Solitary rectal ulcer syndrome (SRUS) is a rare benign disorder of the rectum strongly associated with chronic straining and rectal mucosal prolapse, which may be overt or occult. Its endoscopic appearance is highly variable, and atypical presentations can create significant diagnostic challenges, particularly in immunocompromised patients in whom infectious etiologies must be systematically excluded. We report a case of SRUS presenting as simultaneous contralateral kissing rectal ulcers in an HIV positive patient. Histopathology demonstrated the characteristic triad of fibromuscular obliteration of the lamina propria, smooth muscle extension between distorted crypts, and muscularis mucosae hypertrophy, establishing occult internal mucosal prolapse as the underlying mechanism. Comprehensive infectious evaluation including targeted testing for cytomegalovirus, herpes simplex virus, Neisseria gonorrhoeae, and Chlamydia trachomatis including lymphogranuloma venereum serovars was entirely negative. The patient achieved complete symptomatic resolution on conservative therapy with psyllium fiber supplementation at 2-month follow-up. This case illustrates an uncommon endoscopic presentation of SRUS, the diagnostic importance of histopathology in the absence of visible mucosal prolapse, and a systematic infectious exclusion approach in an HIV positive patient that may serve as a clinical reference for similar presentations.

Background and Study Aims Argon plasma coagulation (APC) is an established ablation technique, but limited by tangential probe orientation. ArgoCap was developed to allow precise, safe, and reproducible APC through visualizing the argon beam, shielding the probe, maintaining a defined distance, and enabling hybrid APC procedures. This study aimed to evaluate the clinical feasibility and safety of ArgoCap across multiple indications. Patients and Methods Between January 2022 and May 2025, 54 APC procedures using the ArgoCap were performed at three expert centers. Indications included Barrett's mucosa, ectopic gastric mucosa, gastric angioectasia, gastric antral vascular ectasia, radiation proctitis, and other indications. Primary endpoint was technical success, defined as access to the lesions and macroscopically complete ablation. Secondary endpoints included technical complications, adverse events, and procedural time. Results The majority of lesions were located in the esophagus (70%), followed by stomach (19%) and rectum (11%). Median lesion size was 13 mm (range 2-240 mm). Median ablation and procedure times were 8 min (2-15 min) and 25 min (8-75 min), respectively. Technical success was achieved in 47 cases (87%); subtotal ablation (>90% of the lesion) was possible in 52 cases (96%). Technical difficulties occurred in 1 case (2%); primary complication (ulceration with subsequent bleeding) was observed in 1 case (2%). Conclusions The ArgoCap enables easy and precise APC in the upper and lower gastrointestinal tract across multiple indications. It facilitates lesion access and visualization, reduces unintended mucosal contact, and allows hybrid APC procedures.

Rectal involvement in gastrointestinal tuberculosis (TB) is uncommon and may mimic inflammatory bowel disease or nonspecific proctitis, leading to diagnostic uncertainty. We report the case of an 18-year-old immunocompetent man presenting with chronic increased stool frequency and mucus passage, occasionally blood-streaked, without constitutional symptoms. Colonoscopy revealed nonspecific proctitis. Histopathological examination demonstrated confluent granulomas with Langhans giant cells. Microbiological confirmation including GeneXpert was negative. In view of the strongly suggestive histopathological findings and the endemic setting, a diagnosis of probable isolated TB was made, and anti-tubercular therapy was initiated. Probable rectal TB should be considered in the differential diagnosis of chronic proctitis, even in the absence of systemic features. Histopathology remains crucial, particularly in endemic regions where microbiological tests may be negative.

Takayasu arteritis (TAK) is a rare large-vessel vasculitis in children. A 14-year-old girl presented with intermittent fever, elevated inflammatory markers (C-reactive protein up to 117.63 mg/L and erythrocyte sedimentation rate of 93 mm/h), and computed tomography angiography demonstrating diffuse wall thickening of the aortic arch and its major branches. She had a previous diagnosis of ulcerative colitis; however, colonoscopy and biopsy revealed severe chronic active proctitis with glandular architectural irregularity and occasional cryptitis, but without crypt abscesses or granulomas, and the overall findings were insufficient to confirm ulcerative colitis or intestinal Behçet's disease. Behçet's disease was excluded because of the absence of oral or genital ulcers, ocular lesions, and skin manifestations. The patient met both the 2010 EULAR/PReS/PRINTO and 2022 ACR/EULAR classification criteria for TAK. Initial treatment with prednisone and adalimumab induced remission. A disease flare in June 2025 (C-reactive protein, 53.43 mg/L; erythrocyte sedimentation rate, 50 mm/h; and worsening carotid artery wall thickening) was controlled by increasing the prednisone dose and adding tocilizumab. At the 10-month follow-up, she remained asymptomatic, with stable vascular findings. This case highlights the importance of applying rigorous diagnostic criteria to avoid overdiagnosis of Behçet's disease in children with TAK and nonspecific intestinal inflammation.

Mpox (monkeypox) is an emerging viral infection with a broad and evolving clinical spectrum that increasingly spans beyond its characteristic cutaneous manifestations. Anorectal manifestations are well recognized in patients with Mpox in recent outbreaks. However, the gastrointestinal (GI) or anorectal symptoms may precede the typical rash, creating significant diagnostic challenges and delaying appropriate infection control measures. We describe a quinquagenarian man with poorly controlled diabetes mellitus who presented with fever, diarrhea, tenesmus, and severe perianal pain. Cross-sectional imaging demonstrated diffuse rectosigmoid inflammation, while endoscopy revealed severe ulcerative proctitis. Initial evaluation favored acute infectious proctitis, and treatment was directed accordingly. However, the subsequent development of disseminated pustular skin lesions prompted consideration of Mpox, which was ultimately confirmed by polymerase chain reaction testing of the lesions. Extensive testing excluded concurrent human immunodeficiency virus (HIV) infection and other common sexually transmitted infections, and rectal biopsy demonstrated nonspecific acute colitis. The patient recovered with supportive management and had complete endoscopic resolution on follow-up colonoscopy. This case illustrates the relevance of considering Mpox in the differential diagnosis of acute proctitis and lower GI symptoms, even before characteristic skin lesions appear. It also underscores the diagnostic value of maintaining a high index of suspicion in patients presenting with severe anorectal disease and points out that diabetes-associated immune dysfunction may play a role in such cases. Early recognition of atypical GI manifestations is essential for timely diagnosis, appropriate patient isolation, avoidance of unnecessary interventions, and optimal clinical outcomes.