Assessing the performance of a new diagnostic criterion for diagnosing esophageal lichen planus.

Esophageal lichen planus (ELP) is a unique manifestation of lichen planus that is rarely studied. This disorder presents diagnostic challenges due to variable clinical presentations and the absence of universally accepted diagnostic criteria. This study evaluates the performance of the Schauer Diagnostic Criteria (SDC) in diagnosing ELP for two specific cohorts: patients with extra-esophageal manifestations of lichen planus (LP) and patients without extra-esophageal manifestations of LP. We analyzed esophageal biopsies with lichenoid patterns from a tertiary care center. We calculated the SDC scores using endoscopy and pathology reports in patients with extra-esophageal LP (17 patients, 43 specimens) and patients without extra-esophageal lichen planus (60 patients, 84 specimens). We then reviewed gastroenterology clinic notes for these patients to assess the performance of the SDC in correctly diagnosing ELP for these cohorts. The SDC demonstrated high concordance with gastroenterologists in diagnosing ELP in patients with extra-esophageal LP. Meanwhile, the SDC had higher discordance with gastroenterologists for patients without any extra-esophageal LP, suggesting that ELP is likely underdiagnosed clinically for this cohort of patients. Key endoscopic findings included mucosal pallor and sloughing, while histologically, lymphocytic infiltration and dyskeratosis were common across all specimens. Our findings support the utility of SDC in both patient cohorts. Our study validates the SDC for the study's original patient population: patients with prior extra-esophageal lichen planus. In patients without prior extra-esophageal lichen planus, our study demonstrates the utility of SDC and points to some potential missed or delayed diagnoses. For patients with high suspicion, widespread use of this diagnostic tool could standardize the diagnosis of this under-recognized condition.