Neisseria gonorrhoeae and N. meningitidis are pathogenic Neisseria species. N. gonorrhoeae causes gonorrhea, transmitted sexually or from mother to child. It infects the urethra, cervix, and other sites. Without treatment, it can spread and cause complications like pelvic inflammatory disease. N. meningitidis causes meningitis, transmitted through airborne droplets. It infects the nasopharynx and can spread to the blood and CNS. Laboratory diagnosis involves gram stain, culture on selective media, and rapid carbohydrate utilization tests. Gonorrhea pathology in females includes salpingitis, tubo-ovarian abscess,

1. INFECTIOUS DISEASE OF
PATHOLOGY
(Bacterial Diseases)
Niesseria
Dr. Naila Awal

2. Classification
Neisseria
Pathogenic
• N. gonorrhea
• N. meningitidis
Non- Pathogenic
N. flava
N. subflava
N. pharyngitidis

3. Virulent factor
1) Pili- attach with host cell & anti phagocytic.
2)LPS- causes endotoxic shock
3)Ig A protease- Degrade Ig A coating -->
invade mucus.
4) Capsule- Adhesion & antiphagocytic.

4. Pathogenesis of Neisseria
gonorrhoeae
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Agent- Neisseria gonorrhoeae
Host- Human
Reservoir- Patient suffering from gonorrhea
Source of infection- Urethral/ Endocervical discharge
Mode of transmission-
a) Sexual contact
b) Vertical transmission-Mother to fetus through the birth
canal (Opthalmia neonatorum)
Incubation period- 2-10 days

5. Primary infection begins at the columnar epithelium of
urethra & peri urethral gland. Also in endocervix, rectal
mucosa & conjunctiva.
After contact, bacteria attach to epithelial cell by pili
Then pass between the epithelial cell & goes to submucosa
& multiply
Immune response, manifested by inflammatory exudates
which is at 1st serous & later on purulent together with
infiltration of huge number of neutrophil & pus cell.
From primary site they spread upward to involve the other
sides of the body & causes lesion

6. Primary lesion
• Male- Acute anterior urethritis
Proctitis
Pharyngitis
• Female- Acute anterior urethritis
Endocervicitis
Note- They do not cause vaginitis, B/cA) vagina contain stratified squamous epithelium which prevents
attachment of N. gonorrhea.
B) Vaginal pH- acidic (Lactobacillus)
• Children- Vulvo vaginitis
• New born- Opthalmia neonatorum.

7. Secondary lesion
1)Via direct spreadMale
Prostatitis
Epididymitis
Female
Oophoritis
Salphingitis
Endometritis
Tubo- ovarian abscess
Bartholinitis
Pelvic peritonitis

8. 2)Via lymphaticsCystitis
Pyelonephritis
Pyelitis
3) Via hematogenous route•
•
•
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Ulcerative endocarditis
Septic arthritis
Tenosynovitis
Iritis

9. Pathogenesis of N meningitidis
• Mode of transmission- By airborne droplet
N meningitidis
Enter into nasopharynx & attach to epithelial cell of nasopharynx.
Invade mucous membrane
Colonize
Enters to the blood stream
CNS
Through pili, they attach to the meninges--> Meningitis

10. Complication
Male
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Chronic prostatitis
Vesiculitis
Urethral stricture
Sterility –Due to fibrosis
caused by
bilateral epididymitis
Female
Sterility
Abortion-due to Endometritis
PID
Ectopic pregnancy( Due to
fibrosis of FT)

11. Lab diagnosis
SampleAcute infection• Male-Urethral discharge
• Female-Endocervical discharge
Chronic case• Male-Prostatic discharge by prostatic massage.
• Female-Endocervical discharge
Note- Not High vaginal swab b/c vaginal wall usualy not infected by
N. gonorrhoeae b/c it is lined by stratified squamous epithelium .

12. 3) In case of proctitis- Rectal swab
4) In case of arthritis- Joint fluid
5) In case of opthalmia neonatorum –conjunctival
discharge.
Lab procedure1) Gram staining- Gram negative Intracellular &
extracellular diplococci
plenty of pus cell
& neutrophil.

13. 2)CultureNon- specificChocolate agar- Heat lysed sheep blood+ Agar
Specific culture mediaA) Modified New York City media (MNYCM)
Heat lysed sheep blood+ Agar+ Antibiotic (Lincomycin,
Colistin, Nystatin, Trimethoprim)
B) Thayer Martin Media (TMM)
Heat lysed sheep blood+ Agar+ Antibiotic (Vancomycin,
Colistin, Nystatin, Trimethoprim)

14. • NoteWhich 1 is better, MNYCM/TMM?
MNYCM b/c1) Contain Lincomycin
2)10% of Niesseria are sensitive to Vancomycin.
( Vancomycin kill Niesseria)
So we will miss 10% case if we use TMM.
But all gonococci are resistant to Lincomycin.

15. Incubate at 37C for 18-24 hrs in microaerophilic
environment by candle jar.
• Observation- 0.5-1 mm, circular, convex, graiysh white
translucent colony.
4) Gram staining- Gram negative diplococci
5) Biochemical test• Oxidase test- Positive test
• Rapid carbohydrate utilization test (RCUT)• N. Gonorrhoeae ferment glucose but not maltose.
• N. meningitidis ferment both.
6) Detection of Ag/Ab- Can be detected in serum but it is
useless as N. Gonorrhoeae undergoes rapid antigenic
mutation.

16. Pathology of gonorrhoea in
female genital tract
Acute Suppurative salphingitis- Tubal mucosa -->
congested
Infiltration of neutrophil, plasma cell & lymphocytes.
Salphingo-oophoritisTubal lumen is filled with exudates--> leak out of fimbriated
end--> Spill over to ovary.
Tubo-ovarian abscess- Collection of pus within tube &
ovary.
Pyosalphinx-Collection of pus within tube.
Chronic follicular salphingitis- The tubal epithelium is
denuded--> adhere to 1 another -->fuse to form gland
like space / pouch

17. Pathology of gonorrhea in
male genital tract
Extension of infection• Posterior urethra-->prostate-->Seminal vesicle->Epididymis
• Epididymis--> Frank abscess-->Extensive
destruction of the organ.
In neglected cases, the infection may spread to
testis & produce suppurative orchitis.