1 - Pediatric Neurology Department, Hospital Dona Estefânia, Centro Hospitalar Lisboa Central, E.P.E.;
2 - Metabolic Diseases Unit, Hospital Dona Estefânia, Centro Hospitalar Lisboa Central, E.P.E.
- AnnualSymposiumof SSIEM, Birmingham, 5 de Setembro de 2012.
- Abstract publicado no JournalofInheritedMetabolicDisease, vol 35 Suppl 1, de Setembro de 2012.
Background: Sulfite oxidase deficiency (SOD) is an autosomal recessive inherited disease, usually presenting in the neonatal period with severe neurological symptoms including seizures, often refractory to anticonvulsant therapy, and a rapidly progressive encephalopathy leading to a state resembling that of neonatal hypoxic ischemia, with premature death. Most patients develop dislocated ocular lenses. Later or milder presentations of SOD are being reported with increasing frequency. These presentations include neurological regression with loss of previously acquired milestones or movement disorders.
Case report: We report a four year old girl presenting with intermittent ataxia and uncoordinated limb movements. A similar episode of ataxia had occurred previously one year before, with complete neurologic recovery and normal developmental milestones. Bilateral lens dislocation was recently diagnosed. Cranial MRI demonstrated bilateral globuspallidus enhancement. Sulfitest was positive. Further investigation led to the confirmation of isolated sulfite oxidase deficiency, with no enzyme activity detected on skin fibroblast culture. Molecular studies are ongoing.
Discussion: This case illustrates the clinical variability of SOD and is not only atypical but also seems to be the mildest form described so far. The association of ectopialentis with a movement disorder, even without psychomotor regression, should prompt us to look for this diagnosis.
Keywords: sulfite oxidase deficiency, clinical presentation.