Background: Colorectal cancer (CRC) is often accompanied by increased excretion of hydrogen sulfide (H₂S). This study aimed to explore the value of exhaled H₂S in the diagnosis of CRC. Methods: A total of 80 people with normal colonoscopy results and 57 patients with CRC were enrolled into the present observational cohort study. Exhaled oral and nasal H₂S were detected by Nanocoulomb breath analyser. Results were compared between the two groups. Receiver operating characteristic (ROC) curves were analysed and area under the curves (AUCs) were calculated to assess the diagnostic value of exhaled H₂S. Meanwhile, the clinicopathological features, including gender, lesion location and tumour staging of patients with CRC, were also collected and analysed. Results: The amount of exhaled H₂S from patients with CRC was significantly higher than that of those with normal colonoscopy results. The ROC curve showed an AUC value of 0.73 and 0.71 based on oral and nasal H₂S detection, respectively. The exhaled H₂S in patients with CRC was correlated with gender, lesion location and tumour progression, including depth of invasion, lymphatic metastasis and TNM (Tumor, Lymph Nodes, Metastasis) staging. Conclusion: Exhaled H₂S analysis is a convenient and non-invasive detection method for diagnosing CRC, suggesting a potential role in population screening for CRC.

Purpose. Exhaled determination can detect metabolite hydrogen sulfide in the intestine. We aim to analyze the predictive value of hydrogen sulfide in the diagnosis of colorectal adenoma. Methods. We recruited seventy patients diagnosed with colorectal adenoma as the observation group and sixty-six healthy subjects as the control group. The colorectal adenoma was diagnosed by colonoscopy at the Endoscopy Center of Huashan Hospital affiliated to Fudan University from June 2018 to November 2019. Exhaled gas was collected through the nose and mouth, respectively, and hydrogen sulfide in exhaled gas was determined according to the manufacturers instructions. Results. Receiver operating characteristic (ROC) curve was analyzed based on the exhaled data of the observation group and the control group. The ROC curve showed an area under ROC curve (AUC) 0.724 for nasal exhaled H₂S, which had a diagnostic value. When nasal exhaled H₂S was >13.3 part per billion (ppb), the sensitivity and the specificity of predicting colorectal adenoma were 57 and 78, respectively. The exhaled H₂S of the observation group was significantly different from that of the control group. The AUC value was 0.716 as a prognostic factor of colorectal adenoma. As exhaled H₂S was >28.8ppb, the sensitivity and the specificity of predicting colorectal adenoma were 63 and 77, respectively. Conclusion. Exhaled and nasal H₂S determination has a predictive value for colorectal adenoma as a novel and noninvasive method. Therefore, it is worth conducting more research to analyze exhaled and nasal H₂S.

Background/Objectives. Stevens‐Johnson syndrome (SJS) is an allergic disease characterized by extensive epidermal detachment and mucositis. SJS involves both the skin and mucosal membranes, including the gastrointestinal tract. The present study is aimed at understanding the underlying reason of asymptomatic hyperamylasemia in patients with SJS, which may be associated with mucosal injury of the GI tract. Methods. A retrospective study on SJS patients was conducted at a tertiary medical center. All patients diagnosed as SJS, with available serum amylase index, were included. Clinical data of all subjects were retrospectively collected and analyzed. Colonic mucosal biopsies were obtained to measure tight junction protein expression. Results. A total of nine patients were included in the present study for study analysis. The average serum amylase of the study cohort was 228.78 ± 204.18 U/L. Among which, five patients had a positive fecal occult blood test (FOBT). Colonic mucosal biopsies were obtained and stained with occludin and zonula occludens‐1 (ZO‐1). The expression of occludin and ZO‐1 was significantly downregulated in SJS patients (p < 0.01), which was indicative of intestinal barrier dysfunction. Conclusion. Hyperamylasemia often extends beyond pancreatic diseases. Clinical awareness of asymptomatic hyperamylasemia secondary to other systemic diseases can help avoid unnecessary overexamination and overtreatment.