A retrospective study of cutaneous equine sarcoidosis and its potential infectious aetiological agents.

The research article discusses a study about a skin condition in horses known as equine sarcoidosis, where the cause of the disease and treatment options were investigated. The research found that although the skin disease can be fatal in horses, it does not appear to be caused by microbial pathogens and can be managed with glucocorticoid therapy in surviving horses.

Study Overview

• The research was a retrospective study that investigated cases of equine sarcoidosis (ES) over an 18-year period. This is a skin condition that affects horses, and in some instances, it also impacts the lungs and other organs.
• The study involved nine horses ranging from 5 to 21 years old that were diagnosed with ES.
• Thoroughbreds and geldings were noted to be particularly predisposed to the condition.

Observations and Findings

• The symptoms identified included skin lesions, crusts, scales, hair loss, and itchiness. These were most commonly found on the legs, thighs, elbows, thorax, neck, face, and the lower portion of the abdomen.
• Within the sample group, three horses were euthanized immediately after being admitted to the hospital, while others were able to survive for up to 12 years with the condition.

Investigation into Cause

• The researchers conducted various tests on cutaneous samples from eight of the horses to investigate potential causal agents. They looked for the presence of various microbes, including Mycobacterium spp., Coccidioides immitis, Cryptococcus neoformans, Corynebacterium pseudotuberculosis, and Borrelia burgdorferi.
• All tests returned negative results, which led to the conclusion that ES is unlikely to be caused by microbial pathogens.
• As such, ES continues to be a diagnosis of exclusion, meaning it is only diagnosed when other potential conditions have been ruled out.

Treatment Response

• The research noted that when ES is limited to the skin, it has a good prognosis.
• All of the surviving horses showed either a partial or complete response to glucocorticoid therapy, which is a type of treatment involving steroids to reduce inflammation.