Concurrent atypical myopathy and equine dysautonomia in two horses.

Authors: Vercauteren G, van der Heyden S, Lefère L, Chiers K, Laevens H, Ducatelle R

Journal: Equine veterinary journal

DOI: 10.2746/042516407x206409 PubMed: 17910273Log in to save

Summary

# Editorial Summary: Concurrent Atypical Myopathy and Equine Dysautonomia Two horses presenting simultaneously with clinical and pathological features of both atypical myopathy (AM) and equine grass sickness (EGS) prompted Vercauteren and colleagues to investigate whether these typically separate conditions might share underlying predisposing factors. Rather than proposing a unified aetiological mechanism, the authors documented detailed clinical presentations and post-mortem lesions in both animals, establishing that concurrent disease was unlikely to represent mere coincidence given the rarity of each condition individually. The findings suggest that whilst AM and EGS remain distinct entities with different pathophysiological mechanisms, certain environmental or constitutional risk factors may render affected horses susceptible to both conditions simultaneously—a consideration that warrants investigation in future epidemiological studies. For practitioners managing horses with suspected myopathy or dysautonomia, this case series underscores the importance of thorough diagnostic workup to detect concurrent disease and highlights the potential value of examining shared risk factors (such as pasture composition, toxin exposure, or metabolic predisposition) when encountering either condition in a clinical setting.

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Practical Takeaways

•When diagnosing atypical myopathy or equine grass sickness, consider screening for concurrent disease as these conditions may share common predisposing factors
•The concurrent presentation of these rare diseases warrants investigation into shared environmental or nutritional risk factors on affected premises
•Clinical assessment should be thorough as horses may present with overlapping signs from multiple conditions

Key Findings

•Two horses presented with concurrent clinical signs of both atypical myopathy and equine grass sickness
•Concurrent presentation of two rare diseases in the same animals suggests common predisposing causes rather than coincidence
•Pathological lesions consistent with both conditions were identified in affected horses

Conditions Studied

atypical myopathyequine grass sicknessequine dysautonomia

Related References

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