Chapter 17: Neisseria and Moraxella

Question 1

What are the general characteristics of the Neisseriaceae family?

Answer 1

Aerobic, capnophilic, gram-negative diplococci. Oxidase- and catalase-positive.

Exceptions include N. elongata and N. bacilliformis (catalase-negative) and N. weaver (catalase-positive, rod-shaped).

Question 2

Where do Neisseria species commonly exist in the human body?

Answer 2

Upper respiratory and urogenital tracts as usual microbiota.

Most isolates are not pathogenic.

Question 3

What are the primary pathogenic species of Neisseria?

Answer 3

• N. gonorrhoeae
• N. meningitidis

Question 4

What are some virulence factors of Neisseria?

Answer 4

• Receptors for human transferrin
• Capsule (N. meningitidis)
• Pili (fimbrae)
• Cell membrane proteins
• Lipooligosaccharide (LOS)
• Immunoglobulin A (IgA) protease

Question 5

What is the only natural host for N. gonorrhoeae?

Answer 5

Humans

Question 6

What is another name for gonorrhea derived from French?

Answer 6

Clap

Question 7

What is the incubation period for N. gonorrhoeae in men?

Answer 7

2 to 7 days

Question 8

What are common symptoms of gonorrhea in men?

Answer 8

• Dysuria
• Urethral discharge

Question 9

What complications can arise from N. gonorrhoeae infections in men?

Answer 9

• Epididymitis
• Urethral stricture
• Prostatitis

Question 10

What is the most common site of infection for N. gonorrhoeae in women?

Answer 10

Endocervix

Question 11

What are possible complications of N. gonorrhoeae infections in women?

Answer 11

• Pelvic inflammatory disease (PID)
• Sterility
• Ectopic pregnancy
• Perihepatitis (Fitz-Hugh-Curtis syndrome)

Question 12

What is a less common manifestation of N. gonorrhoeae infection?

Answer 12

Disseminated gonococcal disease (less than 1%)

Question 13

What is the recommended method for specimen collection for N. gonorrhoeae?

Answer 13

Urethra in males: collect purulent discharge or insert swab if no discharge.

Question 14

What type of media is used for transporting specimens for N. gonorrhoeae?

Answer 14

• Transgrow
• JEMBEC
• Bio-Bag
• Gono-Pak
• Amies medium

Question 15

What is the Gram stain morphology of N. gonorrhoeae?

Answer 15

Gram-negative, kidney bean–shaped diplococci

Question 16

What is the incubation condition for N. gonorrhoeae culture?

Answer 16

35°C in 3% to 5% carbon dioxide (CO2)

Question 17

What is the purpose of the oxidase test in laboratory diagnosis of N. gonorrhoeae?

Answer 17

To identify the presence of cytochrome c oxidase.

Question 18

What are the common clinical manifestations of N. meningitidis?

Answer 18

• Frontal headache
• Stiff neck
• Nausea and vomiting
• Fever

Question 19

What is a serious complication of meningococcemia?

Answer 19

Waterhouse-Friderichsen syndrome

Question 20

What is the treatment for confirmed meningitis caused by N. meningitidis?

Answer 20

Penicillin

Question 21

What is the role of M. catarrhalis in human health?

Answer 21

Normal commensal of the respiratory tract and important opportunistic pathogen.

Question 22

What are common clinical infections caused by M. catarrhalis?

Answer 22

• Pneumonia
• Sinusitis
• Otitis media

Question 23

What are the identification characteristics of M. catarrhalis?

Answer 23

• Oxidase positive
• Catalase positive
• Asaccharolytic

Question 24

What are the recommended antibiotics for treating N. gonorrhoeae infections?

Answer 24

• Ceftriaxone
• Oral Azithromycin or doxycycline for C. trachomatis

Question 25

Fill in the blank: N. meningitidis strains are primarily encapsulated strains A, B, C, Y, and _____

Answer 25

W-135

Question 26

True or False: N. gonorrhoeae can cause infections in the anal canal.

Answer 26

True

Question 27

What is the common age group affected by N. meningitidis?

Answer 27

Infants, adolescents, and immunocompromised individuals.

Question 28

What can neutropenia lead to?

Answer 28

Severe infections ## Footnote Neutropenia is a condition characterized by an abnormally low number of neutrophils, increasing susceptibility to infections.

Question 29

What are the primary methods for specimen collection and identification?

Answer 29

Middle ear effusion, nasopharynx, sinus aspirates, sputum, bronchial aspirates ## Footnote These methods are used to collect samples for microbiological analysis.

Question 30

What are the characteristics of M. catarrhalis?

Answer 30

Oxidase and catalase positive, asaccharolytic, positive DNase and butyrate esterase reactions ## Footnote These characteristics help in the identification of Moraxella catarrhalis in laboratory settings.

Question 31

What are the three groups of Neisseria species?

Answer 31

Group 1: pathogens, Group 2: commensals that grow on selective media, Group 3: commensals that do not grow on selective media ## Footnote This classification helps in understanding the pathogenic potential of different Neisseria species.

Question 32

List some nonpathogenic Neisseria species.

Answer 32

* N. cinerea * N. flavescens * N. lactamica * N. mucosa * N. polysaccharea * N. sicca * N. subflava * N. elongata * N. weaveri ## Footnote These species are typically part of the normal flora and rarely cause disease.

Question 33

What is the colonial morphology of most Neisseria spp.?

Answer 33

Gram-negative diplococci that occur in pairs with adjacent sides flattened ## Footnote This morphology is a key characteristic used for identification in laboratory settings.

Question 34

What environmental conditions do Neisseria species prefer for growth?

Answer 34

Increased CO2 and humidity ## Footnote These conditions mimic the human body environment, facilitating optimal growth of Neisseria species.

Question 35

Which Neisseria species are considered primary human pathogens?

Answer 35

N. gonorrhoeae and N. meningitidis ## Footnote These species are well-known for causing significant diseases in humans.

Question 36

What is the incidence of infections caused by commensal Neisseria spp.?

Answer 36

Very low ## Footnote This indicates that while these species are present in the human microbiome, they rarely lead to infections.

Question 37

What opportunistic infections is Moraxella catarrhalis associated with?

Answer 37

Otitis media, sinusitis, lower respiratory infections ## Footnote Moraxella catarrhalis is a common commensal organism in the upper respiratory tract.