LEP and stage 5 chronic kidney disease: Serum leptin level is increased in patients with end stage renal failure secondary to chronic inflammation, decreased glomerular filtration rate and increased insulin resistance.9 In a study by M.P. Fontan et al, higher serum leptin levels in peritoneal dialysis (PD) patients was compared to hemodialysis and predialysis stage 5 CKD patients.10 In our study we aimed to investigate the effect of varying concentrations of recombinant human leptin hormone on platelet aggregation in PD patients.