Molybdenum cofactor deficiency in a Malaysian child

Area of Science:

• Biochemistry
• Genetics
• Neurology

Background:

• Molybdenum cofactor deficiency is a rare, autosomal recessive genetic disorder.
• It presents with severe neurological symptoms, often fatal in infancy, mimicking hypoxic-ischaemic insult.
• Symptoms include neonatal-onset encephalopathy, intractable seizures, and feeding/respiratory issues.

Observation:

• A case of an 8-year-old boy with severe neurological manifestations since birth, but without significant seizures, is presented.
• This presentation highlights the variability in clinical presentation, particularly the absence of seizures.
• The patient's neuroimaging findings were consistent with hypoxic-ischaemic encephalopathy.

Findings:

• Molybdenum cofactor deficiency should be considered in newborns with unexplained encephalopathy and imaging suggestive of hypoxic-ischaemic insult.
• Key diagnostic laboratory findings include low serum uric acid, positive urine sulfite tests, and elevated urinary S-sulfocysteine, hypoxanthine, and xanthine.
• This case underscores the importance of considering rare metabolic disorders in neonatal encephalopathy.

Implications:

• Early identification and diagnosis of molybdenum cofactor deficiency are critical for timely intervention.
• Recognizing this disorder can prevent misdiagnosis as hypoxic-ischaemic insult, allowing for appropriate management.
• This case expands the understanding of the clinical spectrum of molybdenum cofactor deficiency.