Ruveena is dual training in Endocrinology and General Medicine. Very fortunate to have worked in various parts of our beautiful Te Ika a Maui (North Island), including Whanganui, Rotorua, and more recently Auckland
End Stage Renal Disease and Diabetes:
Is It All 'Diabetic Nephrophy'?
Ms D is a lean, 58 year-old with type 2 diabetes (T2D), who had been on haemodialysis for two years. Her renal failure had been attributed to diabetic nephropathy.
Four members of Ms D’s family, spanning two generations, had been diagnosed with T2D and “diabetic nephropathy” between the ages of 37-46. Glycaemic control had been relatively easy to achieve, with HbA1c of 37-52 mmol/mol on either no treatment, a sulphonylurea, or low dose insulin. Macroalbuminuria was present at the time of diabetes diagnosis (urine albumin:creatinine ratios 104-218; normal <3g/mol). The eGFR in two family members was below the 10th centile at time of diabetes diagnosis. Other diabetes-associated microvascular complications are noticeably absent- none had diabetic retinopathy. The renal disease was progressive, reaching end stage 13-18 years after the diagnosis of diabetes. Renal imaging late in the course of the disease showed cystic changes and, in two subjects, probable renal cell carcinoma. One had the tumour excised: histological findings of non-tumorous tissue demonstrated acquired cystic disease and focal segmental glomerulosclerosis, with no diabetic nephropathy. There was also a strong family history of early onset polyarticular gout.
Clinical guidelines for Diabetes and Chronic Kidney Disease (CKD) advise consideration of an alternate aetiology of CKD, if diabetic retinopathy is absent. The family pedigree raised suspicion of an autosomal dominantly-inherited syndrome. We considered MODY5 (renal cysts and diabetes syndrome), but no mutation or deletion in HNF1B was found. An alternate cause of this familial nephropathy with diabetes is being explored, using a gene panel for inherited cystic and glomerular kidney disease, and the results will be presented.
Clinical Practise Point:
Not all renal failure in patients with diabetes can be explained by diabetes alone. Non-diabetic renal disease should be considered in the differential diagnosis, as there is potential for alternative management.