Development of the accelerated phase during ascorbic acid therapy in Chediak-Higashi syndrome and efficacy of colchicine on its management.

Clinical studies were done on a patient with Chediak-Higashi syndrome (CHS) with special emphasis on the accelerated phase. In order to obtain further information on the accelerated phase, haematopoiesis was studied by bone marrow culture techniques. The patient was placed on ascorbic acid therapy but she entered the accelerated phase, although the therapy improved in vitro neutrophil function to some extent. Administration of microtubulytic drugs such as vincristine, vinblastine and colchicine was effective in the management of the accelerated phase. Numbers of macrophage-granulocytic (CFU-C) and erythroid (CFU-E) progenitor cells were markedly decreased or absent during the accelerated phase, being another indicator of the accelerated phase.