CLINICAL PRESENTATION AND OUTCOME IN PRIMARY FAMILIAL HYPOMAGNESEMIA

The clinical presentation and long term outcome (mean follow up eight years, range 0.25 to 21) of 15 patients with autosomal recessive prima ry familial hypomagnesaemia is described. The most common (67%) presen ting events were generalised hypocalcaemic-hypomagnesaemic seizures at a mean (SD) age of 4.9 (2.5) weeks. Thirteen infants, treated soon af ter diagnosis with high dose enteral magnesium developed normally. The ir serum calcium returned to normal concentrations but serum magnesium could not be maintained at normal concentrations (0.53 (0.12 SD) mmol /l; normal >0.62). Delay in establishing a diagnosis led to a convulsi ve disorder with permanent neurological impairment in two infants. Rep orted complications of prolonged hypomagnesaemia such as renal stones, hypertension, arrhythmias, sudden death, or dyslipidaemia were not ob served.