Iranian Journal of Colorectal Research

Iranian Journal of Colorectal Research

Injectable Non-Animal Stabilized Hyaluronic Acid/Dextranomer (NASHA/Dx) for Adult Fecal Incontinence: Mechanisms, Clinical Outcomes, and Its Role in Contemporary Management

Document Type : Review Article

Authors
Sajad Ahmad Salati 1
Aasim Ajaz Salati 2
1 Department of Surgery, College of Medicine , Qassim University , Saudi Arabia
2 Department of Pharmacology, Government Medical College, Jammu, India
10.30476/acrr.2026.112212.1289
Abstract
Background: Adult fecal incontinence (FI) is a common and debilitating condition that significantly impairs physical, psychological, and social quality of life (QoL). Injectable non-animal stabilized hyaluronic acid/dextranomer (NASHA/Dx) has emerged as a minimally invasive treatment option for patients who remain symptomatic despite optimized conservative therapy. This narrative review evaluates the mechanism of action, clinical outcomes, patient selection criteria, and the contemporary role of NASHA/Dx in the management of adult FI.
Methods: A comprehensive literature search was performed in PubMed/MEDLINE, Embase, and Scopus, emphasizing high-quality evidence published from 2010 through June 2026. Landmark randomized controlled trials, long-term prospective studies, systematic reviews, and contemporary international clinical practice guidelines were critically evaluated and narratively synthesized.
Results: NASHA/Dx acts through immediate tissue augmentation, followed by progressive collagen deposition and tissue remodeling around dextranomer microspheres. Clinical studies demonstrate significant reductions in FI episodes, sustained improvements in QoL, and a favorable safety profile in appropriately selected patients, particularly those with passive FI associated with internal anal sphincter dysfunction. Repeat (“top-up”) injections may enhance or maintain therapeutic benefits in selected individuals. Current evidence supports NASHA/Dx as an effective intermediate treatment between conservative management and more invasive interventions.
Conclusion: Injectable NASHA/Dx is a safe, minimally invasive, and evidence-based treatment for selected adults with FI who do not respond to conservative management. Careful patient selection and integration within a multidisciplinary treatment pathway are essential to achieving optimal outcomes. Further research should focus on long-term durability, standardized outcome measures, and refinement of patient selection criteria.

Highlights

Sajad Ahmad Salati (Google Scholar)

Keywords
Fecal Incontinence
Hyaluronic Acid
Dextranomer
Injections
Treatment Outcome
Patient Selection
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