Analysis of 4,903 children with diarrhea across six low-resource countries revealed fecal hemoglobin as a superior biomarker for detecting intestinal bleeding compared to visual blood detection by caregivers and clinicians. Among four inflammatory markers tested (hemoglobin, lipocalin-2, myeloperoxidase, and calprotectin), hemoglobin showed the strongest association with Shigella infections, with dysentery cases showing nearly 15-fold higher concentrations. The study found moderate accuracy (AUC=0.70) for visual blood detection versus laboratory hemoglobin measurement. This finding addresses a critical diagnostic gap in resource-limited settings where Shigella causes significant childhood morbidity and mortality. The superior performance of fecal hemoglobin suggests potential for developing point-of-care diagnostic tools that could improve treatment decisions and reduce unnecessary antibiotic use in pediatric diarrheal disease. However, this cross-sectional preprint study awaits peer review, and the practical implementation of hemoglobin-based diagnostics in low-resource clinical settings remains to be validated. The research represents an incremental but meaningful advance toward better diagnostic precision for one of the leading causes of childhood death globally, though translation to clinical practice will require affordable, rapid testing platforms.