AIM: To investigate clinical, endoscopic and pathological characteristics of drug-induced esophagitis. METHODS: Data for patients diagnosed with drug-induced esophagitis from April 2002 to May 2013 was reviewed. Patients diagnosed with malignancy, viral or fungal esophagitis were excluded. Clinical, endoscopic and pathological characteristics of patients diagnosed with drug-induced esophagitis were analyzed. RESULTS: Seventy-eight patients were diagnosed with drug-induced esophagitis. Their mean age was 43.9 ± 18.9 years and 35.9% were male. Common symptoms were chest pain (71.8%), odynophagia (38.5%) and dysphagia (29.5%). The endoscopic location was in the middle third of esophagus in 78.2%. Endoscopic findings were ulcer (82.1%), erosion (17.9%), ulcer with bleeding (24.4%), coating with drug material (5.1%), impacted pill fragments (3.8%) and stricture (2.6%). Kissing ulcers were observed in 43.6%. The main causative agents were antibiotics and non-steroidal anti-inflammatory drugs. All the patients were treated with proton pump inhibitors (PPIs) or sucralfate, and the causative drugs were discontinued. Nineteen patients with drug-induced esophagitis were followed up with endoscopy and revealed normal findings, scars or healing ulcers. CONCLUSION: Drug-induced esophagitis mainly presents as chest pain, odynophagia and dysphagia, and may be successfully treated with PPIs and discontinuation of the causative drug. Kissing ulcers were observed in 43.6%.

Unregulated activation of nuclear factor-κB (NF-κB) plays a critical role in the pathogenesis of Crohn’s disease. In this study, we investigated the clinical characteristics and disease outcome of Crohn’s disease patients with varying levels of the NF-κB activation. Crohn’s disease patients who underwent surgical bowel resection were divided into two groups, based on the activation status of NF-κB. NF-κB activation was assessed by the immunoreactivity of nuclear NF-κB during immunohistochemical staining of bowel resection specimens. We compared the demographic, clinical and histologic characteristics between groups. Furthermore, the occurrence of reoperation, readmission, and medication change due to disease flare-up were investigated according to NF-κB activation status. Among 83 Crohn’s disease patients, 47 (56%) showed high NF-κB activity and 36 (44%) showed low NF-κB activity. Patients with high NF-κB activity had higher frequency of ileocolonic involvement (P = 0.028) and lower frequency of perianal involvement (P = 0.042) relative to those with low NF-κB activity. Total histologic scores were significantly higher in patients with high NF-κB activity than those with low NF-κB activity (P = 0.044). There was no significant difference in the frequency of reoperation, readmission, and medication change in relation to NF-κB activation status. Crohn’s disease patients with high NF-κB activation showed specific clinical manifestations of higher frequency of ileocolonic involvement and lower frequency of perianal involvement relative to those with low NF-κB activation. High NF-κB activity was associated with higher histologic scores. However, the NF-κB activity did not affect the outcome and disease course after surgery.

Periostin is a matricellular protein that interacts with various integrin molecules on the cell surface. Although periostin is expressed in inflamed colonic mucosa, its role in the regulation of intestinal inflammation remains unclear. We investigated the role of periostin in intestinal inflammation using Postn-deficient (Postn^-/-) mice. Intestinal epithelial cells (IECs) were transfected by Postn small interfering RNAs. Periostin expression was determined in colon tissue samples from ulcerative colitis (UC) patients. Oral administration of dextran sulfate sodium (DSS) or rectal administration of trinitrobenzene sulfonic acid, induced severe colitis in wild-type mice, but not in Postn^-/- mice. Administration of recombinant periostin induced colitis in Postn^-/- mice. The periostin neutralizing-antibody ameliorated the severity of colitis in DSS-treated wild-type mice. Silencing of Postn inhibited inteleukin (IL)-8 mRNA expression and NF-κB DNA-binding activity in IECs. Tumor necrosis factor (TNF)-α upregulated mRNA expression of Postn in IECs, and recombinant periostin strongly enhanced IL-8 expression in combination with TNF-α, which was suppressed by an antibody against integrin α_v (CD51). Periostin and CD51 were expressed at significantly higher levels in UC patients than in controls. Periostin mediates intestinal inflammation through the activation of NF-κB signaling, which suggests that periostin is a potential therapeutic target for inflammatory bowel disease.

Clinical significance of CT-defined minimal ascites in patients with gastric cancer