Bone mineralization defects after treatment of acute lymphoblastic leukemia ın children

Aim of the study was to assess bone metabolism disturbances in children with acute lymphoblastic leukemia following cessation of chemotherapy. For this purpose we measured bone mineral density (BMD) and evaluated bone metabolism markers.

Seventy-five patients (37 female, 38 males, mean age 10.77±3.80 years) were included. Lumbar spine BMD was measured by dual energy X-ray absorptiometry and serum calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone and 25OH vitamin D levels were analyzed. For characteristics of all patients at diagnosis data were retreived from hospital records and analyzed retrospectively.

A total of 18.66% (14 patients) of patients were osteoporotic (z score <-2 SD), 22.67% (17 patients) were osteopenic (z-score between -2 and -1 SD) and 58.67% (44 patients) presented normal z-scores (>-1 SD). There were no statisticaly significant differences between normal, osteopenic and osteoporotic groups for mean serum vitamine D (P=0.677), calcium (P=0.280), phosphorus (P=0.179), magnesium (P=0.675), ALP (P=0.092) and serum PTH (P=0.915) levels. According to ages (P=0.745) and gender (P=0.810) there were no significant differences in BMD. There were no significant differences between normal, osteopenic and osteoporotic patients for the total dose of prednisolone (P=0.334), dexamethasone, (P=0.734), methotrexate (P=0.911), granulocyte colony-stimulating factor (P=0.173) and cranial irradiation (P=0.912) they have received during chemotherapy. Bone fracture and aseptic necrosis rates were 12%, 8%, respectively.

Osteoporosis and osteopenia are still observed in high rates after chemotherapy. We must be aware of this morbidity and must screen the patients for decreased BMD during the long duration of leukemia treatment. Supportive treatments should be evaluated to minimize these serious complications.