Late Onset Subacute Profound Biotinidase Deficiency Caused by a Novel Homozygous Variant c.466-3T>G in the BTD Gene

Abstract
Biotinidase defciency (BD) is an autosomal recessive disorder caused by bi-allelic mutation in the BTD gene. Clinical manifestations in BD mainly depends on residual biotinidase enzyme activity, although there are some exceptions. Broadly BD disorders are classifed as profound BD and partial BD. Further profound BD can be early onset, late onset, and sometimes may be asymptomatic. Clinically late-onset profound BD can present with spectrum of manifestations ranging from single organ to multiple organ involvement, typically afecting function of brain, eye, ear, and skin. Here, a frst-born child to consanguineous parents with late-onset profound BD presenting with hyperventilation secondary to lactic acidosis, hypotonia, evolving spasticity, and abnormal neuroimaging fndings caused by novel homozygous variant, c.466-3T>G in the BTD gene is reported.
Description
Keywords
Biotinidase defciency, Hyperventilation, Weakened splice variant, 3-hydroxyisovalerate, Lactic acidosis
Citation
Mohite Kaustubh, Nair Karthik Vijay, Sapare Anilkumar, Bhat Venkatraman, Shukla Anju, Kekatpure Minal, Patil Siddaramappa J.. Late Onset Subacute Profound Biotinidase Deficiency Caused by a Novel Homozygous Variant c.466-3T>G in the BTD Gene. Indian Journal of Pediatrics. 2022 Jun; 89(6): 594–596