Gangrenous cholecystitis is a life-threatening disease. It is characterized by necrosis of the gallbladder wall caused by ischemia followed by vascular insufficiency, and it is a risk factor for gallbladder perforation and sepsis in patients with acute cholecystitis [1]. Furthermore, acute perforated cholecystitis is associated with poor outcomes [2]. Hence, according to the Tokyo Guidelines 2018, emergency laparoscopic cholecystectomy is indicated in patients with acute cholecystitis who do not have decreased organ function and an unfavorable performance status score [3]. Early cholecystectomy has been established as the treatment of choice for acute cholecystitis and can be performed as far as 10 days after symptom onset. Early cholecystectomy is associated with a shorter hospital stay, fewer comorbidities, and greater cost-effectiveness [3, 10, 11]. However, during the COVID-19 pandemic, there was an increase in non-surgical treatment to reduce the risk of contagion exposure among medical workers based on a statement by the British Intercollegiate General Surgical Guideline on COVID-19 [12, 13]. This change was implemented because there appeared to be a risk of viral transmission through the aerosols generated by electrocautery and ultrasonic devices used in both open and laparoscopic surgery [14]. The keys to prevention of spread include proper personal protective equipment, proper transport procedures for patients with COVID-19, use of negative-pressure operating rooms, minimal staff, minimal use of electrocautery and high-energy devices, and routine use of smoke evacuation systems.

The safety of cholecystectomy for patients with COVID-19 remains unknown because of the lack of data regarding postoperative outcomes. Doglietto et al. [5] reported a higher rate of respiratory, hemorrhagic, and thrombotic postoperative complications after general anesthesia in patients with COVID-19. Furthermore, another study reviewed 34 patients with asymptomatic COVID-19 undergoing elective surgeries including major surgery. All patients developed COVID-19 pneumonia after surgery, severe complications occurred in 44.1% of the patients and mortality was 20.5% [6]. Thus, cholecystectomy for the patients with asymptomatic COVID-19 seemed to be very high risk compared to non-surgical treatment.

PTGBD has been widely performed for clinically ill patients with acute cholecystitis because of its advantages of minimal invasiveness, a low complication rate, early symptom relief, and improvements in acute inflammation [15]. However, there are some claims that delayed laparoscopic cholecystectomy after PTGBD is more likely to result in conversion to an open procedure because of the development of fibrosis, and this procedure has been associated with higher mortality, a longer hospital stay, more complications, and higher readmission rates [16,17,18]. In addition, PTGBD may be avoided in patients with gallbladder gangrene. Whereas the delayed operation group who underwent cholecystectomy after treatment including PTGBD for gangrenous cholecystitis had a longer postoperative hospital stay than the early operation group, however, there were no differences between the two groups in surgical factors and postoperative complication [19]. In our case, it corresponded to Grade II (moderate) acute cholecystitis according to the Tokyo Guidelines 2018 [3] and early laparoscopic cholecystectomy was considered to be indicated under a relatively good general condition. However, considering the risks of surgery under general anesthesia for patient with COVID-19, COVID-19 infection had to be regarded as a risk factor for surgery, although it is not included in the guidelines. Thus, PTGBD was scheduled for treatment of the patient’s gangrenous cholecystitis in the negative-pressure room with appropriate personal protective equipment, minimal stuff and minimal time if the conservative treatment resulted in an unfavorable clinical course; fortunately, however, the antibiotic therapy was remarkably effective, and PTGBD was avoided. Nevertheless, PTGBD may be a good option for treatment of gangrenous cholecystitis in patients with COVID-19.

SARS-CoV-2, the pathogen responsible for COVID-19, has a viral spike protein that binds to angiotensin-converting enzyme 2 receptors, which are present in various organs, including the gallbladder; intracellular entry of the virus then occurs [20]. COVID-19-associated cholecystitis caused by such direct vesicular involvement has been described in some case reports [21]. COVID-19 also increases the incidence of systemic endotheliitis, hypercoagulability, and thrombotic microangiopathy, which collectively contribute to the occurrence of cholecystitis [22]. COVID-19 upregulates the expression of proinflammatory cytokines such as interleukin-6 and tumor necrosis factor-alpha, triggering a cytokine storm that recruits macrophages and causes inflammatory reactions [23]. This state of hypercoagulation induced by COVID-19 can lead to gangrenous cholecystitis arising from vascular insufficiency, but this etiology was considered less likely in our case. Instead, acute calculous cholecystitis likely caused the gangrenous cholecystitis in our patient. However, it is possible that the inflammation associated with COVID-19 became a trigger for the gangrenous cholecystitis in this case.