- Small aerobic gram-negative coccobacillus found mainly in human respiratory tract.
- H. influenzae is the most notable species, but decline in past decades due to active childhood immunization (Hib).
- Encapsulated, type b strain accounts for most bacteremic pneumonia and invasive disease, whereas non-encapsulated strains mostly cause otitis media, sinusitis, AECB and pneumonia.
- Sensitivity of Gram stain and Cx probably ~50% in pts with H. influenzae pneumonia. Use of prior abx will decrease yield.
- Non-typeable H. influenzae strains more common now than type b. Other Haemophilus strains (H. aphrophilus, now called Aggretibacter aphrophilus) occasional cause of infection in HIV.
Haemophilus species was found in Johns Hopkins HIV Guide.
If you are a registered user, please log in below.
If not, learn more about gaining full access.
- Johns Hopkins Guides include up-to-date, authoritative content to help you treat patients and raise the standard of care.
Try these free topics now!
Johns Hopkins ABX Guide
Johns Hopkins Diabetes Guide
Johns Hopkins HIV Guide