Abstract

The objective of this study was to report a possible hereditary condition of Exercise-Induced Pulmonary Hemorrhage, collapse and sudden death detected in English Thoroughbred horses in Venezuela. Results case 1: Necropsy was performed on a 2-year-old English Thoroughbred horse (2006), with epistaxis, collapse in training and sudden death with severe massive hemothorax, rupture of the segmental bronchial arteries, with edema, pulmonary congestion and petechial hemorrhage, to confluent ecchymotic and subserosal petechial hemorrhages were observed in the dorsocaudal pulmonary lobes. Histopathological lesions showed severe congestion, marked interstitial edema, and acute pulmonary hemorrhage due to rupture of focal bronchial arterioles by vascular rhexis. Case 2: Necropsy was performed on a 2-year-old Thoroughbred horse (2008), with epistaxis, collapse in the race and sudden death with severe massive hemothorax, rupture of the segmental bronchial arteries, with edema, pulmonary congestion and confluent petechial to ecchymotic hemorrhage, subserosal petechial hemorrhages were observed in the dorsocaudal pulmonary lobes. Histopathological lesions of the lungs showed severe congestion, marked interstitial edema and acute pulmonary hemorrhage due to rupture of focal bronchial arterioles, hemorrhage due to vascular rhexis. In the review of the pedigree in both cases the mother and maternal grandfather coincided, in two different stallions in 2006 and in 2008. The kinship tests by DNA study confirmed the kinship. In conclusion, the clinical history, macroscopic and histopathological presentation were compatible with a diagnosis of bilateral epistaxis, collapse and sudden death associated with exercise-induced pulmonary hemorrhage, a possible hereditary condition confirmed by the parentage study.

Keywords: Epistaxis; EIPH; Hereditary; Sudden

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