CLINICAL AND LABORATORY APPROACH FOR THE DIAGNOSIS OF GALACTOSEMIA INAFRICA

A new method free from haemoglobin interference is described to measur e erythrocyte galactose-l-phosphate uridyltransferase(GALT) activity l evels. Since haemoglobin is removed by acid denaturation and precipita tion with chloroform, only a simple photometer is required to assay GA LT activity, implying that this method can be performed even when only basic laboratory facilities are available. Using this method, four in fants have been found to suffer from galactosaemia due to GALT deficie ncy. There children had very low, but still measurable GALT activities (<1.0 mumol glucose-l-phosphate formed/gHb/hr) while one child had no detectable erythrocyte GALT activity. Compared to the other three chi ldren, this latter infant was seriously ill and required intensive car e treatment before the diagnosis of galactosaemia was made. These resu lts confirm the existence of different GALT variants in galactosaemia, in which the variant with zero activity has the most serious clinical sequelae if not appropriately treated.