Association of the Lymphocyte-to-C-Reactive Protein Ratio with CT-Suspected Strangulation in Hospitalised Patients with Small Bowel Obstruction: A Retrospective Cohort Study
Hideya Itagaki, Jun Suzuki, Hirohito Metoki, Tomoyuki EndoBackground: Strangulated small bowel obstruction (SBO) is a time-critical emergency, and CT is not always available and is imperfectly accurate, prompting interest in blood-based markers such as the lymphocyte-to-C-reactive protein ratio (LCR). Whether LCR aids early risk assessment is unclear, because any signal may reflect earlier presentation (before CRP rises) or CT-based misclassification. Methods: In a single-centre retrospective cohort of adults hospitalised for SBO, strangulation was defined on contrast-enhanced CT; LCR was calculable in 142 of 200 patients (59 of 80 strangulated, 83 of 120 non-strangulated), and LCR-based analyses were complete-case. Results: A higher LCR was associated with strangulation (adjusted odds ratio 1.31 per log-unit, 95% CI 1.03–1.66; for an internally derived Youden cut-off of LCR > 0.269, adjusted odds ratio 2.42, 95% CI 1.05–5.55), but this attenuated to non-significance after adjustment for presentation time (2.23, 95% CI 0.95–5.21). Discrimination was poor (AUC 0.63): at the cut-off, sensitivity was 67.8% (95% CI 55.1–78.3), specificity was 55.4% (44.7–65.6), the positive likelihood ratio was 1.52 (1.13–2.05), and the negative likelihood ratio was 0.58 (0.38–0.88). When markers were oriented consistently, LCR did not discriminate better than CRP alone. Conclusions: An elevated LCR was associated with CT-suspected strangulation but showed poor discriminative power; the proposed threshold is exploratory and requires independent validation rather than clinical use.