Causes Maple syrup urine disease has an autosomal recessive pattern of inheritance. Additionally, MSUD patients experience an abnormal course of diseases in simple infections that can lead to permanent damage. Death from cerebral edema will likely occur if there is no treatment. Untreated in older individuals, and during times of metabolic crisis, symptoms of the condition include uncharacteristically inappropriate, extreme or erratic behavior and moods, hallucinations, lack of appetite, weight loss, anemia, diarrhea, vomiting, dehydration, lethargy, oscillating hypertonia and hypotonia, ataxia, seizures, hypoglycaemia, ketoacidosis, opisthotonus, pancreatitis, rapid neurological decline, and coma.

The symptoms of MSUD may also present later depending on the severity of the disease. Symptoms associated with thiamine-response MSUD are similar to intermediate MSUD. Metabolic crisis leading to seizures, coma, and brain damage is still a possibility. Symptoms of lethargy and characterized odor of maple syrup will occur when the individual experiences stress, does not eat, or develops an infection. Intermittent MSUDĬontrary to classic and intermediate MSUD, intermittent MSUD individuals will have normal growth and intellectual development. Symptoms associated with classic MSUD also appear in intermediate MSUD. The majority of children with intermediate MSUD are diagnosed between the ages of 5 months and 7 years. Intermediate MSUD has greater levels of residual enzyme activity than classic MSUD. Additional signs and symptoms that can be associated with classic MSUD include intellectual limitation and behavioral issues. Although MSUD can be stabilized, there are still threats of metabolic decompensation and loss of bone mass that can lead to osteoporosis, pancreatitis, and intracranial hypertension. If MSUD is left untreated, central neurologic function and respiratory failure will occur and lead to death.

These neurologic signs include athetoid, hypertonia, spasticity, and opisthotonus that lead to convulsions and coma. The infant will then experience increased focal neurologic signs. Subtle symptoms include poor feeding, either bottle or breast, lethargy, and irritability. Infants with classic MSUD will display subtle symptoms within the first 24–48 hours. Symptoms of MSUD varies between patients and is greatly related to the amount of residual enzyme activity. In populations to whom maple syrup is unfamiliar, the aroma can be likened to fenugreek, and fenugreek ingestion may impart the aroma to urine. The smell is also detected in ear wax of an affected individual during metabolic crisis. The disease is named for the presence of sweet-smelling urine, similar to maple syrup, when the person goes into metabolic crisis. It was described by John Menkes in the 1950s. The condition gets its name from the distinctive sweet odor of affected infants' urine and earwax, particularly prior to diagnosis and during times of acute illness. Maple syrup urine disease ( MSUD) is an autosomal recessive metabolic disorder affecting branched-chain amino acids. Leucine (pictured above), Isoleucine, and valine are the branched-chain amino acids that build up in MSUD. Medical condition Maple syrup urine disease

Maple syrup urine disease other names