TDK conference 2021

Eosinophilic keratoconjunctivitis (EKC) is an immune-mediated disease of the cornea and conjunctiva of the equine eye when eosinophil granulocytes migrate on the corneal and/or conjunctival surface. During the degranulation of these cells, toxic proteins are released which damage the epithelial cells of the cornea and conjunctiva. Although the exact aetiology and pathogenesis is still unknown, an underlying type IV hypersensitivity reaction is highly suspected. The aim of the study was to analyse the clinical records of 114 horses diagnosed with EKC between 2012 and 2021 at Tierärztliche Klinik für Pferde Domäne Karthaus in Dülmen, Germany. Analysed data included age, breed, gender, the year and month of admission, the affected part of the eye, the uni- or bilateral nature of the disease, available laboratory results, the presence of secondary infections, recovery time, and recurrences. Descriptive statistics were done. Minimum, maximum, and mean age of presentation was 1, 22 and 11.5 years, respectively. Warmbloods were overrepresented (78.9%). The population consisted of 51 mares (44.7%), 9 stallions (7.9%) and 54 geldings (47.4%). The disease shows seasonality, the highest number of cases were diagnosed in July, August, and September. The cornea was affected alone or in combination with the conjunctiva in 85.1% of the horses. Lesions only on the conjunctiva were found in 14.9% of the horses. The disease was bilateral in 43% of the animals. Minimum, maximum, and median recovery time was 5, 330, and 30 days, respectively. The affected eye was surgically removed in 8 horses (7%). Recurrence rate was very low, it occurred in two horses (1.8%). To our knowledge, the current study population is the largest in the literature, thus our results may provide a deeper insight into this ocular condition to better understand its clinical features.