Purpose: To highlight the diagnostic relevance of mitochondrial DNA (mtDNA) mu tation analysis in acquired juvenile unilateral upper eyelid ptosis. Methods: A1 3-year-old boy presented with acquired, slowly progressiv...Purpose: To highlight the diagnostic relevance of mitochondrial DNA (mtDNA) mu tation analysis in acquired juvenile unilateral upper eyelid ptosis. Methods: A1 3-year-old boy presented with acquired, slowly progressive unilateral ptosis. We performed ophthalmological and neurological examinations, laboratory testing, skeletal muscle biopsy including histological and histochemical investigations, biochemical analysis of respiratory chain enzymes in skeletal muscle homogenate and molecular genetic testing of skeletal muscle DNA. Results: Though clinical, laboratory, histological and biochemical analyses did not reveal any hints sugg esting a mitochondrial cytopathy, molecular genetic testing by Southern blot ana lysis of total DNA from skeletal muscle tissue showed a 5.8 kb mtDNA deletion th us proving the diagnosis of mitochondrial chronic progressive external ophthalmo plegia(CPEO). Conclusions: In patients with unexplained acquired juvenile unilat eral ptosis, an underlying mitochondrial cytopathy should be considered even in cases of inconspicuous ancillary examinations comprising skeletal muscle histolo gy and biochemistry. To establish the diagnosis, molecular genetic testing of DN A derived from skeletal muscle tissue is essential in those patients.展开更多
Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochond rial cytopathy presenting with ptosis and external ophthalmoparesis. Mitochondri al disorders are characterized by a broad clinical spectr...Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochond rial cytopathy presenting with ptosis and external ophthalmoparesis. Mitochondri al disorders are characterized by a broad clinical spectrum and genetic backgrou nd with marked genotype/phenotype variability. The routine diagnostic work-up u sually includes clinical and laboratory examinations as well as histological and histochemical analysis of skeletal muscle biopsy. In our case only an additiona l molecular biological examination allowed the diagnosis of CPEO. Patient and Me thods: We report a 35-year-old woman with a 7-years history of slowly progres sive diplopia due to impaired ocular motility and bilateral ptosis. We performed ophthalmological and neurological examinations, laboratory testing, lower limb skeletal muscle biopsy including histo logical and histochemical investigations, biochemical analysis of respiratory ch ain enzymes in skeletal muscle homogenate and molecular genetic testing of skele tal muscle DNA. Results: Although clinical, laboratory, histological and biochem ical analyses did not give any hints suggesting a mitochondrial cytopathy, molec ular genetic testing of total DNA from skeletal muscle tissue by Southern blot a nalysis finally revealed a 3.8 kb mitochondrial DNA deletion with a degree of he teroplasmy of 45%. Conclusions: In patients with unexplained binocular diplopia , oculomotor deficits and/or acquired ptosis, an underlying mitochondrial cytopa thy should be considered. Even in the case of inconspicuous skeletal muscle hist ology and biochemistry, molecular genetic testing of skeletal muscle DNA is advi sable in order to establish the diagnosis.展开更多
文摘Purpose: To highlight the diagnostic relevance of mitochondrial DNA (mtDNA) mu tation analysis in acquired juvenile unilateral upper eyelid ptosis. Methods: A1 3-year-old boy presented with acquired, slowly progressive unilateral ptosis. We performed ophthalmological and neurological examinations, laboratory testing, skeletal muscle biopsy including histological and histochemical investigations, biochemical analysis of respiratory chain enzymes in skeletal muscle homogenate and molecular genetic testing of skeletal muscle DNA. Results: Though clinical, laboratory, histological and biochemical analyses did not reveal any hints sugg esting a mitochondrial cytopathy, molecular genetic testing by Southern blot ana lysis of total DNA from skeletal muscle tissue showed a 5.8 kb mtDNA deletion th us proving the diagnosis of mitochondrial chronic progressive external ophthalmo plegia(CPEO). Conclusions: In patients with unexplained acquired juvenile unilat eral ptosis, an underlying mitochondrial cytopathy should be considered even in cases of inconspicuous ancillary examinations comprising skeletal muscle histolo gy and biochemistry. To establish the diagnosis, molecular genetic testing of DN A derived from skeletal muscle tissue is essential in those patients.
文摘Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochond rial cytopathy presenting with ptosis and external ophthalmoparesis. Mitochondri al disorders are characterized by a broad clinical spectrum and genetic backgrou nd with marked genotype/phenotype variability. The routine diagnostic work-up u sually includes clinical and laboratory examinations as well as histological and histochemical analysis of skeletal muscle biopsy. In our case only an additiona l molecular biological examination allowed the diagnosis of CPEO. Patient and Me thods: We report a 35-year-old woman with a 7-years history of slowly progres sive diplopia due to impaired ocular motility and bilateral ptosis. We performed ophthalmological and neurological examinations, laboratory testing, lower limb skeletal muscle biopsy including histo logical and histochemical investigations, biochemical analysis of respiratory ch ain enzymes in skeletal muscle homogenate and molecular genetic testing of skele tal muscle DNA. Results: Although clinical, laboratory, histological and biochem ical analyses did not give any hints suggesting a mitochondrial cytopathy, molec ular genetic testing of total DNA from skeletal muscle tissue by Southern blot a nalysis finally revealed a 3.8 kb mitochondrial DNA deletion with a degree of he teroplasmy of 45%. Conclusions: In patients with unexplained binocular diplopia , oculomotor deficits and/or acquired ptosis, an underlying mitochondrial cytopa thy should be considered. Even in the case of inconspicuous skeletal muscle hist ology and biochemistry, molecular genetic testing of skeletal muscle DNA is advi sable in order to establish the diagnosis.
