Severe inflammation of feet and legs from generalized
demodex. In generalized demodecosis there is a genetic defect that leads to an inability on the part of the dog’s immune system to fight off this mite in most cases. Most dogs with immune system disorders that allow demodecosis to occur develop it at a younger age, usually less than one year of age. In dogs in which demodecosis occurs later, there is often something causing significant compromise of the immune system. Cushing’s disease, liver disease, diabetes, high doses of prednisone or other cortisones, cancer and other strong suppressors of immune function can lead to adult onset demodecosis.

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