BACKGROUND: Transplantation is the best and approved method of renal replacement therapy. Graft function depends not only on proper regulation of immune processes but also on the optimal control of chronic diseases. The obesity epidemic involves the healthy population and organ recipients equally. Obesity and metabolic syndrome lead to a number of disorders exerting adverse effects on the transplanted organ.

CASE REPORT: We report a case of a kidney recipient, 12 years after transplantation, with chronic graft failure (serum creatinine level 2.1 mg/dl, GFR 31 ml/min/1.73 m2), morbid obesity (weight 139.8 kg, BMI 46.2 kg/m2, excess body mass 73.1 kg), hypertension, poorly controlled type 1 diabetes (HbA1c 8.8%), and ischemic heart disease. The cause of chronic kidney disease was diabetic nephropathy. The patient was the first Polish kidney recipient referred for bariatric gastric bypass surgery (GB). Directly after surgery, transient creatinine elevation (4.7 mg/dl) was noted. There was no reduction in diuresis. Desired weight loss was achieved within 12 months after surgery (body mass 81.9, BMI 27.1 kg/m2, percentage loss of excess weight 86.9%) with improved graft function (serum creatinine level 1.3 mg/dl, GFR 45.1 ml/min/1.73 m2) and reduction of daily insulin requirement from 74 to 40 units. The severity of hypertension and ischemic heart disease diminished as well.

CONCLUSIONS: Metabolic surgery is the best treatment of obesity and may contribute to post-transplantation care if weight gain is observed, as a result of the interaction of many factors leading to deterioration of renal graft function.

Keywords: Bariatric Surgery, Kidney Transplantation, Metabolic Syndrome X