RESUMEN
Haemophilus influenzae rarely causes acute endometritis and the few published cases have always been associated with intrauterine devices (IUD). A 48-year-old female presented to the emergency department with a 3-day history of lower abdominal pain and fever. On physical examination she was tachycardic, hypotensive and had fundic tenderness to palpation. Imaging showed uterine leiomyomas and no IUD. Blood cultures grew a non-typable H. influenzae. Endometrial biopsy demonstrated acute endometritis. Tissue Gram stains and cervico-vaginal cultures were negative; however, polymerase chain reaction (PCR) determined presence of H. influenzae on the formalin-fixed, paraffin-embedded tissue biopsy. Evidence of H. influenzae in the endometrium demonstrates that the uterus can be the nidus for sepsis when invasive H. influenzae is found with no distinct usual primary focus. This case underscores the importance pathologic diagnosis and molecular testing.