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36 Cards in this Set
- Front
- Back
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What is the smallest of the small bacteria?
What is their distinguishing feature? |
Mycoplasma
Identifier: lack a cell wall |
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What growth conditions are necessary for mycoplasma?
-Media -Incubation |
Media must contain:
-serum (for protein) -yeast Incubation: -Increased CO2 -Up to 1 month |
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How is mycoplasma identified?
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Stereomicroscope -> fried egg morphology of tiny colonies.
DIENES STAIN -> short blue bacilli (GS does not work) -Immunologic ID is best. |
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most pathogenic member of mycoplasma:
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Mycoplasma pneumoniae
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What disease does M. pneumoniae cause?
What antibiotic treats this? Treatment? |
-Walking pneumonia in young adults
-Erythromycin |
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What are 3 methods for detecting M. pneumoniae?
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1. EIA
2. Cold agglutinins (50%) 3. Nucleic acid probe I.D. |
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what are 4 species of mycoplasma other than pneumoniae?
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M. hominis
M. genitalium M. fermentens M. salivarium |
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What species of Mycoplasma are genital pathogens?
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M. hominis
M. genitalium |
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Where is M. fermentens found?
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Vagina
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Where is M. salivarium normal flora?
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In the oral cavity.
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name of genital tract pathogen related to mycoplasma:
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ureaplasma urealyticum
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Essence of L-forms
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lack a cell wall but due to a condition that caused it:
1. high conc. of penicillin 2. high conc. of salt |
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type of bacteria that easily becomes
L-form: what does it cause? |
Streptobacillus moniliformis
causes rat bite fever |
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How many types of legionella are there?
Most common? Commonly found in: |
about 40 species
L. pneumophila Water |
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What does legionella pneumophila mean?
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Little legions of lung-loving bacteria
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What disease is caused by l. pneumophila?
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severe Acute Respiratory disease
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How is L. pneumoniphila transmitted?
Who is it most commonly seen in? |
Inhalation/aspiration of H2O
Middle aged men - they smoke |
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Why was L. pneumophila hard to find?
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It doesn't stain! they could never find it in all those samples
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How does a L. pneumophila infection progress re: sx?
What is it treated with? |
-Starts w/ flu-like symptoms, high fever develops, then into
Lobar pneumonia w much sputum. -Treat with erythromycin Erythromcyin |
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What is Pontiac fever?
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A milder form of Legionnaire's disease caused by an antigenic variant.
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what specimen is tested for L. pneumophila?
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sputum; can be hard to get, so induce it.
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-What growth factor is needed for culturing Legionella?
-What agar is used? |
-L-cysteine.
-Agar: BCYE - buffered charcoal yeast extract media |
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what are the cultural (growth) characteristics of L. pneumophila?
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1st inoculate the plain BCYE: shouldn't see growth. Allows presumptive I.D.
2nd inoculate BCYE + cystine; then should see growth. Growth requires 3-4 days and results in ground glass appearance of colonies |
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Name 3 methods for ID of Legionella:
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1. Growth on BCYE+cystine
2. Flourescent Ab Test a. Direct (specimen/culture) b. Indirect (serum - both conval. and acute phase) 3. Nucleic acid probes - PCR |
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Legionella is
Catalase: Oxidase; |
Cat +
Oxi weakly + |
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chemical component that causes Acid fastness:
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mycolic acid
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What genus is acid fast bacilli?
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Mycobacterium
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What 5 types of specimens can be tested for mycobacterium?
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1. Sputum, bronchoalveolar lavage, bronchial washings.
2. Gastric secretions (neutralize imm.) 3. Urine 4. Tissue, CSF, Blood 5. Skin First morning specimens always |
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what are the OSHA requirements for mycobacterium processing
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1. neg air flow room -
biosafety level 3 room 2. Biolog. safety cabinet 3. Wear gowns, gloves, respirators 4. Skin test personnel ev. 6 months |
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whats the most important, first test you must do when testing for mycobacterium?
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DIRECT SMEAR - growth takes so long, this is the best way for fast info.
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what are 2 types of direct smears you can do for mycobacterium:
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-Acid fast: Kinyoun or Ziehl-neelson; must examine at least 15 min or 300 fields; easy to miss the bug on a TB smear.
-Flourescent: easier, but background/garbage also messes up |
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How to process a gastric or sputum culture for mycobacterium:
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1. NALC NAOH - digest mucous, decontaminate specimen, get rid of normal oral flora.
or 2. Trisodium phosphate + benzalkonium chloride; but #1 is better |
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How to process a urine specimen for mycobacterium:
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concentrate it by centrifugin
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What media is used for isolating Mycobacterium?
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-Lowenstein Jensen
-Middlebrook -Broth AND Agar, can add antibiotics. |
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What incubation conditions apply to Mycobacterium cult?
(skin, other)(temp and time) |
Skin: 30 C
All else: 37 C Increased CO2 at least 8 weeks before calling neg! |
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What 3 things should be done if specimen with suspected mycobacterium grows?
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1. Check for acid fastness
2. check colony morph; if unpigment, expose to light, reincubate. 3. record time required for growth |
