119: 3-HYDROXY 3-METHYL-GLUTARYLCO-ALYASE DEFICIENCY

Abstract

An 8 month old Arab boy was investigated for recurrent attacks of hypoglycemia occurring during intercurrent infections, which were associated with metabolic acidosis and on one occasion with transient abormal liver function tests. Parents are first cousins. A sibling suffered from similar manifestations and succumbed at 2 years. The patient tolerated an 18 hour fast without evidence of hypoglycemia nor did he become ketonemic. His serum carnitine was total 15 and free 12 nmol/l. Treatment included oral carnitine, a high CHO low fat and protein diet. After stopping carnitine, the patient went into coma with metabolic acidosis from which he recovered slowly with iv glucose and electrolytes. Gaschromatographic/mass spectrometry analysis of his urinary organic acids revealed abnormal peaks identified as glutaric acid, methylglutaric acid, 3-methylglutaconic acid and 3-OH-3-methylglutaric acid, fibroblast 3-OH-3-methyl glutaryl CoA lyase activity was 0.1 (normal 22.1 + 6.7)nmol/min/mg prot. This is the first patient with HMG CoA lyase deficiency described in Israel. The Authors are indebted to Dr.D. Abeliovitz for tissue cultures and Dr A.J.Wanders for determining fibroblast enzyme activity.