Aim. To study the dynamics of cystatin C in patients after procedures on retroperitoneal viscera using laparoscopic and retroperitoneal access.
Material and methods. A prospective study of serum and urine cystostatin C levels in 162 patients with renal cysts using laparoscopic (n=83) and retroperitoneal access (n=79) was carried out. Patients were divided into four groups depending on the duration of the procedure and the gas level. For determination of cystatin C level in serum and urine, flow cytometry was performed using Human Kidney Function Panel 2 Mix and Match Subpanel (for Serum/Plasma Samples).
Results. A significant increase in the serum and urine level of cystatin C in groups 3 and 4 was seen on the 1st day after laparoscopic procedures in case of pneumoperitoneum pressure above 12 mm Hg., regardless of its duration. For retroperitoneoscopic procedures, similar changes were found only in group 4 with a gas pressure above 12 mm Hg and duration of the intervention of more than 30 minutes. By day 3, cystatin C levels returned to baseline values in all groups.
Conclusion. The most significant risk factor for acute kidney injury after laparoscopic and retroperitoneoscopic procedures is the gas pressure. The second most important factor is the duration of the intervention. Pneumoperitoneum has a greater effect on cystatin C levels compared to retropneumoperitoneum.

Keywords: retropneumoperitoneum, pneumoperitoneum, cystatin C, acute kidney injury