Biotinidase Deficiency

Biotinidase deficiency (BTD) is an inherited disorder caused by biallelic pathogenic variants in the BTD gene and affects approximately one in 60,000 people.  The deficiency in biotinidase enzymatic activity interferes with the body’s ability to recycle and reuse the vitamin biotin, resulting primarily in neurologic and dermatologic manifestations.   The disorder usually causes no symptoms in the first weeks or months of life,  and early signs and symptoms are frequently nonspecific.  Symptoms can develop once the biotin transferred from the mother to the child has been depleted. Hearing impairment, vision problems, and developmental delay are generally irreversible once they have occurred, even with biotin therapy; therefore, timely diagnosis is very important.   Early treatment can prevent all symptoms. Newborn screening for BTD is currently performed across the United States and in more than 30 other countries.  Confirmatory testing following an abnormal newborn screen for BTD involves serum testing to evaluate biotinidase activity and may include molecular testing of the BTD gene.  Laboratory testing may also be indicated in older patients who manifest symptoms that suggest the disease, and in cases of uncertain newborn screening results.

Tabs Content
Content Review: 
January 2020

Last Update: January 2020