Molybdenum cofactor deficiency

Molybdenum cofactor deficiency
Synonyms	MoCD
Pronounce	N/A
Specialty	N/A
Symptoms	Seizures, developmental delay, feeding difficulties, neurological deterioration
Complications	N/A
Onset	Neonatal
Duration	Lifelong
Types	N/A
Causes	Genetic mutation
Risks	Consanguinity
Diagnosis	Genetic testing, biochemical analysis
Differential diagnosis	Sulfite oxidase deficiency, Leigh syndrome
Prevention	N/A
Treatment	Supportive care, experimental therapies
Medication	N/A
Prognosis	Poor
Frequency	Rare disease
Deaths	N/A

Molybdenum cofactor deficiency is a rare metabolic disorder characterized by the inability to synthesize the molybdenum cofactor, a vital component for the function of certain enzymes in the body. This deficiency leads to a buildup of toxic substances and results in severe neurological damage.

Pathophysiology

The molybdenum cofactor is essential for the activity of several enzymes, including sulfite oxidase, xanthine dehydrogenase, and aldehyde oxidase. These enzymes play critical roles in the metabolism of sulfur-containing amino acids and purines. In molybdenum cofactor deficiency, the lack of functional cofactor results in the accumulation of sulfite, xanthine, and other toxic metabolites, leading to neurological damage and other systemic effects.

Genetics

Molybdenum cofactor deficiency is an autosomal recessive disorder, meaning that an affected individual must inherit two defective copies of the gene, one from each parent. The condition is caused by mutations in one of several genes involved in the biosynthesis of the molybdenum cofactor, including MOCS1, MOCS2, and GPHN.

Clinical Presentation

Symptoms of molybdenum cofactor deficiency typically appear in the neonatal period or early infancy. Affected infants may present with severe seizures, developmental delay, poor feeding, and hypotonia. As the disease progresses, neurological deterioration continues, often leading to microcephaly and spasticity.

Diagnosis

Diagnosis of molybdenum cofactor deficiency is based on clinical presentation, biochemical testing, and genetic analysis. Elevated levels of sulfite and xanthine in the urine, along with low levels of uric acid, are indicative of the disorder. Genetic testing can confirm mutations in the genes responsible for molybdenum cofactor synthesis.

Treatment

Currently, there is no cure for molybdenum cofactor deficiency. Treatment is primarily supportive and focuses on managing symptoms and preventing complications. In some cases, supplementation with cyclic pyranopterin monophosphate (cPMP), a precursor of the molybdenum cofactor, has shown promise in reducing symptoms and improving outcomes.

Prognosis

The prognosis for individuals with molybdenum cofactor deficiency is generally poor, with most affected individuals experiencing severe neurological impairment and reduced life expectancy. Early diagnosis and intervention may improve quality of life and extend survival.

Related pages

• Metabolic disorder
• Enzyme
• Genetic disorder
• Neurological disorder