What is aspergillosis?
Aspergillus is a species of fungus, and aspergillosis refers to when it infects your pet. It rarely causes disease in healthy dogs, however, if the opportunity arises to infect a sick and/or immune-compromised dog, they will seize it – hence why it is referred to as an “opportunistic infection”. Aspergillus is very common in the environment; it lives in dust, hay, and straw, for example. Despite this, it is only, generally, sick pooches who become victims to fungal infection. Now we must ask, what does it mean to contract this fungal infection?
There are two forms of disease –nasal and disseminated.
Nasal – as you would expect, this is a localised Aspergillus infection of the nose. Our long-nosed friends are particularly susceptible; “doliocephalic breeds”, a.k.a super-sized-snouters such as the Afghan or greyhound, for example. Doliocephalic breeds have “more nose” to be potential Aspergillus real-estate; the fungus enters through the nostrils, and can colonise these abundant nasal passages, and even the frontal sinuses inside the skull.
Disseminated – disseminated means widely spread, hence this type of aspergillosis affects the whole body. German Shepherds are thought to be particularly susceptible. After breathing in the spores, the fungus spreads beyond the respiratory tract into the other organs of the body; unlike with the nasal form. But why the fungus takes hold of our four-legged friends in this way is less clear.
So, what do we know so far? We know that…
- Aspergillosis is an opportunistic infection by a species of fungus called Aspergillus.
- If Aspergillus affects just the nasal passages, it is known as nasal aspergillosis, whereas if it affects the entire body, it is known as disseminated aspergillosis.
- Aspergillus is ubiquitous in the environment, but thankfully rarely causes a problem in healthy dogs; unfortunately, however, immunocompromised pooches are particularly at risk.
We now need to know why is aspergillosis an issue, and how can we tackle it?
How does aspergillosis affect your dog?
Aspergillosis is bad news because it causes discomfort for poor Lassie; generally, it will cause nasal pain and discomfort in the nasal form, or general sickness in the disseminated form.
Symptoms of nasal aspergillosis:
- Bleeding from the nose (“epistaxis”)
- Sneezing and pawing at the nose, indicative of nasal pain and discomfort
- Nasal discharge; it may be clear (serous) or discoloured and thick (mucoid), or look like pus (purulent)
- Sometimes, there may be some swelling of the face (“facial deformity”) as the mass of fungus pushes the nasal bones outwards
Symptoms of disseminated aspergillosis:
- Systemic “unwellness”, including tiredness and lethargy
- Gastrointestinal signs – a reduced appetite, vomiting, diarrhoea and weight loss
- Lameness; pain in the joint and bones may be a result of infection setting hold in the skeletal system
- Eye damage and blindness quite commonly occurs
- Sometimes, there may be open wounds, with pus discharging from them, as the dog’s body tries to get rid of the fungi.
Aspergillosis is not pleasant for our beloved dogs – so what can we do about it?!
Diagnosis and Treatment of aspergillosis
- Diagnosis
This will depend on what type it is, but if you notice lethargy/dullness in your dog, gastrointestinal upsets or specific nasal discomfort, this may indicate that your dog has an Aspergillus infection; please come in and discuss this with us if you notice any possible signs!
For the nasal form, a procedure known as rhinoscopy can give a diagnosis; this involves having a look inside the nasal cavity at the mucus membranes which line the nasal cavity. Swabs can be taken, and we can see what we can grow!
The disseminated version is harder to diagnose; blood tests (biochemistry analyses) will be performed, alongside, usually, urine tests and sometimes scans or X-rays, then our vets will put all the information together to build up a picture of what’s going on.
- Treatment
Nasal aspergillosis is much easier to treat; generally, the nose will be flushed and anti-fungal medications inserted directed into the nose. This is typically done under a general anaesthetic.
Disseminated aspergillosis, unfortunately, is much harder to diagnose and treat. Anti-fungals are used systemically, and can be curative – although many cases, sadly, are too advanced to treat by the time they are diagnosed.
If you have any concerns about nasal discomfort or your dog seeming flatter than his usual charming self, do not hesitate to contact us!
“A dog can snap you out of any kind of bad mood that you’re in faster than you can think of” – Jill Abramson