Is conservative management safe in patients with acute ureterolithiasis and perirenal stranding?

In patients presenting with ureterolithiasis, perirenal stranding is frequently observed in non-contrast computed tomography. Because perirenal stranding may be caused by tears in the collecting system, previous studies have described an increased risk of infectious complications and suggested broad empiric antibiotic therapy and immediate decompressing of the upper urinary tract. We hypothesized that these patients can also be managed conservatively. Therefore, we retrospectively identified patients with ureterolithiasis and perirenal stranding and compared diagnostic and treatment characteristics as well as treatment outcomes between patients undergoing conservative versus interventional management by ureteral stenting, percutaneous drainage or primary ureteroscopic stone removal. We classified perirenal stranding as mild, moderate or severe based on its radiological extent. Of 211 patients, 98 were managed conservatively. Patients in the interventional group had larger ureteral stones, more proximal ureteral stone location, more severe perirenal stranding, higher systemic and urinary infectious parameters, higher creatinine levels, and received more frequent antibiotic therapy. The conservatively managed group experienced a spontaneous stone passage rate of 77%, while 23% required delayed intervention. In the interventional and conservative groups, 4% and 2% of patients, respectively, developed sepsis. None of the patients in either group developed a perirenal abscess. Comparison of perirenal stranding grade between mild, moderate and severe in the conservatively treated group showed no difference in the spontaneous stone passage and infectious complications. In conclusion, conservative management without prophylactic antibiotics for ureterolithiasis and perirenal stranding is a valid treatment option as long as no clinical or laboratory signs of renal failure or infections are observed.