[Histological evaluation of esophageal stricture in children with caustic burn]

OBJECTIVE

To analyze histological features of esophageal strictures in children with chemical burn following ingestion of household products containing sodium (potassium) hypochlorite, sodium (potassium) hydroxide.

MATERIAL AND METHODS

We analyzed 3 children with complicated caustic esophageal burns. Children at the time of swallowing the caustic were 26.3±4.1 months. Multiple dilatations of esophageal stricture were ineffective. Therefore, extirpation or subtotal resection of the esophagus and esophagocoloplasty were performed. We stained specimens using hematoxylin and eosin, as well as Masson's trichrome.

RESULTS

Severe esophageal burns caused by sodium (potassium) hydroxide and/or sodium hypochlorite are followed by irreversible tissue lesions and non-dilatable stricture. Strictures are localized in the areas of physiological narrowing of the esophagus. The longest stricture follows ingestion of liquid substance. Histological properties include atrophy of glands and mucous membrane, muscle layer substitution by connective tissue and diffuse sclerosis of esophageal wall.

CONCLUSION

Non-dilatable esophageal stricture following caustic burn in children is due to irreversible morphological lesion of esophageal wall with mucous layer atrophy and sclerosis of all layers.

Reactivation of the Hedgehog pathway in esophageal progenitors turns on an embryonic-like program to initiate columnar metaplasia

Columnar metaplasia of the esophagus is the main risk factor for esophageal adenocarcinoma. There is a lack of evidence to demonstrate that esophageal progenitors can be the source of columnar metaplasia. In this study, using transgenic mouse models, lineage tracing, single-cell RNA sequencing, and transcriptomic and epigenetic profiling, we found that the activation of the Hedgehog pathway in esophageal cells modifies their differentiation status in vivo. This process involves an initial step of dedifferentiation into embryonic-like esophageal progenitors. Moreover, a subset of these cells undergoes full squamous-to-columnar conversion and expresses selected intestinal markers. These modifications of cell fate are associated with remodeling of the chromatin and the appearance of Sox9. Using a conditional knockout mouse, we show that Sox9 is required for columnar conversion but not for the step of dedifferentiation. These results provide insight into the mechanisms by which esophageal cells might initiate columnar metaplasia.

Factors affecting the outcome of endoscopic dilatation in refractory post-corrosive oesophageal stricture in Egyptian children: a single-centre study

BACKGROUND

An important complication of corrosive ingestion is oesophageal stricture. Improvements in endoscopes and accessories have supported an increase in the number of patients who are conservatively treated with endoscopic dilations. In this study, we aimed to detect factors affecting the outcome of endoscopic dilatation for refractory post-corrosive oesophageal stricture.

METHODS

This study was carried out in the Paediatric Endoscopy Unit in the Children's Hospital and included 100 children older than 2 years of age of both sexes who had an established diagnosis of post-corrosive oesophageal stricture on repeated endoscopic dilatation sessions. The duration of the condition was more than 6 months, and dilatation failed to achieve a diameter of 14 mm during the first five sessions at 2-week intervals (refractory), excluding other causes of oesophageal stricture.

RESULTS

Males represented 63% of patients. The mean age of enrolled children was 5.9 ± 2.6 years; 90% of patients ingested an alkaline corrosive substance (potash). The total number of dilatation sessions ranged from 16 to 100, with a mean number of sessions ranging from 37.2 ± 14.9. Fifty-four patients (54%) were well controlled by regular endoscopic dilatation with good clinical and endoscopic outcomes, and no more dilatations were needed.

CONCLUSION

Endoscopic dilation is an effective method for managing refractory post-corrosive oesophageal strictures that require a long follow-up period. There are a lot of factors affecting the outcome.