Diffuse calcinosis cutis in a patient with congenital leukemia and leukemia cutis

We report an unusual case of congenital leukemia with leukemia cutis (LC) and diffuse calcinosis cutis. A newborn girl presented with widespread dusky red and yellowish cutaneous nodules and papules. Bone marrow morphology was consistent with the diagnosis of acute monocytic leukemia of the FAB M5 type. Skin biopsy specimens confirmed the presence of a leukemic infiltrate and revealed calcium salt deposition in the papillary and reticular dermis. Calcinosis was diffuse in the whole skin but spared other organs. Vascular calcification was not present. Serum calcium levels oscillated between 2.5 and 2.86 mmol/l, and phosphorus, parathyroid hormone and 25-hydroxyvitamin D(3) levels were normal. There were diffuse osteoporosis and spontaneous fractures of small tubular bones. The patient responded to chemotherapy but, following consolidation treatment, developed sepsis and died at 120 days of age. Congenital leukemia is rare and LC is uncommon. Hypercalcemia may be a complication of leukemia, which leads to multiorgan metastatic calcification. Despite the absence of frank hypercalcemia, the presence of bone lesions suggests that the patient's calcinosis cutis was of the metastatic type. However, the cutaneous leukemic infiltrate may also represent a triggering factor for calcium deposition in the skin.