Related Experiment Video
Updated: Feb 23, 2026

Estimation of Urinary Nanocrystals in Humans using Calcium Fluorophore Labeling and Nanoparticle Tracking Analysis
Published on: February 9, 2021
Gastrointestinal complications induced by sevelamer crystals
Claudia Yuste1, Evangelina Mérida1, Eduardo Hernández1
1Department of Nephrology, Doce de Octubre Hospital, Madrid, Spain.
Background:
Sevelamer is a phosphate binder widely used in chronic kidney disease (CKD) patients. Sevelamer, as well as other resin-based binders, can crystallize leading to the formation of concretions. Sevelamer crystals (SC) have been associated with gastrointestinal (GI) mucosal injury. We describe three new cases of GI lesions associated with SC and review previously reported cases.
Methods:
We describe three new cases of GI lesions associated with SC and review previously reported cases.
Results:
We found 16 previously reported cases of SC-induced GI lesions. The mean patient age was 61 years (interquartile range 51.5-71.75), 62.5% were females and 10 patients were diabetic. In 13 cases, SC was found inside the GI mucosa. Six patients had history of major abdominal surgery. GI bleeding was the most common clinical symptom (n = 7), with three patients presenting with acute abdomen requiring surgical intervention. Although, SC-induced lesions were observed in all GI segments, intestine was involved in 81% of the cases. Endoscopic examination revealed mainly erosions and ulcerations (n = 7) and pseudoinflammatory polyps (n = 5). No association between sevelamer doses and the severity of GI lesions was found. However, diabetics patients seemed to develop GI lesions with smaller doses of sevelamer as compared with non-diabetic patients, in spite of their fewer GI comorbidities.
Conclusions:
SC-induced GI lesions should be considered in CKD patients treated with sevelamer who present GI symptoms, especially lower GI bleeding, once other causes have been ruled out. Diabetics seem more prone to develop SC- associated GI lesions. Sevelamer therapy should be avoided if possible in patients with a history of major abdominal surgery or chronic constipation, because of the high risk of serious GI complications.
Related Concept Videos
Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
Drugs for Peptic Ulcer Disease: Sucralfate as Mucosal Protective Agents
In this scenario, mucosal protective agents like sucralfate play an essential role. Sucralfate, a complex of sulfated sucrose and aluminum hydroxide, demonstrates its usefulness in acidic conditions,...
Chronic Bowel Disorders: Introduction
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
Urinary Tract Calculi II: Pathophysiology and Clinical Manifestations
Peritoneal Dialysis II: Peritoneal Dialysis Systems and Complications
Urinary Tract Calculi III: Medical Management

