Postinfectious irritable bowel syndrome in children

Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders in adults, children, and adolescents. This paper reviews the etiology and pathogenesis of IBS, particularly one of its subtypes, postinfectious IBS, associated with a prior acute intestinal infection. The authors discuss risk factors, diagnosis, and treatment for postinfectious IBS and describe diagnostic search and therapeutic algorithm in a child. Treatment for IBS involves changes in diet and lifestyle, pharmacotherapy, and psychotherapy. This case report is interesting for clinicians since only attempts are made to systematize guidelines on the diagnosis and treatment for postinfectious IBS. However, specific management strategies for this condition are scarce, making the diagnosis difficult and resulting in treatment delay. KEYWORDS: irritable bowel syndrome, functional gastrointestinal disorders, prokinetic agent, synbiotic, Maxilac. FOR CITATION: Pechkurov D.V., Tyazheva A.A. Postinfectious irritable bowel syndrome in children. Russian Journal of Woman and Child Health. 2021;4(3):292–297 (in Russ.). DOI: 10.32364/2618-8430-2021-4-3-292-297.

Electroacupuncture Relieves Visceral Hypersensitivity by Inactivating Protease-Activated Receptor 2 in a Rat Model of Postinfectious Irritable Bowel Syndrome

Background. The role of protease-activated receptor 2 (PAR2) in the analgesic effect of electroacupuncture (EA) on visceral hypersensitivity (VH) in postinfectious irritable bowel syndrome (PI-IBS) has yet to be elucidated. Aim. In this study, we investigated the molecular mechanisms underlying the analgesic effect of EA in a rat model of PI-IBS. Methods. Visceral hypersensitivity was evaluated by the abdominal withdrawal reflex test before and after administration of the PAR2 agonist, PAR2-AP, and/or EA. The protein expression and mRNA levels of PAR2, CGRP, SP, and TPSP in colon tissues were measured by immunofluorescence, western blot, and RT-PCR. Results. We found that EA could alleviate VH and significantly decrease protein and mRNA levels of PAR2, TPSP, CGRP, and SP in PI-IBS rats. The analgesic effect of EA on VH was slightly reduced in the presence of PAR2-AP. Conclusions. These results suggest that EA alleviates VH symptoms through downregulation of the levels of the TPSP/PAR2/SP/CGRP signaling axis in colon tissues in PI-IBS rats. Together, our data suggests that PAR2 plays a critical role in the analgesic effect of EA on VH in PI-IBS.

The Effect of Tong-Xie-Yao-Fang on Intestinal Mucosal Mast Cells in Postinfectious Irritable Bowel Syndrome Rats

Objective. To investigate the effects of Tong-Xie-Yao-Fang (TXYF) on intestinal mucosal mast cells in rats with postinfectious irritable bowel syndrome (PI-IBS).Design. PI-IBS rat models were established using a multistimulation paradigm. Then, rats were treated with TXYF intragastrically at doses of 2.5, 5.0, and 10.0 g·kg−1·d−1for 14 days, respectively. Intestinal sensitivity was assessed based on abdominal withdrawal reflex (AWR) scores and fecal water content (FWC). Mast cell counts and the immunofluorescence of tryptase and c-Fos in intestinal mucosa were measured; and serum IL-1β, TNF-α, and histamine levels were determined.Results. AWR reactivity and FWC which were significantly increased could be observed in PI-IBS rats. Remarkably increased mast cell activation ratio in intestinal mucosa, together with increased serum TNF-αand histamine levels, could also be seen in PI-IBS rats; furthermore, PI-IBS-induced changes in mast cell activation and level of serum TNF-αand histamine could be reversed by TXYF treatment. Meanwhile, tryptase and c-Fos expression were also downregulated.Conclusion. TXYF improves PI-IBS symptoms by alleviating behavioral hyperalgesia and antidiarrhea, the underlying mechanism of which involves the inhibitory effects of TXYF on activating mucosal mast cells, downregulating tryptase and c-Fos expression, and reducing serum TNF-αand histamine levels.