The efficacy of single-dose 5-fluorouracil therapy in experimental caustic esophageal burn

Corrosive induced esophageal and gastric injury: Histopathological evaluation of surgically resected specimens over a decade in a tertiary care center

BACKGROUND

Caustic ingestion is associated with long-term sequelae like esophageal stricture, gastric cicatrization, and long-term risk of dysplasia or even carcinoma. However, only a few small studies have explored histopathological aspects of caustic-induced esophageal/gastric injury.

MATERIALS AND METHODS

We retrospectively evaluated specimens of patients undergoing surgery due to caustic ingestion-related complications from 2008 to 2020. Pathological examination was conducted by two independent gastro-pathologists to evaluate the extent and depth of the caustic injury, presence or absence of tissue necrosis, type and degree of inflammation, or presence of any dysplastic cells.

RESULTS

A total of 54 patients underwent surgical exploration during the inclusion period and complete details of 39 specimens could be retrieved. The mean age of the included patients was 28.66 ± 9.31 years and 25 (64.1%) were male. The majority of patients (30; 76.9%) had a history of caustic ingestion more than three months before the surgery and the presence of long or refractory stricture was the most common indication for the surgery (20; 51.28%). In the resected specimen, a majority of patients had superficial esophageal or gastric ulcer (90.6%; 60.0%), transmural inflammation (68.8%; 65.6%), transmural fibrosis (62.5%; 34.4%), and hypertrophied muscularis mucosa (78.13%; 53.3%). However, none of the patients had dysplasia in the resected esophageal or gastric specimens.

CONCLUSION

Caustic ingestion leads to mucosal ulceration, transmural inflammation, and transmural fibrosis which might be the reason for refractory stricture in such patients.

Caustic ingestion

Corrosive ingestion is a rare but potentially devastating event and, despite the availability of effective preventive public health strategies, injuries continue to occur. Most clinicians have limited personal experience and rely on guidelines; however, uncertainty persists about best clinical practice. Ingestions range from mild cases with no injury to severe cases with full thickness necrosis of the oesophagus and stomach. CT scan is superior to traditional endoscopy for stratification of patients to emergency resection or observation. Oesophageal stricture is a common consequence of ingestion and newer stents show some promise; however, the place of endoscopic stenting for corrosive strictures is yet to be defined. We summarise the evidence to provide a plan for managing these potentially life-threatening injuries and discuss the areas where further research is required to improve outcomes.

Caustic ingestion in children-A review

Various domestic or industrial chemicals may cause significant upper aerodigestive tract burns. Preventive measures should be up-scaled, especially in the developing world, to reduce the epidemic of accidental victims, largely unsupervised preschool children. External signs do not predict degree of injury. Non-invasive diagnostic screening includes radio-nuclear imaging, but early oesophago-gastroduodenoscopy remains the standard to predict stricture formation from circumferential submucosal scarring. Serial dilation is the mainstay of oesophageal stricture therapy, with oesophageal replacement reserved for severe refractory strictures. Intra-lesional steroid or mitomycin C may decrease the dilatations required for severe strictures, although long-term effects are unknown. Risk of secondary oesophageal carcinoma mandates long-term surveillance.

Effects of tenoxicam in experimental corrosive esophagitis model

Esophageal stricture, one of the important complications of corrosive esophagus, develops following edema and granulation tissue that forms during and after the inflammatory reactions. Tenoxicam, a non-steroid anti-inflammatory drug with a long half-life, prevents various leukocyte functions including phagocyte and histamine secretion by inhibiting prostaglandin synthesis and removes various oxygen radicals in the region of inflammation. We designed this as a histopathological study using tenoxicam in rats for which we created a corrosive esophagus model. After necessary authorizations were obtained, the study was performed in Çanakkale 18 Mart University experimental animal laboratory. Twenty-four Wistar albino rats, weighing 220-240 g, were used for the experiment. Experimental animals were randomized into three groups: tenoxicam group (group T, n:8), control group (group C, n:8), and sham group (group S, n:8). Tenoxicam 0.5 mg/kg/day was administered to animals in group T, where esophageal burn was developed experimentally, 5 mg/kg 0.9% NaCL was administered i.p. to rats in group C for 15 days, once in 24 hours. No procedure was applied to rats in group S. After 15 days, all animals were sacrificed under general anesthesia and their esophagi were extracted. As a result of histopathological evaluation, inflammation and fibroblast proliferation was not observed in rats in the sham group (group S). Intense inflammation was observed in six rats (6+/2-) in the control group, and fibroblast proliferation was observed as 5+/3-. And in treatment groups, inflammation was evaluated as 3+/5-, and fibroblast proliferation as 3+/5-. In our study, histopathologic damage score was higher in the control group (P < 0.005). We deduce that tenoxicam can be useful in the treatment of caustic esophageal injuries in the acute phase, but think that these drugs require further researches and clinical studies before routine clinical use.

Caustic injury of the upper gastrointestinal tract: A comprehensive review

Prevention has a paramount role in reducing the incidence of corrosive ingestion especially in children, yet this goal is far from being reached in developing countries, where such injuries are largely unreported and their true prevalence simply cannot be extrapolated from random articles or personal experience. The specific pathophysiologic mechanisms are becoming better understood and may have a role in the future management and prevention of long-term consequences, such as esophageal strictures. Whereas the mainstay of diagnosis is considered upper gastrointestinal endoscopy, computed tomography and ultrasound are gaining a more significant role, especially in addressing the need for emergency surgery, whose morbidity and mortality remains high even in the best hands. The need to perform emergency surgery has a persistent long-term negative impact both on survival and functional outcome. Medical or endoscopic prevention of stricture is debatable, yet esophageal stents, absorbable or not, show promising data. Dilatation is the first therapeutic option for strictures and bougies should be considered especially for long, multiple and tortuous narrowing. It is crucial to avoid malnutrition, especially in developing countries where management strategies are influenced by malnutrition and poor clinical conditions. Late reconstructive surgery, mainly using colon transposition, offers the best results in referral centers, either in children or adults, but such a difficult surgical procedure is often unavailable in developing countries. Possible late development of esophageal cancer, though probably overemphasized, entails careful and long-term endoscopic screening.

A novel model approach for esophageal burns in rats

Background:

Corrosive esophageal injury causes serious clinical problems. We aimed to create a new experimental esophageal burn model using a single catheter without a surgical procedure.

Materials and methods:

We conducted the study with two groups of 12 male rats that fasted for 12 h before application. A modified Foley balloon catheter was inserted into the esophageal lumen. The control group was given 0.9% sodium chloride, while the experimental group was given 37.5% sodium hydroxide with the other part of the catheter. After 60s, esophagus was washed with distilled water. The killed rats were examined using histopathological methods after 28 days.

Results:

In comparison with the histopathological changes experienced by the study groups, the control groups were observed to have no pathological changes. Basal cell degeneration, dermal edema, and a slight increase in the keratin layer and collagen density of submucosa due to stenosis were all observed in the group subjected to esophageal corrosion.

Conclusion:

A new burn model can thus, we believe, be created without the involvement of invasive laparoscopic surgery and general anesthesia. The burn in our experiment was formed in both the distal and proximal esophagus, as in other models; it can also be formed optionally in the entire esophagus.