INTRODUCTION: More than 50% of glomerular crescent formation is required for a diagnosis of crescentic glomerulonephritis in a kidney biopsy. Although treatment protocols have been established for diffuse crescentic glomerulonephritis, there is no standard treatment for patients with fewer crescents in renal biopsies. In this study the importance of crescent percentage and clinical features on renal survival independent of underlying disease was investigated. METHODS: This retrospective observational study was conducted between 2013 and 2017. Forty-nine patients with crescent formation in their kidney biopsies were evaluated. We compared clinicopathological features and renal survival. We evaluated the factors affecting the course of end stage renal disease (ESRD). RESULTS: A total of 49 patients (57% male and median age 49 years) were enrolled in this study. 39% of patients developed ESRD at follow-up. Logistic regression analysis showed that the requirement for renal replacement treatment on admission (p < 0.001), serum creatinine level above 2.7 mg/dL (p < 0.001), the presence of more than 50% glomerulosclerosis (p = 0.04) and more than 34% crescent formation (p = 0.002) were significantly associated with ESRD. Kaplan-Meier survival analysis revealed that patients with less than 34% crescent in kidney biopsy and a serum creatinine level less than 2.7 mg/dL had increased kidney survival (log-rank test p: 0.01 and p: 0.002). CONCLUSION: Patients with crescent formation in kidney biopsy more than 34% should be evaluated for more aggressive treatment modalities regardless of the underlying disease, especially if the serum creatinine level is above 2.7 mg/dL.