Fungal Infections in Dogs: Pythiosis

Pythiosis in dogs is an infectious disease caused by a fungus-like organism, Pythiuminsidiosum, that naturally inhabits wetlands, ponds, and swamps.  In dogs, the disease usually is manifested by gastroenteritis or dermatitis.  Presumably dogs become infected by ingesting, or swimming in contaminated water.  ogs with gastrointestinal pythiosis often have a history of retrieving objects, such as sticks, from water and then chewing on them; young male retriever-type dogs are particularly at risk.  Dogs with open skin wounds are probably predisposed to acquiring cutaneouspythiosis.

Pythium insidiosum mold is found in North America, South America, South-East Asia, Eastern Australia, and New Zeeland. It lives in parts of the world where the winters are mild, since it needs standing water that does not freeze to survive. In the United States, Pythium insidiosum is most commonly found in the warm Gulf States (particularly Louisiana), but have also been detected in Eastern and Midwest states.

Symptoms of Pythiosis in Dogs

Weight loss, diarrhea and vomiting are symptoms in the most common gastrointestinal form of the infection. There may be and abdominal mass. The skin or subcutaneous variety of the infection is more uncommon and is more frequently found in the SE US.. Pythium enters the dog’s tissues via open sores and form swollen nodules. The infections will often open and drain.

 Diagnosis of Pythiosis

Pythium fungus infections may not be easily diagnosed. By taking biopsies and/or swabs they can be identified under microscopic study. These sample may also be cultured in the lab. In many cases though, pythiosis will be diagnosed once other illnesses have been ruled out.

Treatment of Pythiosis

Unless Pythium fungus infections are diagnoses early, they are usually fatal. Treatments with antifungals have been generally unsuccessful. Canine Pythiosis treatment usually involves lengthy and complicated surgery to remove the nodules. Unless all trace of nodules are successfully excised, the prognosis is quite poor.

After surgery anti-fungal medication are taken for three months or more. Itraconazole and Terbinafine hydrochloride may be prescribed. Anti-fungals have a limited effect and recurrence is common.

When humans are infected with Pythium insidiosum more alternatives are available, and veterinarian experts and researchers might be able to benefit from the comparative success reached on the human side of the medical field in their search for more efficient Pythiosis treatments for dogs. Humans have for instance been successfully treated with Caspofungin. The problem with Caspofungin is that it is very expensive, thereby out of reach for many dog owners. In both humans and horses with Pythiosis, immunotherapy have proven successful in the past and this might be a possible Pythiosis treatment for dogs as well.
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Fungal Infections in Dogs: Ringworm

Fungal Infections in Dogs: Aspergillosis

Fungal Infections in Dogs: Blastomycosis

Fungal Infections in Dogs: Histoplasmosis

Fungal Infections in Dogs: Cryptococcosis

Fungal Infections in Dogs: Coccidioides immitis/Valley Fever

Fungal Infections in Dogs: Sporotrichosis

Fungal Infections in Dogs: Zygomycosis

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