Transient neonatal renal failure and massive polyuria in MEGDEL syndrome

BACKGROUND MEGDEL (3-methylglutaconic aciduria with deafness, encephalopathy, and Leigh-like syndrome) syndrome is a mitochondrial disorder associated with recessive mutations in SERAC1. OBJECTIVES To report transient neonatal renal findings in MEGDEL syndrome. RESULTS This 7 year-old girl was the first child of consanguineous Turkish parents. She exhibited an acute neonatal deterioration with severe lactic acidosis and liver failure. Initial evaluation revealed massive polyuria and renal failure with 3-methylglutaconic aciduria. Symptoms and biological findings progressively improved with symptomatic treatment but lactic acidosis and high lactate to pyruvate ratio along with 3-methylglutaconic aciduria persisted. At 8 months of age, a subacute neurological degradation occurred with severe hypotonia, dystonia with extrapyramidal movements and failure to thrive. Brain MRI revealed basal ganglia lesions suggestive of Leigh syndrome. At 3 years of age, sensorineural deafness was documented. MEGDEL syndrome was further confirmed by the identification of an already reported homozygous mutation in SERAC1. CONCLUSION Transient neonatal polyuria and renal failure have not been reported to date in SERAC1 defective patients. Such neonatal kidney findings expand the clinical spectrum of MEGDEL syndrome.