Gram negative cocci

The 5 genera of the family Neisseriaceae

The 5 genera of the family Neisseriaceae

Neisseria

Moraxella

Kingella

Oligella

Acinetobacter

Two main Genus neisserria pathogens

Neisseria Meningitidis (Meningococcus)

Neisseria Gonorrhoeae (Gonococcus)

Others:N.lactamica, N.mucosa, N.Polysacchareae, N.subflava, N.sicca

General Characteristics of the genus neisseria

Kidney/bean shaped diplococci

Non motile

Non sporing

Enriched medium

35-37 degree Celsius

Typical G- cell wall

Capsule and pili may be present

N.Meningitidis portal of entry

Respiratory tract

N Gonorrhoeae portal of entry

Genital tract

N meningitidis Pathogenesis,typical disease and treatment

Pyogenic , meningitis and meningococcemia , Penicillin G

N Gonorrhoeae Pathogenesis , typical disease and treatment

Pyogenic

local (Gonorrhoeae- urethritis/cervicitis) - ceftriaxone plus doxycycline(chlamydia trachomatis coinfection)

Ascending (pelvic inflammatory disease) - cefoxitin plus doxycycline

Disseminated (Disseminated gonococcal infection) - ceftriaxone

Neonatal (conjunctivitis/ophthalmia neonatorum) - ceftriaxone with silver nitrate or erythromycin for prevention

N meningitidis antigenicity

13 serotypes

PCR are used for serotyping

Serotyping is based of the antigenic variation of capsular polysaccharide

Common:A,B,C,W-135,Y

Others: DHIK,L,29E,X,Z

(Serogroup - slide agglutination)

N meningitidis

Virulence factors

Polysaccharide capsule :resists phagocytosis by PMNs

Endotoxin(LPS): fever , shock and o

Immunoglobulin A protease

Identify

Neisseria

Identify

Meningococcemia

Normal CSF Glucose and protein levels

CSF Glucose:

Identify

Purulent urethral discharge caused by Neisseria Gonorrhoeae

Identify

Neonatal conjunctivitis(ophthalmia neonatorum ).

Purulent exudate on lower right eyelid(chlamydia trachomatis)

Identify

Neisseria Gonorrhoeae gram stain

Bean shaped gram negative diplococci within a neutrophil

Complications of N Gonorrhoeae

1. Genital Gonorrhoeae

2. Abscess of the Bartholins and Skenes glands

3. Proctitis (renal inflammation):symptomatic in homosexual males

3. PIDs :

Salipingitis,pelvic peritonitis, ectopic pregnancy, infertility

4. Fitz Hugh Curtis syndrome

5. Pharyngitis

6. GADS- gono arthritis dermatitis syndrome

7. Disseminated gonococcal infection (DGI).

   arthritis,meningitis,endocarditis

8. Vulvovaginitis in girls

9. Conjunctivitis (ophthalmia neonatorum)

Specimen for lab diagnosis