Background. Canine granulomatous scleritis is an uncommon disease that can be classified as necrotizing or non-necrotizing. Clinical signs associated with scleritis are typically severe, resulting in pain and loss of vision, and response to treatment is often poor. Necrotizing scleritis has been previously associated with scleral rupture. Case Presentation. A 10-year-old male castrated Chihuahua was presented for periocular pain, tissue swelling adjacent to the limbus superiorly, chemosis, mild corneal edema and neovascularization adjacent to the superotemporal limbus in the right eye. The left eye was within clinically normal limits. Surgical exploration of the right eye revealed a scleral rupture at the inferonasal aspect of the globe. Histopathology revealed a non-necrotizing granulomatous scleritis with no infectious organisms visualized. Infectious disease testing and special histopathologic staining did not reveal an underlying infectious etiology. Conclusion. Granulomatous scleritis is a painful and vision-threatening disease that needs to be treated early and aggressively in order to avoid loss of vision or loss of the eye. Globe rupture secondary to severe non-necrotizing scleritis is an uncommon, but detrimental, clinical manifestation of this disease. This is the first case report of scleral rupture secondary to severe non-necrotizing scleritis and therefore represents a unique and interesting disease manifestation. 1. Background Scleritis is an uncommon and poorly understood disease process in dogs [1]. The sclera comprises approximately 80% of the fibrous outer portion of the eye and is the posterior continuation of the transparent cornea. The sclera is closely associated with several ocular tissues and for this reason secondary keratitis, conjunctivitis, chorioretinitis, orbital cellulitis, and blepharitis may be seen in cases of primary scleritis [2]. The etiology of canine scleritis is often presumed to be immune-mediated due to the characteristic presence of granulomatous inflammatory infiltrates, response to immunosuppressive therapy, and inability to identify microorganisms by histopathology [3]. Other potential underlying causes of scleritis include Ehrlichia canis, Onchocerca spp., Toxoplasma gondii, trauma (including surgical trauma), and extension of panophthalmitis or orbital cellulitis [1, 3, 4]. In humans, granulomatous scleritis is often associated with systemic vascular or autoimmune collagen disorders including rheumatoid arthritis [5], Wegener’s granulomatosis [6], and systemic lupus erythematosus [7]. Some reported cases
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