Unit #4

Bacillus species

spore forming and catalase positive

Listeria Monocytogenes

regularly shaped, non-spore forming, catalase negative

Erysipelothrix rhusiopathiae and Lactobacillus sp. and Gardnerella vaginalis

regularly shaped, non-spore forming, catalase negative

Corynebacterium species

irregularly shaped, non-spore forming, catalase positive

KOH Threat Test

GNR have viscous thread. GPR have no thread

Protective Agent (PA)

bacillus anthracis exotoxin that binds and opens

Edema Factor (EF)

bacillus anthracis exotoxin that has fluid accumulation

Lethal Factor (LF)

bacillus anthracis exotoxin that causes cell death

Bacillus anthracis morphology

non-hemolytic, large, grey flat colonies with irregular margins. Non-motile

Bacillus cerus Morphology

beta hemolytic, but otherwise the same as B. anthracis

Listeria Monocytogenes

widespread in enviornment, food contamination, can grow at 4 C

Listeria Monocytogenes Morphology

ambient CO2, beta hemolytic, small, round, smooth, translucent

Catalse Test

differentiates Group B strep from listeria monocytogenes (positive)

Erysipelothrix Rhusiopathiae

widespread in nature. often zoonotic

Erysipelothrix Rhusiopathiae Morphology

non-hemolytic pinpoint colonies after 24 hours. 48-72 hours small alpha hemolytic. H2S+ and non-motile

Gardnerella species Morphology

non-hemolytic pinpoint colonies on BAP. beta hemolytic small opaque colonies on HBT

Corynebacterium diphtheria

causes diphtheria

Corynebacterium jekeium

opportunistic pathogen (septicemia, meningitis, and pulmonary disease)

Corynebacterium urealyticum

urinary tract infections

Corynebacterium Morphology

BAP in ambient air or CO2. Dry tiny, grey, white irregular colonies. palisade in gram stain

Nocardia and Streptomyces

branching and filamentous GPR

Mycobacterium species

slender, slightly curved or straight, rod-shaped. Strongly acid-fast (high level of mycolic acid)

Aerobic Gram Negative Dipococci

Neisseria species and Moraxella

Transferrin Receptor

virulence factor of gram negative diplococci

Porin (Por)

cell membrane protein 1. opens channel

Opacity (Opa)

cell membrane protein 2. facilitates attachment

Reduction Modified Protein (Rmp)

cell membrane protein 3. cell death and IgG

IgA Protease

increased invasiveness by cleaving IgA on mucosal surfaces

DNase

tests ability to hydrolyze DNA with DNase. methyl green halo indicates property

Butyrate Esterase

tributryin hydrolyzes substrate in presence of butyrate esterase. Blue to green is positive. Usually screens moraxella

Neisseria Gonorrhoeae Growth

Requires ChOC or MTM agar. Capnophilic

MTM Agar

choc agar that contains vancomycin, colistin, nystatin, and trimethoprim

Neisseria Gonorrhoeae Specimen Collection and Transport

must be cultured immediately. very sensitive to cold so transport at room temp. May dry. Use Dacron or Rayon swabs

Delayed Transport of Neisseria Gonorrhoeae

Use Jembec, transgrow, or Gono-Pak if needing to transport longer

Vancomycin

inhibits gram positive

Colistin

inhibits gram negative

Nystain

inhibits yeast

Trimethoprim

inhibits proteus/swarming

Penicllin disk

antibiotic causes GNR to elongate making them easier to identify

Neisseria Gonorrhoeae Diagnosis Male vs Female

Male its diagnostic women it is not due to commensal flora

Neisseria Gonorrhoea Molecular Testing

Allows for simultaneous detection of N. Gonorrheae and Chlamydia

Neisseria Gonorrhoeae Biochem Tests

Glucose Positive. PRO Positive. Oxidase +

Neisseria Gonorrhoeae Reporting

Must be reported within 7 days to state health department

Neisseria meningitidis

has 12 serotypes with A, B, C, W-135, and Y causing most disease

Neisseria Meningitids Biochem Tests

Glucose and Maltose Positive. Oxidase +. PRO variable and GLUT positive

Neisseria Meningitidis Reporting

must be immediately reported to state health department. CDC recommends biosafety level 2 cabinet

Neisseria Lactamica Biochem Tests

Glucose, Maltose, and Lactose Positive. Oxidase +. BGAL Positive.

Moraxella Catarrhalis

normal flora of upper respiratory tract. opportunistic pathogen in child and eledery. Causes maxillary snusitis and otitis media

Moraxella Catarrhalis

hockey puck morphology and has pink/salmon color with age. Grows on BAP/CHOC

Moraxella Catarrhalis Biochem Tests

Oxidase +. DNase Positive. Nitrate Postive. Butyrate Esterase Positive. IB Positive. Carb Negative

Haemophilus species

normal flora of upper respiratory tract that are opportunistic. Except H. ducreyi

Haemophilus sp Virulence Factors

Capsule is most important.

Exogenous Haemophilus

H. influeznae type B and H. ducreyi

Haemophilus Growth Requirements

capnophilic. Require V factor and X factor

V factor

NAD (nicotinamide-adenine dinucleatide). Heat labile. Present in RBC, yeast, and potato

X factor

hemin. heat stable. present in RBC lysis

Haemophilus sp gram stain

May have to leave safranin on longer or use carbolfuschin instead

Haemophilus influenzae Clinical Significance

Respiratory tract infection (secondary to viral), meninigits, otitis media, and conjunctivitis

Haemohilus ducreyi Clinical Significance

soft chancre (STD), chancroid, genital ulcers, lesions

Haemophilus sp identification

Very tiny with or without capusle. Arranged in school of fish or railroad tracks

Haemophilus Specimen Handling

setup culture immediately. Requires CHOC, and incubate in 5-10% CO2 moist enviornment

Horse/Rabbit Blood Agar and RTF Medium with Sheep Blood

Some Haemophilus species will show beta hemolysis on these plates

Satellitism

Haemophilus can grow on BAP, if around organism that produces NAD (V factor)

Haemophilus influenzae Identification

Catalse +, Oxidase +, Hemolysis =, X - none V - none XV - growth

Haemophilus haemolyticus Identification

Catalse +, Oxidase +, Hemolysis +, X - None V - none XV - growth

Haemophilus parainfluenzae Identification

Catalse V, Oxidase +, Hemolysis =, X - None V - Growth - XV - Growth

Haemophilus parahaemolyticus Identification

Catalse +, Oxidase +, Hemolysis +, X - None V - Growth XV - Growth

Haemophilus ducreyi Identification

Catalse =, Oxidase =, Hemolysis V, X - Growth V - None XV - Growth

Prophyrin Test

determines if organism can make its own X factor with product pophobilinogen and porphyrin. Shine UV light and look for red/oragne color change

Porphyrin Test Advantage and Disadvantage

X factor is not needed and no carryover contamination. Uses negative result to Id