Background: Biotinidase deficiency (BD) is a treatable inherited metabolic disorder included in the Italian expanded newborn screening program since 2017. We conducted the first national survey on BD management across Italian metabolic centres. Methods: A cross-sectional electronic survey was conducted among all Italian metabolic centres involved in newborn screening recall of BD. The questionnaire explored the main steps of BD management, from recall to long-term follow-up.Results: 22 Italian reference centres completed the survey, covering all centres nationwide involved in the clinical management of BD. Marked heterogeneity emerged across several steps of care. After an abnormal screening result, biotinidase activity was reassessed using different matrices: dried blood spot in 59.1% of centres, plasma in 22.7%, and serum in 18.2%. The timing of molecular testing also varied, with 40.9% of centres performing genetic analysis within 2 months and 18.2% after more than 5 months. Biotin treatment differed in both dosage and frequency. For profound BD, daily doses were 5 mg in 13.6%, 10 mg in 40.9%, and 20 mg in 45.5% of centres; treatment was given once daily in 45.5% and twice daily in 50.0%. For partial BD, 68.2% prescribed 5 mg and 31.8% 10 mg daily. Management of partial deficiency was particularly variable, especially regarding lifelong supplementation, follow-up intensity, and diagnostic re-evaluation. Despite this variability, most centres reported an absence of clinical symptoms among treated patients. Conclusions: This nationwide survey highlights substantial variability in the management of BD in Italy, particularly for partial deficiency, molecular testing, treatment regimens, and follow-up. These findings support the need for harmonized, evidence-based recommendations.
Current management of biotinidase deficiency following newborn screening in Italy: evidence from a clinical nationwide survey / Tagliaferri, F., Candela, E., Biasucci, G., Bonati, M.T., Bordugo, A., Concolino, D., Crescitelli, V., Daniotti, M., De Giovanni, D., Di Fiore, A., Di Michele, S., Dituri, F., Fiori, L., Gragnaniello, V., Guzzetti, C., La Rosa, A., La Spina, L., Martinelli, D., Nardecchia, F., Porta, F., et al.. - In: MOLECULAR GENETICS AND METABOLISM. - ISSN 1096-7192. - 149:3(2026). [10.1016/j.ymgme.2026.110264]
Current management of biotinidase deficiency following newborn screening in Italy: evidence from a clinical nationwide survey
Tagliaferri F.;Biasucci G.;De Giovanni D.;Martinelli D.;Porta F.;Santoro L.;
2026-01-01
Abstract
Background: Biotinidase deficiency (BD) is a treatable inherited metabolic disorder included in the Italian expanded newborn screening program since 2017. We conducted the first national survey on BD management across Italian metabolic centres. Methods: A cross-sectional electronic survey was conducted among all Italian metabolic centres involved in newborn screening recall of BD. The questionnaire explored the main steps of BD management, from recall to long-term follow-up.Results: 22 Italian reference centres completed the survey, covering all centres nationwide involved in the clinical management of BD. Marked heterogeneity emerged across several steps of care. After an abnormal screening result, biotinidase activity was reassessed using different matrices: dried blood spot in 59.1% of centres, plasma in 22.7%, and serum in 18.2%. The timing of molecular testing also varied, with 40.9% of centres performing genetic analysis within 2 months and 18.2% after more than 5 months. Biotin treatment differed in both dosage and frequency. For profound BD, daily doses were 5 mg in 13.6%, 10 mg in 40.9%, and 20 mg in 45.5% of centres; treatment was given once daily in 45.5% and twice daily in 50.0%. For partial BD, 68.2% prescribed 5 mg and 31.8% 10 mg daily. Management of partial deficiency was particularly variable, especially regarding lifelong supplementation, follow-up intensity, and diagnostic re-evaluation. Despite this variability, most centres reported an absence of clinical symptoms among treated patients. Conclusions: This nationwide survey highlights substantial variability in the management of BD in Italy, particularly for partial deficiency, molecular testing, treatment regimens, and follow-up. These findings support the need for harmonized, evidence-based recommendations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
