Maturity Onset Diabetes of the Young in a Saudi Child: Case Report and Review of the Literature

Abstract

Maturity onset diabetes of the young (MODY) is an autosomal dominant subtype of non-insulin-dependent diabetes mellitus that occurs at a young age. The patient may be asymptomatic, but if he is symptomatic, it usually takes the form of hyperglycemia with no ketosis. We describe a child whose history, physical findings, and results of investigations are consistent with the diagnosis of MODY. To the best of our knowledge, MODY has never been reported in the Saudi Arabian population. Case ReportA 10-year-old boy presented to the pediatric clinic with a history of nocturnal enuresis of six months' duration. The family first noticed that the child, who had previously been completely dry for the night, started to wet his bed almost every night. They thought it was due to the cold weather, as it started during winter time, but the symptoms persisted. He admitted that his drinking and voiding habits had increased slightly over the same period. His appetite and weight did not change. In the clinic he was found to have hyperglycemia (random blood sugar, 23.9 mmol/L; fasting blood sugar, 12.6 mmol/L). He was not dehydrated or acidotic. His urine, which was 4+ for sugar, was negative for ketones, so he was admitted for further investigation and management. He gave no history of infections especially immediately prior to the beginning of his symptoms. Other than tonsillectomy at the age of five years, past history was normal.Family history was very important, in that both parents are first-degree cousins and both are diabetics. The diabetes in his father, who was 55-years-old, had been diagnosed four years earlier, and he was on oral hypoglycemics. His mother, who was 48-years-old, had been diagnosed as having NIDDM when she was 35-yearsold. She had been on oral hypoglycemic agents for eight years, but changed to insulin five years ago. NIDDM had been diagnosed in his 30-year-old, eldest brother when he was 28 years old, and he had been on oral hypoglycemic agents since then. None of the remaining seven older siblings had any symptoms suggestive of diabetes, but unfortunately, they all refused to be screened. NIDDM was also found in his maternal grandparents, but the age of onset of their diabetes was not certain. His maternal grandmother, who had used oral hypoglycemic agents, had been on insulin for the last few years. His grandfather had died a few years earlier, but the cause of death was not known. On his father's side, only his father's cousin was diabetic and treated with oral agents.Examination revealed a normal-looking obese boy who was in no distress. He weighed 59.4 kg (> 95%) and was 149 cm tall (95%). His vital signs were normal; in particular, he was not tachypneic and there was no acetone odor to his breath. Remaining findings from general examination were essentially normal. During his hospitalization, his hyperglycemia was confirmed repeatedly, but urine remained ketone-free. His complete blood count, blood gas values, serum electrolyte concentrations, and lipid profile were within normal limits. His T3, T4,...