Infectious Diseases and Microbiology - Meningitis ( Neisseria meningitidis)

Infectious Diseases and Microbiology - Meningitis ( Neisseria meningitidis) 
There are thirteen serogroups of the Gram-negative diplococcus Neisseria meningitidis, the most significant of which are A, B, C, Y, and W135 according to the polysaccharide capsule.

N meningitidis  virus infects humans. Respiratory droplets are the main vectors that spread the disease.
In close quarters, such dorms or military barracks, the concoction of carriers and vulnerable individuals might lead to an outbreak.

The nasal passages serve as the entrance point. Organisms can enter the bloodstream from the nasopharynx (meningococcemia).
The most common consequence of meningococcemia is meningitis. Meningococcemia is characterized by the presence of ecchymoses and widespread petechiae. Disseminated intravascular coagulation (DIC) in extreme instances is a real possibility.

Endotoxin (lipooligosaccharide), pili, IgA1 protease, and an antiphagocytic polysaccharide capsule are major virulence factors. In the conventional pathway of immunological clearance, complement plays a key role, as it does with N gonorrhoeae. Dissemination is more likely to occur in those who have complement deficits.

Cerebrospinal fluid testing for N meningitidis include direct Gram stains and latex agglutination.
Blood or chocolate agar can be used to cultivate Diagnosis N meningitidis.

Treatment is usually successful with penicillin or third-generation cephalosporins. It is possible to get an injection that protects against serogroups A, C, Y, and W135. The present vaccination does not contain the B serogroup polysaccharide since it is an inadequate immunogen. Serogroup B accounts for a huge proportion of these instances. People at high risk who have had close contact with an index case can be treated with rifampin for chemotherapy prevention.