Transient Haemophilus influenzae type b bacteremia in a healthy child

Occult bacteremia with Streptococcus pneumoniae (S. pneumoniae) is sometimes experienced in general clinics, while that with Haemophilus influenzae type b (Hib) is less common and mostly develops to serious central nervous infection. Recently we encountered a patient with bacteremia due to Hib, in whom bacteremia recovered spontaneously without intravenous antibiotic therapy. A previously healthy 17-month-old girl was brought to our hospital with the complaint of high fever. Although her clinical condition did not present any of meningeal signs, the laboratory data on the first day showed prominent leukocytosis and sepsis work-up was done. Two days later (third day of illness), blood culture grew Haemophilus influenzae sensitive to ampicillin and the strain isolated from blood was identified as Hib. The febrile condition soon disappeared and bacteremia resolved with the negative result of the next blood culture. It is not clear about the precise mechanisms of this phenomenon, however, it is an extremely rare case for Hib bacteremia to resolve spontaneously.