Evaluation of the performance and feasibility of RLDT in detecting Shigella in a primary healthcare facility of rural Bangladesh

Shigellosis remains underdiagnosed due to the lack of rapid, reliable diagnostics. Although Shigella spp. is known for causing dysentery, over 50% of Shigella-associated cases are watery diarrhea. Identifying and treating these cases of watery diarrhea caused by Shigella could be lifesaving, which would require a point-of-care (POC) Shigella test. Evidence-based treatment could also reduce the overuse of antibiotics. We evaluated the feasibility and applicability of the Rapid LAMP-based Diagnostic Test (RLDT) assay for detecting shigellosis in a healthcare facility. Stool samples (n=228) were collected from children seeking facility care during diarrhea and on their follow-up visits from an ongoing case-control study, INSIGHT. The stool samples were tested by the INSIGHT lab personnel using the RLDT for Shigella spp. The lab personnel at a rural primary healthcare facility, Mirzapur Upazila Health Complex (MUHC) in Bangladesh, received training in RLDT and retested the stool samples with RLDT at the MUHC; the results were compared. The acceptance of RLDT at MUHC was also evaluated through questionnaires. After training, the MUHC lab personnel independently performed RLDT. The RLDT tests performed by the MUHC showed sensitivity of 98% and specificity of 99%, with an almost perfect agreement (Kappa = 0.96) compared with the pre-tested RLDT results. The RLDT assay was well received by the MUHC, despite the general challenges of limited manpower and resources at rural health care facilities. This study demonstrates the potential of using RLDT as a POC test in Shigella-endemic countries to support evidence-based treatment, saving lives and reducing inappropriate antibiotic use. KeypointsRLDT, as a simple and accurate diagnostic tool, offers a practical solution for Shigella detection in low-resource settings. Scaling up RLDT will empower health systems by enabling timely diagnoses to guide treatment and reduce antimicrobial resistance.