Microbiome of the Initial Small Intestine in Patients With Severe Acute Pancreatitis: a Pilot Study

Disruption of intestinal homeostasis is a leading factor in the pathogenesis and progression of systemic inflammation in patients with acute severe pancreatitis. The development of systemic complications occurs due to both mesenteric hypoperfusion and dysregulation of intestinal motility, as well as destruction of the intestinal barrier, with translocation of bacterial bodies and their substrates. This increases the risk of developing multiple organ failure and increased mortality. With the advent of high-throughput sequencing methods for microbiome samples, for example, in the 16S rRNA format, the possibilities for studying the structure of microbial communities have expanded significantly. In this regard, there is increasing evidence of the relationship between human health and the microflora inhabiting various parts of the body. AIM OF THE STUDY . Description of the microbiota composition of the initial sections of the small intestine in patients with severe acute pancreatitis. MATERIAL AND METHODS . The study included 7 patients with a diagnosis of severe acute pancreatitis (6 men, 1 woman), the average age was 54.1±14.4 years. Patients were divided into two groups. Group 1 (n=4) included patients admitted on the 2nd–4th day from the onset of a pain attack. Group 2 (n=3) included patients admitted no later than 24 hours from the onset of the disease. The bacterial composition of jejunal swab samples was studied using 16S RNA sequencing. The severity of the condition was assessed using the integral APACHE II, SOFA, SAPS II scales. In patients of the main group, APACHE II was score 22±2.83, SOFA was score 6.8±0.5, SAPS II was score 32.9±6.4, in patients of the comparison group, APACHE II was score 18.0±3.7, SOFA was score 4.0±2.6, SAPS II was score 24.4±5.0. The material was collected at the time of insertion of a sterile multifunctional intestinal catheter behind the Treitz ligament, no later than 6 hours after admission to the intensive care unit. At the time of material collection, the patients did not receive antibacterial therapy or enteral nutrition. RESULTS . More severe disease was associated with reduced representation of Nesseria species in the microbiome mucosa and parvimonas micra, inhabiting the mucosal layer, as well as Megasphaera micronuciformis. The proportion of the genera Streptococcus (species S. rubneri / parasanguinis / australis) and Actinomyces and a number of genera from the Enterobacteriaceae family in such patients was, on the contrary, higher.