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
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.
