Repeat multiplex PCR gastrointestinal panel testing within 14 days yields minimal additional diagnostic information: a multicenter cohort study

View abstract Introduction:Expanded multiplex PCR gastrointestinal panels (GIPs) are routinely ordered to diagnose infectious diarrhea. However, recommendations for repeat GIP testing are limited, resulting in variable testing practices. We evaluated the diagnostic yield of repeat GIP testing within 14 days.Methods:We conducted a retrospective cohort study of adults (age ≥ 18 years) tested with GIPs across 12 hospitals and outpatient centers (2019–2024). We analyzed the first diarrheal episode per patient, excluding cases with invalid/missing results and C. difficile results. Repeat testing was defined as a GIP completed within 14 days of an index GIP, excluding confirmatory testing using the same stool sample. The primary outcome was diagnostic yield (new pathogen detection), and the secondary outcome was pathogen persistence (same pathogen detection).Results:Among 16,502 patients, 507 (3.1%) underwent repeat GIP testing within 14 days (median interval: 6.3 days; IQR: 2.7–9.8). Only 4.6% [19/415] index-negative patients and 2.2% [2/92] index-positive patients detected new pathogens on repeat testing, with 51% [47/92] index-positive patients demonstrating persistence of at least one pathogen from their initial test. The number needed to test (NNT) to identify one new pathogen was 24 (95% CI: 16–39) tests overall, and 127 (95% CI: 50–455) tests to identify one new pathogen warranting antimicrobial treatment. Most repeat testing (86% [436/507]) was ordered by a different clinician.Discussion:Repeat GIP testing within 14 days rarely provided new diagnostic information, highlighting the limited utility of early repeat testing. Institutional policies discouraging repeat GIPs within 14 days may improve diagnostic stewardship.

cambridge.org

Impact of Procalcitonin Testing on Antibiotic Use in Patients Hospitalized With Community-Acquired Pneumonia: A Multi-Hospital Cohort Study

Procalcitonin (PCT) testing may guide antibiotic decisions in community-acquired pneumonia (CAP), but real-world evidence of its impact on antibiotic prescribing in the era of shorter antibiotic courses remains limited.MethodsWe conducted a retrospective cohort study of adults with CAP admitted to the wards of 12 hospitals between November 2022 and January 2025. Primary analyses included: (1) PCT testing rates at admission, (2) the association between PCT testing and duration of antibiotic therapy, and (3) among patients initiated on extended-spectrum antibiotics (ESAs), the relationship between PCT results and early de-escalation. We compared outcomes between PCT-tested and untested patients and between those with low (<0.1 μg/L) vs high (≥0.1 μg/L) PCT values using propensity score overlap weighting to control for potential confounders.ResultsAmong 17 290 non–intensive care unit (ICU) admissions for CAP, PCT testing was performed for 10 658 patients (59.5%) within 24 hours of admission. After adjustments, PCT testing was associated with shorter antibiotic duration (adjusted mean difference, −0.32 days; 95% confidence interval [CI], −.52 to −.12) but was not significantly associated with ESA de-escalation compared with no PCT testing (hazard ratio, 1.05; 95% CI, .99–1.12). Patients with low PCT values received shorter antibiotic courses compared with those with high values (adjusted mean difference, −0.56 days; 95% CI, −.85 to −.49).ConclusionsIn non-ICU patients with CAP, PCT testing was associated with modest differences in antibiotic duration, primarily when values were low.

academic.oup.com

Derivation and validation of a prediction model for primary and recurrent Clostridioides difficile infection among the hematopoietic cell transplantation population | Antimicrobial Stewardship & Healthcare Epidemiology | Cambridge Core

Derivation and validation of a prediction model for primary and recurrent Clostridioides difficile infection among the hematopoietic cell transplantation population - Volume 6 Issue 1

doi.org

#IDWeek2025 Posts/Tweets Analysis | Everyday Is A School Day

IDWeek2025 had the lowest post count since 2022 (1,272 posts). While top posters shifted to Bluesky, X remained on par—the key difference was engagement rates favoring Bluesky. Grateful to learn so mu...

kenkoonwong.com

Screening for Helicobacter pylori to Prevent Gastric Cancer

This randomized clinical trial evaluates the effects of Helicobacter pylori stool antigen assessment plus fecal immunochemical testing (FIT), vs FIT alone, on gastric cancer incidence and mortality am...

jamanetwork.com

Meta-analysis of predictors of healthcare-associated Clostridioides difficile infection | Antimicrobial Stewardship &amp; Healthcare Epidemiology | Cambridge Core

Meta-analysis of predictors of healthcare-associated Clostridioides difficile infection - Volume 4 Issue 1

cambridge.org