How prevalent is hydronephrosis secondary to acute appendicitis: A cross-sectional study

Background: Right hydronephrosis secondary to acute appendicitis is an under-reported phenomenon with only several case reports published. Objectives: To assess the incidence of this phenomenon in our database of patients diagnosed with acute appendicitis. Methods: Data were collected on 1092 patients who underwent surgery due to acute appendicitis between 2003 and 2007 in our tertiary medical center. The data entailed demographic, surgical, and hospitalization parameters including ultrasound or computed tomography examinations and presence of right hydronephrosis prior to surgery. Results: Out of 1092 patients, appendicitis was eventually diagnosed in 87.4% of the patients. Only 594 (54%) had preoperative imaging performed prior to surgery (ultrasound or computed tomography). Out of these 594 patients, 21 (3.5%) had a new right hydronephrosis diagnosed and all had appendicitis with 15/21 (71%) having a retrocecal appendix. Of those with retrocecal appendix, 10 were pregnant women (48%). Erythrocyturia was present in 15/21 patients (71%) and in 10/11 of patients (91%) after excluding those who were pregnant. No significant differences were seen in patients with hydronephrosis regarding age, hospitalization, and surgery time. In all patients, an ultrasound was performed 2 weeks after surgery demonstrating the disappearance of hydronephrosis. Median follow-up time was 41.7 months (range 14.8–118.4 months). Conclusions: Our study shows that 3.5% of our cohort had right hydronephrosis secondary to acute appendicitis. Although this presentation is very rare, physicians should be aware of this phenomenon and the risk for delayed diagnosis and treatment of acute appendicitis.