Progressive Langerhans cell histiocytosis in an infant with Klinefelter syndrome successfully treated with allogeneic bone marrow transplantation

Purpose: We describe successful treatment of an infant with progressive Langerhans cell histiocytosis (LCH) with allogeneic bone marrow transplantation (BMT), and discuss a chromosomal abnormality discovered in his LCH-affected tissue. Patients and Methods: A 4-month-old male infant with a seborrheic-appearing rash, respiratory collapse, and spontaneous pneumothorax is presented. LCH was diagnosed with primary involvement of skin and lungs. His disease progressed despite aggressive multiagent chemotherapy that included high-dose methylprednisolone, vinblastine, cyclophosphamide, methotrexate, 2-chlorodeoxyadenosine, and etoposide. Results: The patient was successfully treated with myeloablative therapy and low-dose total body irradiation followed by allogeneic BMT at the age of 16 months, at which time he had multisystem involvement. One hundred percent 47XXY/14p+ cells were identified from a lung biopsy; peripheral blood chromosomal analysis demonstrated mosaic 47XXY/14p+, and normal 46XY. Conclusions: Allogeneic BMT may be used successfully in the treatment of refractory, progressive LCH in infants, who are at highest risk of mortality. The cytogenetic association between Klinefelter syndrome and LCH has not been described previously. Cytogenetic analysis of other patients with LCH may be beneficial in determining a genetic association between LCH and Klinefelter syndrome and/or abnormalities of chromosome 14.