Esophageal Webs and Rings

Etiology

The etiology of esophageal webs and rings remains a controversial topic. Several conditions have correlated with esophageal webs and rings. Esophageal webs are classically associated with Plummer-Vinson syndrome which is classically a triad of dysphagia, iron-deficiency anemia, and esophageal webs.[3] Other associated conditions include Zenker diverticulum, epidermolysis bullosa, pemphigus vulgaris, and bullous pemphigoid.[4][5][6][7] Esophageal rings, on the other hand, are almost always associated with a hiatal hernia.[8] They also correlate with eosinophilic esophagitis.[9]

Epidemiology

Because most webs and rings are asymptomatic, the true prevalence of these lesions is unclear.[10] Esophageal webs and rings are each identified in 5% to 15% of patients undergoing upper endoscopy for dysphagia.[11]

Pathophysiology

The pathophysiology of esophageal webs and rings is poorly understood. Chronic inflammation can irritate the esophageal wall and produce these lesions.[12] They are also present in the pediatric population suggesting a congenital origin.[13] If webs and rings are big enough, they can narrow the esophageal lumen causing dysphagia and food impaction.

Histopathology

Esophageal webs are usually found in the proximal esophagus and have a covering of squamous epithelium.[11] Esophageal rings, on the other hand, are usually located in the distal esophagus and can be covered with squamous epithelium, columnar epithelium, or both depending on their location to the squamocolumnar junction:

• The A rings are located proximal to the squamocolumnar junction. They are covered entirely with squamous epithelium. They are uncommon and usually nonpathological.
• The B rings or Schatzki rings are located precisely at the squamocolumnar junction. The proximal part is covered with squamous epithelium, and the distal portion is covered with columnar epithelium. They are the most common type of ring and can become symptomatic.
• The C rings are located distal to the squamocolumnar junction. They are covered entirely with columnar epithelium. They are the least common, rarely symptomatic, and usually represent diaphragmatic indentation of the esophagus.[14]

History and Physical

Most esophageal webs and rings cause no symptoms. Patients can become symptomatic if an esophageal web or ring protrudes into the lumen enough to cause esophageal narrowing. Patients usually present with intermittent dysphagia to solid food. Some patients may develop food impaction and will present with acute dysphagia and inability to swallow saliva. In the case of Plummer-Vinson syndrome, patients may demonstrate the triad of dysphagia, esophageal webs, and iron deficiency anemia.[15]

Isolated esophageal webs and rings usually do not have physical exam findings. However, a comprehensive physical exam may point towards an associated condition. Plummer-Vinson syndrome might have the skin manifestations of iron deficiency anemia including koilonychia, glossitis, and cheilosis.[3] A skin examination may reveal bullous lesions consistent with epidermolysis bullosa or pemphigus vulgaris.

Evaluation

Laboratory testing is rarely useful in patients with suspected esophageal webs or rings. It might be reasonable to obtain a complete blood count and iron studies to look for iron deficiency. However, patients with dysphagia need to be evaluated with barium swallow and/or upper endoscopy. Both procedures can help differentiate between the different etiologies of dysphagia.

A barium swallow is particularly useful in delineating the cause of the esophageal lumen obstruction. It can identify esophageal webs, rings, strictures, tumors, and extraesophageal compression. An esophagogastroduodenoscopy (EGD) is usually necessary for the confirmation of the diagnosis. On EGD, esophageal webs appear as thin membranes that do not span the entire circumference of the esophagus.[3] Esophageal rings also appear as thin membranes, but they span the entire circumference of the esophagus.[15] EGD can also identify other causes of dysphagia including stricture, polyps, and tumors. Moreover, it can allow biopsy of the lesions when suspicion of malignancy exists. Conditions associated with esophageal webs and rings may be identified with an EGD including eosinophilic esophagitis, hiatal hernia, and Zenker’s diverticulum.

Treatment / Management

The main initial treatment of symptomatic esophageal webs and rings is endoscopic esophageal dilatation. The goal of treatment is the relief of dysphagia and the prevention of symptom recurrence. It is common for esophageal webs to rupture during a diagnostic EGD. Esophageal dilatation is still an option on esophageal webs that have partially ruptured.[16] Esophageal rings require a biopsy before dilatation to rule out eosinophilic esophagitis. Following dilatation of esophageal rings, patients often require therapy with a proton pump inhibitor (PPI) because most rings are close to the gastroesophageal junction.[17] Esophageal dilatation is generally safe and effective with a low risk of complications.[18](B3)

The major problem with dilatation is the high recurrence rate, especially when used for the treatment of esophageal rings. Therapy with a PPI has been shown to decrease the risk of recurrence following dilatation of esophageal rings.[19] Recurrent symptomatic esophageal rings are treatable with repeat esophageal dilation followed by long-term acid suppression with a PPI. Alternative therapies exist for refractory esophageal rings that failed multiple dilatations. These include incisional therapy using electrocautery and laser division.[20][21](A1)

Differential Diagnosis

The differential diagnosis for esophageal webs and rings is extensive and includes other causes of dysphagia. History and evaluation by barium swallow and/or EGD can help identify those causes. Conditions that may mimic webs and rings include achalasia and esophageal strictures. Achalasia presents with progressive dysphagia to solids and liquids. The classic finding on barium swallow is distal dilatation of the esophagus with a “bird-beak” appearance.[22] Esophageal strictures present with progressive dysphagia to solids. They appear longer than webs and rings on barium swallow and have tapered ends.[23]

Prognosis

The prognosis of esophageal webs and rings is excellent because most patients are asymptomatic. Symptomatic webs and rings are treatable with esophageal dilatation which is safe and effective. The primary concern with therapy is the high recurrence rate following dilatation of esophageal rings. The risk of recurrence improves when using a PPI after dilatation.

Complications

Most esophageal webs and rings do not cause symptoms. Dysphagia occurs when webs and rings protrude into the esophageal lumen leading to luminal narrowing. If the luminal narrowing is severe enough, patients may develop food impaction with the inability to swallow food or even saliva.[16]