RESUMEN
BACKGROUND: Heart failure is a rare manifestation of neonatal hypocalcemia. This paper describes such a case resulting from maternal vitamin D deficiency. CASE REPORT: A full-term boy, born in December after a normal pregnancy, was admitted at the age of 6 weeks because of dyspnea that appeared during suckling. Examination showed heart failure. Electrocardiogram showed that the corrected QT-interval was lengthened (0.54 s, normal < 0.45 s). Echocardiogram showed dilated, hypokinetic myocardiopathy. His serum calcium concentration was low (1.40 mmol/l) and phosphate was high (2.8 mmol/l); his alkaline phosphatase was 513 Ul/l. His blood PTH concentration was high (120 pg/ml) and his 25 (OH) D was low (5 ng/ml). The patient was given calcium (1 g/m2/day) and 1.25 (OH)2 D (2 micrograms/day orally). His serum calcium returned to normal within 4 days, and his cardiac abnormality was resolved within 3 months. His mother's blood 25 (OH) D concentration was very low (3 ng/ml), 6 weeks after birth. CONCLUSION: Neonatal hypocalcemia appears to have been compounded in this case by a maternal vitamin D deficiency. Hence, all pregnant women at risk of deficiency should be given vitamin D.