Treatment of Multiple Carboxylase Deficiency is:
**Core Concept**
Multiple carboxylase deficiency (MCD) is a rare genetic disorder caused by a deficiency in the enzymes holocarboxylase synthetase (HCS) or biotinidase, which are essential for the activation and recycling of biotin, a crucial coenzyme for various carboxylation reactions in the body.
**Why the Correct Answer is Right**
The treatment of MCD involves supplementing the deficient enzyme activity, which can be achieved through biotin replacement therapy. Biotin is a water-soluble vitamin that serves as a coenzyme for carboxylation reactions, and its supplementation helps to alleviate the symptoms of MCD. The correct dosage and form of biotin should be prescribed by a healthcare professional to ensure effective treatment.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because vitamin B12, although essential for various metabolic processes, is not directly related to the treatment of MCD.
**Option B:** This option is incorrect because folic acid, although important for DNA synthesis and repair, is not used to treat MCD.
**Option C:** This option is incorrect because vitamin C, although important for collagen synthesis and immune function, is not used to treat MCD.
**Clinical Pearl / High-Yield Fact**
Early recognition and treatment of MCD with biotin supplementation can significantly improve the quality of life for affected individuals and prevent long-term complications, such as developmental delays and seizures.
**Correct Answer: D. Biotin.