Hemophilus Endocarditis: New Cases, Literature Review, and Recommendations for Management

Rarely is endocarditis attributed to the species of Hemophilus. Most frequently implicated are H aphrophilus and H parainfluenzae, but H influenzae also is seen. We report six cases of endocarditis due to H aphrophilus or H parainfluenzae and review the literature. Emboli to skin, lungs, kidneys, spleen, brain, and other organs are common complications, and acute glomerulonephritis and meningitis often occur. Ampicillin is the mainstay of antimicrobial therapy for patients whose isolates are sensitive to it, but the duration of antimicrobial therapy necessary for eradication of the infection is not clear. Studies of antimicrobial synergism are warranted in instances of endocarditis caused by ampicillin- or penicillin-resistant strains of Hemophilus, or when patients are allergic to penicillin; in these instances, combination antimicrobial therapy must be given when bactericidal synergism can be demonstrated. Intensive management of complications caused by embolization is crucial to patient survival.