Neisseria (nasopharynx)

Neisseria Pathogens

Neissera Meningitidis

Neissera Gonorrhoeae

Neisseria

• Gram-negative, bean-shaped, diplococci.

• Do not possess flagella or spores.

• Capsulated and possess pili.

Pathogenic species of Neisseria

require enriched complex media and CO2

Cultural characteristics of Neisseria

• Can grow in blood agar and chocolate agar

• Growth is improved by addition of blood or serum.

• Growth is also improved by incubation in the presence of 2-8% CO2

• Growth temperature is 36-39C and pH ranges of 6-8.

Neisseria Meningitidis

Produces no beta lactamases (Neisseria)

Polysascchride capsule of Neisseria

It is antiphagocytic in nature

Endotoxin of Neisseria Meningitidis

is a lipopolysaccharide (LPS). It induces septic shock by causing release of cytokines.

IgA protease of Neisseria

It cleaves the IgA antibodies present in respiratory mucosa

Pathogenesis of Neisseria

Humans are the only natural hosts

Airborne droplets

Neisseria species/organisms are transmitted by

Nasopharynx, and become transcient flora of the upper respiratory tract

Organs that are colonized by Neisseria

From the nasopharynx

The organism (Neisseria) can enter the bloodstream and spread to meninges and grow in the cerebrospinal fluid.

N. Meningitidis

is the most common cause of meningitis in persons between the ages of 2 and 18 years.

Outbreaks of meningiti

most common in winter and early spring, and favored by close

contact between individuals.

Special condition of Meningococcemia

multiplication of bacteria in the blood stream

Neisseria laboratory diagnosis

It is frequently isolated from samples such as blood and CSF.

Neisseria gram staining

The diagnosis is suggested by the finding of gram negative bacteria bean shaped capsular diplococci

Culture for Neisseria

cultured on blood agar or chocolate agar incubated at 37C in a 5% CO2 atmosphere. No hemolysis

Oxidase test for Neisseria

determines the presence of cytochrome oxydase. It is positive in N. Meningitidis.

N. Meningitidis

Neisseria that ferments manitol

N. Meningitis also

Ferment maltose

Latex agglutination test For Neisseria

detects capsular polyssacaride in the spinal fluid

Penicillin G or sulfonamides

Drugs of choice for Neisseria

Chloramphenicol or third generation cephalosporins

such as cefotaxime or ceftriaxone

recommended for patients who are allergic to penicillin.

Meningococcal vaccine

vaccine for Neisseria that is available, which contains capsular polysaccharide