Hypercalcemia and osteolytic lesions as presenting symptoms of acute lymphoblastic leukemia in childhood. The use of zoledronic acid and review of the literature.

Hypercalcemia is rare in children with etiology different from adults. We report an 11.5-year-old boy with developmental delay that presented with difficulty in walking and vomiting. Laboratory investigations revealed hypercalcemia (Ca 13.8 mg/dL) with low serum parathormone, normal full blood count and no circulating blasts. Osteolytic lesions were discovered on radiological survey. Bone marrow examination was consistent with the diagnosis of common B acute lymphoblastic leukemia (ALL). Hypercalcemia was successfully treated with zoledronic acid. Hypercalcemia is a rare but well-recognized complication of ALL, usually present at the time of initial diagnosis. We reviewed the literature and analyzed the clinical and laboratory data in 36 cases of childhood ALL presenting with hypercalcemia. In conclusion, hypercalcemia alone or combined with osteolytic lesions can be the only presenting symptom of ALL in children.