Endoscopic Outcomes and Inflammatory Marker Correlation in Adult Patients with Corrosive Substance Ingestion

<b>Background/Objectives:</b> Corrosive substance intake remains a significant public health concern due to its potential for severe gastrointestinal (GI) injury and associated morbidity. Early risk stratification is crucial for appropriate management, yet there is a lack of reliable non-invasive predictors of injury severity. This study aimed to evaluate the clinical characteristics of adult patients with corrosive ingestion and to investigate the correlation between inflammatory markers and endoscopic injury severity. <b>Methods:</b> In this retrospective study, 83 adult patients who underwent esophagogastroduodenoscopy (EGD) following corrosive ingestion between January 2017 and January 2021 were analyzed. Endoscopic injuries were graded using the Zargar classification and categorized as mild (grades 0-2a) or severe (grades 2b-4). Demographic, clinical, endoscopic, and laboratory data, including neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) levels, were recorded. The correlation between inflammatory markers and injury severity was assessed, and receiver operating characteristic (ROC) analysis was performed to determine diagnostic accuracy. <b>Results:</b> Among the patients, 55.4% were female with a mean age of 41.5 ± 17.3 years. Most ingestions were accidental (74.7%), with bleach being the most common agent (41%). Endoscopic injury was detected in 55.4% of patients, predominantly in the stomach and esophagus. Severe injuries were associated with longer intensive care and hospital stays, increased complication rates, and more frequent organ involvement (<i>p</i> < 0.001). A weak but statistically significant correlation was found between injury severity and both NLR (r = 0.357, <i>p</i> = 0.001) and CRP (r = 0.247, <i>p</i> = 0.024). ROC analysis revealed an NLR cut-off of 2.95 (AUC = 0.804) and CRP cut-off of 2.5 (AUC = 0.706) for predicting severe injury. <b>Conclusions:</b> Early endoscopic evaluation remains essential for assessing corrosive injury severity. However, NLR and CRP may serve as useful, non-invasive indicators in predicting injury severity, potentially aiding clinical decision-making, especially in settings where endoscopy is not readily available or is contraindicated.