Gut dysbiosis and constipation in patients with end-stage renal disease: pathogenic associations and therapeutic interventions.

Chronic kidney disease (CKD) is a global, life-threatening condition that can progress to end-stage renal disease (ESRD) without effective medical intervention. Constipation is among the most common gastrointestinal disorders and is closely linked to disease progression and poor outcomes in patients with ESRD. An increasing body of evidence suggests that both CKD patients and those with constipation experience significant changes in gut microbiota composition and face impaired intestinal barrier function. Dysbiosis of the gut microbiota is characterized by a reduced abundance of short-chain fatty acid-producing bacteria and increased levels of proteolytic and urease-positive bacteria, which are associated with elevated intestinal permeability and renal damage. Given the complex interplay between ESRD, constipation, and gut dysbiosis, microbiota-targeted interventions show promise as potential therapeutic strategies for managing constipation in ESRD patients. This review summarizes the observed changes in the gut microbiota among constipated ESRD patients and explores their potential pathogenic mechanisms. Unlike previous reviews that cover the entire spectrum of CKD, this study focuses specifically on the ESRD population and proposes a bidirectional "microbiota-gut-kidney" vicious cycle framework centered on constipation. Additionally, we synthesize current evidence on microbiota-targeted interventions and highlight the translational gaps and safety considerations relevant to their clinical application.