Akinori Uruha1, Olivier Benveniste. 1. aUniversité Pierre et Marie Curie, Paris VI (UPMC), Institut National de la Santé et de la Recherche Médicale (INSERM), Unité Mixte de Recherche (UMR) 974, Centre de Recherche en Myologie, Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière (GHPS) bDépartement de Médecine Interne et Immunologie Clinique, UPMC, Assistance Publique - Hôpitaux de Paris, GHPS, INSERM UMR974, DHU I2B, and Centre de Référence des Pathologies Neuromusculaires Paris Est, Institut de Myologie, Paris, France.
Abstract
PURPOSE OF REVIEW: Sporadic late-onset nemaline myopathy (SLONM) with monoclonal gammopathy of undetermined significance (MGUS) is a rare subacute progressive muscle disease. The prognosis is poor due to severe respiratory insufficiency. Recently, however, autologous stem-cell transplantation following high-dose melphalan has been shown to be effective unless there is delay before the treatment. Therefore, early recognition of the disease is important. This review gives an overview of recent advances in SLONM-MGUS, which could help to understand clinical and pathological features and treatment. RECENT FINDINGS: Efficacy of autologous stem-cell transplantation following high-dose melphalan has been demonstrated in a long-term observation study. Subsequently, reports from other groups also have supported it. Furthermore, efficacy of chemotherapy toward plasma cell dyscrasia without stem-cell transplantation have been reported as well. A few case reports have suggested the presence of cardiac involvement related to SLONM-MGUS. SUMMARY: SLONM-MGUS is now considered as a treatable disease. Antiplasma cell dyscrasia therapy is a promising therapeutic option. Meanwhile, the pathomechanic link between muscle degeneration and monoclonal gammopathy remains unclear and further investigations are warranted.
PURPOSE OF REVIEW: Sporadic late-onset nemaline myopathy (SLONM) with monoclonal gammopathy of undetermined significance (MGUS) is a rare subacute progressive muscle disease. The prognosis is poor due to severe respiratory insufficiency. Recently, however, autologous stem-cell transplantation following high-dose melphalan has been shown to be effective unless there is delay before the treatment. Therefore, early recognition of the disease is important. This review gives an overview of recent advances in SLONM-MGUS, which could help to understand clinical and pathological features and treatment. RECENT FINDINGS: Efficacy of autologous stem-cell transplantation following high-dose melphalan has been demonstrated in a long-term observation study. Subsequently, reports from other groups also have supported it. Furthermore, efficacy of chemotherapy toward plasma cell dyscrasia without stem-cell transplantation have been reported as well. A few case reports have suggested the presence of cardiac involvement related to SLONM-MGUS. SUMMARY: SLONM-MGUS is now considered as a treatable disease. Antiplasma cell dyscrasia therapy is a promising therapeutic option. Meanwhile, the pathomechanic link between muscle degeneration and monoclonal gammopathy remains unclear and further investigations are warranted.