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5 Cards in this Set
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- Back
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Bordetella pertussis
(parapertussis - same but sometimes more mild) |
Small, aerobic, Gram neg., fastidious (chocolate agar reqd.)
Transmitted via droplets of resp. tract secretions, high attack rate if not immunized (very high attack rate in infants) Disease (3 stages:) 1. Catarrhal stage (7-10 days), dry cough, very contagious 2. Paroxysmal stage (2 wks), intense coughing (whoops) vomiting, hernia, hemorrhaging, phenmothorax, transmission goes down. High WBC count. 3. Convalescent stage (4wks): secondary bacterial infection (pneumonia), encephalopathy, seizures Virulence Factors: 1. Pertussis toxin: ADP ribosylates Gi, permanently turning off (AB toxin) 2. Filamentous hemagglutinin (FHA): binds to host receptor (mostly on ciliated cells in airways. 3. Invasive AC toxin: inhibits chemotaxis, phagocytic activity, works like anthrax EF (calmodulin-dependent AC) 4. Lethal toxin: local damage, SM contraction 5. Tracheal cytotoxin - inhibits DNA replication and stim. release of IL-1 (fever) 6. Pertactin - afimbrial adhesin Tx: Erythromycin, azithromycin DTaP vaccine |
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Haeophilus influenzae
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Small, gram neg., capsule/no capsule, colonizes nasopharynx naturally
Can only grow on chocolate agar Type B capsule (PRP) = most virulent -Meningitis (peds. mostly) -Septic arthritis -Acute Epiglottitis - block airway NTHI (non-typable) strands: -Respiratory Tract infections in COPD (opportunistic) -Otitis media -Cellulitis Tx: Cefotaxime or ceftriaxone Prophylaxis: rifampin |
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How to diagnose Haeophilus influenzae
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-Gram stain of CSF
-Capsular Ag test by countercurrent electrophoresis -Particle latex agglutination test -Culture of CSF on chocolate agar whatever the hell that stuff means |
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Hib vaccine
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For all kids under 5 y/o
Everyone that is immunocompromised or on long-term steroids People with no spleen protein/polysaccharide (PRP) conjugate |
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Haemophilus ducreyi
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STD: chancroid. Bacteria enter abrasions and a single painful bleeding ulcer forms. (chancres by syphilis are not painful)
Test w/ gram-stain and culture Tx: azithromycin or ceftriaxone |
