No abstract

Severe symptomatic hypercalcemia is a rare event in children with malignancies. Up to now there is limited experience treating childhood hypercalcemia with bisphosphonates in addition to calcitonin. We report a 5-year-old boy with acute lymphoblastic lymphoma who presented with malignant hypercalcemia at diagnosis. The maximal serum calcium concentration was 15.2 mg/dl (3.81 mmol/l). Conventional therapy with forced diuresis and furosemide failed. Calcitonin (10 IU/kg/24 h i.v. for 2 days) and pamidronate (1 mg/kg over 2 hours i.v.) were used successfully without adverse effect lowering the serum calcium level within 24 hours to normal values. We recommend the use of calcitonin and pamidronate as first-line therapy together with forced diuresis and furosemide in childhood hypercalcemia secondary to malignancies as it is rapidly effective and has no significant side effects.

Azathioprine and its active metabolite 6-mercaptopurine are of increasing importance in the treatment of chronic inflammatory bowel disease. Most of the toxicity and the side effects of the medications are well known. However, it is relatively unknown that azathioprine toxicity itself can produce devastating diarrhea in patients with inflammatory bowel disease. This leads to great difficulties in differential diagnosis. We describe 2 patients with severe intestinal toxicity. This was life-threatening in 1 patient after reintroducing the drug. We therefore believe that any rechallenge with azathioprine should be only undertaken in a controlled hospital environment when a reaction to azathioprine is suspected. In addition, we found that this devastating intestinal toxicity did not reoccur after rechallenge with its active metabolite 6-mercaptopurine. Azathioprine and 6-mercaptopurine therefore cannot be used interchangeably.