An Audit of Biotinidase Deficiency among Children and Young People in a Scottish NHS Region between 2014 And 2016

Background: Some evidence-based guidelines have recommended biotinidase deficiency (BD) screening.for investigating children with moderate or severe global developmental delay. patients with residual BT activities >1% (partial BD) may remain asymptomatic even without treatment.

Objectives: We aimed to analyze the pattern and outcome of investigations for BTD among Community Pediatricians in a Mid-Eastern Scottish NHS Area.

Method: We retrospectively reviewed the clinical and laboratory data of all children throughout NHS Fife area screened for Biotinidase activity (BTA) over a two- year period between July 2014 and July 2016.

Biotinidase activity was measured in plasma using a colourimetric assay, by Spectrophotometric methods. Profound biotinidase deficiency is defined as levels

Results: A total of 262 tests were requested for 243 children aged between 1 and 153 months (Mean 70 months, SD 42 months, Median 60 months). 15 patients had their samples repeated once and two patients had their samples tested twice. 5 patients had BTA values below the reference value of 4. One of them on repeat increased from 2.7 to 3, while the other increased from 2.7 to 8.7 within two months. The remaining 3 patients had BTA values between 3 and 4 which were not repeated. Results of 191 patients were analysed with BTA ranging between 3 and 14.1. None of the patients had BT deficiency.

Conclusion: None of the patients studied had abnormal BTA results. However a substantial proportion of the patients’ samples 53 /244 (22%) could not be analysed in the laboratory due to various problems. A larger prospective study is required to verify the true prevalence of BTD in the population.