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Washington University Experience | MUSCLE | Myopathies with Mitochondrial Pathology | 19A1A (Case 19) Muscle_019 - Copy
Case 19 History ---- The patient is a 61-year-old woman presenting with progressive limb weakness and genetic testing showing a likely pathogenic variant in titin. Clinical NM Division workup history: A 61-year-old woman with progressive, proximal greater than distal, weakness, SSB antibodies, ANA of 1:320, aldolase of 5.6 and CK of 134. Myopathy 2 autoantibody testing was negative. Serum neurofilament light chain is 17 pg/mL. Electrodiagnostic testing showed a non-irritable myopathy. Genetic testing has shown a pathogenic variant in TTN and VUSs in COL6A2, GYS1 and RYR1. A prior biopsy reviewed here showed a chronic myopathy with abnormalities of internal architecture including sarcoplasmic pads, mitochondrial pathology, internal nuclei, type I predominance and enlarged endomysial capillaries. Another biopsy was performed to further characterize the abnormalities seen on the outside biopsy. Immune stains were requested. Procedure: Biopsy, Left deltoid muscle. ---- 19A1A-C In this biopsy there were minimal findings overall; however, this striking collection of small, dense serpiginous mitochondria were encountered. In the first image there is a second collection of Z band streaming with only rare mitochondriopathy. (electron micrographs)
