Term
Staphylococcus Saprophyticus
SBA with Furazolidone and Novobiocin |
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Definition
-Susceptible to furazolidone (large inhibition zone around FX)
-Saprophyticus is one of several Strep species resistant to Novobiocin (C-)
-Appears gamma hemolytic |
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Term
Staphylococcus Saprophyticus
Infection types, populations affected |
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Definition
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Term
Staphylococcus Saprophyticus
API Staph ID Panel, pt. 1/2
(red=neg, yellow=pos) |
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Definition
| CHO-/MNE-/TRE+/MEL-/GLU+/MAL+/MAN+/FRU+/LAC+/XLT- |
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Term
Staphylococcus Saprophyticus
API Staph ID Panel, pt. 2/2 |
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Definition
| VP+/SAC+/ADH-/NIT-/RAF-/MDG-/URE+/PAL+/XYL-/NAG- |
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Term
S. Saprophyticus
-How to uniquely ID with API |
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Definition
-API biocode shows possible S. Sapro, S. Warneri, or S. Homonis
-Saprophyticus is the only of that group that is resistant to Novobiocin |
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Term
Non-Pathogenic Lactobacilli (Vaginal Microbiota)
Gram Stain Morphology |
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Definition
| Gram positive bacilli in single, pair, or short chain |
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Term
Vaginal Microbiota
SBA Colony Morphology |
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Definition
| Small, round, brownish with bright yellow center, appears alpha-hemolytic |
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Term
Vaginal Microbiota
Gram stained smear of vaginal specimen |
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Definition
Specimen has large endothelial cells
Gram Positive ones are normal (lactobacilli) |
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Term
Gardnerella Vaginalis
Type of infection? |
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Definition
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Term
G. Vaginalis
Gram stained vaginal smear |
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Definition
| Gram negative bacilli and coccobacilli associated with large endothelial cells |
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Term
G. Vaginalis
on CNA blood agar? |
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Definition
NOTE: caprophytic (req. 5-7% CO2)
Colonies are very small, best observed in areas of confluent growth |
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Term
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Definition
NOTE: HBT= Human Blood Bilayer-Tween medium
Gardnerella req. 35-37C and 5-7% CO2
Small, B-Hemolytic colonies |
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Term
G. Vaginalis
any other media? |
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Definition
Rapid carb-utilization (technique used for Neisseria identification)
Produces acid from GLUC/MALT
not from Mannitol
Highly hippurate hydrolysis + (black) |
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Term
T. Pallidum
Incubation period |
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Definition
50% of infex's contact can escape infection, as few as 57 orgs needed to infect
Lasts from 3-90 days, mean=3 weeks |
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Term
T. Pallidum
Primary Syphilis |
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Definition
Lesion (chancre; not always present)=Clean/smooth base, firm raised edge
Usually painless, slightly tender
Scant exudate unless 2* infexn in chancre, heals in 3-6 wks
Multiple chancres can occur in immunodeficient
Enlarged regional LN's
Confirmatory Lab test for 1* is darkfield microscopy w/ spirochete presence, as Nontreponemal tests are false (-) in 10-30% of syphilis cases |
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Term
T. Pallidum
Secondary Syphilis |
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Definition
Organisms are most numerous
2-8 weeks after chancre's appearance
Most dramatic: widespread rash (feet/hands=maculopapular or pustular), non-vesicular
Moist areas: gray-white plaque (condylomata lata) high in spirochete#
Darkfield microscopy or immunofluorescence
Systemic: lymphadenopathy, fever, malaise, any organ could be involved (hepatitis, keratitis, osteitis)
CNS infexn happens in this phase= Meningismus and headache, also aseptic meningitis can happen
No clear line b/t 1* and 2*, as 1* chancre can be present when rash develops |
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Term
T. Pallidum
Latent Syphilis |
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Definition
Follows 2*, org is subclinical (not dormant)
Early latent= 4 year pd, relapses occur and patient is infex's during them
90% relapses in first year
Disease presence can be serologically determined in this phase. |
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Term
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Definition
| Complications: CNS disease, CV abnorm's, tumors (gummas- occur in any organ) |
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Term
T. Pallidum
Test for late neurosyphilis |
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Definition
VDRL assay of CSF that shows elevated proteins and decreased glucose
--org is utilizing your brain's fuel |
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Term
T. Pallidum
Types of syphilis/characteristics |
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Definition
CV: 10% of untreated cases, inflamm of aorta (syphilitic aortitis). Aortic aneurism/dilation of aortic ring= not enough blood through aortic valve
Late "benign" syphilis: 15% of untreated, gummas= most common complication, can destroy surrounding tissue as it enlarges. VDRL's insensitivity means must use FTA-ABS (fluorescent treponemal AB absorption)
Congenital: many fetuses die. Survivors have lesions of 2* syph b/c no 1* entry site. Abnorm's of bone and teeth. Penicillin therapy for mother, baby's VDRL should be norm after 6 months and FTA-ABS w/in a year. |
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Term
Serologic tests of Syphilis
2 types, tests filed under each type, and characteristics |
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Definition
Non-Treponemal: includes VDRL and RPR. Tests for an antibody to cardiolipin (tissue lipid). FLAW: In late syphilis, these appear very low or negative. Also, affected by antitreponemal therapy
Treponemal: Uses specific treponemal antigens. Still very high in late, unlike non-treponemal. Incl FTA-ABS, TPHA, and TPI. FTA-ABS is very specific, but can produce false pos in treponeme other than syphilis; detects IgM or IgG. FTA-ABS is the cheapest of the 3, and replaced TPI |
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Term
Serologic tests of Syphilis
Provisional and Investigative Tests |
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Definition
Enzyme/particle agglutination immunoassays becoming more frequently used.
Also: Western Blot has 92% sens in symptomatic infants, and 83% in asymptomatic (looking for 47 kD specific ag). Immunoblots are used as confirmatory tests |
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Term
Mobiluncus
Etiology: Condition, People affected |
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Definition
Bacterial Vaginosis (member in nonspecific vaginitis)
Women |
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Term
Mobiluncus
Bacterial Characteristics (Gram, Aer/An, Appearance, spores) |
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Definition
Variable Gram Negative stain (GP wall char's), Gull-wing Rod in singles or pairs, motile, non-spore forming
Anaerobe
Lacking of outer membrane (typical of G+), yet young cultures stain gram variable; older stain gram neg |
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Term
| Bacterial strains associated with bacterial vaginosis |
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Definition
Gardnerella vaginalis
Mycoplasma hominus
Mobiluncus Spp
Peptostreptococcus anaerobius, P. asaccharolyticus, P. magnus |
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Term
| Typical characteristics of bacteria associated with bacterial vaginosis |
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Definition
Anaerobic cocci
Anaerobic Gram pos rods (eg. Propionibacterium)
=Synergistic infection |
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Term
| Diagnostic criteria of bacterial vaginosis |
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Definition
1. thin but profuse discharge
2. pH>4.5
3. fishy odor (esp. upon adding 10% KOH)
4. Clue Cells: squamous epithelial cells w/ many small rods adherent to surface (wet mount/Gram) |
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Term
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Definition
Grow on many non-selective media (ABA, CHOC)
2-4 days, colonies are 2-4 mm in diameter, colorless, smooth, flat, sometimes spreading appearance |
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Term
| How to differentiate Mobiluncus from M. curtisii and M. mulieris |
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Definition
NEG) Indole and Catalase
POS) Growth in Arg presence, Hippurate hydrolysis
-->(Difficult to differentiate) |
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Term
Chlamydia Trachomatis
Direct detection in clinical specimens: methods? |
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Definition
Right-Giemsa (or Gimenez)
Inclusions in cytoplasm of epithelial cells are perinuclear, must distinguish from fragmented nuclei. |
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Term
Chlamydia Trachomatis
Frequency of inclusion detection for each kind of specimen |
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Definition
Inclusions detected...
MOST in neotatal conjunctivitis
Less in adult conjunctivitis/trachoma
LEAST in urethritis and cervicitis |
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Term
Chlamydia Trachomatis
Antigen detection technique/plate appearance in a positive result |
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Definition
Uses immunofluorescence/enzyme immunoassay
Evans blue-->Cells stain bright red, black background
Antigens fluoresce yellow/bright green
McCoy cell monolayer treated with cyclohexamide, fluorescein-conjugated monoclonal antibody. All black, sparse tiny green dots=intracytoplasmic inclusion |
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Term
Chlamydia Trachomatis
Nucleic Acid detection tests, names, sensitivity |
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Definition
1st: Gen-Probe, DNA probe agains rRNA
(sens~80-95% dep. on population)
2nd: Amplification of any kind~ more sens. than hybridization (like Gen-Probe)
MOST COMMON NA TESTS: PCR, Strand Displacement Amplification, Transcription-Mediated Amplification |
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Term
Chlamydia Trachomatis
problem with NA detection (amplification) |
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Definition
| Cost--all are more sensitive than cheaper methods, and can detect in urine, but used less |
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Term
Chlamydia Trachomatis
When are screens performed? Interpretation? |
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Definition
| Screening is typically done in asymptomatic phase, Inconclusive tests are up to the lab director |
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Term
Neisseria gonorrhoeae
Gram stain taken from male with these symptoms (2); appearance |
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Definition
Gonococcal urethritis, and subsequent discharge
Intracellular diplococci within pale neutrophils |
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Term
Neisseria gonorrhoeae
Growth requirements, typical medium (describe) |
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Definition
35-37 C @ 5% CO2
MTM (modified Thayer-Martin) Agar.
=Chocolate-agar contains vancomycin (GP), colistin (GN), and nystatin (Fungal)
*parentheses=orgs inhibited by each |
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Term
Neisseria gonorrhoeae
Colony characteristics |
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Definition
on MTM (looks like a more red CHOC)
Colonies are somewhat large, yellowish brown, glossy |
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Term
Neisseria gonorrhoeae
CTA--> What is it? What does N. gonorrhoeae look like? |
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Definition
Cysteine Tryptic Agar
Semisolid agar to ID Neisseria Spp.; differentiates by sugars utilized; CTA-(Glucose, Maltose, Sucrose, Lactose, Control)
N. Gono-->ONLY UTILIZES GLUCOSE (phenol red indicator turns yellow) |
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Term
Neisseria gonorrhoeae
GONOCHEK II test principles, result appearance/interpretation |
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Definition
3 chromogenic substrates to detect glycosidase and aminopeptidase activity in Neisseria (Meningitidis, lactamica, gonorrhoeae)
BLUE->Lactamica (B-galactoside hydrolysis)
YELLOW->Meningitidis (gamma-glutamyl-p-nitroanilide hydrolysis)
PINK/RED->Gonorrhoeae (prolyl-B-naphthylamide hydrolysis)
COLORLESS-> presump. Moraxella Catarrhalis |
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Term
Haemophilus ducreyi
Disease? Characteristics of this disease? |
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Definition
| Chancroid, may resemble syphilis chancres, but are painful and soft (syphilis=painless/hardened), can culture the bacteria from these lesions |
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Term
Bacillus anthracis
Gram stain/Malachite Green spore stain |
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Definition
relatively large Gram positive bacilli with terminal endospores that don't swell the cell.
Spore stain: ovoid spores (no swelling), bamboo arrangement (also in Gram) |
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Term
| Signs/Symptoms of GI Anthrax? |
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Definition
| Lesions of cecum and adjacent areas of bowel cause abdominal pain, bloody diarrhea and hematemesis (blood vomit) |
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Term
Bacillus anthracis
on SBA? |
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Definition
| Offwhite, dull, nonhemolytic, comma-shaped outgrowths ("Medusa-head Colonies") |
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Term
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Definition
| (more frequently isolated bacillus in lab); unlike B. anthracis, is B-hemolytic, motile, and B-lactamase positive |
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Term
Yersinia pestis
Presentation on humans |
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Definition
| Hematogenous spread can cause IV coagulation-->endotoxic shoc-->small hemorrhages on skin |
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Term
Yersinia pestis
Gram stain |
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Definition
short, plump gram-neg rods
bipolar stain shows pale center, characteristic "safety-pin" appearance |
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Term
Yersinia pestis
Wright stain-- done on what kind of sample? |
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Definition
| Peripheral blood smear; shows dark blue bacteria, light blue PMNs with purple nuclei, and tan RBCs |
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Term
Yersinia pestis
On SBA- time to culture, colony morphology |
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Definition
48-72 hours
grey-white to slight yellow (looks blue in book), opaque, raised, irregular "fried-egg" shape. May have "hammered copper" shiny surface. gamma-hemolytic |
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Term
Listeria monocytogenes
Gram stain morphology |
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Definition
| short, gram positive bacilli (in picture, kinda looks like clumped cocci) |
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Term
Listeria monocytogenes
SBA (growth requirements, hemolytic patterns) |
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Definition
72 hours @ 35-37 C and 5% CO2
B-hemolytic, but not very visible after first 24 hours. Even after 48 hours, hemolysis barely extends from colony margin, and is not much more evident than the 48 hour sample |
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Term
Listeria monocytogenes
Bile-esculin agar characteristics, appearance, and interpretation |
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Definition
When not inoculated, medium is golden brown
Like enterococci, Listeria monocytogenes hydrolyzes esculin in the presence of 40% bile
Medium turns black |
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Term
Francisella tularensis
Disease? Characteristics? |
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Definition
Tularemia; Inguinal lymphadenopathy, abdominal distension, watery diarrhea
Similar to typhoid
Meningitis-associated (low gluc/high protein near brain) |
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Term
F. tularensis
Biosafety level?
Isolation obtained from? |
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Definition
BSL-3, prior it was 2 (bioterror threat)
Take from primary ulcer, LN aspirate or biopsy, sputum, BM, and tissue biopsy.
Cultures isolated from typhoidal, pneumonic, oropharyngeal |
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Term
F. tularensis
Growth method? |
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Definition
BACTEC- takes 7-9 days to grow
MTM agar/CHOC: enriched with IsoVitalex
Buffered Charcoal Yeast Extract (BCYE) Agar: -->Used for legionella; can support fastidious org's
Requires 5% CO2 (caprophilic), 2-5 days at 35-37 C. |
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Term
F. tularensis
ID method vs other Francisella? |
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Definition
| PCR, 16s rRNA sequencing, DNA probe hybridization, EIA using monoclonal LPS subsp. tularensis. |
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Term
F. tularensis
Serologic tests |
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Definition
| Hard to diagnose til late in the course, so serologic tests are BEST FOR DIAGNOSIS. (tube agglutination, TA) |
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Term
Rickettsia
Infected organs
Transmission route |
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Definition
Symptomatic= Skin, Lung, Brain
obligate intracellular pathogen
Tx: Arthropod Bite
Cats/opossums |
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Term
Coxiella burnetii
Transmission/infection type |
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Definition
obligate intracellular pathogen
infected milk or aerosols |
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Term
| Scrub typhus: t/f endemic in USA |
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Definition
False-- Orientia tsutsugamushi (Cent/East Asia?)
seen w/ 1* eschar- seen rarely with Rocky Mtn Spotted Fever |
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