GRAM NEGATIVE (-) DIPLOCOCCI (Neisseria and Moraxella catarrhalis)

Question 1

Gram-negative, coffee-bean shaped diplococci with adjacent sides flattened

Answer 1

Neisseria

Question 2

Transmission of N. gonorrhoeae:

Answer 2

• Sexual contact
• Infected mother to newborn during delivery

Question 3

N. gonorrhoeae infects _______ in males and ________ in females

Answer 3

Males: purulent urethritis
Females: primarily cervicitis

Question 4

Gonococcal infection of the eyes of infants:

Answer 4

Gonococcal opthalma neonatorum

Question 5

Neisseria specie that colonizes nasopharynx of healthy people:

Answer 5

Neisseria meningitidis

Question 6

Neisseria meningitidis is transmitted by:

Answer 6

Respiratory droplets

Question 7

Severe disease caused by N. meningitidis (bacteria entered the blood stream)

Answer 7

Fulminant meningococcemia

Question 8

DIC and circulatory collapse (Adrenal necrosis) caused by N. meningitidis:

Answer 8

Waterhouse-Friedrichsen syndrome

Question 9

Patients that are prone to recurrent Neisseria meningitidis infection are deficient in:

Answer 9

C5-C9 (part of membrane attack complex)

Question 10

Culture media incubation requirements for Gonococci and Meningococci:

Answer 10

incubate cultures in 5-10% CO2 (Capnophilic) and 50-70% humidity

Question 11

Tests that differentiates Neisseria and Moraxella catarrhalis

Answer 11

DNase test
- M. catarrhalis (+)
- Neisseria (-)

H2S (Superoxol test)
- M. catarrhalis (-)
- N. meningitidis (-)
- N. gonorrohoeae (+)

Question 11

Culture agar that encourages growth of both Haemophilus and Neisseria

Answer 11

Chocolate agar

Question 12

Differentiates Neisseria species:

Answer 12

CTA (cystine trypticase agar)

Question 13

For identification of N. gonorrhoeae in genitourinary specimens (preferred tests for these specimens); Excellent specificity and sensitivity in symptomatic, high-prevalence populations; PCR based; preferred test

Answer 13

NAAT (Nucleic Acid Amplification Tests)

Question 14

Member of the normal microbiota in 40% to 50% of healthy school children

Answer 14

Moraxella catarrhalis

Question 15

M. catarrhalis produces _______, which forms the basis for rapid fluorometric tests for identification:

Answer 15

Butyrate esterase

Question 16

Diseases caused by M. catarrhalis:

Answer 16

• Bronchitis
• pneumonia
• sinusitis
• otitis media
• conjunctivitis
• Also of concern as a cause of infection in immunocompromised patients