Hereditary rimmed vacuole myopathy showing interstitial amyloid deposition in muscle tissue

Abstract

We describe a consanguineous family that had progressive myopathy with rimmed vacuole (RV) formation and amyloid deposition. Patient 1 is a 71-year-old woman with muscle atrophy in the lumbar girdle and lower extremities. Patient 2 is a 40-year-old man (the son of Patient 1) with fatty changes in the biceps femoris muscles. Muscle biopsies revealed myopathic and neurogenic degeneration with RV, necrotic fibers, and interstitial amyloid deposition. Amyloid deposition was detected only in the muscle tissue.

Sporadic late onset nemaline myopathy and immunoglobulin deposition disease

“…Light and heavy chain deposition in SLONM in a similar pattern leads to the suspicion that such a continuum might comprise SLONM as another disease that may be initiated by light and heavy chain deposition rather than nemaline bodies. Interestingly, amyloid deposition can be found in several other myopathies, including dysferlinopathy, hereditary distal myopathy with rimmed vacuoles, and inclusion body myositis …”

“…Interestingly, amyloid deposition can be found in several other myopathies, including dysferlinopathy, hereditary distal myopathy with rimmed vacuoles, and inclusion body myositis. 31,32 As SLONM, LCDD, LHCDD, and amyloid myopathy often respond to immunoablative therapy aimed at elimination of clonal plasma cells, similar therapeutic approaches might be used. Our patient's strength slowly but significantly improved after therapy with bortezomib/dexamethasone, a therapeutic regimen that has been shown to be effective in patients with LCDD.…”

Biochemical analysis of deposited amyloid fibrils—Analysis of amyloid protein extracted from small biopsy samples

“…し，肝移植前後で沈着アミロイド組成に変化が起こってい ることを証明した (Fig. 4 11) ) ． 以上，今回我々が提示した微小生検組織を用いた生化学 的診断法は，アミロイドーシスの診断に非常に有用な手法 であった．ただし，生検組織内のアミロイド沈着量が非常 に微量な場合，アミロイド線維を同定できなかった症例も 経験しており 12) ，今後はさらに，tissue-microdissection 法 などを用いて，より純粋なアミロイド線維を抽出するなど の解析法の向上に努めたいと考えている． 文 献…”