Role of computed tomography in the assessment of caustic ingestion severity: A comprehensive review

Abstract

Caustic ingestion is a relatively rare but potentially catastrophic gastroenterological emergency. Upper gastrointestinal (GI) endoscopy is currently regarded as the gold standard modality not only to assess the depth and the extension of GI caustic injury, but also to guide the appropriate treatment. Intriguingly, contrast-enhanced computed tomography (CECT) has recently emerged as a promising non-invasive and more accurate alternative to endoscopy in this setting. However, to date, evidence concerning the role of CECT as an alternative or complementary diagnostic tool to endoscopy in caustic ingestion is still limited. The aim of our review was to summarize and discuss the current evidence concerning the role of CECT in the emergency diagnosis of caustic ingestion and its value in assessing injury severity among non-pediatric patients.

Key Words: Caustic ingestion; Corrosive ingestion; Contrast-enhanced computed tomography; Computed tomography; Endoscopy; Upper gastrointestinal endoscopy

Core Tip: Upper gastrointestinal endoscopy has traditionally been the mainstay for the severity assessment in caustic ingestion, driving proper treatment and dictating patient prognosis. However, contrast-enhanced computed tomography (CECT) has emerged as a promising non-invasive alternative to endoscopy. Nevertheless, to date, evidence concerning the role of CECT in the diagnostic process of caustic ingestion is still limited. Our study aimed to review the current evidence concerning the role of CECT in the severity assessment of caustic ingestion.

INTRODUCTION

Caustic ingestion is a relatively rare but potentially catastrophic gastrointestinal (GI) emergency[1-3]. As opposed to the pediatric population, ingestion in adults is more often suicidal in intent, being associated with high morbidity and mortality[1-4].

The management of caustic ingestion is challenging and typically requires a multidisciplinary approach encompassing not only the gastroenterologist but also the emergency physician, the surgeon, the anaesthesiologist, the radiologist, the otorhynolaryngologist, and the psychiatrist[1-3].

Early esophagogastroduodenoscopy (EGD) has traditionally been the cornerstone of the diagnostic approach[1-3,5]. Endoscopy is still considered the gold standard modality for assessing the severity and extension of caustic ingestion injury, and its findings are pivotal in dictating further treatment and predicting patient prognosis[1-3,5]. In this regard, esophagogastric damages are generally graded according to Zargar’s classification[6]. In patients with extensive necrosis (grade 3b) and/or evidence of perforation, emergency surgery is advocated, whereas patients with lower grade injuries (grades ≤ 3a) are typically managed non-operatively[1-3].

However, the diagnostic role of EGD in caustic ingestion has been questioned in the last decade[7-10]. Indeed, endoscopy has been reported as being unable to accurately assess the depth of intramural necrosis, thus potentially leading to unnecessary emergency surgery and its associated negative impact on survival and digestive function[3,9,11] or to inappropriate conservative treatment[12]. Although the need for resection may be assessed intraoperatively for the intra-abdominal organs[13], an accurate surgical exploration of the thoracic esophagus is not achievable, with the decision to perform an emergency esophagectomy being based solely on endoscopic features[11,14,15]. Thus, a highly accurate diagnostic tool for assessing the severity of caustic ingestion injury is crucial for the safe and effective management of these patients.

In this scenario, contrast-enhanced computed tomography (CECT) has emerged as a promising non-invasive diagnostic modality for the assessment of caustic ingestion severity, especially in establishing the need for emergency surgery, whose morbidity and mortality remain high even among referral centers[7-9].

Various experts and the consensus of the World Society of Emergency Surgery have suggested the introduction of CECT as the first-line diagnostic modality in the emergency management of caustic ingestion[7,16,17]. Nevertheless, evidence-based guidelines assisting the involved clinicians are lacking in Western Countries, and uncertainty persists about the best clinical practice[18-20]. Indeed, EGD is widely performed in real-life clinical practice as the first-line diagnostic tool in this setting[18-20]. Moreover, an evidence-based practice guideline has been recently released by the Indian Society of Gastroenterology, confirming EGD as the preferred initial approach for evaluating caustic injury and reserving CECT only for specific situations[21]. However, evidence regarding the value of CECT in assessing caustic ingestion severity is still limited. The present review aimed to summarize and critically evaluate the current state of the evidence on the role of CECT in the emergency diagnosis of caustic ingestion and its value for assessing injury severity among non-pediatric population.

LITERATURE SEARCH

A literature search covering PubMed (MEDLINE) and EMBASE up to March 2025 was conducted in order to identify relevant articles evaluating computed tomography (CT) in assessing caustic ingestion severity. The medical search strategy used the keywords “caustic ingestion” or “corrosive ingestion” combined with “computed tomography” or “CT”. The search strategy was restricted to studies involving humans and English articles. Abstracts, case reports, case series (< 10 cases), review articles, position papers, editorials, commentaries, and book chapters were omitted. Studies involving pediatric patients were also excluded. The reference lists from identified papers were hand-searched to recognize any further studies.

ROLE OF CT IN EVALUATING THE SEVERITY OF CAUSTIC INGESTION

Evidence

A total of 10 articles were included[22-31]. All but 4 retrospective studies[22,29-31] were prospective in nature[23-28]. All of the included studies were monocentric[22-31]. The main features of the included papers are listed in Table 1.

Table 1 Summary of studies reporting on the role of contrast-enhanced computed tomography in the emergency diagnosis of caustic ingestion.

Ref.	Country	Enrollment period	Stud design	Patients, n	Inclusion criteria	Exclusion criteria	Study aim	Results
Lurie et al[22], 2013	Israel	2000-2012	R	23	Adult patients (> 18 years) with caustic ingestion who underwent both CT and EGD within 48 hours of hospital admission		To evaluate the role of CT in assessing the severity of caustic injury	Endoscopy grading higher than CT grading in 14 patients (66%). Sensitivities of endoscopy grades 2b/3 to predict mortality and emergency laparotomy: 1 and 0.8, respectively. Specificities of endoscopy grades 2b/3 to predict mortality and emergency laparotomy: 0.38 and 0.37, respectively. Sensitivities of CT grade 3 to predict mortality and emergency laparotomy: 0.4 and 0.28, respectively. Specificities of CT grade 3 to predict mortality and emergency laparotomy: 0.94 and 0.93, respectively
Chirica et al[23], 2015	France	2000-2007 (1st stage). 2007-2012 (2nd stage)	R (1st stage). P (2nd stage)	197	Adult patients (> 16 years) with Zargar grade 3b esophageal necrosis	Patients with signs of peritonitis, hemodynamic instability, or Zargar grades < 3b	To evaluate the role of CT in selecting patients with Zargar grade 3b esophageal necrosis for emergent esophagectomy	Higher overall survival in the CT group compared to the routine-esophagectomy group in the crude (HR: 0.43; 95%CI: 0.21–0.85; P = 0.015) and the matched analysis (HR: 0.36; 95%CI: 0.16–0.79; P = 0.011). Native functioning esophagus rate higher in the CT group (38 % vs 1 %, P < 0.0001)
Chirica et al[24], 2016	France	2013-2014	P	120	Adult patients (> 16 years) with caustic injury	Patients with signs of peritonitis or hemodynamic instability	To evaluate the role of CT for the emergency diagnostic work-up of caustic injury	CT-alone algorithm would have spared 19 unnecessary esophagectomies and 16 explorative laparotomies compared with an endoscopy-alone algorithm. Endoscopy never rectified a wrong CT decision. CT never indicated transmural necrosis in low-grade endoscopic injuries
Bahrami-Motlagh et al[25], 2017	Iran	2015	P	34	Adult patients (> 15 years) with caustic injury	Patients with hemodynamic instability, third-degree burns of the hypopharynx, respiratory distress, history of a chronic disease or lesion in stomach/esophagus, or suspected GI perforation	To evaluate the screening performance characteristics of CT in caustic injury	Agreement rate between CT and endoscopy regarding the grade of esophageal and gastric injuries: Moderate (k = 0.38; P = 0.001) and fair (k = 0.17; P = 0.038), respectively. Sensitivity and specificity of CT in detecting esophageal damage: 96.29 and 57.14, respectively. Sensitivity and specificity of CT in detecting gastric damage: 89.65 and 40.00, respectively. AUROC of CT in the detection of esophageal and gastric damages: 0.76 (95%CI: 0.52-1.00) and 0.64 (95%CI: 0.35-0.94), respectively
Mensier et al[26], 2020	France	2014-2017	P	30	Patients with Zargar grade 3b gastric necrosis		To identify CT signs of irreversible gastric necrosis in Zargar 3 gastric necrosis	MPD consistently found in patients who underwent surgery for GI distress, and consistently absent in unoperated patients (except in one patient who refused surgery). Sensitivity and specificity of MPD for irreversible gastric necrosis: 80% and 95%, respectively. Positive and negative predictive values of MPD for irreversible gastric necrosis: 88% and 90%, respectively
Assalino et al[27], 2022	France	2013-2019	P	414	Adult patients (> 16 years) with caustic injury		To evaluate outcomes of caustic ingestion patients managed by a CT-based algorithm and the feasibility of abandoning emergency endoscopy	On crude analysis, similar overall survival in endoscopy-CT and CT-only algorithm groups; better functional outcomes in the CT-only group. On propensity match analysis, similar functional outcomes and overall survival in both groups. On multivariate analysis, intentional ingestion (P < 0.016), age (P < 0.0001), and the CT grade of esophageal injuries (P < 0.0001) were independent predictors of survival. The CT grade of esophageal injuries was the only independent predictor of success (P < 0.0001)
Tosca et al[28], 2022	Spain	1995-2021	P	532	Adult patients (> 15 years) with caustic injury	Doubtful or nonsignificant intake of a very low volume of a caustic substance	To compare a diagnostic algorithm based on predictive factors of an adverse clinical course (predictive algorithm) with a CT-based (radiological algorithm) and a combined approach based on the kind of ingestion, symptoms, and endoscopy (classical algorithm)	Significantly higher sensitivity for detecting any adverse outcome of predictive algorithm (87.1%; 95%CI: 77.3–93.0) than radiological (64.7%; 95%CI: 41.3–82.7) and classical (51.4%; 95%CI: 40.0–63.1) ones. Higher specificity for detecting any adverse outcome of predictive (96.1%; 95%CI: 93.9–97.5) and classical algorithm (98.7%; 95%CI: 97.2–99.4) than radiological one (70.0%; 95%CI). Significantly higher diagnostic OR of predictive (167.2; 95%CI: 71.9–388.7) and classical (80.5; 95%CI: 31.7–204.3) algorithms than radiological one (4.3; 95%CI: 0.8–22.9). Significantly higher proportion of patients requiring no examination for predictive algorithm (50.6%; 95%CI: 46.2%–55.1%) than classical (34.5%; 95%CI: 30.5%–38.6%) and radiological ones (0.0%; 95%CI: 0.0%–0.0%)
Chen et al[29], 2022	Taiwan	2014-2019	R	163	Adult patients (> 18 years) with caustic injury		To evaluate a diagnostic and management algorithm that combines EGD and CT for rapid triage	Significant correlation of EGD grade with the emergency surgical need in both univariate (OR = 8.556; 95%CI: 1.622–45.136; P = 0.011) and multivariate analysis (OR = 8.555; 95%CI: 1.559–46.942; P = 0.013). No significant correlation of CT grade with the emergency surgical need in both univariate (OR = 2.250; 95%CI: 0.497–10.178; P = 0.292) and multivariate analysis (OR = 0.350; 95%CI: 0.028–4.360; P = 0.415). AUROC of EGD, CT, and combined EGD-CT for emergency surgical need: 0.82 (P = 0.002), 0.58 (P = 0.420), and 0.78 (P = 0.007), respectively
Kaewlai et al[30], 2023	Thailand	2016-2021	R	17	Adult patients (> 18 years) with caustic injury who underwent CT within 72 hours of their admission	Endoscopy or surgery not performed	To identify and assess the CT findings differentiating the lack of transmural GI necrosis from its presence and the diagnostic performance of individual CT findings in diagnosing transmural GI necrosis	The highly differentiating CT findings between those with and without transmural GI necrosis were esophageal wall thickening (100% vs 42%, 0.001; 100% sensitive), gastric abnormal wall enhancement and fat stranding (100% vs 57%, 0.006; 100% sensitive), and gastric absent wall enhancement (46% vs 5%, 0.007; 100% specific). The intra- and interobserver agreements were 47%–100%, and 54%–100%, which increased to 53%–100%, and 60%–100%, respectively, when considering only radiologists’ reinterpretations
Scriba et al[31], 2024	South Africa	2017-2023	R	100	Adult patients with caustic injury	Patients managed for only the chronic sequelae of corrosive ingestion and those where acute management data was lacking	To investigate the applicability of parameters for predicting full-thickness necrosis and mortality	Good predictive performance for full-thickness necrosis of Zargar ≥ 3b, grade 3 CT, pH, base excess, and lactate, on multivariate analysis. Best predictive performance for full-thickness necrosis of endoscopy (AUROC = 0.850)

R: Retrospective; CT: Computed tomography; EGD: Esophagogastroduodenoscopy; P: Prospective; HR: Hazard ratio; CI: Confidence interval; GI: Gastrointestinal; AUROC: Area Under the Receiver Operating Characteristic Curve; MPD: Mucosal perfusion defect; OR: Odds ratio; GI: Gastrointestinal.

In 2013, et al[22] first retrospectively evaluated the role of CT in assessing the severity of caustic ingestion, comparing endoscopic and CT findings in 23 patients. Endoscopic findings were graded according to the Zargar classification[6], whereas the following CT grading was adopted: Grade 0 – normal; grade 1 – edematous parietal thickening; grade 2 – grade 1 plus soft tissue infiltration; grade 3 – grade 2 plus intraparietal air, free mediastinal/peritoneal air or fluid collection. The authors found CT to be much less sensitive and more specific than EGD in predicting both the mortality and the need for emergency surgery. Indeed, Zargar grades 2b/3 had sensitivities of 1 for mortality and 0.8 for emergency laparotomy compared with the sensitivities of 0.4 and 0.28, respectively, for CT grade 3. Conversely, Zargar grades 2b/3 had specificities of 0.38 for mortality and 0.37 for emergency surgery, compared with those of 0.94 and 0.93, respectively, for CT grade 3. Furthermore, underestimation of the severity of the caustic injury by CT was observed in 14 out of 23 included patients. Thus, the authors concluded that emergency surgical decisions should not rely solely on CT findings. Of interest, a letter from Lurie’s group clarified that the CT used were all of the third generation, making it unlikely that a limited resolution of the CT machines might have contributed to the poor performance of CT[32,33]. Moreover, the median times to EGD and CT in the 14 patients with higher endoscopy grading relative to CT grading were 3 hours and 5.5 hours, respectively, making it improbable that the reported underestimation of the severity of corrosive injury by CT might be explained by the temporal relationship between the diagnostic modalities[32,33]. However, the main study limitations included small sample size, retrospective nature, the stringent criteria adopted to designate necrosis (the highest CT grade encountered only patients with signs of perforation), and the blindness of the radiologist but not of the endoscopist to the clinical scenario.

Later on, Chirica et al[23] compared outcomes after endoscopy-guided emergency esophagectomy vs emergency esophagectomy based on CT evidence of transmural necrosis in a before/after study including 197 patients with Zargar grade 3b esophageal necrosis. As opposed to the study by Lurie et al[22], CT criteria for esophageal necrosis were derived from those reported in intestinal ischemia[34,35]. Esophageal transmural necrosis was defined by the detection of at least two of the following signs: Parietal blurring, periesophageal-fat blurring, and parietal non-enhancement. Before 2007, all patients with grade 3b esophageal necrosis on endoscopy were surgically treated. Conversely, after 2007, CT was added to the routine management of caustic ingestions, and only patients with CT evidence of transmural necrosis underwent esophagectomy, with the remainder being treated conservatively. Compared to the routine-esophagectomy group (n = 125), the CT group (n = 72) had significantly higher overall survival in both the crude (P = 0.015) and the matched analysis (P = 0.011). Moreover, no deaths occurred among patients managed without emergency esophagectomy according to CT findings, and 38% of patients within the CT group had their functioning native esophagus at the end of follow-up, as opposed to 1% only in the endoscopy group (P = 0.01). When the decision relied solely on EGD, 99% (124/125) of patients with grade 3b damages were treated with esophagectomy or esophagogastrectomy compared with only 35% (25/72) when EGD and CT were combined. Thus, CT was able to avoid unnecessary esophagectomy in approximately two-thirds of the included patients. Finally, the authors concluded that the decision to perform emergency esophagectomy should rely on CT.

In 2016, the same group prospectively explored the usefulness of CT in all grades of caustic injury, specifically addressing the putative adoption of CT as the sole diagnostic tool in decision-making, obviating the need for urgent endoscopy. Transmural esophageal necrosis was radiologically defined as previously reported[34,35], whereas full-thickness gastric necrosis was referred as the absence of post-contrast gastric wall enhancement. Interestingly, decision-making based solely on CT spared 19 unnecessary esophagectomies and 16 exploratory laparotomies compared with an endoscopy-alone algorithm. Moreover, the combination of EGD and CT did not improve decision-making based solely on CT. Indeed, EGD never rectified a wrong CT-based decision. Notably, CT never indicated transmural necrosis in low-grade endoscopic injuries. Worth mentioning, interobserver agreement between radiologists with various degrees of experience was good in the assessment of esophageal necrosis (kappa = 0.73) and excellent in gastric necrosis (kappa = 0.8), suggesting a reliable reproducibility outside referral centers. Finally, based on their findings, the authors suggested that the emergency algorithm for the severity evaluation of caustic injuries may rely on CT alone[24].

Subsequently, a small prospective study from Iran compared endoscopy and CT for the severity assessment of caustic ingestion injury. A different CT grading system was adopted, embracing the following 4 grades: (1) No definite swelling; (2) Edematous wall thickening without soft tissue involvement; (3) Edematous wall thickening with soft tissue infiltration plus well-demarcated tissue interface; and (4) Edematous wall thickening with soft tissue infiltration plus blurring of tissue interface or localized periesophageal/periaortic fluid collection[3,36]. The agreement rate between CT and EGD for esophageal and gastric injuries grading was moderate (K = 0.38; P = 0.001) and fair (K = 0.17; P = 0.038), respectively. The sensitivity and specificity of CT in detecting esophageal injury were 96.29 and 57.14, respectively. These measures were 89.65 and 40.00, respectively, for gastric damage. Finally, the area under the receiver operating characteristic curve (AUROC) of CT for the identification of esophageal and gastric injuries was 0.76 (95%CI: 0.52-1.00) and 0.64 (95%CI: 0.35-0.94), respectively. As opposed to Chirica’s group findings, the authors concluded that the correlation between EGD and CT for injury grading was not high enough to obviate the need for EGD. However, this study presented several limitations potentially affecting its results. First of all, the small sample size. Second, the interpretation of CT studies by one expert radiologist only. Third, the reference standard was endoscopy, and no data were provided regarding the further management, the follow-up, and the mortality of the included patients. Lastly, no information was provided regarding the timing of the diagnostic examinations and the time interval between CT and endoscopy[25].

In 2020, Mensier et al[26] prospectively evaluated the value of CT in predicting irreversible gastric necrosis among Zargar 3 gastric injuries. Eight CT signs were addressed: Maximal thickness of the gastric wall, submucosal edema, intramural pneumatosis, peri-gastric fat infiltration, mucosal enhancement defects, pneumoperitoneum, portal venous air, and intraperitoneal fluid. The authors reported that the CT evidence of a gastric mucosal perfusion defect (MPD) was observed in all patients who were surgically treated for GI distress. In contrast, it was consistently absent in patients treated conservatively, except for the one who refused surgery. Indeed, sensitivity, specificity, positive and negative predictive values of MPD for irreversible gastric necrosis were 80%, 95%, 88%, and 90%, respectively. To be noted, in all patients with CT evidence of MPD who underwent total gastrectomy, transmural necrosis was histologically confirmed. Intriguingly, excluding the two patients surgically treated for GI hemorrhage and the patient who refused surgery, the sensitivity, specificity, positive predictive value, and negative predictive value of MPD on CT were each 100%. Finally, CT could have provided a prompt diagnosis of irreversible gastric necrosis and was shown to be more effective than a strategy based on endoscopy and the use of clinico-biological severity criteria for the diagnosis of irreversible gastric necrosis. Accordingly to Chirica’s findings, the authors concluded that CT should replace EGD in the emergency evaluation of caustic injury.

Subsequently, a large prospective single-center study from Chirica’s group evaluated the adoption of a CT-only diagnostic algorithm for caustic ingestion, showing that EGD may be safely obviated. Indeed, crude analysis showed that overall survival was comparable in both groups, whereas functional outcomes were higher in the CT-only group. Moreover, propensity-matched analysis showed that survival and functional outcomes were similar between the combined endoscopy-CT group and the CT-only group. On multivariate analysis, intentional ingestion (P < 0.016), age (P < 0.0001), and the CT grade of esophageal damages (P < 0.0001) were independent predictors of survival, with the latter being the only independent predictor of success (P < 0.0001). Notably, the CT evidence of full-thickness necrosis was histologically confirmed in 36 out of the 37 surgical specimens, with only one futile esophagectomy encountered due to CT misinterpretation in the early study period. Finally, all the CT slides were read by the radiologists on call and graded according to a recently published classification[37]. The main limitation of the study was the absence of randomization, potentially questioning the validity of its results[38]. However, running a randomized controlled trial on this topic would face significant challenges in patient enrollment due to the rarity of the disease. Furthermore, given the current state of the evidence, randomization to an endoscopy-only algorithm arm could raise major ethical concerns. Anyway, the propensity match analysis performed by the authors partially compensated this shortcoming[27].

Conversely, a large prospective study from Spain compared a diagnostic algorithm based on predictive features of an adverse clinical course (predictive algorithm) with both a CT-based (radiological algorithm) and a combined approach based on the kind of ingestion, symptoms, and EGD (classical algorithm). The predictive algorithm showed a significantly higher sensitivity than the other two for the detection of any adverse outcome, and the specificities of the classical and predictive approaches were higher than the radiological one. Both the classical (80.5; 95%CI: 31.7–204.3) and the predictive (167.2; 95%CI: 71.9–388.7) algorithms had significantly higher diagnostic odds ratios than the radiological one (4.3; 95%CI: 0.8–22.9). Finally, a better diagnostic resource consumption was observed with the predictive algorithm. Indeed, the percentage of patients requiring no examination was significantly higher for the predictive algorithm (50.6%; 95%CI: 46.2%–55.1%) than for the classical (34.5%; 95%CI: 30.5%–38.6%) or the radiological one (0.0%; 95%CI: 0.0%–0.0%). However, the main limitation of this study was the very low sample size of the radiological algorithm group. Indeed, CT was performed by clinical indication rather than by protocol in only 27 out of 532 of the included patients[28].

A recent retrospective study from Taiwan enrolling 163 patients evaluated a diagnostic algorithm combining EGD and CT. CT was shown to be crucial to determine the need for surgical need or additional EGD in patients with clinically suspected perforation. Conversely, EGD alone was sufficient for determining admission necessity in those without suspected perforation, with additional CT benefiting only those with deteriorating signs/symptoms. The CT classification proposed by Ryu et al[36] in 2010 was adopted by the authors. Among patients with endoscopic Zargar ≥ 2b and/or GI/systemic complications receiving both EGD and CT, endoscopy was shown to have a significant correlation with the emergency surgical need in both univariate [odds ratio (OR) = 8.556; P = 0.011] and multivariate settings (OR = 8.555; P = 0.013). Conversely, CT grade was shown to have no significant correlation. The AUROC of EGD and CT for surgical need was 0.82 (P = 0.002) and 0.58 (P = 0.420), respectively, indicating an excellent discrimination for EGD and a poor one for CT. Moreover, although combined EGD and CT grading showed an acceptable discrimination (AUROC = 0.78; P = 0.007), the EGD-originated AUROC was not further increased by the additional CT grade. However, this study presented several limitations. First of all, its retrospective nature and the absence of a definite study protocol. Moreover, worth mentioning, the authors reported that 21 out of 163 included patients underwent emergency surgery, revealing six perforation cases and severe necrosis in some cases, as confirmed by pathology. However, the correlation between endoscopic and/or CT injury grade and final surgical pathology was not clearly reported. Finally, only 67 out of the 163 enrolled patients underwent emergency CT, with 42 patients affected by caustic injury ≥ Zargar’s 2b or GI/systemic complications not receiving CT[29].

A very small retrospective study from Thailand evaluated the performance and reliability of CT findings of transmural GI necrosis, as compared to the reference standards (endoscopy or surgery). The authors reported that the highly discriminating features for the presence and the absence of full-thickness GI necrosis were esophageal wall thickening (100% vs 42%, 0.001; 100% sensitive), gastric abnormal wall enhancement and fat stranding (100% vs 57%, 0.006; 100% sensitive), and gastric wall non-enhancement (46% vs 5%, 0.007; 100% specific). To be noted, the intra- and interobserver agreements were 47%–100%, and 54%–100%, respectively, raising to 53%–100%, and 60%–100%, respectively, when taking into consideration only radiologists’ reinterpretations[30].

Finally, a recent retrospective study from a sub-Saharan African setting showed that Zargar ≥ 3b, grade 3 CT according to Chirica’s grading[16], pH, base excess, and lactate have good predictive value for transmural necrosis in multivariate analysis, with EGD (AUROC 0.85; P < 0.001) performing better than CT (AUROC 0.788; P = 0.016) and the other variables. However, this study was limited by its retrospective nature and by the very low number of patients who underwent CT compared to EGD, which may have affected the accuracy of ROC curves and predictive models for CT grading. Indeed, only 17 out of the 100 enrolled patients were evaluated by the use of CT, of which 14 also underwent endoscopy[31] (Table 1).

CONCLUSION

EGD has historically been regarded as the gold standard modality for assessing caustic ingestion severity and planning further treatment according to Zargar’s classification[1-3,5,6]. The most severe acute complication of caustic injury remains full-thickness necrosis with perforation resulting in significant mortality[2,4,14]. An early and accurate identification of transmural necrosis, allowing for timely surgery before the occurrence of perforation, is crucial for improving the outcomes[1-3,5]. However, the diagnostic accuracy of EGD in this setting has been questioned in the last decade[7-10]. The major drawback of EGD has been reported to be its inability to predict accurately the depth of intramural necrosis, potentially leading to futile emergency surgery and its associated negative impact on survival and digestive function[3,10,11] or to inappropriate conservative treatment[12]. In this scenario, CECT has emerged as a promising diagnostic tool in evaluating accurately the depth of intramural necrosis, changing the paradigm of caustic ingestion management[7-10]. Indeed, CT grading has been shown to outperform EGD in selecting patients for emergency surgery, allowing a more accurate evaluation of necrosis depth, compared to EGD and its exclusively luminal assessment[7-10]. Furthermore, as opposed to EGD, CECT may provide crucial information on adjacent organs such as pancreas, spleen, and mediastinum. Additionally, CT is a non-invasive, rapid, and widely available around-the-clock diagnostic tool. The main contraindications are renal failure and contrast medium allergy. Finally, CT is capable of providing important information in situations where EGD may not be safely performed, such as severe oropharyngeal edema[7-10,39].

However, although specialized teams and international consensus have suggested replacing EGD with CT[7,16,17], evidence-based guidelines are still lacking in Western countries, and uncertainty persists about the best clinical practice[19,20]. Indeed, EGD is still recommended worldwide as the first-line diagnostic modality in caustic ingestion, and is largely employed in real-life clinical practice[1-3,5,21].

Although mandatory prior to emergency surgery, current evidence is still limited to safely and effectively replace EGD with CECT. The risk of CT misinterpretation potentially leading to catastrophic consequences exists and should not be underestimated, especially among non-experienced centers. This aspect likely highlights the crucial role of a multidisciplinary approach in the evaluation of caustic ingestion severity[40]. Moreover, discrepancies about the diagnostic performance of CECT in assessing caustic ingestion severity have been observed in our review. These conflicting results may have several potential explanations, including the absence of a standardized CT grading system, differences in definitions, and dissimilarities in CT scanners, techniques, protocols, and interpretation methods. Moreover, the interval time occurring between CECT and the reference standard modality, the radiologist’s experience with this relatively rare condition, and the center’s volume and experience may also have eventually contributed to these disparities in CT results. Anyway, further large multicenter prospective studies in high-volume referral centers are needed to clarify and better define the role of CECT in caustic injury severity assessment, especially as an alternative modality to EGD. In this scenario, the adoption of a standardized and reproducible CT grading system should be strongly encouraged. The significant rates of morbidity and mortality associated with caustic injury warrant ongoing research in this field.