# Differences by transplant type in stool multiplex PCR testing for acute diarrhea in post-solid organ transplantation

## TL;DR

This study finds that the likelihood of detecting pathogens in stool tests for diarrhea varies among different types of organ transplants.

## Contribution

The study identifies transplant-specific differences in diagnostic outcomes using a multiplex PCR test for acute diarrhea in organ transplant recipients.

## Key findings

- Renal transplant recipients had more frequent positive GI panel results compared to other transplant types.
- Outpatient testing and older transplant age were independently associated with positive GI panel results.
- Positive GI panel results influenced changes in antibiotic management for transplant recipients.

## Abstract

Diarrhea in solid organ transplant (SOT) recipients is common, morbid, and increasingly evaluated using multiplex gastrointestinal PCR panel (GI panel) testing. We aimed to characterize differences between transplant organ types in GI panel evaluation of acute diarrhea in SOT recipients.

We performed a dual-center retrospective cross-sectional study of adult SOT recipients with acute diarrhea who underwent GI panel testing. Demographic, transplant, testing context, and GI panel data were collected. Patients were stratified by transplant type. The primary outcome was a positive GI panel.

Of 300 transplant recipients (58 heart, 65 liver, 68 lung, and 109 renal), 118 had a positive GI panel. Renal transplant status correlated with more frequently positive GI panel and less frequent hospitalization. In a multivariate analysis adjusting for demographic factors, hospitalization, immunosuppression, and transplant age, renal transplantation was independently associated with a positive GI panel compared to lung transplantation (aOR 2.98, 95% CI 1.27-7.16). Older transplant age and outpatient testing were also independently associated with a positive GI panel. The GI panel result was associated with changes to antibiotic management.

In the evaluation of SOT recipients with acute diarrhea, GI panel result varies by transplant type, transplant age, and testing location and may affect subsequent antimicrobial therapy.