P80 – 2638: Molybdenum cofactor and isolated sulphite oxidase deficiencies in Egyptian children: Report of 6 cases

Abstract

Objective To describe the clinical, biochemical and molecular genetic findings in Egyptian children with Molybdenum Cofactor and isolated sulfite oxidase deficiencies, for the first time in Egypt. Methods Six Egyptian patients from different pedigrees with confirmed Molybdenum co Factor or isolated sulfite oxidase deficiencies were included in the study. All the patients were subjected to a thorough general and neurologic examination, expanded metabolic screen and urine organic acid profile, brain MRI and quantitation of S-sulphocysteine and xanthine in urine by LC-Ms/Ms and 5/6 patients had molecular analysis for MCOS1 gene. Results All six patients presented with intractable seizures immediately after birth. Microcephaly, severe neurodevelopmental delay, swallowing dysfuction, axial hypotonia, spastic quadriparesis, hyperekeplexia, characteristic craniofacial abnormalities as narrow bifrontal diameter and deeply seated eyes was present in all 6 patients. Extraneurologic manifestations in the form of hypertrophic cardiomyopathy, and xanthine stones was detected in one patient each, both suffering from MCO deficiency. two patients were diagnosed biochemicaly as isolated sulphite oxidase deficiency and four patients with molybdenum cofactor deficiency. MRI of all patients was characterized by multiple severe volume loss & subcortical cysts. The common mutation detected was MCOS1. Conclusion Molybdenum co factor and sulphite oxidase deficiencies are a diagnosable inborn errors of metabolism. Brain MRI is crucial in pointing to the diagnosis by the presence of multiple cortical cysts simulating hypoxic cystic encephalomalacia.