Disseminated Mycobacterium kansasii infection associated with hemophagocytic syndrome

Disseminated infections with hemophagocytic syndrome caused by non-tuberculous mycobacteria (NTM) are rare. A 60-year-old woman, who presented with fever, chills, anorexia, and right upper quadrant pain, was admitted to our hospital. Hepatosplenomegaly, pancytopenia, elevated liver aminotransferases, and hyperferritinemia were noted after admission. A gallium scan and chest computed tomography revealed multiple mediastinal lymphadenopathy. A bone marrow examination revealed hemophagocytosis. Bone marrow and liver biopsies showed non-caseating granulomatosis and cultures from bone marrow and liver all yielded Mycobacterium kansasii. The patient responded well to azithromycin, isoniazid, rifampin, and ethambutol. No immunocompromised conditions such as malignancy, autoimmune disease, or HIV infection were detected initially. However, a right femoral tumor with pathological fracture was found five months later during follow-up at the outpatient clinic. Bone biopsy showed granulocytic sarcoma. To our knowledge, this is the first reported case of life-threatening hemophagocytosis due to M. kansasii. Patients with disseminated NTM infections should be closely monitored if any immunocompromising condition develops.