Echocardiography monitoring for diazoxide induced pericardial effusion.

1 of 2 DESCRIPTION A 3-year-old boy with Down’s syndrome with no underlying cardiac anomalies presented with hypoglycaemia due to congenital hyperinsulinism (CHI). He received treatment with oral diazoxide (Proglycem) (10 mg/kg/day), along with the diuretic chlorothiazide, which ensured glycaemic stability. However, a large pericardial effusion ( fi gure 1A ) requiring drainage was noted within a month. Diazoxide was discontinued and second line treatment with octreotide was commenced. Despite large doses (30 μg/kg/ day), glycaemic control remained unsatisfactory. A further trial of diazoxide was undertaken, pending a decision for subtotal pancreatectomy. Diazoxide was introduced at 1 mg/kg/day and increased to 4 mg/kg/day (low dose) by 2 weeks with satisfactory glycaemic control. However, serial weekly echocardiography detected minimal pericardial effusion ( fi gure 1B ) without overt features of cardiovascular instability. Withdrawal of diazoxide therapy led to resolution of the pericardial effusion. Euglycaemia was achieved by subtotal pancreatectomy. Diazoxide is commonly used as fi rst line treatment for CHI. Diazoxide can cause fl uid retention 1 and cardiovascular adverse events. 2