Meningococcal Meningitis

Meningococcal meningitis is caused by Neisseria meningitidis of groups A, B, C, Y, and W-135

-Neisseria meningitidis is a catalase- and oxidase-positive, gram-negative aerobic diplococcus with a polysaccharide capsule 

-Most commonly, meningococci asymptomatically colonize the nasopharynx

Symptoms & Signs

-Fever, chills, headache, nausea, vomiting, confusion, delirium, seizures, positive Kernig sign (pain in the hamstrings upon extension of the knee with the hip at 90-degree flexion), positive Brudzinski sign ( flexion of the knee in response to flexion of the neck), a petechial rash (Memory aid: Neck Brace, flexion of the neck produces flexion of the knee in Brudzinski sign) 

Diagnosis 

-Diagnosis is confirmed by the presence of gram-negative intracellular diplococci in the culture of normally sterile body fluids 

-All children suspected of meningococcemia should have a lumbar puncture.

Treatment 

-Antibiotic therapy should not be delayed waiting for performance of lumbar puncture. 

-Common antibiotics used: penicillin G, ceftriaxone, cefotaxime, vancomycin, chloramphenicol  

Prevention

Vaccination: Polysaccharide-based and conjugate vaccines

Chemoprophylaxis to eliminate nasopharyngeal carriage of meningococci: Rifampin, ciprofloxacin, ceftriaxone 

-Rifampin may stain a patient’s tears, contact lenses, sweat, and urine orange

-Rifampin should not be given to pregnant women