Neisseria, Haemophilus, Anaerobes

Question 1

What are the characteristics of Neisseria?

Answer 1

• gram - cocci
• N. meningitidis -> upper respiratory tract
• N. gonorrhoeae -> GU tract
• grows on thayer-martin agar
• oxidase & catalase +

Question 2

What are the virulence factors of n. gonorrhoeae?

Answer 2

• opa protein
• rmp protein
• LPS
• porins
• pilli

Question 3

What is the antigenic variation of n. gonorrhoeae?

Answer 3

• type 4 pilli
• about 100 stereotypes conserved at the N- terminal, highly variable at C-terminal; splicing PiLS genes with control region PiLE

Question 4

How are men & women affected by n. gonorrhoeae?

Answer 4

• men -> symptomatic
• women -> asymptomatic
• can infect eyes in infants & adults
• pelvic inflammatory disease can develop in women

Question 5

What is the immune response to n. gonorrhoeae?

Answer 5

• very little immunological memory is produced
• low levels of IgG & IgA produced
• immune response is local

Question 6

What is the diagnosis & treatment of n. gonorrhoeae?

Answer 6

• diagnosis: gram stain & oxidase +
• treatment: 3rd generation cephalosporins with azithromycin or doxycyclines

Question 7

What are the virulence factors & diseases of n. meningitidis?

Answer 7

• virulence: capsule -> systemic spread
• disease: meningitis

Question 8

What are the characteristics of haemophilus influenzae?

Answer 8

• gram - coccobacilli
• encapsulated strains -> invasive & cause epiglottis in unvaccinated children
• unencapsulated strains -> less invasive & colonize upper respiratory tract

Question 9

What are the virulence factors of haemophilus influenzae?

Answer 9

• capsule
• endotoxin
• IgA protease
• pili for adhesion

Question 10

What is epiglottis and its treatment?

Answer 10

• cherry red, swollen epiglottis protrudes into the airway
• treatment: rifampin

Question 11

What are the 4 species of anaerobic bacteria?

Answer 11

• clostridium perfringens
• clostridium tetani
• clostridium botulinum
• clostridium difficile

Question 12

What are the characteristics of clostridia species?

Answer 12

• gram + bacilli
• spore-forming

Question 13

What are the toxins of clostridium perfringens?

Answer 13

• alpha
• beta
• epsilon
• iota

Question 14

What ate the diseases associated with clostridium perfringens?

Answer 14

• skin infections: cellulitis & fascitis treated with hyperbaric oxygen
• food poisoning with meats

Question 15

What are the 2 toxins of clostridium tetani?

Answer 15

• tetanospasmin: irreversible binding & leads to spastic paralysis
• tetanolysin

Question 16

What is tetanus disease?

Answer 16

• generalized tetanus -> drooling, sweating, sustained contraction of masseter & facial muscles
• neonatal tetanus -> infection of umbilical stump
• localized tetanus

Question 17

What is the treatment of clostridium tetani?

Answer 17

toxoid vaccine & passive immunization

Question 18

How is flaccid paralysis caused in clostridium botulinum?

Answer 18

A-B toxin prevents the release of ACh

Question 19

What is botulism?

Answer 19

• fooborne -> bilateral descending flaccid paralysis & associated with home canning of foods
• infant -> associated with honey

Question 20

What are the characteristics of clostridium difficile?

Answer 20

• associated with antibiotics or hospital acquired infection
• presents as life-threatening pseudomembranous colitis
• enterotoxin -> chemotactic for neutrophils
• cytotoxin -> destroys cellular cytoskeleton

Question 21

What mutant is apart of clostridium difficile?

Answer 21

NAP1 associated with healthcare facilities

Question 22

What is the treatment for clostridium difficile?

Answer 22

• D/c antibiotics
• vancomycin or metronidazole for severe version
• fecal transplant

Question 23

What does neisseria gonorrhoeae cause?

Answer 23

• genitourinary infection -> sexually transmitted
• urethritis, cervicitis, sapingitis, pelvic inflammatory disease (PID)