Prevalence of selected disorders of inborn errors of metabolism in suspected cases at a tertiary care hospital in Karachi.

OBJECTIVE

To study the prevalence of selected disorders of inborn errors of metabolism at a tertiary care hospital in Karachi by performing selective screening of high risk clinically suspected individuals.

METHODS

Cross sectional comparative study, was done at the Paediatric Endocrine Unit 2 of National Institute of Child Health Karachi in collaboration with Sapporo City Institute of Public Health, Japan. Sixty-two children age < 1 month-10 years meeting the inclusion criteria (Undiagnosed family history of similar illness or deaths, history of recurrent episodes of severe or persistent vomiting for which no infection or surgical cause was found and history of undiagnosed neurological symptoms and developmental delay) were enrolled in the study. Routine workup of inborn errors of metabolism was done in each child and their dried blood samples (DBS) and dried urine samples (DUS) were send to IEM Selective Screening Unit Japan. SPSS version 10 was used to derive results and p-value of < 0.05 was taken as statistically significant.

RESULTS

Out of 62 children, sixteen children (9 boys and 7 girls) were positive for inborn errors of metabolism (IEM). Respiratory distress (p = 0.042) and developmental delay (p = 0.048) were found to be the most common clinical presentations in our children. Out of 16 children with positive results, 14 children had history of death of siblings with similar complaints (p = 0.027). Consanguineous marriage was reported in 13 children. Among children with positive results 10 (62.5%) had organic acidemias, 1 (6.2%) had Ornithine Transcarbamylase (OTC) deficiency (Urea cycle defect) and 5 (31.2%) had congenital lactic acidemias.

CONCLUSION

Significant number of positive cases were seen in our series of patients, establishing the fact that IEM is prevalent in our population, though undiagnosed. Further such studies are needed on our side in future to determine incidence of metabolic disorders in Pakistan, which can be achieved by developing local facilities, neonatal screening programmes and collaboration with other countries who are actively working in this field.