Equine multisystemic eosinophilic epitheliotropic disease in two horses in Italy

Abstract

Summary Equine multisystemic eosinophilic epitheliotropic disease (EMEED) is a rare condition characterised by eosinophilic infiltration of multiple organs. The aim of the present work was to describe two clinical cases that occurred in Italy, where no previous EMEED cases have been reported. A 2‐year‐old Standardbred colt was referred for poor body condition, multiple oral ulcerations, ventral and limb oedema, nasal discharge and coughing. Relative eosinophilia, increased ALP, GGT, LDH and hypoalbuminaemia were detected. Abdominal ultrasonography showed hepatomegaly and hepatic biopsy revealed eosinophilic hepatitis. After euthanasia, post‐mortem examination revealed eosinophilic infiltration and fibrosis of intestinal wall, liver, pancreas and mesenteric lymph nodes. The second case was a 13‐year‐old pony hospitalised for acute respiratory distress, poor body condition, nasal discharge, cough and dyspnoea. Leucocytosis with relative eosinophilia was detected. Thoracic ultrasonography showed disseminated comet tail artefacts. Endoscopy of the airways revealed disseminated white nodules in the nasal cavities and nasopharynx; biopsy showed eosinophilic infiltrates. After euthanasia, post‐mortem examination revealed eosinophilic infiltration of intestinal wall, liver, mediastinal lymph nodes, lungs and kidneys. Both patients presented with poor body condition, which is the most common sign of EMEED. They also showed nasal discharge, and the second case showed respiratory distress and disseminated white nodules, which have not been reported previously. In both cases, liver involvement was observed. Post‐mortem examination provided the most specific findings, such as lymphadenomegaly and eosinophilic infiltration of multiple organs. Although weight loss remains the main sign of EMEED, liver and airway evaluation was extremely useful for the diagnosis in these cases.

Multisystemic eosinophilic epitheliotropic disease in a horse

“…Multisystemic eosinophilic epitheliotropic disease is an uncommon disease in horses that can be difficult to diagnose ante-mortem due to its unpredictable multi-organ involvement (5,6). The etiology for this condition is not yet fully established (1,3,5).…”

“…Clinical presentations of MEED, depending on organ infiltration, can vary widely. Documented cases with this disease have most reliably shown signs of chronic weight loss and frequent dermatologic abnormalities (1,3,5,6,7). Inconsistent features include pyrexia, respiratory distress, pancreatitis, coronitis, hepatitis, recurrent colic, oral ulceration, and a change in appetite (1,6,7).…”

“…The diagnosis of multisystemic eosinophilic epitheliotropic disease (MEED) relies on a process of exclusion (1,6). In this case, no identifiable etiologic agent was found on histologic examination, therefore reducing the suspicion of Pythium insidiosum, Habronema sp.…”

Molecular immunology and genomics: The future of multisystemic eosinophilic epitheliotropic disease

“…In this issue of Equine Veterinary Education , Stucchi et al. (2022) present two cases of MEED believed to be the first identified in Italy. These cases bring attention to some commonly reported characteristics of EADs, and MEED in particular, including a relatively recent appearance in the literature, lack of an identifiable underlying aetiology, limited treatment options, and often poor prognosis for complete resolution.…”

“…Stucchi et al. (2022) point out the low number of MEED cases reported overall and emphasise that theirs are the first documented cases in Italy. Equine eosinophilic enteritis was referred to as an “emerging disease” in 2006 (Archer et al., 2006), and eosinophilic keratitis was similarly described in 2018 (Gonzalez‐Medina, 2019).…”