Aspergillus fumigatus

What is Aspergillus fumigatus?

Aspergillus fumigatus is a type of mold that belongs to the genus Aspergillus. These fungi are ubiquitous, i.e. they are found everywhere in the environment. They can colonize and multiply on various substrates such as plants, wood, soil or food. They form spores that spread through the air and can be inhaled.

Aspergillus fumigatus is usually harmless to humans and animals, unless they have a weakened immune system or previous damage to the respiratory tract. Then the fungus can cause an infectious disease called aspergillosis.

How can Aspergillus fumigatus infect dogs?

Dogs can ingest Aspergillus fumigatus by inhaling the fungal spores or coming into contact with the fungus through wounds. The most common form of infection is nasal aspergillosis, which affects the nasal cavity and paranasal sinuses. This mainly occurs in dogs that like to dig around in mulch made of leaves or damp earth or live in dusty environments.

Nasal aspergillosis can be chronic or acute. The chronic form is usually limited to one or both nasal cavities and causes inflammation of the nasal mucosa and bone. The acute form is rarer and more aggressive and can spread to the brain or other organs.

Another form of infection is disseminated aspergillosis, which is not limited to the nasal area. This occurs more frequently in German Shepherds and can affect various organs such as the lungs, bones, kidneys or CNS. Disseminated aspergillosis is difficult to diagnose and treat and has a poor prognosis.

What are the symptoms of a dog with Aspergillus fumigatus?

The symptoms of aspergillosis depend on the form and extent of the infection. Nasal aspergillosis usually presents with the following signs:

• Chronic mucopurulent nasal discharge (yellow-greenish or bloody)
• sneezing
• Nasal pain
• Sensitivity to touch on the face or nose
• Depigmentation or ulceration of the nasal passages
• Loss of appetite
• weight loss

Disseminated aspergillosis manifests itself with non-specific symptoms such as

• Fever
• vomiting
• pain
• lameness
• Swelling of the lymph nodes
• Neural deficits

How is Aspergillus fumigatus treated in dogs?

The treatment of aspergillosis requires professional care from a veterinarian. There are various treatment options, depending on the form and severity of the infection.

Oral administration of antifungal drugs such as itraconazole is a first line treatment for nasal or disseminated aspergillosis. These drugs inhibit the growth of the fungus in the body, but must be administered over several weeks to months.

Another option for nasal aspergillosis is the topical application of antimycotics such as clotrimazole or enilconazole. The medication is applied directly into the nasal cavities to kill the fungus. This can be done under anesthesia or with a catheter. Topical therapy has a higher success rate than oral therapy, but is also more invasive and more expensive.

Disseminated aspergillosis is difficult to treat and often has a poor prognosis. Oral administration of antimycotics can alleviate the symptoms, but does not always cure the infection. In some cases, surgical removal of the affected organs or amputation of the affected limbs may be necessary.