Broad categories of diseases affecting the skin include allergy (environmental, food), infection (bacteria, yeast), parasites (sarcoptic mange
, demodectic mange
, ticks, fleas, others), immune-mediated disease (several) and others.
A veterinarian's basic approach to skin disease is: a detailed history, a detailed physical examination, skin scrape, fungal culture, basic laboratory tests. Other tests or evaluations may be ordered based on those results.