MICROEX2 Organisms Flashcards
Staphylococcus aureus
Staphylococcus aureus
Gram Stain: Gram positive cocci in clusters
Colony: large cream/gold
Media: Sheep Blood, Chocolate, Mannitol Salt, Selective- PEA, CNA, CHROM agar (MRSA)
Infections: TSS, Carbuncles, Septicemia, Osteomyelitis, Food Poisoning
Specimen: Blood, Urine, Wounds
Virulence: Toxins, Agressins (hyalaronidase, lipase, DNAse, Staphylokinase), Coagulase
ID:
Catalase: +
Coagulase: +
Latex Agglutination: +
Hemolysis: Beta
Unique: MRSA
Reservoirs: Human (anterior nares)
Staphylococcus epidermis
Staphylococcus epidermis
Gram Stain: Gram positive cocci in cluster
Colony: large white
Media: Sheep Blood, Chocolate, Mannitol Salt, Selective- PEA, CNA
Infections: Nosocomial Infections
Specimen:
Virulence: Slime layer/biofilm, exotoxin (delta)
ID:
Catalase +
Hemolysis: Gamma
Unique: Opportunistic
Reservoirs: Skin, mucous membranes
Staphylococcus saprophyticus
Staphylococcus saprophyticus
Gram Stain: Gram positive cocci in clusters
Colony: Large white
Media: Sheep Blood, Chocolate, Mannitol Salt, Selective- PEA, CNA
Infections: UTI, pyelonephritis(pregnant women)
Specimen: urine
Virulence: uncertain
ID:
Catalase: +
Novobiocin: +
Hemolysis: Gamma
Unique: Opportunistic
Reservoirs: Skin, Urogenital tract, mucosa
Micrococcus sp.
Micrococcus sp.
Gram Stain: Gram positive cocci in clusters
Colony: Small, yellow
Media: Sheep Blood, Chocolate, Mannitol Salt, Selective- PEA, CNA
Infections: Contaminant
Specimen:
Virulence: Unknown
ID:
Catalase: +
Microdase: +
Hemolysis: Gamma
Unique: Contaminant
Reservoirs: Skin, Mucosa, Oropharynx
Streptococcus agalactia
Streptococcus agalactiae
Gram Stain: gram positive diplococci/ short chains
Colony: large, narrow beta zone
Media: Blood, Chocolate, CNA, PEA, Todd-Hewitt
Infections: Neonatal sepsis, fetal meningitis, UTI
Specimen: Vaginal, blood, CSF
Virulence: Capsule, uncertain
ID:
CAMP: +
Hemolysis: Beta (Lancefield: B)
Unique:
Reservoirs: Female Genitals, upper respiratory, lower gastrointestinal
Streptococcus pyogenes
Streptococcus pyogenes
Gram Stain: gram positive cocci in chains
Colony: grayish, white, large beta zone
Media: blood agar (SXT group A), Chocolate, PEA, CNA
Infections: Scarlet fever, Necrotizing Fasciitis. Pharyngitis, perinasal sinusitis, erysipelas, impetigo, rheumatic fever, glomerulonephritis
Specimen: wound, respiratory tract, urine
Virulence: M-protein, Hemolysins, Streptokinase, SPE,
ID:
PYR: +
Hemolysis: Beta (Lancefield: A)
Unique: Always Clinically Significant
Reservoirs: Skin, Upper Respiratory
Streptococcus pneumonia
Streptococcus pneumonia
Gram Stain: Gram positive diplococci
Colony: small, grey colony w/ dip in center
Media: Blood, Chocolate, PEA, CAN (Special Growth= 5-10% CO2)
Infections: SBE, septicemia, pneumonia, meningitis
Specimen: Blood, transtracheal aspirate, CSF
Virulence: Capsule, IgA protease
ID:
Optochin +
Bile Salt: +
Hemolysis: Alpha
Unique: Sensitive to vancomycin
Reservoirs: nasopharnx
Streptococcus viridans
Streptococcus viridans
- *Gram Stain**: gram positive cocci in chains
- *Colony**: small grey domes
- *Media:** blood, chocolate, PEA, CNA
- *Infections**: Endocarditis, Bacteremia, Meningitis (rare)
- *Specimen:**
- *Virulence:** low virulence
- *ID:** all test negative
- *Hemolysis:** Alpha
- *Unique:**
- *Reservoirs:** Normal flora (oral cavity, gastrointestinal, female genitals)
Enterococcus faecalis
Enterococcus faecalis
- *Gram Stain:** gram positive diplococci/short chains
- *Colony:** small, cream or white
- *Media**: blood, chocolate, CNA, PEA, Enterococcosel agar
- *Infections**: UTI, SBE, nosocomial
- *Specimen:** Urine, Blood
- *Virulence:** Antibiotic Resistance
- *ID:**
Cat: - (psuedocatalase)
PYR +
Bile Esculin +
6.5% salt +
Hemolysis: Alpha, Beta, or Gamma (Lancefield: D)
Unique: Enterococcus Vancomycin Resistance (VRE)
Reservoirs: Female genitals, gastrointestinal tract
Bacillus anthracis
Bacillus anthracis
- *Gram Stain**: large gram positive or gram variable rods (spores)
- *Colony:**
- *Media:** Blood agar (medusa head colonies)
- *Infections**: anthrax, septicemia, Wool Sorters Disease, hemothorax, capillary damage, death, hemmorrhage, edema, meningitis (rare), pneumonia (rare)
- *Specimen:** skin
- *Virulence:** capsule, toxin
- *ID:**
- *Hemolysis:** gamma
- *Unique**: aerobic or facultative anaerobic, “string of pearl” on agar w/ low penicillin, Biosafety 3, Black Eschar at site of spore penitration, 20% mortality (untreated)
- *Reservoirs:** soil
Listeria monocytogenes
Listeria monocytogenes
Gram Stain: short gram positive rod singly or in short chains (can resemble streptococci)
Media: Blood Agar, Selective- Oxford media (black colonies)
Infections: neonatal sepsis, death, meningitis, septic military granulomatosis, ocular listeriosis
Specimen: CSF, blood, placenta, fetal tissue, stool
Virulence: Listeriolysin toxin
ID:
motility (end-over-tumbling)
overnight RT incubation (umbrella)
catalase +
bile esculin +
Hemolysis: beta
Unique: can multiple at low temperatures
Reservoirs: soil, human GI tract, refrigerated food
Lactobacillis sp.
Lactobacillis sp.
Gram Stain: gram postiive rods in chains
Media: Blood, Chocolate, MacConkey (neg), CNA
Infections:
Specimen:
Virulence:
ID:
Hemolysis: alpha
Unique: aerotolerant anaerobe
Reservoirs: Normal flora: human mouth, GI tract and female genitals
Erysipelothrix rhusiopathiae
Erysipelothrix rhusiopathiae
Gram Stain: short gram positive rods
Colony:
Media: Blood agar
Infections: erysipeloid, cellulitis, endocarditis
Specimen:
Virulence:
ID:
Hydrogen Sulfide Production (H2S) +
Hemolysis:
Unique:
Reservoirs: turkey, swine (also rabbits, sheep, birds)
Corynebacterium diphtheriae
Corynebacterium diphtheriae
- *Gram Stain:** irregularly staining gram positive pleomorphic rods (non-spore forming), rods slightly curved or rounded at ends
- *Media:** Tinsdale agar (black colonies w/ brown halo), Cystine-tellyrite BA (black or grey colonies), Loeffler’s medium
- *Infections**: diptheria, myocarditis, chronic peripheral neuritis, ulcers
- *Specimen:**
- *Virulence:** true toxin
- *ID:** biochemical testing, whole fatty acid analysis, cell wall diamino, gene sequencing, toxin using guinea pig lethality, immunodiffuion testing w/ Elek plate, tissue culture, PCR
- *Hemolysis:**
- *Unique:** opportunistic, bacteriophage
- *Reservoirs:** humans, mucous membranes of nose and throat, skin, vagina
Gardenerella
Gardenerella
- *Gram Stain:** pleomorphic gram variable or gram negative rods and coccobacilli
- *Colony**:
- *Media:** Blood, Chocolate, CNA, HBT
- *Infections:** Bacterial vaginosis, UTI
- *Specimen:**
- *Virulence:**
- *ID:**“clue cells” on saline mount
- *Hemolysis:** Beta
- *Unique:**
- *Reservoirs:** Normal flora: vagina
