LAUSR

This study aimed to determine the clinical spectrum and biochemical findings on urine organic acids (UOA) in Biotin-responsive multiple carboxylase deficiency (MCD) patients presenting to the biochemical genetics laboratory (BGL). Patients reported as MCD, from January 2013-December 2020 were included. The UOA was analysed by gas chromatography mass spectrometer. Demographic, clinical, and biochemical details were extracted from the BGL history form. Two hundred and two patients were reported to have biotin responsive MCD with 111(55%) males and a median (Q3-Q1) age of 7 months (13-4). Of these 71.7% (n=145) patients presented in infantile period. Parental consanguinity was observed in 80% (n=161) and another 32.6% (n=66) cases grandparents were cousins. The main presenting features were seizures, developmental delay, and lethargy. The common peaks were determined on UOA 3OHIVA, MC and MCC. MCD is not rare in Pakistani population; it is recommended to include this disorder in newborn screening programs. Key Words: Biotin responsive multiple carboxylase deficiency, Organic acids, Amino acids, Pakistan, Inborn errors of metabolism.