Impact of the COVID-19 pandemic on appendicitis treatment in Germany-a population-based analysis

Abstract
Purpose Acute appendicitis is one of the most common reasons for emergency medical consultation. While simple appendicitis can be treated with antibiotics or surgery, complex appendicitis including gangrene, abscess, and perforation requires appendectomy. During the COVID-19 pandemic in early 2020, an overall drop in emergency room consultations was observed. We therefore aimed to investigate the incidence and treatment strategies of acute appendicitis during that period. Methods Data of insurance holders with the ICD code for "acute appendicitis" or OPS procedure of appendectomy of a major health insurance company in Germany were analyzed retrospectively. Groups were built, containing of the means of March-June of 2017, 2018, and 2019, defined as "pre-COVID group" with the "COVID group," defined as data from March to June of 2020. Data was analyzed by age, sex, comorbidities, length of hospital stay, diagnoses, and treatment. Data of the COVID group was analyzed for simultaneous COVID-19 infection. Results During the COVID-19 pandemic of early 2020, an overall reduction by 12.9% of patients presenting with acute appendicitis was noticeable. These results were mainly due to decreased rates of uncomplicated appendicitis, while complicated appendicitis was scarcely affected. Especially in the group of females < 40 years, a drastic reduction was visible. Rates of extended surgery did not change. Likewise, the complication rate like appendix stump leakage or need for re-operation did not differ. In March 2020, 4.8% of acute appendicitis patients had concomitant COVID-19 infection. Conclusion In line with the overall drop of emergency room visits during the COVID-19 pandemic of spring 2020 in Germany, a significantly lowered number of patients with uncomplicated appendicitis were noticeable, whereas complicated appendicitis did not differ. Also, treatment and complication rate of acute appendicitis did not change. These findings might be a hint that acute appendicitis is not a progressing disease but caused by different entities for uncomplicated and complicated appendicitis and therefore another clue that uncomplicated appendicitis can be treated with antibiotics or observation. Nevertheless provided data does not cover outpatient treatment; therefore, no statement observation or antibiotics in outpatients can be made.