A 14-year-old girl of Indian origin with acute myeloid leukemia (AML) is presented, who was diagnosed at the age of twelve. Antileukemic chemotherapy had to be discontinued after 6 weeks because of persistent high fever and the emergence of liver and spleen abscesses. Serologic and biopsy findings were consistent with disseminated candidiasis; however, a liver biopsy also revealed granulomatous lesions with caseous degeneration. No acid-fast bacilli could be detected. Upon antifungal treatment the patient's condition improved, but fever spells and high inflammatory blood parameters persisted. One year after the diagnosis of AML was established, Mycobacterium avium was cultured from bone marrow aspirates. The patient's cellular immunity was severely compromised at that time as reflected by the marked depression of T-lymphocyte counts, in particular of CD4-positive cells. HIV and other lymphotropic virus infections were subsequently excluded. After 5 months of specific treatment the patient recovered from mycobacterial infection and remains in first remission of AML. Opportunistic infections have rarely been diagnosed in oncologic patients to date, while data on T-cell function in AML is sparse. Fever of unknown origin should prompt the search for infectious agents unusual to date in this patient group.
