A Rare Cause of Polyuria and Polydipsia in a Patient With Cystic Renal Disease: Maturity-Onset Diabetes of the Young Type 5

Hepatocyte nuclear factor-1beta (HNF-1beta) is a transcription factor that is responsible for the development of kidney, pancreas, liver and genitourinary tract. Affected individuals may present a variety of renal developmental abnormalities and/or maturity-onset diabetes of the young type 5 (MODY 5). Here we report a boy with autosomal recessive polycystic kidney disease (ARPKD) diagnosed in neonatal period who developed insulin-dependent diabetes at the age of 11. He presented with poliuria and polydipsia. The diagnosis of ARPKD was made in neonatal period based on the findings of large hyperechogenic kidneys in antenatal ultrasound and no history of renal disease in parents. Laboratory investigations revealed hyperglycemia, glycosuria, and a reduced glomerular filtration rate (GFR). Based on autoantibody-negative diabetes and low-dose insulin requirement in addition to renal anomalies, he was suspected to have MODY 5. Genetic studies identified a known heterozygous HNF1B gene mutation (S148L) compatible with an MODY 5 phenotype. As a result, MODY 5 should be considered in children with developmental kidney disease and hyperglycemia. Also HNF-1beta mutations should be suspected in patients with undefined cystic kidney disease especially when associated with other systemic findings as in our case. World J Nephrol Urol. 2016;5(3):67-70 doi: http://dx.doi.org/10.14740/wjnu272w