological: MAT
Most sensitive specimen for leptospirosis during the early stages
Blood
Can be used for culture on the second week of leptospira infection
Urine
Media for Leptospira culture
Fletchers
EMJH
Stuarts
– 6-8 weeks incubation
Formerly Bedsonia - large virus
Chlamydia
Agent of psittacosis/ornithosis
Chlamydia psittaci
Infective particle of Chlamydia
Elementary bodies
Metabolic particle of Chlamydia
Reticulate bodies
Associated with mild respiratory tract in fections with the TWAR stain
Chlamydia pneumoniae
Chlamydia trachomatis subtype associated with endemic trachoma and inclusion conjunctivitis
A, B, Ba, C
Chlamydia trachomatis subtype associated with venereal infections
D, K
Associated with lymphogranulomatus venereum
Chlamydia trachomatis subtype L1, L2, L3
Eaton’s agent
Mycoplasma pneumoniae
Causative agent for Community-acquired pneumonia
Mycoplasma pneumoniae
Causative agent for primary atypical pneumonia
Mycoplasma pneumoniae
Culture for Rickettsia
Chick embryo
Causative agent of Rocky Mountain Spotted Fever
Rickettsia rickettsii
Causative agent of Rickettsial pox
Rickettsia akari
Causative agent of Epidemic typhus
Rickettsia prowazekii
Causative agent of Sporadic typhus
Rickettsia prowazekii
Causative agent of Brill-Zinsser disease
Rickettsia prowazekii
Causative agent of Murine typhus
Rickettsia typhi
Causative agent of Q fever
Coxiella burnetti
Causative agent of Trench fever
Rochalimea quintana
Rickettsial infections transmitted by lice
Epidemic Typhus
Trench fever
Sporadic typhus
Rickettsial infections transmitted by ticks
RMSF
Q fever
Rickettsial infections transmitted by mites
Rickettsial pox
Scrub typhus
Rickettsial infections transmitted by fleas
Murine typhus
Causative agent of Scrub typhus
Rickettsia tsutsugamushi
Serological test for Mycoplasma
Cold agglutinins – Anti I
Serotest for Rickettsia
Weil Felix reaction
Weil Felix reaction for Rocky Mountain Spotted Fever
OX-2 +
OX-19 +
OX-K -
Weil Felix reaction for Rickettsial pox
OX-2 -
OX-19 -
OX-K -
Weil Felix reaction for Epidemic typhus
OX-2 +
OX-19 +
OX-K -
Weil Felix reaction for Murine typhus
OX-2 +
OX-19 +
OX-K -
Other name for Murine typhus
Endemic typhus
Weil Felix reaction for Scrub typhus
OX-2 -
OX-19 -
OX-K =
Weil Felix reaction for Q fever
OX-2 -
OX-19 -
OX-K -
Weil Felix reaction for Trench fever
OX-2 -
OX-19 -
OX-K -
Clinical manifestation of infection from Bartonella quintana
Trench fever
Clinical manifestation of infection from Bartonella bacilliformis
Carrion’s disease
Clinical manifestation of infection from Bartonella henselae
Cat-scratch disease
Cat-bite disease
Pasteurella
Multicellular phase of fungi
Mold phase
Unicellular phase of fungi
Yeast phase
Dimorphic fungi
Mold at room temp
Yeart at 37C
Infective stage for men
Mold phase at 25C
Diphasic fungi
Mold at 25-37C
Yeast in tissue/in vivo
Basic structure unit that forms the mycelium
Hypha
plural: hyphae
Vegetative portion of the mycelium
Thallus
- grows in or on a substrate and absorbs nutrients
Reproductive portion of mycelium
Aerial
- fruiting bodies that produce the spores
Spores that are contained in saclike ascus
Ascospores
Spores that involve the fusion of two identical cells from same hypha
Zygospores
Spores that involve the fusion of separate cells fron non-identical hyphae
Oospores
Spores contained in a club-shaped basidium
Basidiospores
Spores involved in sexual reproduction
Ascospores
Zygospores
Oospores
Basidiospores
Spores involved in asexual reproduction
Conidia
BlastoconidiaChlamydoconidia
Arthroconidia
Spongiospores
Catenate
Conidia in chains
Echinulate
Rough and spiny conidia
Spores produced singly or multiply in long chains or clasters as conidiosphores
Conidia
Spores that develop as daughter cells that bud off the mother cell
Blastoconidia
Vegetative portion of the mycelium
Thallus
- grows in or on a substrate and absorbs nutrients
Reproductive portion of mycelium
Aerial
- fruiting bodies that produce the spores
Spores that are contained in saclike ascus
Ascospores
Spores that involve the fusion of two identical cells from same hypha
Zygospores
Spores that involve the fusion of separate cells fron non-identical hyphae
Oospores
Spores contained in a club-shaped basidium
Basidiospores
Spores involved in sexual reproduction
Ascospores
Zygospores
Oospores
Basidiospores
Spores involved in asexual reproduction
Conidia
BlastoconidiaChlamydoconidia
Arthroconidia
Spongiospores
Catenate
Conidia in chains
Echinulate
Rough and spiny conidia
Spores produced singly or multiply in long chains or clasters as conidiosphores
Conidia
Spores that develop as daughter cells that bud off the mother cell
Blastoconidia
Thick walled, resistant, resting spored produced by rounding up and enlargement of terminal hyphal cells
Chlamydoconidia
Produced by simple fragmentation of the mycelium
Arthroconidia
Spores contained in a sac produced terminally in sporongophore or aseptate hyphae
Sporangiospore
Unique spore to zygomycetes
Spongiospore
No cellular response by host to this mycoses
Superficial mycoses
Uneven skin color
Ptyriasis / tinea versicolor
Appearance of “spaghetti with meatballs”
Malassezia furfur
Causative agent for black piedra
Piedraia hortae
Causative agent for white piedra
Trichosporon beigelli
Species under cutaneous mycoses
Microsporum (M. canis, M. gymseum, M. audouinii)
Epidermophyton
Trichophyton (T. rubrum, T. mentagophytes, T. tonsurans, T. shoenleinii)
Clinical significance of cutaneous mycoses
Tinea
Tinea capitis
Scalp
Tinea barbae
Beard
Tinea corporis
Body
Tinea cruris
Groin
Tinea inguinum
Nails
Tinea pedis
Foot
Zoophilic Microsporum
Microsporum canis
Anthrophilic Microsporum
Microsporum audouinii
Cutaneous mycoses without microconidia
Epidermophyton floccosum
HIgh red pigment mycoses
Trichophyton rubrum
Favic chandelier, favus T. capitis
Trichophyton shoenleinii
“Balloon forms” aged microconidia
Trichophyton tonsurans
With V shaped penetration in hair baiting test
Trichophyton mentagophytes
Green-yellow fluorescence of ectothrix hairs under Wood’s Lamp
Microsporum canis
Apple-green fluorescence of ectothrix hairs under Wood’s Lamp
Microsporum audouinii
Rose gardener’s disease
Sporotrichosis
Dark, slow-growing fungi
Dematiaceous fungi
Cladosporium type of sporulation
In chains –> tree-like
Acrotheca type of sporulation
With peripheral growth –> test-tube brush
Phialophora type of sporulation
In cluster –> flower / Rafflesia
Most common causative agent of Madura foot
Pseudoallescheria boydii
Is Sporothrix schenckii dimorphic or diphasic?
Dimorphic
- mold at RT
- cigar-shaped yeast cell at 37C
Causative agent of North American Blastomycosis / Gilchrist’s disease
Blastomyces dermatitidis
Causative agent pf South American Blastomycosis
Paracoccidiodes brasiliensis
Causative agent of Darling’s disease
Histoplasma capsulatum
Causative agent of San Joaquin Valley Fever
Coccidioides immitis
Positive for germ tube formation
Candida albicans
Can be saprophytic in oral cavities, GI or vaginal tract
Candida albicans
Causative agent of turolosis/turolopsis
Cryptococcus neoformans
Starburst pattern under gram stain
Cryptococcus neoformans
Incubation of mycoses
30C (25-30C)
Culture heldfor
30 days (21-30days)
Inhibitor on Sabouraud Dextrose Agar
Acidic pH
Resemble lymphocytes in CSF
Cryptococcus neoformans
Mycosel or mycobiotic medium
Sabouraud Dextrose Agar
+ Chlorophenicol (inhibits bacteria)
+ Cyclohexamide (inhibits contaminating mycoses and C. neoformans)
Dermatophyte test medium indicator
Phenol red
Medium for C. neoformans
Birdseed/Nigerseed/Staib’s medium –> phenol oxidase
Medium for B. dermatitidis
Cotoonseed medium
Used to indue sporulation of fungi
Potato flake agar
Recommended for plating medium of mycoses from dairy and other food products
Potato dextrose agar
L-DOPA ferric citrate test
Phenol oxidase
+ bubbles
C. neoformans
