Possibilities of colon ultrasound in determining the severe course and prognosis of recurrent Clostridioides difficile colitis

Purpose of the study : to determine ultrasound signs of severe course and prognostic criteria for recurrence of Clostridioides difficile ( Cl. difficile ) colitis and the possibility of separating clinically negligible antibiotic-associated diarrhea from its case related with Clostridial infection. In order to fulfill the aim the study involved patients with and without COVID-19. Material and Methods . A continuous random sample consisted of 253 patients with antibiotic-associated diarrhea. We used standard, recommended by international and Russian agreements methods of the intestinal wall ultrasound examination and diagnostics of SARS-CoV-2 and Cl. difficile infection. Results . It was found that in antibiotic-associated diarrhea widespread intestinal wall thickening greater than 3.2 mm by ultrasonography is observed in Cl. difficile colitis. In case of diarrhea in patients with COVID-19, the detection of intestinal wall thickness of more than 4.0 mm indicates the presence of pseudomembranous colitis when intestinal pathology of ischemic genesis is excluded. Severe course of Сlostridial colitis is characterized by widespread increase in the colonic wall thickness with a maximum value of more than 7.2 mm at echography. Furthermore, there may be additional ultrasound signs of severe course of Cl. difficile colitis: the presence of paracolic free fluid and/or ascitic fluid in various regions of the abdominal cavity; increased echogenicity of adipose tissue adjacent to the inflamed intestine (omentum) and “increase” in its volume; impaired stratification of the colonic wall; thickening of the small intestine wall more than 3.0 mm; paresis of the colon; toxic megacolon. When thickening of the intestinal wall detected by ultrasound in patients with Cl. difficile colitis is more than 6.0 mm after the standard course of treatment with the achievement of clinical target results (absence of diarrhea, normalization of temperature and laboratory parameters) it is a predictor of recurrence of the disease. The described ultrasound diagnostic criteria for pseudomembranous colitis can be used for establishing its severe course and high probability of recurrence in the case of the combination of Cl. difficile colitis with COVID-19. Conclusion : the use of ultrasound examination of the intestinal wall and surrounding structures allows to detail the diagnosis of Cl. difficile colitis.