Biotin is a B-complex vitamin that is found in many foods. Dietary deficiency is uncommon and typically mild. Severe deficiency can occur but is rare and may indicate a hereditary defect in biotin metabolism.
Synonyms: vitamin H. vitamin B7
Common clinical manifestations may include:
(1) alopecia
(2) scaly, erythematous dermatitis distributed around body orifices
(2a) a scaly rash around the eyes, nose and mouth is referred as the biotin face
(3) neurologic findings (hypotonia, seizures, ataxias, numbness, tingling, lethargy)
(4) nausea, vomiting
Less common findings may include:
(5) susceptibility to cutaneous Candidiasis or other skin infection
(6) developmental delay in children
(7) psychiatric disorder (depression, hallucinations)
(8) conjunctivitis
(9) sensorineural hearing loss
(10) lactic acidosis or ketoacidosis
(11) optic atrophy
(12) anorexia
(13) encephalopathy
(14) reduced cerebral volume with ventriculomegaly
Differential diagnosis:
(1) zinc deficiency
(2) allergic dermatitis
(3) sodium-dependent multivitamin transporter defect
