Clinical, Biochemical and Outcome Profile of Biotinidase Deficient Patients from Tertiary Centre in Northern India.

INTRODUCTION Biotinidase deficiency is an inherited metabolic disorder with estimated birth incidence of 1 in 61,000 for profound and partial deficiency. Estimated incidence of profound and partial biotinidase deficiency is 1 in 1, 37,000 and 1 in 1, 10,000 respectively. The carrier frequency in general population is 1 in 120. We attempt to study clinical, biochemical and outcome from 10 Biotinidase deficient patients. MATERIALS AND METHODS A retrospective case record study was conducted to record Clinical, biochemical and outcome profile from genetic records. Biotinidase level was measured using spectrophotometric method. RESULTS Study group comprised of 8 males and 2 females with median age of presentation 6 (2-45.75) months. Median (interquartile range) Biotinidase level in study group 0.3 (0.08-1.5) nmol/ml/min. Study group was further divided in to early onset group (< 12 months, n-6) and late onset group (> 12 months, n-4). Seizure, alopecia and hearing loss were predominant phenotypes in study group. The other rare presentations were: hypotonia, ataxia, skin rash, seborrhoea. The most common seizure type was focal seizure. Control of seizure activity was important immediate outcome measured in study group. Median duration (interquartile range) of seizure control in early onset group was 3 (2-4)days against 13.5 (12.25-14.75) days in late onset group. CONCLUSION This study highlights the need of early diagnosis for favourable outcome for a potentially treatable inherited metabolic disorder.

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