Clinical Features And Respiratory Function Changes In Patients With Myotonic Dystrophy Type ?

Objective:To observe the clinical characteristics and respiratory function of 15 patients with myotonic dystrophy type I(DM1),to provide more evidence for the diagnosis of DM1 and the intervention of respiratory function.Method:1.The clinical features of 15 patients with DM1 were analyzed.2.Conventional histological and enzyme histochemical stainings,including the haematoxylin Iraq red,modified Gomori trichrome,periodate Schiff reaction,oil red "O" fat staining,succinate dehydrogenase,reduced coenzyme I tetrazolium reductase,ATPase(ph4.3,4.6,10.4 and 10.6),cytochrome oxidase and nonspecific esterase staining methods were used in the diagnosis of DM1 and the pathological features were analysed of patients with DM1.3.TP-PCR method was used to analyze the CTG repeats in DMPK gene.4.15 patients with DM1 patients respiratory function,such as vital capacity,forced vital capacity,total lung capacity,forced expiratory volume in 1 second,peak expiratory flow rate,per minute maximum ventilatory volume,residual volume,carbon monoxide pulmonary diffusion function,maximum inspiratory pressure,maximal expiratory pressure were analyzed.Results:1.The initial symptom of patients with DM1 was weak hands and / or myotonia.In addition to skeletal muscle involvement was common,but also heart,endocrine system,reproductive system,eyes,nervous system.2.In the pathological changes of skeletal muscle of 15 patients with DM1,there were 13 patients with mild to severe interstitial hyperplasia and 11 patients with obvious nuclear transfer.In the HE staining and NSE staining 13 patients appeared sarcoplasmic material under the sarcolemma;In the NADH staining 8 patients showed advantage of type I muscle fiber;In the MGT staining 6 patients showed ragged red fibers;In the ATP enzyme staining showed 5 patients showed advantage oftype I muscle fiber;In the Cox staining 5 patients showed Cox negative muscle fibers.3.The CTG repeats in DMPK gene of patients With DM1 were more than 50 times,and the statistics showed that they were far higher than the normal control group(DM1 group: 124±16,normal control group:18±3,P<0.05).4.Compared to the normal control group,the abnormal respiratory function of DM1 group had a significant difference in the VC%pred,FEV1%pred,MVV%pred,FVC%pred and TLC%pred(P < 0.05),but it had not a significant difference in FEV1 /FVC and RV%pred(P > 0.05).Conclusion:Myotonic dystrophy type 1 is autosomal dominant,multisystemic diseases.Respiratory dysfunction can occur in the early stage of DM1 patients.Pulmonary function test can detect respiratory function decline in early stage,so it is necessary in the diagnosis of patients with DM1.