One study found that, while female dogs may have better survival rates with therapy, they are more likely to suffer relapses than males. The disease process Dogs usually acquire blastomycosis by inhaling the spores from the soil into the lungs, where it induces a self-limiting pulmonary infection. Direct inoculation of the spores into the skin through puncture wounds may cause local cutaneous infection. By far, the most common form of blastomycosis seen by veterinarians is the generalized or disseminated form, which spreads via the bloodstream or lymphatic system from the lungs to involve the eyes, brain, bone, lymph nodes, urogenital system, skin, and subcutaneous tissues. Diagnosis Diagnosis of blastomycosis involves finding the yeast organism in samples from draining skin lesions or a lymph node.
Serum chemistries are usually within normal limits.
Fungal titers confirm the diagnosis and help differentiate blastomycosis from histoplasmosis, a related fungal condition with similar signs and geographic distribution. About 65 percent of dogs diagnosed with blastomycosis do survive. Because the treatment is long, complicated, and expensive with the potential for serious side effects, some owners elect to euthanize affected pets. In treated dogs, survival rates are approximately 85 percent, with up to 25 percent suffering relapses. Dogs with brain or eye involvement have a worse prognosis, and dogs with poor liver or kidney function may not be able to tolerate the necessary medications that must be metabolized by these organs.