A PROSPECTIVE OBSERVATIONAL STUDY ON ANTIBIOTIC EXPOSURE AND GUT DYSBIOSIS: ROLE OF FECAL CALPROTECTIN AND PROBIOTIC THERAPY
DOI:
https://doi.org/10.22159/ajpcr.2026v19i6.58876Keywords:
Gut dysbiosis, Fecal calprotectin, Probiotics,, AntibioticsAbstract
Objectives: The purpose of this study was to evaluate the severity of gut dysbiosis in patients undergoing antibiotic therapy and investigate associations between probiotic use, antibiotic exposure, and dysbiosis-related biomarkers.
Methods: In a prospective observational study at a single center over 6 months, 100 patients were enrolled. Baseline demographic data, medical and family history, and antibiotic and probiotic prescriptions were documented. Stool samples collected at scheduled intervals were analyzed for fecal calprotectin (FCP) by quantitative assay and for stool pH using a calibrated meter. Probiotic therapy (VSL#3) was prescribed when clinically indicated. Data were summarized and changes in biomarkers were evaluated using non-parametric paired analysis.
Results: A total of 100 patients completed the 6-month observation period. Patients received antibiotics from multiple classes: Cephalosporins, carbapenems (βlactams), fluoroquinolones, tetracyclines, nitroimidazoles, and oxazolidinones. At first follow-up, all patients demonstrated elevated biomarkers, with a median FCP of 128.5±8.4 μg/g and median stool pH of 6.8. Following initiation of probiotic therapy, re-assessment at subsequent follow-up revealed a decline in median FCP to 86.5±4.0 μg/g and median stool pH to 7.2. These changes in FCP and pH were statistically significant using the Wilcoxon signed-rank test.
Conclusion: In this cohort, antibiotic exposure was associated with increased gut-dysbiosis markers. Adjunctive probiotic therapy correlated with a significant reduction in FCP and normalization of stool pH, suggesting partial restoration of intestinal homeostasis. These findings support the value of antibiotic stewardship and indicate that, when antibiotics are unavoidable, co-administration of probiotics may help mitigate dysbiosis and preserve gut health.
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Copyright (c) 2026 Shanti Sagar, Pooja Reddy Kalva, Harshdeep Mara, Pavani Mallikarjun Dyavannavar, Pragathi Reddy Gunnam
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