Increased prevalence of hereditary metabolic diseases among native Indians in Manitoba and northwestern Ontario.

OBJECTIVE

To compare the prevalence of hereditary metabolic diseases in the native and non-native populations of Manitoba and northwestern Ontario.

DESIGN

Retrospective analysis.

SETTING

Children's Hospital, Winnipeg.

PATIENTS: Patients were selected by three methods: laboratory tests designed to screen patients suspected of having a metabolic disease, laboratory investigation of newborn infants with abnormalities detected through screening, and investigation of near relatives of probands with disease.

RESULTS

A total of 138 patients with organic acid, amino acid and carbohydrate disorders were seen from 1960 to 1990. Of these, 49 (36%) were native Indians (Algonkian linguistic group). This was in sharp contrast to the proportion of native Indians in the total study population (5.8%). Congenital lactic acidosis due to pyruvate carboxylase deficiency (13 patients), glutaric aciduria type I (14 patients) and primary hyperoxaluria type II (8 patients) were the most common disorders detected. Other rare disorders included glutaric aciduria type II (one patient), 2-hydroxyglutaric aciduria (one patient) and sarcosinemia (one patient). Underreporting, especially of glutaric aciduria type I and hyperoxaluria type II, was likely in the native population.

CONCLUSIONS

Hereditary metabolic diseases are greatly overrepresented in the native population of Manitoba and northwestern Ontario. We recommend that native children who present with illnesses involving disturbances of acid-base balance or with neurologic, renal or liver disease of unknown cause by investigated for a possible metabolic disorder.