Mitochondrial Diabetes Mellitus With 3 Cases

Objective: With the developing study of the gene genetics of diabetes mellitus,mitochondrial diabetes mellitus, as a specific type of diabetes that was frequently reported in these years,is more and more recognised. Mitochondrial tRNA^Leu(UUR)3243A→G mutation is the most common causative agent.An early-diagnosis and treatment can effectively delay the development of this disease.But,its phenotypes are more likely with type-1-diabetes and type-2-diabetes.So,it's easily to get a wrong diagnosis and incorrect treatment,those will accelerate the development of this disease. In this paper,we disscussed cases of diabetes caused by mitochondrial tRNA Leu(UUR)3243A→G mutation,to give a further recognition on the pathogenesis of this disease,to master its clinical feature,and to discuss its treatment.As a result,we could have a high rate on the clinical diagnosis,so the patients could be directly treated as early as possible.And their other family members will be rewarmed to prevent from this diase.All the family members will have a better quality of life.Methods: We have 3 cases of mitochondrial diabetes mellitus which was finally diagnosised by gene detection or pathology of muscle biopsy in endocrine secretion of our hospital.In this paper ,we will describe the development of disease and the process of our diagnosis and treatment in full,to analyze their clinical phaenotype,auxiliary examination especially genetic or pathological witness of diagnosis,we will include the clinical features,estimated the therapeutic efficacy of mitochondrial diabetes mellitus. At the same time we will refer to the pertinent literature that have reported mitochondrial diabetes mellitus after 1992 internal and outternal.By combining the clinical cases and the literature ,we will analyze and conclude and describe the pathogenesis,clinical phenotypes,the evidence of diagnosis and the therapeutic principle of mitochondrial diabetes mellitus in this paper.Also,we willreasonally extrap its prospect of diagnosis and treatment.Results: Mitochondrial diabetes mellitus is caused by mutation in DNA which lead to disorder of the mitochondrial oxidative phosphorylation ,then make a deficient of enegy.In beta-cells the disorder inhibit the paralyse of ATP-dependent potassius channels and depolarization of memb-electric potential.Then the patency of voltage-dependent calcium channel would be disturbed,calcium influx is decreased,and insulin secretion cupled with calcium balance is inhibited.At the same time,the disorder derange redox state and oxygen-derived free radicals are increased whih lead to proceeding death of beta-cell.Inskeletal muscle,the disorder makes anaerobic glycolysis potencialization.So the lactification incrrease,the glyconeogenesis accentuate and the level of serum glucose goes up.Its clinical manifestion are heterogeneitied. The clinical features are concluded as follows:a thin somatotype, an early onset,matenal inheritance, with nerve deafness, progre- ssive retrogression of beta cell's function and with other symptoms.Its final diagnosis depend on gene detection, muscle biopsy could also provide evidence of diagnosis, and now,gene detection with RCR is admoved in clinic.To therapy this disease,insulin is suggested an early use,aggravating activities and drugs of bigunides should be avoide.At the same time, coenz- ymeQ10 is a better choice.Conclusion: As a specific type of diabetes,mitochondrial diabetes mellitus has its specificity on its pathogenesy ,clinical manifestation and treatment.Clinical missed diagnosis and misdiagnosis will easily result in a rapide and nonreversible progression.We should deepen our recognicion of mitochondrial diabetes mellitus.An early and correct diagnosise and effective therapy are better for direction therapy for patients and estimating the risk for other member in their family.So doctors could adopt comprehesive precaution to defer its morbidity. Rapid expansion of molecular biology and high investigation of gene will bring us more hopingand confidence of diagnosis and treatment of this disease.