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Clinical, biochemical and Genetic Spectrum of Mitochondrial disorders in Egyptian Children: A Study of 15 cases
Last modified: 2014-04-03
Abstract
IntroductionMitochondrial encephalomyopathies are a growing group ofdiseases with a large variety of clinical presentations ranging from a well defined clinical syndromes to non specific manifestations asfailure to thrive, hypotonia, seizures, global developmental delay,cardiomyopathy, visual or hearing loss.The objective of this study is to describe the clinical,biochemical and genetic spectrum of 15 Egyptian patients with confirmed mitochondrial respiratory chaindisorder .Subjects andMethods: This is a retrospectivestudy which included 62 patients with and age ranging from 9 months-25 yearsreferred to the neurometabolic Unit at Cairo University children Hospital forevaluation for a possible mitochondrial respiratory chain disorder. They were 35 males/27 females. All patientswere subjected to thorough neurological examination, basic lab investigations, expandedmetabolic screen and urine organic acid profile, muscle biopsy subjected toimmunohistopathological stain by COX and SDH,and respiratory chain complexes were assayed spectrophotometrically using specific substrates, and moleculardiagnosis for mitochondrial syndrome.Results 15/62 patients has been confirmed with respiratory chaindisorders. Three patients were diagnosed as MNGIE,one patient with MELAS, onepatient with mitochondrial depletion syndrome,one patient with mitochondrialmyopathy,5 patients with complex I deficiency(1/5 presenting as biotinresponsive striatal necrosis), 2 patients with combined complex 1&IVdeficiency,2 patients with LHON.Conclusion :Mitochondrial disorders have a wide spectrum of clinical presentations accountingfor the marked delay in the diagnosis. High degree of suspicion is necessary to start a comprehensive work up combining clinical, biochemical, pathological and molecular data to confirm the diagnosis
Keywords
mitochondrial respiratory chain disorders, complex 1, VI deficiency
References
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