SAN DIEGO — The most aggressive variant of Langerhans cell histiocytosis, Letterer-Siwe disease is characterized by cutaneous involvement, organo-megaly, and thrombocytopenia, Joseph P. Janik, M.D., said during a poster session at the annual meeting of the Society for Pediatric Dermatology.
The patient was thrombocytopenic and had an enlarged spleen and liver, but there were no lung abnormalities. The results of two shave biopsies confirmed the diagnosis, said Dr. Janik, the lead author of the case report, of the department of dermatology at the University of New Mexico, Albuquerque.
Few controlled studies exist for the treatment of the Letterer-Siwe variant of Langerhans cell histiocytosis, let alone the congenital form. PUVA and topical nitrogen mustard seem to be most effective for the skin lesions while vinblastine or etoposide have been used for the systemic manifestations (J. Pediatr. 1991; 119:317–21). For nonresponders, a combination chemotherapy can be tried.
The response rate to monochemotherapy can reach 90%, but the overall outcome is usually fatal, especially in the congenital form of Letterer-Siwe (Cancer 1988;62:2528–31). At press time, this patient is alive at the age of 21 months, after a year of treatment with vinblastine, prednisone, and 6-mercaptopurine.
Dr. Janik discussed another case of the Letterer-Siwe variant of congenital Langerhans cell histiocytosis in a baby born at 28 weeks' gestation. Apgar scores for the baby, who was delivered via emergent C-section, were 2 at 1 minute, 1 at 5 minutes, and 1 at 10 minutes. Resuscitation attempts were unsuccessful, and the baby expired 25 minutes after birth.
Ran H. Bang, M.D., Charles H. Palmer, M.D., E. Ben Smith, M.D., and R. Steven Padilla, M.D., all of University of New Mexico, assisted with the case reports.