Phycomycosis is an uncommon disease of the
gastrointestinal tract most commonly found in
dogs. The
disease is caused by a variety of
molds and
fungi.
Pythiosis is the most common type and is caused by
Pythium,
a type of
water mould. Phycomycosis can also be caused by two types of
zygomycetes,
Entomophthorales (such as
Basidiobolus and
Conidiobolus) and
Mucorales (such as
Mucor,
Mortierella,
Absidia,
Rhizopus, and
Rhizomucor).
Pythiosis occurs most commonly in dogs and
horses, but is
also found in cats,
cattle, and humans.
In the United States it is most commonly found in the Gulf states, especially
Louisiana.
Pythium occupies swamps in late summer and infects dogs who drink water
containing it. The disease is typically found in young, large breed dogs. Other
causes of phycomycosis are found throughout the U.S. and Europe.
The disease grows slowly in the
stomach and
small intestine, eventually forming large lumps of
granulation tissue. It can also invade surrounding
lymph nodes.
Symptoms include vomiting, diarrhea, depression, weight loss, and a mass in the
abdomen. Phycomycosis of the skin is very rare, and appears as
ulcerated lumps.
Diagnosis is through
biopsy.
Treatment is very difficult and includes
surgery when
possible.
Antifungal drugs show only limited effect on the disease. The
prognosis
is poor.
References
Ettinger, Stephen J.;Feldman, Edward C.(1995).Textbook of Veterinary
Internal Medicine(4th ed.). W.B. Saunders Company.
ISBN 0-7216-6795-3