There are several metabolic functions that are affected by biotinidase deficiency, a rare genetic disorder in which the body is unable to properly process it. This overview describes its causes, symptoms, diagnosis, treatment, and prevention.
Mutations in the BTD gene cause biotinidase deficiency, which is responsible for recycling biotin in the body with the help of the enzyme biotinidase. In the absence of this enzyme, the body cannot efficiently utilize or recycle biotin from dietary sources or from proteins, leading to a biotin deficiency.
Biotinidase deficiency can cause a variety of symptoms, including:
There may be a red, scaly rash around the eyes, nose, mouth, and genital area.
Alopecia: The hair may thin or fall out (alopecia).
There may be neurological manifestations such as seizures, developmental delays, hypotonia (low muscle tone), ataxia (lack of coordination), and intellectual disability.
In severe cases, respiratory difficulties, such as hyperventilation, apnea (breathing pauses), and respiratory infections may occur.
There may be vision abnormalities such as optic atrophy (damage to the optic nerve) or decreased vision.
Infants may experience digestive issues such as vomiting, diarrhea, or feeding difficulties.
As a result of impaired metabolism, acidic compounds accumulate in the blood (metabolic acidosis).
The diagnosis of biotinidase deficiency typically involves clinical evaluation, biochemical testing, and genetic testing. Key diagnostic steps may include:
Blood spot testing is used in many countries to detect biotinidase deficiency in newborns.
To confirm deficiency, blood or serum samples are tested for biotinidase enzyme activity.
To confirm the diagnosis and assess carrier status, DNA analysis is performed to identify mutations in the BTD gene.
Evaluation of symptoms, medical history, and family history of metabolic disorders.
As a treatment for biotinidase deficiency, oral biotin (vitamin B7) is used to maintain adequate levels of biotin in the body throughout life. Symptoms and complications associated with biotin deficiency can be effectively managed with biotin supplementation. Dosage recommendations may vary depending on how severe the deficiency is and the individual characteristics of the patient.
In order to prevent biotinidase deficiency, newborn screening programs are used and biotin supplementation is initiated promptly. In order to assess whether the condition is likely to be passed along to future generations, individuals with a family history of biotinidase deficiency may be recommended to receive genetic counseling. The public and healthcare professionals can also be informed about the importance of newborn screening for metabolic disorders to ensure timely diagnosis and intervention.
A biotinidase deficiency is a rare genetic disorder characterized by an inability for the body to properly process biotin, causing a variety of symptoms affecting the skin, hair, nervous system, and other organs. The condition must be diagnosed early and treated lifelong with biotin supplementation in order to prevent complications and manage it. At-risk individuals may benefit from genetic counseling to assess the risk of passing the condition on to their children.
