Hypertrophic Osteoarthropathy a Rare Extra-intestinal Manifestation in a Case of Non-Specific Colitis: A Case Report

ABSTRACT: Background: Hypertrophic osteoarthropathy (HOA) is an uncommon syndrome characterized by digital clubbing, periostitis of long bones, and arthralgia or joint swelling. While it is most frequently associated with pulmonary diseases particularly bronchogenic carcinoma1, cystic fibrosis1, and chronic lung infections it can also occur in non-pulmonary systemic conditions. Gastrointestinal associations are rare, with most cases reported in longstanding inflammatory bowel disease2 (IBD), such as Crohn’s disease or ulcerative colitis5. The occurrence of HOA in the context of non-specific colitis, particularly as an early or presenting feature, is exceedingly rare. Case Summary: We report a case of 31-year-old man, presented with progressive joints pain and digital clubbing, without cardio-respiratory symptoms. Imaging confirmed periosteosis suggestive of hypertrophic osteoarthropathy. Comprehensive pulmonary and oncologic evaluations were unremarkable. Gastrointestinal workup, initiated in response to mild but persistent abdominal discomfort and altered bowel habits, revealed patchy colonic mucosal inflammation. Histopathology confirmed the diagnosis of non-specific colitis, without features of Crohn’s disease or ulcerative colitis. The patient responded to NSAIDs and mesalazine, with partial resolution of musculoskeletal symptoms. Conclusion: This case highlights the potential for non-specific colitis to manifest with systemic complications such as HOA, even before classic gastrointestinal features become apparent. Clinicians should maintain a high index of suspicion for atypical presentations of HOA and consider gastrointestinal sources when common cardio- pulmonary causes are excluded. Early diagnosis can lead to appropriate management and prevent unnecessary delays in treatment. Keywords: Hypertrophic osteoarthropathy, Periosteosis, Colitis, Clubbing, Extra-intestinal