Impaired Growth During Interferon-α Therapy in a Patient with Chronic Myelogenous Leukemia

Abstract

An eleven-year-old boy with chronic myelogenous leukemia (CML) was treated by recombinant interferon-α (IFN-α) 6 × 10⁶ units per day intramuscularly for 6 months. Hydroxyurea (1000-500 mg per day) was added for one month during the 5th month of IFN-α therapy. Then a bone marrow transplantation (BMT) from his HLA matched sister was performed. His height gain during the 6 months on IFN-α was completely suppressed. His height increased 1.9 cm in the first year after BMT and then his height velocity accelerated with pubertal development. GH secretion was low at the end of IFN-α therapy when the pubertal growth spurt had not yet started. GH secretion examined 2 years after BMT when the patient was in puberty was almost normal. Complete suppression of height increase during IFN-α therapy in the patient might indicate that IFN-α directly affects the epiphysial growth plate rather than inhibition through the hypothalamic-pituitary axis. Growth impairment seems to be a serious side effect of long term and high dosage IFN-α therapy.