Neisseria

Question 1

Diagnosis of Neisseria Meningitidis

Answer 1

Gram (-) diplococci, oxidase (+), areobic
test:
1) CSF gram stain–> CSF high cell count w/ PNFs,
low glucose, high protein
2) PCR –> CSF and blood
3) Gram stain
4) Latex agglutination for capsular polysaccharides

Question 2

Transmission of Neisseria Meningitidis

Answer 2

Through repiratory secretions
–> colonizes the Nasopharynx - Adheres upper respiratory mucosa, forms microcolonies and biofelm (Biofelm is an entery portal for invasion)

Question 3

VF of Neisseria Meningitidis

Answer 3

Capsulated- Polysaccharide capsule
(Uncapsulated strains rarely cause disease)
–> 6 serogroups (A,B,C,W-135, X,Y)

Question 4

clinical Manifestations of Neisseria Meningitidis

Answer 4

1) Meningitis
2) Meningococcemia
3) waterhouse-friderichsen syndrome: adrenal
haemorrhage w/ necrosis
–> disseminated intravascular coagulation: gangrene,
digit & limb loss septic shock & death (due to high LPS)

Question 5

Treatment of Neisseria Meningitidis

Answer 5

1) Abx –> IM ceftriaxone or Benzyl penicillin

• Start Tx ASAP to reduce risk of death (as bacterial doubling time is 30 min- window of oprotunitiy closes quickly)

Question 6

Prophylaxis and Chemoprophylaxis of Neisseria Meningitidis

Answer 6

Prophylaxes:
-eliminate meningococci from close contacts,
chemotherapy to prevent disease in exposed

Chemoprophylaxis:
-rifampicin 2d (not for pregnant)
- ceftriaxone single dose IM (pregnant ok)
-ciprofloxacin single dose (not pregnant or
children)
-azithromycin single dose

Question 7

Clinical Signs of Meningitis casued by N.Meningitidis

Answer 7

Classic Triad : FEVER + NECK STIFFNESS + ALTERED MENTAL STATUS

other signs: rash (not as sever as in meningococcaemia)

Question 8

Clinical signs Test for meningitis caused by N.Meningitidis

Answer 8

Neck stiffness- Kernig’s sign- Burdzinski sign

Question 9

What clinical sign do you observe? What causative agent causes this ?

Answer 9

Petechial or Purpuric rash caused by Meningococcemia
CA; Neisseria Meningitides

Question 10

Clinical signs of Meningococcaemia caused by N.Meningitidis

Answer 10

Classic SIGN: petechial or purpuric rash

other signs:high fever, myalgia, hypotension, skin pallor, cold extermities

Question 11

Diagnosis of Neisseria Gonorrhoea

Answer 11

Diplococci, oxidase (+), aerobic

Tests:
1) Gram stain: Gram (-) diplococci in PNF (Specific for urethral exudates in males)
2) NAAT –> urine/ urethral swab (for men), Endocervical or vaginal (for women)
3) Culture –> swabs the same as NAAT, **DO NOT LET SPECIMEN DRY **

Question 12

Transmission of N.Gonorrhoea

Answer 12

STD
1) Oral, vaginal or anal

-often asymptomatic carriage

Question 13

Clinical manifestations of N.Gonorrhoea

Answer 13

Men : (2-5 incubation)
1) Acute urethritis
2) Purulent urethral discharge (PNFs, gonococci, dead epi cells)
3) Acute Epididymitis
4) Prostatitis
5) Dysuria
6) Urinary urgency

Women:
1) Upper genital tract infection- ascending from Cervicitis
2) Pelvic inflammatory disease—> Infertility, pelvic or abdominal pains = ascedning infection
4) disseminated gonococcal infection (DGI) –> Septic arthritis or polyarthritis

others:
1) Pharyngitis –> oral sex
2) Rectal infection
3) Neonants: Gonococcal infection