New-Onset Diabetes after Kidney Transplantation: Diagnosis, Risk Factors, and Management

New-onset diabetes after transplantation (NODAT) is a frequent and severe complication after renal transplantation. It is diagnosed according to standard criteria for type 2 diabetes. Risk factors for NODAT are non-modifiable (non-white ethnicity, older age, genetic predisposition, previous glucose intolerance, steroid therapy, male donor, and others) and modifiable (obesity, viral infections, and immunosuppressive therapy). Glucose control is needed immediately after renal transplantation and after 3, 6, and 12 months and annual glucose control is needed after that period. When NODAT is diagnosed, the primary goal includes lifestyle modification, like a diet with weight loss and exercise, and obtaining optimal glucose control to reduce micro- and macrovascular complications of diabetes. In order to obtain better glucose control, modification of immunosuppressant therapy is also needed, like a reduction of corticosteroid and calcineurin inhibitors and also a conversion of tacrolimus to a less glucotoxic agent. Pharmacotherapy includes oral hypoglycemic agents (in most cases metformin, sulfonylureas, and dipeptidyl peptidase-4 (DPP-4) inhibitors) and insulin (in most cases biphasic insulin several times daily or intensive insulin therapy). Finally, metabolic risk factors like dyslipidemia and hypertension should also be treated, and a regular annual screening should be performed for micro- and macrovascular complications of diabetes.