Acute lymphocytic leukaemia presenting as a metabolic bone disease.

A 7-year-old boy presented with the acute onset of low backache of 2 months duration. An x-ray of thoracolumbar spine revealed multiple vertebral fractures, and biochemical evaluation showed hypercalcaemia with a suppressed parathyroid hormone which raised the possibilities of malignancy, granulomatous conditions or vitamin D toxicity. Despite the absence of blast cells in his blood, the bone marrow biopsy was unequivocally diagnostic of acute lymphoblastic leukaemia.