非肌性肌球蛋白重链9基因相关疾病（nonmuscle myosin heavy chain 9 related disease，MYH9-RD）是MYH9基因突变引起的遗传性血小板减少性疾病，为常染色体显性遗传。患儿自出生起即表现为巨大血小板减少症，症状常伴随终生。通常表现...非肌性肌球蛋白重链9基因相关疾病（nonmuscle myosin heavy chain 9 related disease，MYH9-RD）是MYH9基因突变引起的遗传性血小板减少性疾病，为常染色体显性遗传。患儿自出生起即表现为巨大血小板减少症，症状常伴随终生。通常表现为轻微出血症状，但因临床对该病认识不足，患儿常被漏诊或误诊为慢性免疫性血小板减少性紫癜（ITP），给予不必要甚至有害的治疗，造成不良预后。为避免这种情况发生，本文就儿童MYH9-RD诊断治疗进展做一阐述。展开更多
Background: Laing early onset distal myopathy (MPD1) is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYH7. It is allelic with myosin storage myopath...Background: Laing early onset distal myopathy (MPD1) is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYH7. It is allelic with myosin storage myopathy, with the commonest form of familial hypertrophic cardiomyopathy, and with one form of dilated cardiomyopathy. However, the clinical picture of MPD1 is distinct from these three conditions. Objective: To collate and discuss the histological features reported in the muscle biopsies of MPD1 patients and to outline the clinical features. Results: The phenotype of MPD1 was consistent, with initial weakness of great toe/ankle dorsiflexion, and later development of weakness of finger extension and neck flexion. Age of onset was the only variable, being from birth up to the 20s, but progression was always very slow. The pathological features were variable. In this retrospective series, there were no pathognomonic diagnostic features, although atrophic type I fibres were found in half the families. Rimmed vacuoles are consistently seen in all other distal myopathies with the exception of Myoshi distal myopathy. However, they were found in a minority of patients with MPD1, and were not prominent when present. Immunohistochemical staining for slow and f ast myosin showed co-expression of slow and fast myosin in some type I fibres, possibly indicating a switch to type II status. This may be a useful aid to diagnosis. Conclusions: The pathological findings in MPD1 are variable and appear to be affected by factors such as the specific muscle biopsied, the age of the patient at biopsy, and the duration of disease manifestations.展开更多
文摘非肌性肌球蛋白重链9基因相关疾病（nonmuscle myosin heavy chain 9 related disease，MYH9-RD）是MYH9基因突变引起的遗传性血小板减少性疾病，为常染色体显性遗传。患儿自出生起即表现为巨大血小板减少症，症状常伴随终生。通常表现为轻微出血症状，但因临床对该病认识不足，患儿常被漏诊或误诊为慢性免疫性血小板减少性紫癜（ITP），给予不必要甚至有害的治疗，造成不良预后。为避免这种情况发生，本文就儿童MYH9-RD诊断治疗进展做一阐述。
文摘Background: Laing early onset distal myopathy (MPD1) is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYH7. It is allelic with myosin storage myopathy, with the commonest form of familial hypertrophic cardiomyopathy, and with one form of dilated cardiomyopathy. However, the clinical picture of MPD1 is distinct from these three conditions. Objective: To collate and discuss the histological features reported in the muscle biopsies of MPD1 patients and to outline the clinical features. Results: The phenotype of MPD1 was consistent, with initial weakness of great toe/ankle dorsiflexion, and later development of weakness of finger extension and neck flexion. Age of onset was the only variable, being from birth up to the 20s, but progression was always very slow. The pathological features were variable. In this retrospective series, there were no pathognomonic diagnostic features, although atrophic type I fibres were found in half the families. Rimmed vacuoles are consistently seen in all other distal myopathies with the exception of Myoshi distal myopathy. However, they were found in a minority of patients with MPD1, and were not prominent when present. Immunohistochemical staining for slow and f ast myosin showed co-expression of slow and fast myosin in some type I fibres, possibly indicating a switch to type II status. This may be a useful aid to diagnosis. Conclusions: The pathological findings in MPD1 are variable and appear to be affected by factors such as the specific muscle biopsied, the age of the patient at biopsy, and the duration of disease manifestations.
