We report a case of Macrophomina phaseolina skin infection in an immunocompromised child with acute myeloid leukemia, which was treated successfully with posaconazole without recurrence after a hematopoietic stem cell transplant. The fungus was identified by DNA sequencing using both the internal transcribed spacer and D1/D2 region of the 28S ribosomal DNA gene.
CASE REPORTA 6-year-old Caucasian girl was diagnosed with acute myeloid leukemia carrying the t(11;19) translocation. She underwent a matched, unrelated hematopoietic stem cell transplant (HSCT) because of increasing minimal residual disease but suffered a relapse in her bone marrow 5 years later. She was then reinduced with a 5-day course of clofarabine, etoposide, and cyclophosphamide. Following this course of chemotherapy, she was discharged from the hospital and placed on prophylactic voriconazole (VRZ), vancomycin, ciprofloxacin, and trimethoprim-sulfamethoxazole. Three weeks later, she presented as an outpatient with tenderness and erythema of a few days' duration above the right medial malleolus.She had no complaints of fever or leg pain and had sustained no trauma to the right leg. On examination. she was afebrile and looked well. Her temperature was 37.1°C, pulse was 101 beats/min, respiratory rate was 20/min, and blood pressure was 95/56 mm Hg. Her lungs were clear to auscultation, and examination of her abdomen revealed no tenderness or hepatosplenomegaly. She had a 2-by-2-cm erythematous, papular, nonulcerative, tender lesion above the right medial malleolus with no induration or inguinal lymphadenopathy. There were no other skin lesions. Her complete blood count revealed a white cell count of 0.1 cells/l (range, 1,800 to 8,000 cells/l), platelet count of 17,000/l (range, 170 to 450,000 cells/l), and hemoglobin of 9.1 g/dl (range, 12 to 16 g/dl). Blood cultures showed no growth. The lesion progressed over the next week on antibiotic and antifungal therapy with meropenem, vancomycin, and VRZ. It became indurated, with a central necrotic eschar and a surrounding rim of erythema, and extended into the subcutaneous tissue. She continued to appear well during this period. Magnetic resonance imaging of the right lower tibia and fibula revealed nonenhancing edema of the skin and subcutaneous fat involving the medial distal right lower leg without muscle or bone involvement or any drainable fluid collection. Computerized tomography of the chest and abdomen revealed no evidence suggestive of any fungal lesions.A punch biopsy was performed through the central ulcerative lesion. The histology showed focal epidermolysis and dermal necrosis accompanied by predominantly histiocytic infiltrate and microhemorrhages. Histopathologic examination with periodic acid-Schiff and Gomori methenamine silver stains revealed abundant infrequently branching septate hyphae in the epidermis and dermis, invading the blood vessels (Fig. 1). There was no pigment seen on the hyphal walls on hematoxylin-eosin or melan A staining.The biopsy specimen was sent for bacterial and f...
