Maple Syrup Urine Disease

Maple syrup urine disease (MSUD), also called branched-chain ketoaciduria,
is an autosomal recessive metabolic disorder affecting branched-chain amino acids. It is one type of organic acidemia. The condition gets its name from the distinctive sweet odor of affected infants’ urine.

Types and Symptoms

The term Maple Syrup Urine Disease includes a range of classic and variant types of the disorder. The symptoms of classic MSUD are usually  vident within the first week of life and include a poor appetite, irritability, and the characteristic odor of the urine. Within days, the infants may lose their sucking reflex and grow listless, have a high-pitched cry, and become limp with episodes of rigidity. Without diagnosis and treatment, symptoms progress rapidly to seizures, coma, and death. Variant forms of MSUD are milder, but the symptoms can be severe during an illness and lead to a metabolic crisis. In variant types, failure to thrive may be the first symptom noticed.

Classification

Maple syrup urine disease can be classified by its pattern of signs and symptoms, or by its genetic cause. The most common and severe form of the disease is the classic type, which appears soon after birth. Variant forms of the disorder may appear later in infancy or childhood and are typically less severe, but still involve mental and physical problems if left untreated.

There are several variations of the disease:

• Classic Severe MSUD
• Intermediate MSUD
• Intermittent MSUD
• Thiamine-responsive MSUD
• E3-Deficient MSUD with Lactic Acidosis

Do you want to know more about MSUD? Contact the Clinic for Special Children (click here)