LAUSR

Dear editor, It was with great interest that we read the article written by Salvador et al. The authors performed an interesting analysis of the esophageal-gastric junction outflow obstruction (EGJOO) and concluded it could be effectively treated with Heller-Dor operation. EGJOO is a new finding seen in high-resolution manometry. The Chicago Classification defines EGJOO as a relaxing disturbance of the lower esophageal sphincter (LES), with integrated relaxation pressure over 15 mmHg and peristaltic esophagus. However, contrary to what Salvador et al. stated, maybe, it is premature to define idiopathic EGJOO as a new disease. Instead, it would be more appropriate to consider idiopathic EGJOO as a manometric manifestation of several possible differential diagnoses. EGJOO is a poorly understood condition, and many patients are even asymptomatic or show spontaneous resolution. The EGJOO can eventually manifest other esophageal disorders, such as the Nutcracker esophagus, and consequently, EGJOO may be an early or an atypical manifestation of a known primary esophageal disease. There are some reports of EGJOO, for example, evolving to achalasia. Besides, the EGJO can be secondary to other conditions, such as eosinophilic esophagitis, esophageal stenosis, hiatus hernia, fundoplication, esophagitis, tumors, diverticulum, and adjustable gastric band. These conditions may be easily underdiagnosed and misclassified as idiopathic EGJOO. To avoid misdiagnosis of a secondary gastroesophageal obstruction, the Chicago Classification suggests the use of imaging tests such as tomography and cross-sectional imaging to rule out any mechanical obstruction. However, Salvador et al. do not mention which tests they used in addition to the barium test and endoscopy as preoperative investigation. Also, the authors did not report if patients were investigated for using certain drugs, such as opioids, that can induce the EGJOO, and the drugs’ withdrawal may lead to EGJOO resolution. Salvador et al. state that, to date, there are no published guidelines on the management of idiopathic EGJOO. Clayton et al., Samo and Qayed, and Tadros and Yodice recently published flow diagrams for EGJOO management. All these studies outlined the importance of making the proper differential diagnosis for the correct identification of the underlying cause and favored the treatment according to patients’ symptomatology. Some studies suggest using amyl nitrite as a therapeutic test to identify patients who would possibly benefit from rupture of the lower esophageal sphincter, including Heller-Dor myotomy or dilatation. The amyl nitrite causes inhibition of LES, helping to determine the etiology of EGJOO. There are other proposed tests, such as the “challenge of 200 ml fast drinks” during manometry, used as a “stress test” for the esophagogastric junction, and tests such as functional imaging probe and endoscopic ultrasound, that provide clinically useful parameters. Salvador et al. included only patients with dysphagia or regurgitation. Patients with a manometric diagnosis of idiopathic EGJOO with chest pain, heartburn, or other extraesophageal symptoms were excluded. Such eligibility criteria in their study may have led to a selection bias, and probably several of the included patients are actually the old diagnosis called achalasia, with incipient or atypical manometric findings. Achalasia is already known to respond to myotomy. * Francisco Tustumi [email protected]