Clinical and genetic characteristics of Chinese patients diagnosed with chronic enteropathy associated with SLCO2A1 gene

Background and aims Chronic enteropathy associated with SLCO2A1 gene is a rare intestinal disease caused by loss-of-function SLCO2A1 mutations, with clinical and genetic characteristics remaining largely unknown, especially in Chinese patients. This study aims to reveal clinical and genetic features of Chinese CEAS patients, highlighting the previously unreported or unemphasized characteristics. Methods We enrolled 12 Chinese patients with chronic enteropathy associated with SLCO2A1 gene admitted to Peking Union Medical College Hospital from January 2018 to December 2022. Clinical and genetic data of these patients were collected and analyzed. Results 58.3% of patients were male, who also had primary hypertrophic osteoarthropathy, whereas female patients did not have primary hypertrophic osteoarthropathy. Apart from common symptoms associated with anemia and hypoalbuminemia, abdominal pain, ileus, diarrhea, and hematochezia were present. 4 of the 5 female patients had early-onset amenorrhea, though the causal relationship remained to be clarified. Endoscopy and computed tomography enterography revealed that lesions can occur in any part of the digestive tract, most commonly in the ileum. Pathology showed multiple superficial ulcers with adjacent vascular dilatation, and loss of SLCO2A1 expression, particularly in gastrointestinal vascular endothelial cells. Genetic analysis confirmed SLCO2A1 mutations in all patients and identified 11 new SLCO2A1 variants for CEAS. Conclusions This study reports new clinical, pathological, and genetic findings in 12 Chinese patients with chronic enteropathy associated with SLCO2A1 gene. This study provides insights into the pathogenesis of this disease. However, studies with larger sample sizes and more in-depth mechanism research are still required.