Aucun.

Aucune.

None.

BACKGROUND: Sterile granuloma/pyogranuloma syndrome (SGPS) is an immune-mediated disease producing nodular and plaque-like skin lesions in dogs. Ocular involvement has been reported mainly in periocular skin and eyelids, with no histologically documented conjunctival lesions. This report describes a palpebral conjunctival nodule in a dog with SGPS and its distinction from nodular ocular surface diseases such as nodular granulomatous episcleritis and other differential diagnoses. CASE PRESENTATION: A 3-year-10-month-old Polish Tatra Dog presented with mucopurulent discharge, hyperaemia of the bulbar, palpebral, and third-eyelid conjunctivae, a firm 1 cm nodule on the right lower palpebral conjunctiva, and medial eyelid thickening with ectropion. Three months earlier, multiple cutaneous nodules had been diagnosed as SGPS. Topical and systemic corticosteroid therapy improved the skin lesions but neither the conjunctival mass nor the eyelid thickening, necessitating surgical excision of the nodule. In contrast, the eyelid thickening resolved during a subsequent prednisone taper, and no recurrence was observed over 20 months. Histopathology revealed a well-demarcated conjunctival stromal nodule with deep extension into the palpebral stroma, surrounding blood vessels, peripheral nerves, and the orbicularis oculi muscle. The infiltrate consisted of CD3⁺ T cells, CD20⁺/CD79⁺ B cells, plasma cells, MAC387-positive macrophages, and scattered Iba1-positive histiocytes, with small neutrophilic foci and no epithelioid cells, multinucleated giant cells, mitotic figures, or foreign material. CONCLUSION: This case represents the first histopathologically confirmed conjunctival manifestation of SGPS. Its conjunctival origin and mixed lymphocytic-histiocytic profile expand the recognized spectrum of SGPS and support including SGPS in the differential diagnosis for well-circumscribed conjunctival nodules. Surgical excision may be required when such lesions do not regress or cause mechanical dysfunction.