Haemophilus Flashcards
what is the biology of heamophilus?
Pleomorphic GNB *
what are the Medically imp. species of haemophilus?
- Haemophilus influenzae *
- H. ducreyi
- H. aegypticus
apart from pleomorphic, haemophilus can as well be identified other times in what shape?
coccobacilli
fastidious haemophilus influenzae has 2 important factors?
Hemin (factor X) and NAD (factor V) *
what agar is used to identify haemophilus influenzae?
chocolate blood agar
where is haemophilus influenzae found normally in the body?
nasopharynx
what strains of haemphilus are more virulent?
encapsulated strains
how does haemophilus influenzae spread?
respiratory droplets
what is the 2nd encapsulated strain of haemophilus influenzae?
Type b
what is the type B capsule made of?
polyribitol phosphate (PRP) *
what test used to diagnose type B haemophilus influenzae?
CSF antigen screens *
haemophilus influenza capsule is used for what purpose medically?
vaccination
does H. influenzae have IgA protease *? what does it do?
yes; Degrades secretory IgA facilitating colonization of upper respiratory mucosa
Colonization of upper respiratory mucosa may lead to continous spread causing what?
- Sinusitis, otitis media
- Epiglottitis
- Bronchopneumonia
if h. influenzae becomes bacterimic, it will lead to what?
- Meningitis
- Septic arthritis
what diseases does Haemophilus influenzae cause?
- Otitis media , Sinusitis *
- Bronchitis, Pneumonia * (NTHi)
- Meningitis *
- Epiglottitis * - Life-threatening emergency
- Cellulitis
- Septic arthritis
who is susceptible to meningitis due to h. influenzae?
unvaccinated children (3 months to 2 years)
what is a good way to confirm a meningitis diagnosis due to h. influenzae?
CSF gram stain * – showing gram negative coccobacilli
what is the treatment for meningitis due to h. influenzae?
Ceftriaxone
what is the treatment for sinusitis due to h. influenzae?
ampicillin
what is the treatment for otitis media due to h. influenzae?
ampicillin
what two other haemophilus species are there?
H. aegyptius *
H. ducreyi *
what does H. aegyptius * cause?
purulent conjunctivitis, “pink eye”
what does H. ducreyi * cause?
Genital ulcers – “Chancroid”, an STD *
- Soft, painful ulcer
- Open lesions increase transmission of HIV
H. ducreyi caused genital ulcers are treated with what?
erythromycin
how does H. ducreyi spread?
sexually transmitted
