Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
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- Bacterial illness caused by Neisseria meningitidis
- Several forms of illness may occur
- Mild meningococcemia
- Overwhelming meningococcal sepsis
- Meningococcal meningitis
- Chronic/occult meningococcemia
- Septic arthritis
- Acquired from close contact with an infected individual or an asymptomatic carrier
- Intimate kissing and cigarette smoking are independent risk factors.
- N. meningitidis:
- Serotypes A, B, C, D, H, I, K, L, X, Y, Z, 29E, and W135
- Serotype B is most common in US
- Majority of infections caused by A, B, C, X, Y, and W135
- Bacteria attach to and enter nasopharyngeal epithelial cells.
- Bacteria spread from the nasopharynx through the bloodstream via entry of vascular endothelium.
- Most circulating meningococci are eliminated by the spleen.
- Meningococci produce an endotoxin (lipooligosaccharide):
- Involved in pathogenesis of the skin, adrenal manifestations, and vascular collapse
- Human oropharynx/nasopharynx is the only reservoir.
- Carrier usually has developed immunity to serotype-specific antibody (not immune to all serotypes):
- Age <5 yr: 1% carrier rate
- Age 20–40 yr: 30–40% carrier rate
- Lower rate of immunity in children, which is reflected by the higher rates of infection
- Most common in fall and spring
- Increased incidence in military recruits and close living conditions
- Epidemics—ages 5–9 yr most/earliest affected