3-Methylglutaconic aciduria with normal hydratase. (Non-specific or type 3) 3a: with mainly neuro sx. 3b: with neonatal acidosis and severe hypoglycemia.
Incidence
Reported in ~ 30 pts
Clinical Characteristics
Progressive encephalopathy of unusual high severity, 50% present mainly neurologic sx (3a). The other 50% have neonatal acidosis & severe hypoglycemia (3b), non compatible with life in most instances.
Precipitants
no
Provocation Tests
3-Methylglutaconic aciduria with normal hydratase: Leucine loading (75 mg/kg/d in 4 equal dosis or 200 to 300 mg/kg) fails to rise the metabolites since only 2% to 20% of the dose is converted into organic acids.
Diagnostic Procedures
GC/MS