Objective: In recent years environmental factors were found to be contributors in etiopathogenesis of acute appendicitis. The aim of this study is to investigate the annual and seasonal distribution of acute appendicitis.

Material and Method: The records of Nigde Omer Halisdemir University Research and Training Hospital between January 2010- January 2020 were retrospectively evaluated for this observational and crosssectional study. Age, gender and pathological reports of patients that were operated with diagnosis of acute appendicitis were recorded. Patients were grouped as negative laparotomy (NL), acute appendicitis (AA), complicated appendicitis (CA) and mucosel and neoplastic lesions (MN).

Results: Out of the 3215 patients included into the study, 53,9% were men. NL rate was 17,5%. In the remaining patients, 90,6% were AA, 8,6% were CA and 0,7% were M/N. NL rate was significantly higher in women (p <0,001). The median of age was 31(IQR21) in NL, 30(IQR 19) in AA, 38(IQR29) in CA and 50,5(IQR33,5) in MN. Patients in CA and MN group were significatly older than patients in NL and AA groups (p =0,001 and p <0,001). There was no significant difference among groups according to monthly (p =0,404) and seasonal (p =0,216) distribution. The number of AA was higher while NL rates were significanlty lower in the second half of the study (p <0,001).

Conclusion: Our results demonstrate that AA increased in our institution during the last 10 years. In additon NL rates significantly decreased in the same time period. Older patients, with AA suspicion, needs further attention for the probability of CA.