A point mutation of mitochondrial genes in diabetes and deafness with focal segmental glomerular sclerosis

Abstract Deafness, diabetes and proteinuria are typically understood to be an uncommon combination. Here, we reported a 26-year-old woman with a history of persistent deafness, diabetes mellitus, and proteinuria. The diagnosis mainly depends on clinical symptoms, but the cause of the disease should be examined. The histological finding in renal biopsy showed secondary focal segmental glomerular sclerosis (FSGS), but not classic diabetic nephropathy. Further pathogeny was found. Subsequently, a 3243A>G mutation in the mitochondrial DNA was found. Thus, the diagnosis of maternally inherited deafness and diabetes (MIDD) was considered. Ineffective and unnecessary immunosuppression can be avoided through timely diagnosis. Long-term treatment of CoQ10 can be useful in MIDD patients.