Inlet patch: prevalence, histologic type, and association with esophagitis, Barrett esophagus, and antritis

Inlet patch is a congenital anomaly of the cervical esophagus consisting of gastric mucosa. Case reports have documented the histologic type and its associated complications.

To report the prevalence and histologic types of inlet patch as well as its association with Barrett esophagus and Helicobacter pylori-associated gastritis.

We reviewed 1821 consecutive pathology reports from endoscopies of the upper gastrointestinal tract between 1995 and 2002 and identified 20 patients with inlet patch. The patients' ages ranged from 16 to 75 years (mean, 55 years). We examined biopsies from these patients of the cervical esophagus, distal esophagus, and antrum that had been stained with hematoxylin-eosin and the Steiner stain. Biopsies from the cervical esophagus composed of nonoxyntic gastric mucosa were also stained for gastrin-producing cells.

In our patient population, inlet patch occurred in 1.1% of all patients in whom an inlet patch had been searched for endoscopically and a biopsy performed. In the inlet patch, oxyntic mucosa was the most common histologic type (11/20), followed by cardiac mucosa (5/20). Four specimens of the inlet patch contained only foveolar epithelium and were therefore considered too superficial to be classified. Twelve of 20 biopsies of the inlet patch were inflamed, and 1 of them was associated with H pylori. Pancreatic acinar tissue was noted in 2 patients; no intestinal metaplasia was found. In the distal esophagus, 4 patients with inlet patch had distal esophagitis, 4 had Barrett esophagus, 5 had oxyntic mucosa, 3 had pancreatic acinar tissue (1 coexisting with oxyntic mucosa), and 5 presented with only unremarkable esophageal squamous mucosa. Antral gastritis was seen in 2 patients, 1 of them with H pylori. The same patient also had H pylori in the inlet patch.

Inlet patch occurred in about 1% of our study population. Oxyntic mucosa constituted the most common histologic type; inflammation was common. The H pylori infection of the inlet patch correlated with that of the antrum. None of the inlet patch biopsies showed intestinal metaplasia. Pancreatic acinar tissue occurred with similar frequency in the inlet patch and distal esophagus. Esophagitis was noted in 25% of the patients with inlet patch, and Barrett esophagus was noted in 20%.