Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, outcomes and management of many diseases have been affected. Acute appendicitis is a common acute abdomen. The incidence rate is 0.05%-0.5%. Studies reported that the number of patients with appendicitis admitted to emergency department significantly decreased since the pandemic. People avoided going to the hospital for fear of being infected. Different countries have different epidemic prevention measures that result in different treatment outcomes. The Chinese government also published some temporary measures in order to prevent the outbreak.

To explore the changes in management and outcomes of acute appendicitis during the COVID-19 pandemic in the North of Beijing.

Patients with acute appendicitis admitted to Beijing Tsinghua Changgung Hospital between February and June 2019 and February and June 2020 were retrospectively reviewed. Cases were grouped according to admission year. The demographic characteristics, present illnesses, medical history, symptoms and signs, comorbidities, blood test results, imaging data, appendix pathology, and treatment details were compared.

Overall, 74 patients received nonsurgical treatment and 113 patients underwent surgical treatment in group 2019, whereas 159 patients received nonsurgical treatment and 26 patients received surgical treatment in group 2020. Fever, thick appendix, nonsurgical management, and uncomplicated appendicitis (simple or supportive appendicitis) were more common in group 2020 (P < 0.05). Among the nonsurgical management cases, the neutrophil percentage, neutrophil-to-lymphocyte ratio, and recurrence rate were higher in group 2020 (P < 0.05). Among surgically managed cases, there were more cases with gastrointestinal symptoms, peritonitis, ascites in the image, and intraoperative adhesion or ascites in group 2020 (P < 0.05). The white blood cell count, time from diagnosis to surgery, surgical time, and intraoperative blood loss were higher in group 2020 (P < 0.05).

During the COVID-19 pandemic, patients suffering from acute appendicitis in Beijing tended to present with severe symptoms and opt for nonsurgical treatment. For patients who underwent surgical management, the operation was delayed and more difficult during the pandemic. Nevertheless, the hospital stay and the incidence of postsurgical complications did not change.

The World Health Organization declared a global coronavirus disease 2019 (COVID-19) pandemic on March, 2020. Then, the number of infected patients significantly increased. Currently, over 100 million patients have been infected worldwide. The first COVID-19 case in Beijing was confirmed in January, after which the pandemic reached its peak by the end of June 2020, with 922 confirmed cases.

Since the outbreak of the COVID-19 pandemic, the outcomes and management of many diseases have been affected. Acute appendicitis is a common acute abdomen. The incidence rate is 0.05%-0.5%[1,2]. A study conducted in Italy reported that the number of patients with appendicitis admitted to the emergency department (ER) has significantly decreased since the pandemic[3]. Another study conducted in Israel showed that weekly admissions decreased by 40.7%[4]. People were avoiding going to the hospital for fear of being infected. Consequently, the United Kingdom published new guidelines and changed the management of acute appendicitis[5]. The Chinese government also published several temporary measures to prevent the outbreak. All patients requiring admission were asked to perform blood tests for complete blood count (CBC), immunoglobulin (Ig) G, and IgM antibody. Chest computed tomography (CT) and swabs were also ordered.

Different countries have different epidemic prevention measures that result in different treatment outcomes. The aim of this research was to explore whether the COVID-19 pandemic changed the management and outcomes of acute appendicitis in Beijing.

Beijing Tsinghua Changgung Hospital is one of the only two large hospitals in the northern part of Beijing, serving 700000 residents. Accordingly, our data represent the real-life situation in northern Beijing. Our study suggested that patients with acute appendicitis presented with more severe conditions at admission during the pandemic, and they preferred nonsurgical management. For patients who underwent surgical management, the operation was delayed and was more difficult during the pandemic. However, the hospital stay and the incidence of postsurgical complications did not change.

In the present study, the number of admitted patients did not decrease, which was inconsistent with previous studies[3,4]. Nevertheless, we found that the proportion of uncomplicated appendicitis was lower than that in the same period the previous year (52.4% vs 64.2%), which suggested that the morbidity of acute appendicitis did not change. A previous study reported that the appendix was thicker and that the inflammation around the appendix was more severe during the pandemic based on CT scans[6], which is consistent with our study results (9.31 ± 4.05 mm vs 4.78 ± 4.20 mm, P < 0.01). These findings suggested that patients feared becoming infected while in the hospital and that they preferred to stay at home until their symptoms became too serious to manage at home.

The 2020 WSES guidelines for acute appendicitis recommend that nonsurgical treatment should be the first choice for uncomplicated appendicitis[7], while surgery should be the first choice for complicated appendicitis (gangrene or perforated appendicitis). As patients did not want to spend a long time in the hospital because of the fear of becoming infected during the pandemic, many selected nonsurgical treatment[8]. Some doctors in other countries selected nonsurgical management for most patients with acute appendicitis because they could not determine whether the patient was infected with COVID-19 before treatment[9]. A previous study showed that 74% of surgeons modified their practice to predominantly nonsurgical management, while 61% of patients selected nonsurgical management to decrease their time spent in the hospital[10]. A global survey also suggested that doctors preferred nonoperative management during the pandemic[11]. This study found that, after the pandemic, the proportion of nonsurgically managed cases of appendicitis in our hospital increased from 39.6% the previous year to 85.9%, which is consistent with the situation abroad. Further research on the outcome of nonsurgical treatment with complicated appendicitis should be performed in the future.

The NLR has been widely used to evaluate various malignant tumors as an indicator of immune status[12,13]. NLR has also been used as an indicator for the diagnosis and severity evaluation of acute appendicitis. Previous studies reported that the NLR could be used as an important parameter in the diagnosis of appendicitis[14,15], while there was also a substantial correlation between the NLR and disease severity. This study demonstrated that patients who selected nonsurgical management during the pandemic presented with higher N% and NLR. We also detected some severe patients whose condition was more appropriate for surgical management but who underwent nonsurgical management during the nonpandemic period. This was consistent with the increased proportion of nonsurgical management during the pandemic observed in the present study. Nevertheless, there was no significant difference in the rates of conversion to surgery between groups, which indicated that the outcomes of IV antibiotic treatment were the same as those during the nonpandemic period.

Recurrence is an important problem of nonsurgical management. The APPAC study reported that the 1-year, 3-year, and 5-year recurrence rates of nonsurgical treatment were 27.3%, 35.2%, and 39.1%, respectively[16]. Our findings demonstrated a significant decrease in recurrence during the pandemic (1.3% vs 21.6%); however, bias was possible due to the short follow-up in group 2020.

Among surgically managed cases, our study demonstrated that patients presented with more gastrointestinal symptoms (80.8% vs 58.4%) and more severe physical signs during the pandemic period, especially peritonitis (96.2% vs 67.3%). Peritonitis emerges when periappendiceal exudation stimulates the parietal peritoneum, thus representing severe abdominal infection. Patients also presented with higher WBCs (14.92 ± 4.39 vs 13.22 ± 3.72), which was consistent with a previous study[8]. A global survey revealed that 56.1% of the study cases had more severe septic abdominal diseases during the pandemic, especially appendicitis and cholecystitis (41.8% and 40.2% of the study cases, respectively)[17].

To prevent COVID-19 infection among medical teams, the Chinese government ordered all patients to take a blood test for CBC, IgG, and IgM antibodies; chest CT; and swabs before admission. Although some foreign countries increased the CT scan rates[18], they did not require every patient to undergo all the tests before admission[19]. It took nearly 12 h to obtain the results of all of these tests and examinations in our hospital, which was why patients experienced a longer time from diagnosis to operation during the pandemic. A longer waiting time might lead to more severe ischemia of the appendix wall and an increased possibility of gangrene or perforation. A previous study reported that a time from onset to operation > 48 h, the rate of perforated appendicitis was 3.58 times that within 24 h[20]. Severe infection can lead to more severe intraoperative abdominal adhesions and ascites, thus increasing the difficulty of operation, prolonging the surgical time, and increasing the intraoperative blood loss, all of which were found in the present study. Some doctors are concerned that pneumoperitoneum may leak virus-contaminated gas from the trocar during laparoscopic surgery[5], while others are worried that electronic devices might aerosolize COVID-19, although there is no evidence for this. British guidelines recommended open surgery as the predominant procedure for acute appendicitis. The proportion of open surgeries significantly increased in the United Kingdom[19]. For the same reason, Italian doctors prefer open appendectomy without electronic devices[21]. However, the 2020 WSES guidelines recommended laparoscopic appendectomy as the first choice for complicated appendicitis[7]. Laparoscopic surgery leads to a shorter hospital stay and a lower rate of wound infection. In our study, laparoscopic appendectomy was the only operation used for surgical management of these patients. As all patients underwent a blood test for CBC, IgG and IgM antibodies and swabs before admission, the medical team did not perform the operation until negative results were obtained, thus putting at ease the medical team who did not have to worry about the possibility of COVID-19 infection during the operation. Some countries have used smoke evacuation systems with filters to evacuate surgical smoke during laparoscopic appendectomy[11], which will increase the ratio of minimally invasive surgery and bring the best benefits to patients.

According to a previous study, the incidence of postoperative complications during the pandemic was twice as high as that before the pandemic[22]. The authors suggested that the increased severity of appendicitis might be caused by a fear of admission. There was no significant difference in postoperative complication rates between groups in the present study, which might be related to a lower number of operation cases and short follow-up time during the pandemic or indirectly related to the proper government orders.

This study has several limitations. As this was a retrospective study, it was inevitably biased. This was a single-center study with a small sample size. The follow-up time during the pandemic was short. Therefore, the results need to be further confirmed by large case studies.

In summary, the proportion of cases using nonsurgical management for appendicitis in northern Beijing increased during the COVID-19 pandemic. The patients presented with more serious conditions. To prevent COVID-19 infection, a more complex preoperative test and examination were adopted, which resulted in a longer preoperative waiting time and surgical time. Intraoperative blood loss increased. However, the complex preoperative examination was useful, as it screened the patients in need of laparoscopic appendectomy, ensured better postoperative outcomes, and did not significantly increase the postoperative complication rate.

During the COVID-19 pandemic, patients suffering from acute appendicitis in Beijing tended to present with severe symptoms and opt for non-surgical treatment. For patients who underwent surgical management, the operation was delayed and more difficult during the pandemic. The hospital stay and the incidence of post-surgical complications did not change. The complex preoperative examination can ensure the safety of laparoscopic appendectomy, which leads to a better postoperative outcomes.