Differential Diagnosis for a 7-year-old Male with Progressive Hypopigmented Lesions, Acroparesthesia, and Hypoketotic Hypoglycemia

• Single Most Likely Diagnosis

  • Maple Syrup Urine Disease (MSUD): This condition is characterized by hypopigmented skin lesions, neurological symptoms such as acroparesthesia, and metabolic disturbances including hypoketotic hypoglycemia. The disease is caused by a deficiency in the branched-chain alpha-keto acid dehydrogenase complex, leading to the accumulation of branched-chain amino acids and their toxic byproducts.

• Other Likely Diagnoses

  • Tyrosinemia Type 1: This genetic disorder affects the metabolism of tyrosine, leading to the accumulation of toxic compounds. It can cause hypopigmentation, neurological symptoms, and hypoketotic hypoglycemia due to liver dysfunction.
  • Glycogen Storage Disease Type 1: Although primarily known for its effects on glycogen metabolism, this disease can lead to hypoglycemia and has been associated with skin manifestations and neurological symptoms in some cases.

• Do Not Miss Diagnoses

  • Methylmalonic Acidemia: A disorder of amino acid metabolism that can lead to severe metabolic acidosis, hypoketotic hypoglycemia, and neurological symptoms. Early diagnosis is crucial for management and preventing long-term complications.
  • Propionic Acidemia: Similar to methylmalonic acidemia, this condition involves a defect in amino acid metabolism, leading to the accumulation of toxic compounds. It can cause severe illness, including hypoglycemia and neurological deterioration.

• Rare Diagnoses

  • Hawkinsinuria: A rare disorder of amino acid metabolism that can lead to episodes of acute illness characterized by hypoketotic hypoglycemia, metabolic acidosis, and organic aciduria. Skin and neurological manifestations can occur but are less commonly highlighted.
  • Biotinidase Deficiency: Although primarily known for its dermatological, neurological, and immunological manifestations, biotinidase deficiency can lead to metabolic disturbances, including hypoglycemia, especially if left untreated.