Issue Description Dog Aspergillosis is a fungal infection that
invades the respiratory system, ears, throat and mouth. Dogs can
inhale fungi spores or �€œconidia�€� naturally present in the
environment, such as in straw, grass or grain. Common species are
Aspergillus fumigatus and Aspergillus tereus. The Aspergillus fungi
develop in tissue and lead to cell death and formation of abscesses.
Younger dogs under 7 years may suffer from two types of Aspergillus
infection: Aspergillosis or Disseminated Aspergillosis. Breeds
with medium and long noses, including German Shepherd Dogs, Labrador
Retrievers and Rottweilers, seem more prone to this infection that
affects dogs with poor or deficient immune systems. Dogs that sniff in
areas with fungal contamination may also be affected. Other Names Nasal Aspergillosis, Disseminated Aspergillosis
Symptoms Symptoms of Aspergillosis include nasal
discharge, often odorous, and nose bleeds. Ulcerations may appear on
the external part of the nose, at the edges of the nostrils. Dogs may
experience pain or discomfort in the nose or facial region. This
invasive infection destroys the bones of the sinuses. Symptoms of
Disseminated Aspergillosis include bone infection. Which part of the
body the fungus infects can determine the symptoms. The fungus invades
the respiratory tracts or other organs through the bloodstream. The
fungi may also attack the intervertebral discs of the spine. Common
signs include weakness, uveitis (deep inflammation of the eye), fever,
lameness, draining tracts, appetite loss and other symptoms that often
show too late in a systemic disease. German Shepherd Dogs may be more
prone to Disseminated Aspergillosis.
Diagnosis Diagnosis may be from two of the following
criteria: radio graphs, fungal plaques, tissue biopsy or nasal
discharge, or a blood test that is positive for antibodies. X-rays may
reveal bone destruction patterns. Problems with antibody tests include
knowing what species of Aspergillus to test.
Treatment Treatment of Dog Aspergillosis may be topical
or systemic. Topical treatment requires infusion into the sinus
cavities. Under general anaesthesia, the dog's throat is closed at the
back with gauze and foley catheters. The topical antifungal agent of
60 ml of 1% clotrimazole solution infuses the nose and frontal sinuses
under pressure. After the incubation period, the clotrimazole is
drained and suctioned.
Some patients require long periods
of treatment sessions. More promising is the combination of
clotrimazole irrigation and depot therapy that allows a shorter
treatment and lower patient morbidity. This process includes a
five-minute flushing of 1% topical clotrimazole solution, then an
application of 1% clotrimazole cream as a deposit agent into the
frontal sinuses. After removal of the catheters, the skin incisions
are closed. After the excess fluid drains, then the gauze is removed.
This treatment has a success rate of 86%.
Systemic treatment includes oral antifungal drugs such as itraconazole
or fluconazole. Surgical treatment is an extreme resort.
Treating Disseminated Aspergillosis may include the older antifungal
drug Amphotericin B that carries the risk of causing kidney damage.
Newer drugs may not cause as much damage, yet may not be as an
effective treatment. Several years of itraconazole may be of benefit.