Atypical histopathological findings in a 15-year-old Warmblood gelding diagnosed with anhidrosis in a temperate climate

Summary This case report describes the atypical histopathological findings in a horse with anhidrosis that presented for evaluation of suspected respiratory disease during autumn/winter in a temperate climate. Anhidrosis in this horse was associated with mononuclear infiltration of T lymphocytes around sweat glands, a finding not previously reported in cases of equine anhidrosis. This report highlights the importance of considering anhidrosis as a differential diagnosis in the investigation of respiratory disease and illustrates that the condition can occur in horses residing in temperate climates.