Arenas-Martínez, Josealberto S.

Abstract Topic Benign Disease: Eosinophilic Esophagitis Background Active inflammation in eosinophilic esophagitis (EoE) disrupts the mucosal barrier, leading to dilated intercellular spaces and decreased transepithelial electrical resistance. Mucosal impedance (MI) has been used to assess mucosal integrity in EoE. We evaluated whether baseline MI measured by high-resolution impedance manometry (HRIM) distinguishes active and inactive EoE. Methods We retrospectively reviewed data from patients with EoE who underwent endoscopic esophageal biopsies within three months of HRIM from 2018-2026 at our tertiary referral center and had no treatment changes between studies. We excluded patients with a history of foregut surgery, erosive esophagitis, or Barrett’s esophagus. Demographics, endoscopy and pathology results were collected by chart review. Active EoE was histologically defined as ≥15 eosinophils per high-power field. Esophageal baseline MI was measured in the 30-second landmark period for the whole esophagus (from 2 cm above LES to 2 cm below UES), distal esophagus (from 2–7 cm above LES), and mid/proximal esophagus (from 10 cm above LES to 2 cm below UES). Mann–Whitney U or T tests were used for comparisons . Optimal MI thresholds were identified by Youden index with 10,000 bootstrap validations, and interrater reliability was assessed using two-way mixed effects intraclass correlation coefficients. Results Seventy-three patients were included: 37 (51%) female, median age 52 years, median BMI 27.2 kg/m2. Fifty-seven patients (78%) had atopic history, including seasonal allergies (38, 52%), asthma (31, 42%), eczema (21, 29%), and food allergies (19, 26%). Thirty-nine patients (53%) were receiving proton pump inhibitors, 25 (34%) were not on EoE therapy, 5 (6.8%) were on swallowed topical steroids, 3 (4.1%) were on dupilumab, and 1 (1.4%) was on an elimination diet. Esophageal strictures were present in 23 patients (32%), and 45 (62%) had active EoE. Baseline MI measurement showed high interrater reliability (n=50, 2 raters; intraclass correlation coefficient 0.937–0.963, p<0.001). Basal mean and minimal impedance were significantly lower in active EoE across all segments, greatest in the distal esophagus (all p<0.05; Figure 1). ROC analysis showed high discrimination of distal mean MI, with a cutoff ≤1.91 kΩ (AUC=0.837, sensitivity 67.9%, specificity 86.7%, Youden 0.545; Figure 2). Conclusion Baseline mucosal impedance during HRIM distinguishes active from inactive EoE, with strongest discrimination in the distal esophagus, supporting MI as a potential, minimally-invasive physiologic marker of mucosal inflammation and disease activity. Clinically, MI may serve as an adjunct tool in dysphagia evaluation, prompting EoE-directed biopsy when abnormal, aiding management in biopsy–symptom discordance, and potentially supporting disease monitoring in selected patients. Larger prospective studies are warranted.

Abstract Topic Benign Disease: Other Background Lichen planus is a chronic immune-mediated skin disease that may involve the esophagus. Esophageal lichen planus (ELP) is considered rare, but likely underdiagnosed. Lack of published guidelines for ELP results in significant treatment variability. Given heterogeneous practice patterns and emerging treatments, further outcome data are needed. Methods A retrospective cohort of ELP patients was assembled from 3 academic centers. Patients ≥ 18 years old were identified by ICD10 code search (L43.8) in the electronic health record, from 2006 to 2025. Patients were included if they had initial endoscopy, histology, and follow-up endoscopy showing features of LP, and excluded if there was diagnostic uncertainty, unavailable procedural documentation, or other esophageal diseases. Endoscopic findings were assessed qualitatively by manual review of reports. Data abstracted included demographics, presenting symptoms, endoscopic/histologic findings, treatment, and clinical outcomes. Statistical analysis was performed in R. Results 193 patients met inclusion criteria. Mean age at index endoscopy was 65 years, 86% were female, 98% were non-Hispanic Caucasian, 39% were ever smokers, and mean BMI was 26. Dysphagia was the most common presenting symptom (90%). Strictures were common (73%), 58% underwent dilation during initial endoscopy. Endoscopic findings included presence of sloughing (20%), exudate (22%) and friability (23%). Histology showed lymphocytic infiltrate (47%), parakeratosis/dyskeratosis (42%) and Civatte bodies (17%). Topical steroids (71%) and PPIs (63%) were used most frequently for treatment. Immunosuppressives (tacrolimus, systemic steroids, mycophenolate, methotrexate, hydroxychloroquine, cyclosporine, azathioprine, JAK inhibitor) were used in 54% of patients. Endoscopic improvement was seen in 66%, with highest response rates in tacrolimus (100%), hydroxychloroquine (100%), and a JAK inhibitor (100%). Symptom improvement was seen in 63%, with the greatest benefit seen in patients treated with a JAK inhibitor (100%) and hydroxychloroquine (86%). Conclusion In this large, multisite cohort, ELP demonstrated significant morbidity, with high rates of dysphagia, strictures, and inflammatory changes. Dilation appeared to be safe, with only a single iatrogenic perforation identified. Esophageal squamous cell cancer risk was low but present, at 4%. Despite heterogeneous treatment practices, several therapies – tacrolimus, hydroxychloroquine, and JAK inhibitors – were associated with marked endoscopic and symptomatic improvement. Prospective studies are needed to clarify the optimal approach to pharmacological management of ELP.