A prospective study of the association of anemia and thrombocytopenia with ocular lesions in dogs Michal Shelah-Goraly a , Itamar Aroch a , Philip H. Kass b , Yaron Bruchim a , Ron Ofri a, * a Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot 76100, Israel b Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA Accepted 27 May 2008 Abstract This prospective study was conducted to evaluate the prevalence and severity of ocular lesions in dogs with anemia (packed cell vol- ume 6 20%) and/or thrombocytopenia (platelet count < 150,000/lL). Dogs were divided into four groups: (1) anemic (n = 17); (2) thrombocytopenic (n = 36); (3) anemic and thrombocytopenic (n = 24); and (4) healthy controls (n = 26). The prevalence of ophthalmic lesions in these four groups was 12%, 42%, 42% and 0%, respectively. Anemia was not associated with the presence of ocular lesions (P = 0.41) or their severity. Thrombocytopenia was significantly associated with the presence of ocular lesions (P = 0.0016) and with their severity (P = 0.017). We conclude that thrombocytopenia, but not anemia, is associated with ocular lesions in dogs. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Canine; Hematology; Hyphema; Retinal detachment; Retinal hemorrhage; Platelets Introduction Anemia and thrombocytopenia are both very common canine hematological abnormalities. Anemia occurs so fre- quently that a complete blood cell count (CBC) is generally requested in the diagnostic assessment of any ill dog. It is a clinical and laboratory sign and not a disease, resulting from numerous different primary conditions and diseases (Feldman, 2005; Giger, 2005). Quantitative platelet defects are also common in dogs and thrombocytopenia is the most common acquired canine hemostatic defect (Feldman et al., 1988; Brooks and Catalfamo, 2005). It has been detected in 10% of canine patients with neoplasia (Grindem et al., 1994) and in 5.2% of more than 18,000 canine cases admitted to a veterinary hospital (Grindem et al., 1991). The most common etiologies of thrombocytopenia in the latter study were inflammatory and infectious causes (59%), neoplasia (23%) and immune-mediated thrombocy- topenia (5%) (Grindem et al., 1991). In humans, anemia and thrombocytopenia are fre- quently reported as causes of retinal hemorrhage and other ocular lesions (Guyer et al., 1989; abu el-Asrar et al., 1996; Carraro et al., 2001). A similar association is suspected in the veterinary literature, as ocular lesions have been reported in various conditions manifested by anemia and/ or thrombocytopenia in dogs, including infectious diseases such as canine monocytic ehrlichiosis (CME) (Komnenou et al., 2007) and leishmaniasis (Pen ˜ a et al., 2000), neoplastic diseases such as lymphoma (Krohne et al., 1994) and drug toxicity (Giger et al., 1985). However, in all these previous studies the ocular lesions were described as manifestations of the primary disease, and were not evaluated as compli- cations with relation to the hematological abnormalities. To the best of our knowledge, no study has been conducted to directly study ocular lesions in dogs with anemia and/or thrombocytopenia as the ‘exposure’ variables. This study aimed to prospectively assess and characterize the preva- lence and association of ocular lesions with anemia and 1090-0233/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.tvjl.2008.05.027 * Corresponding author. Tel.: +972 5 48820523; fax: +972 3 9604079. E-mail address: ofri@agri.huji.ac.il (R. Ofri). www.elsevier.com/locate/tvjl Available online at www.sciencedirect.com The Veterinary Journal xxx (2008) xxx–xxx The Veterinary Journal ARTICLE IN PRESS Please cite this article in press as: Shelah-Goraly, M., et al., A prospective study of the association of anemia and ..., The Veterinary Journal (2008), doi:10.1016/j.tvjl.2008.05.027