Mineral homeostasis and diagnosis in children with lymphoblastic leukemia bone mass at acute Jacqueline M. Halten, MD, Stephanie A. Atkinson, PhD, Laurence Fraher, PhD, Colin E. Webber, PhD, W. Peter Cockshott, MB,ChB, MD,t Cherk Tam, MD, and Ronald D. Barr, MB,ChB, MD From the Departments of Pediatrics, Radioiogy, and Nuclear Medicine, McMaster University, Hamilton, Ontario; Research Institute, St. Joseph's Hospital, University of Western Ontario, Lon- don; and Queen Elizabeth Hospital, University of Toronto, Toronto, Ontario, Canada Objective: To determine whether the osteopenia and unusual fractures ob- served in children with acute lymphoblastic leukemia (ALL) were related to the disease rather than to its treatment. Design: Prospective analysis of the bone and mineral status in 40 consecutive children with ALL seen in a pediatric tertiary-care referral center. Methods: Biochemical indicators of mineral, endocrine, and vitamin D status were measured before initiation of therapy. Bone mass was determined radio- graphically and by dual-photon absorptiometry of the lumbar region of the spine (L2-L4). Correlations between clinical observations, leukemia variables, bone mass, and biochemical assessment were determined. Results: At the time of diagnosis musculoskeletal pain was present in 36% of pa- tients and was more common in children with CD10-positive leukemia and leu- kocyte counts less than 20 × 109 cells/L. Radiographic evidence of osteopenia and fractures was observed in 13% and 10% of children, respectively. The mean bone mineral content was normal. Bone mass measurement zscores correlated with plasma 1,25-dihydraxyvitamin D3 concentrations (r = 0.43, p <0.05). Plasma calcium, magnesium, phosphorus, and 25-hydroxyvitamin Da levels were nor- mal. Low plasma osteocalcin (mean ± SD, 1.6 ± 1.6 nmol/L) and 1,25-dihydrox- yvitamin D3 (33.4 __+ 26.4 pmol/L) values were observed. Parathyroid hormone levels were Iow in 14% of children. Hypercalciuria was detected in 64% of chil- dren. Urinary deoxypyridinoline was Iower (p <0.01) than in age-matched con- trol subjects. Histomorphometric measurements of iliac bone showed abnor- malities in mineralization in the biopsy specimens from three of nine children. Conclusion: Most children with ALL have alterations in bone metabolism and bone mass when first examined. These data suggest defective mineraiization as the mechanism for decreased bone mass and implicate the leukemic process as causative. (J PEDIATR 1995;126:557-64) Supported by a grant from the Hospital for Sick Children Foun- dation, Toronto, Ontario, Canada. Dr. Halton held a Fellowship from the National Institute of Nutrition (Canada). Dr. Atkinson received a Career Scientist Award at McMaster University from the Ontario Ministry of Health. Dr. Fraher received a University Scholar's Award from the National Institute of Nutrition (Cana- da). Submitted for publication Jan. 10, 1994; accepted Nov. 28, 1994. Reprint requests: Stephanie Atkinson, PhD, Department of Pedi- atrics, McMaster University, 1200 Main St. West, Roorn 3V42, Hamilton, Ontario, Canada LSN 3Z5. tDeceased. Copyright ® 1995 by Mosby-Year Book, Inc. 0022-3476/95/$3.00 + 0 9/20/62346 557