Canine nasal disease Flashcards
What are the main ddx for nasal disease?
Neoplasia Lymphocytic plasmacytic rhinitis Tooth disease FB Parasites Aspergillus Bacterial Rhinitis Cleft palate Oro-nasal fistula Coagulopathy
What are the differentials when there is loss of bone on imaging?
Loss of turbinate detail - Aspergillosis
Loss of turbinate detail with soft tissue opacity -Neoplasia
Bone lysis - Neoplasia, aspergillosis
Is culture of nasal biopsies a good idea?
Often not, not even clear if bacterial rhinitis is a thing, and will just get a mix of commensals
What causes sinonasal aspergillosis?
most often caused by Aspergillus fumigatus, a filamentous saprophyte and ubiquitous fungus, although infections with other Aspergillus species, Penicillium species and Cryptococcus neoformans have been reported.
What are the clinical signs of nasal aspergillosis?
The disease is typically unilateral on first presentation, but progresses to become bilateral. Typical clinical signs are profuse mucopurulent to purulent nasal discharge, nasal pain and ulceration/depigmentation of the nasal planum. Sneezing, reverse sneezing, epistaxis, depression and decreased appetite can also be seen. The presence of facial or nasal pain and ulceration/depigmentation of the nasal planum help to differentiate it clinically from some of the other causes of nasal discharge
How do you diagnose nasal aspergillosis?
Radiographic findings can include radiolucency in the rostral nasal cavity in conjunction with increased radiopacity in the caudal aspect
Increased radiopacity is also often found in the frontal sinus, due to fungal disease or fluid from reduced
drainage through the nasofrontal ostium.
‘gold standard’ for diagnosis of the disease remains
direct visualisation of fungal plaques during rhinoscopy or identification of fungal elements on cytology or histopathological examination.
Rhinoscopically, destruction of the turbinates is often
seen with aspergillosis, creating a ‘cavernous’ appearance
Fungal colonies will be recognised
as grey, white or yellow plaques if present
How do you treat aspergillosis?
Topical instillation of antifungal
drugs, especially clotrimazole or enilconazole, has
been associated with greater success than oral therapy.
There are a number of options for instillation of topical
therapy, including nasal cavity catheters, intrasinus
Jamshidi needles and indwelling frontal sinus tubes.
Oral therapy is reserved for refractory cases as it is associated with hepatotoxicity, and takes a very long time
Surgical extirpation of the frontal sinuses is performed in dogs with large fungal plaques, followed by
application of topical clotrimazole
Aspergillomas in the frontal sinus are debrided
surgically if identified on CT. Rhinotomy offers a last
resort for animals with refractory disease or where
the diagnosis has not been made, but surgery by no
means guarantees success.q
What is the prognosis for aspergillosis?
dogs may suffer from nasal discharge after recovery from sinonasal aspergillosis.
In most cases it is a secondary bacterial rhinitis that will respond to antibiotics, although sometimes it
may be the end result of severe turbinate destruction
What are the signs of cryptococcus? how do you diagnose it?
sneezing, nasal discharge, epistaxis and nasal deformity.
Rhinoscopy may reveal roughened, erythematous nasal turbinates, and fungal granuloma may be seen as a mass lesion. The latter may also be visible on diagnostic imaging. Diagnosis is by demonstration of the fungus on histopathology as well as by tissue culture and serum antigen titres.
What types of dogs are more at risk of nasal neoplasias?
older, medium to large breed dogs and it has been suggested that being dolichocephalic, living in an urban environment and being exposed to tobacco smoke all lead to increased risk.
What are the most common nasal neoplasias?
Carcinomas (adenocarcinoma, squamous cell
carcinoma and undifferentiated carcinoma) represent
approximately two thirds of tumours, with sarcomas
(fibrosarcoma, chondrosarcoma, osteosarcoma and
undifferentiated sarcoma) comprising the majority of
the rest. There are occasional reports of other tumours;
for example, melanoma.
How does nasal neoplasia start out?
Nasal neoplasia is typically a unilateral disease process, at least initially, and the average duration of clinical signs before diagnosis is three months.
What are typical clinical signs of nasal neoplasia?
nasal discharge, epistaxis, sneezing, stertor, stridor and epiphora. Air flow will typically be reduced on
the affected side.
Can progress to facial deformity and pain, exophthalmus, intractable epistaxis and seizures if there is invasion into the cranium, usually via the cribriform plate.
How do you diagnose nasal neoplasia?
A definitive diagnosis of nasal neoplasia can only
be made by histology. Supportive data can be obtained with imaging (radiography, CT or MRI) and rhinoscopy
A nasal flush should always be performed in cases
of suspected nasal neoplasia, as a piece of the tumour
is occasionally dislodged and later identified when the
pharyngeal packing is removed.
What is the MST for a dog with nasal carcinoma?
in untreated dogs with carcinoma was just 88 days for
dogs with epistaxis and 224 days for those without.
How do you treat nasal neoplasia?
aimed at slowing progression and reducing tumour mass; this is best achieved with fractionated radiation therapy, which is very well tolerated by most dogs, although loss of sight in at least one eye will be seen in almost half of dogs treated this way. Median survival and one- and two year survival times vary between reports
What is idiopathic lymphoplasmacytic rhinitis?
microscopically characterised by infiltration of the nasal mucosa with lymphocytes and plasma cells, although variable numbers of neutrophils and eosinophils may also be present.
The definitive cause of LPR is unknown, although some authors believe that the condition is a chronic inflammatory response to an inhaled irritant, pollutant or allergen. An immune-mediated pathogenesis has also been suggested, but poor glucocorticoid response in most dogs with LPR does not support this hypothesis
What does lymphoplasmacytic rhinitis present concurrently with?
nasal neoplasia, fungal rhinitis, dental disease, oronasal fistula or foreign body rhinitis; therefore it is imperative that these diseases be thoroughly excluded before a definitive diagnosis is made
How does lymphoplasmacytic rhinitis appear on imaging?
CT images may mimic fungal rhinitis as turbinate
destruction occurs in some cases, although typically
the changes are not as pronounced and destruction of the nasal septum, bones of the frontal sinuses and cribriform plate are not expected. Frontal sinus opacification on CT can occur due to fluid trapping. Changes on endoscopy are non-specific
How do you treat lymphoplasmacytic rhinitis?
extremely frustrating and a cure is rarely achieved.
Allergen avoidance is usually unhelpful and difficult to
accomplish.
While systemic corticosteroids are seldom
effective in controlling clinical signs, inhaled steroid
therapy (eg, fluticasone propionate or beclomethasone) does seem to lead to a partial improvement in some animals.
Antihistamine medications are rarely effective but can reduce severity
Long-term administration of antibiotics that have immunomodulatory effects, combined with nonsteroidal anti-inflammatory agents, can be helpful in some animals. Doxycycline is frequently trialled for a
period of four to six weeks; however, as recent studies
have failed to identify any infectious agent associated
with this disease, any beneficial effect may well be from immunomodulation.
What is Pneumonyssoides caninum?
canine nasal mite.
The life cycle and mode of transmission of the parasite
are not fully known. Cases typically present with nonspecific signs referable to the upper respiratory tract, including sneezing and reverse sneezing. P caninum has recently been identified in the UK. Treatment options include milbemycin oxime 1 mg/kg given orally three times at 10-day intervals. This dose regimen is more frequent than the monthly dose of 6 to 12 mg/kg recommended for flea infestations.
