Introduction: Calciphylaxis, also known as calcific uremic arteriolopathy (CUA), is a rare disease characterized by calcification, stenosis, and occlusion of arterioles and microvessels.The prognosis of calciphylaxis is extremely poor, with a usual survival time of less than 1 year.Thereby, early diagnosis is crucial.Typical clinical manifestations of calciphylaxis are concentrated in the skin, mainly presenting as ischemic manifestations.However, as a systemic vascular disease, involvement of visceral organs, especially the gastrointestinal tract, in calciphylaxis is rarely reported compared with skin involvement, which poses significant challenges to clinical diagnosis and treatment.Here, we present a case of calciphylaxis complicated by recurrent massive upper gastrointestinal bleeding, along with a review of the relevant literature on gastrointestinal involvement in calciphylaxis.Methods: A 56-year-old male (BMI 20.7 kg/m 2 ) was admitted in August 2024.His medical history began two years prior with increased nocturia.Laboratory tests at that time revealed significantly elevated serum creatinine (415.5 mol/L) and parathyroid hormone (PTH) levels (2469 pg/ml).16 months ago, his serum creatinine rose to 908 mol/L, and he began to receive maintenance hemodialysis.1 year ago, he developed recurrent massive melena without obvious inducement.After each episode of melena, his hemoglobin level dropped sharply from above 90 g/L to approximately 40 g/L.Gastroscopy identified hiatal hernia, chronic non-atrophic gastritis, and duodenal bulbitis, with no definitive bleeding lesion.Each episode was managed conservatively with fasting, acid suppression, and blood transfusion, leading to the cessation of bleeding and stabilization of hemoglobin.However, these massive melena episodes recurred every 1-3 months, totaling 5 episodes within one year.One week ago, he came to the outpatient clinic with severe right hand pain and cyanosis.His comorbidities included hypertension for over one year, which was well-controlled with regular medication.He had no history of warfarin use or diabetes.Physical examination revealed cyanosis of the right palm and multiple fingertips, with decreased local skin temperature.Key laboratory findings on admission included: hemoglobin 98 g/L, creatinine 390.6 mol/L (post-dialysis), calcium 2.81 mmol/L, phos-
Su et al. (Wed,) studied this question.