Equine pastern dermatitis: a narrative review on clinical presentation, diagnosis, risk factors, prevention, and therapeutic approaches.

Equine Pastern Dermatitis (EPD) is a common but often debilitating skin condition found on a horse’s lower leg area. This review provides an overview of the known clinical presentation, risk factors, prevention and treatment methods of EPD.

Clinical Presentation

• EPD is a cutaneous reaction that typically occurs in the palmar/plantar area of a horse’s pastern, essentially a skin disorder at the lower portion of a horse’s legs.
• This review examines the various forms of EPD and discusses clinical score evaluation methods and how to differentiate the disease from other similar conditions.

Risk Factors

• EPD’s occurrence is associated with several intrinsic and extrinsic risk factors with the majority of studies focused on these aspects.
• Data suggests that age, breed, and breed-related characteristics such as having feathers and a large cannon circumference (the cylindrical part of the lower leg) can impact both the prevalence and the severity of EPD.
• Limbs that are unpigmented or are hind limbs are known to be affected more often.
• While genetic effects are notable in draft breeds, their complexity is yet to be understood. Commercial genetic tests for these do not yet exist.
• The relationship between EPD and rainfall or humidity is inconclusive.
• Studies consistently report associations of EPD with Chorioptes infestation and bacterial microbiome imbalances, but not fungal infections. However, it is yet to be confirmed if specific infectious agents are the direct cause.

Therapeutic Approaches and Prevention

• Regarding treatment, the research examined the effects of antibacterial agents (Kunzea oil, phytosphingosines, triclosan), fatty acids, aromatic oils and humectants, and specific approaches to treat Chorioptes infestation in EPD-affected horses.
• Current treatment methods, however, remain largely empirical due to the complexity of this multifactorial syndrome. That being said, understanding the investigated risk factors can aid in the development of better diagnostics and treatments.
• According to the study, improving horse owner awareness of EPD may be a crucial step in safeguarding the welfare of affected horses.