Biotinidase deficiency is a rare autosomal recessive condition in which the body is unable to break down the conjugated form of the vitamin B7 (biotin), resulting in low levels of available biotin.
Profound deficiency (<10% of normal level) is estimated at ~1:100,000 of newborns. Profound or partial deficiency (<30% of normal level) is estimated at ~1:60,000 newborns.
Symptoms usually present in infancy:
- seborrhoeic dermatitis
- conjunctivitis and mucositis
- erythematous rash
- hearing loss
- lactic acidaemia
Variable neurologic manifestations:
- diffuse cerebral and cerebellar atrophy on CT or MRI
- brainstem and spinal cord myelopathy
Treatment and prognosis
Improves with supplemental biotin, which helps with diagnosis.
Biotinidase deficiency meets the major criteria for newborn screening in multiple countries.
- 1. Raha S, Udani V. Biotinidase deficiency presenting as recurrent myelopathy in a 7-year-old boy and a review of the literature. Pediatr. Neurol. 2011;45 (4): 261-4. doi:10.1016/j.pediatrneurol.2011.06.010 - Pubmed citation
- 2. Wolf B. Biotinidase deficiency: "if you have to have an inherited metabolic disease, this is the one to have". Genet. Med. 2012;14 (6): 565-75. doi:10.1038/gim.2011.6 - Pubmed citation
- 3. Wolf B. Clinical issues and frequent questions about biotinidase deficiency. Mol. Genet. Metab. 2010;100 (1): 6-13. doi:10.1016/j.ymgme.2010.01.003 - Pubmed citation