Bacteremia due to nontypable Haemophilus influenzae--three cases in a community hospital.

Nontypable Haemophilus influenzae is a normal inhabitant of the upper respiratory tract and a common pathogen in diseases limited to mucosal surfaces. Nontypable H. influenzae has only occasionally been reported to cause invasive disease locally or systemically. In a period of two years, three patients of 17 with positive blood cultures for H. influenzae were found to have nontypable strains, two of which were resistant to ampicillin. The presumed sites of entry were an oral mucosal lesion, sinus mucosa, and female genital tract. All three patients responded rapidly to antibiotics to which their isolates were susceptible.