Endocrine Abstracts

Background: Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes due to defects in mitochondrial DNA (mtDNA). Maternal transmission of diabetes and neurosensorial deafness are the main clinical features of MIDD followed by other mitochondrial disorders, myopathies, and macular dystrophy. 3243 A>G is the mutation most frequently associated with this condition, but also other mtDNA variants have been linked with MIDD. We describe the case presenting with hyperglycemia and hair findings diagnosed as MIDD.

Case report: A 9-year-old boy was referred to our clinic for hyperglycemia. He was the third child of consanguineous healthy parents. He had previously diagnosed bilateral neurosensorial deafness and he was wearing a conventional hearing aid. His weight was 24 kg (3–10.p), height 132 cm (50.p), and BMI 13.8 kg/m². He had kinky, sparse, and ivory hairs. Fundus examination was normal, maculopathy was not detected. There was no hepatomegaly or splenomegaly. On laboratory; his glycated hemoglobin (HbA1c) was 6.6%, hemogram, thyroid, hepatic and renal function tests were normal. Celiac and diabetes-related (islet cell antibody, anti-glutamate decarboxylase, insulin auto antibody) antibodies were negative. Serum copper and zinc levels were normal. Electromyogram was normal. The whole mtDNA analysis was revealed TRNL1 gene the mutation.

Conclusions: Determination of the mitochondrial origin of diabetes is important for genetic counseling and clinical care. The whole mtDNA should be screened because the 3243A>G variant is not as frequent in children as in adults for MIDD our patient’s hair features was suspected Menkes Kinky hair disease and zinc deficiency. The brittle, tangled, sparse, steely or kinky hairs that are often white, ivory, or gray in color with easy pluckability are main findings for Menkes Kinky hair disease is an X-linked recessive trait caused by mutations in the ATP7A gene leading to disturbed copper metabolism. However, our patient’s serum copper and zinc levels were normal.