DOI: https://doi.org/10.36347/sjmcr.2025.v13i11.007

Pages: 2683-2686

Background: Kaposi sarcoma (KS) is an HIV‑defining vascular tumor that may initially present in the oral cavity and mimic other vascular lesions, making biopsy essential for diagnosis. Case presentation: A 47-year-old man presented with a 1-month history of a progressively enlarging red nodule on the right buccal mucosa. Clinical examination revealed multiple painless angiomatous papules on the right vestibule. One month later, lesions had spread, becoming diffuse bluish-violaceous nodules on the oral mucosa, associated with cervical and inguinal lymphadenopathy, violaceous skin plaques on the limbs and trunk, and chronic diarrhea. Oral biopsy suggested vascular proliferation, while skin biopsy confirmed Kaposi sarcoma. HIV serology was positive, establishing HIV-associated KS. Combination antiretroviral therapy was initiated, with additional local or systemic treatment considered according to disease burden Discussion: Oral KS can progress from flat, asymptomatic red‑to‑purple lesions to papules and nodules that may ulcerate or bleed and impair oral function; the palate, gingiva, and tongue are commonly affected, with buccal mucosa and vestibule involvement less frequent but observed in this case. Differential diagnoses include bacillary angiomatosis, hemangioma, pyogenic granuloma, inflammatory or drug‑induced gingival enlargement, melanoma, lymphoma, and leukemia. Conclusion: Early recognition of atypical oral vascular lesions can expedite HIV testing and treatment initiation in HIV‑associated KS.