Aetiology and diagnosis of persistent nasal disease in the dog: a retrospective study of 42 cases

Association of magnetic resonance imaging findings and histologic diagnosis in dogs with nasal disease: 78 cases (2001-2004)

OBJECTIVE-To determine whether magnetic resonance imaging (MRI) features correlated with histologic diagnosis in dogs with nasal disease. DESIGN-Retrospective case series. ANIMALS-78 Dogs undergoing MRI for evaluation of nasal disease. PROCEDURES-Medical records and MRI reports of dogs were reviewed to identify MRI features associated with histologic diagnosis. Features evaluated were presence of a mass effect, frontal sinus involvement, sphenoid sinus involvement, maxillary recess involvement, nasopharyngeal infiltration by soft tissue, nasal turbinate destruction, vomer bone lysis, paranasal bone destruction, cribriform plate erosion, and lesion extent (ie, unilateral vs bilateral). RESULTS-33 Dogs had neoplastic disease, 38 had inflammatory rhinitis, and 7 had fungal rhinitis. Lesion extent was not significantly associated with histologic diagnosis. Absence of a mass effect was significantly associated with inflammatory disease. However, presence of a mass was not specific for neoplasia. In dogs with evidence of a mass on magnetic resonance (MR) images, nasal turbinate destruction, frontal sinus invasion, and maxillary recess invasion were not useful in distinguishing neoplastic from nonneoplastic disease, but cribriform plate erosion, vomer bone lysis, paranasal bone destruction, sphenoid sinus invasion, and nasopharyngeal invasion were. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that in dogs with nasal disease, the lack of a mass effect on MR images was significantly associated with inflammatory disease. In dogs with a mass effect on MR images, vomer bone lysis, cribriform plate erosion, paranasal bone destruction, sphenoid sinus invasion by a mass, and nasopharyngeal invasion by a mass were significantly associated with a diagnosis of neoplasia.

Retrospective review of 50 canine nasal tumours evaluated by low-field magnetic resonance imaging

OBJECTIVES

Low-field magnetic resonance imaging machines are being used more often in veterinary practice for the investigation of sinonasal disease. The aim of this retrospective study was to describe and characterise the low-field magnetic resonance imaging features of nasal tumours in dogs.

METHODS

The Queen's Veterinary School Hospital magnetic resonance imaging database (2001-2005) was searched for dogs with a magnetic resonance imaging diagnosis of a nasal tumour. Fifty cases with histological diagnosis of nasal tumour were found. The appearance and extent of the nasal tumour as well as the involvement of adjacent anatomic structures were examined against a checklist.

RESULTS

The most common magnetic resonance imaging findings were as follows. (1) Soft tissue mass replacing the destroyed nasal conchae and/or ethmoturbinates (98 per cent of cases). (2) Nasal septum destruction (68 per cent of cases). (3) Retained secretions with or without mass caudally in frontal sinuses (62 per cent of cases). (4) Nasal/frontal bone destruction (52 per cent of cases). Low-field magnetic resonance imaging allowed differentiation of tumour tissue from retained secretions or necrotic tissue. Magnetic resonance imaging was invaluable in assessing the extension of the tumour into the maxillary recesses, caudal recesses, nasopharynx, adjacent bones and cranial cavity. The tumour often extended caudally into the frontal sinuses, nasopharynx and perhaps most importantly into the caudal recesses. Tumour extension into the cranial cavity was not common (16 per cent), and only three of these cases showed neurological signs. However, 54 per cent of cases showed focal meningeal (dural) hyperintensity, although the significance of this is unclear. A significant difference (P<0.05) in tumour signal intensity between the sarcomas and carcinomas was found.

CLINICAL SIGNIFICANCE

The use of a low-field magnetic resonance imaging technique is excellent for the diagnosis and determination of extent of sinonasal tumours.

Prevalence, clinical features, and causes of epistaxis in dogs: 176 cases (1996-2001)

OBJECTIVE

To determine prevalence, clinical features, and causes of epistaxis in dogs.

DESIGN

Retrospective case series.

ANIMALS

176 dogs with epistaxis.

PROCEDURES

Medical records were reviewed for information related to signalment, clinical features, diagnosis, and outcome.

RESULTS

132 (75%) dogs were initially examined by the hospital's emergency service; prevalence of epistaxis was 0.3%. Dogs with epistaxis were more likely to be old (> or = 6 years), male, and large (> or = 26 kg [58.5 lb]) than were dogs in a reference population. In 109 (62%) dogs with epistaxis, an underlying cause was identified; 115 underlying disorders were identified, with 90 classified as local and 25 classified as systemic. Local causes of epistaxis included nasal neoplasia (n = 35), trauma (33), idiopathic rhinitis (20), and periapical abscess (2). Systemic causes included thrombocytopenia (12), thrombocytopathia (7), coagulopathy (3), hypertension (2), and vasculitis (1). Dogs with local causes were more likely to have unilateral than bilateral epistaxis, but 11 of 21 (52%) dogs with systemic disorders also had unilateral epistaxis. Dogs with systemic disorders were more likely to have clinical signs of systemic disease. Duration of epistaxis (acute vs chronic), severity, and duration of hospitalization were similar for dogs with local versus systemic disorders.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that epistaxis was a common disorder in dogs and frequently regarded as an emergency. Local causes of epistaxis were predominant, but clinical features traditionally thought to be helpful in distinguishing local versus systemic causes could not be reliably used for this purpose.

A retrospective study of 61 cases of spontaneous canine epistaxis (1998 to 2001)

OBJECTIVES

To determine the prevalence and identify possible clinicopathologic indicators of the diseases associated with canine epistaxis.

METHODS

The medical records of 61 dogs with epistaxis were reviewed.

RESULTS

Systemic diseases, diagnosed in fifty-six dogs, included canine leishmaniasis in twenty-three dogs, canine monocytic ehrlichiosis in twenty-two, concurrent canine leishmaniasis and canine monocytic ehrlichiosis in six, rodenticide toxicity in two and primary immune-mediated thrombocytopenia, suspected oestrogen toxicity and systemic arterial hypertension in one dog each. Intranasal diseases were documented in the remaining five dogs, including transmissible venereal tumour in three dogs, and nasal adenocarcinoma and nasal aspergillosis in one dog each. Mucosal pallor and a generalised bleeding tendency were significantly more common among dogs with canine monocytic ehrlichiosis compared with those with canine leishmaniasis, whereas the opposite was true for peripheral lymphadenomegaly. Also, dogs with canine monocytic ehrlichiosis presented with pancytopenia more frequently compared with those with canine leishmaniasis; in the latter dogs, the median values of haematocrit, leucocyte and platelet counts and serum total protein concentrations were higher.

CLINICAL SIGNIFICANCE

Canine leishmaniasis and canine monocytic ehrlichiosis are the leading causes of canine epistaxis in Greece. Mucosal pallor, bleeding tendency and pancytopenia are more likely to be indicative of canine monocytic ehrlichiosis, as opposed to peripheral lymphadenomegaly and hyperproteinaemia in canine leishmaniasis.

Clinical features of epistaxis in dogs: a retrospective study of 35 cases (1999-2002)

Epistaxis was retrospectively evaluated in 35 dogs. Systemic disease was diagnosed in seven dogs and intranasal disease in 29. Nineteen dogs with intranasal disease had neoplasia. Dogs with neoplasia were older (mean 10.0 years) than dogs with nonneoplastic intranasal disease (mean 5.6 years). Signs persisting for >1 month occurred more often in dogs with intranasal than systemic disease. Unilateral epistaxis did not distinguish intranasal from systemic disease. Only dogs with intranasal disease had facial deformity, decreased airflow, or regional sub-mandibular lymphadenopathy. Dogs with systemic disease had a lower packed cell volume (mean 31.8%) than dogs with intranasal disease (mean 42.7%).

Nasal computed tomography

Chronic nasal disease is often a challenge to diagnose. Computed tomography greatly enhances the ability to diagnose chronic nasal disease in dogs and cats. Nasal computed tomography provides detailed information regarding the extent of disease, accurate discrimination of neoplastic versus nonneoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.

Canine nasal aspergillosis

Chronic nasal discharge is a common clinical sign of disease in dogs. Canine sinonasal aspergillosis is a relatively common disease in dogs. The three hallmarks of canine nasal aspergillosis are a profuse mucoid to hemorrhagic chronic nasal discharge that may alternate with periods of epistaxis, ulceration of the external nares with crusting, and pain or discomfort in the facial region. Diagnostic imaging (preferably computed tomography, CT) of the nasal cavity and paranasal sinuses is an important component of the evaluation of dogs with signs of nasal disease. Rhinoscopy is an important part of both the diagnosis and the therapy for nasal aspergillosis. Therapeutic recommendations for sinonasal aspergillosis have included surgery and the use of several systemic and topical antifungal drugs.

Radiographic techniques of the nasal cavity and sinuses

Diseases of the nasal cavity and sinuses can be frustrating problems for owners and veterinarians alike. Initial physical examination and routine blood work are often unrewarding in directing the clinician at a diagnosis. Diagnostic imaging can help characterize the disease process and direct treatment or further diagnostics. Radiographs of the skull are an excellent first-line diagnostic step in the analysis of nasal disease. The following article reviews basic techniques, positioning, and interpretation of radiographs of the nasal cavity and paranasal sinuses.

Computed tomography as an aid in the diagnosis of chronic nasal disease in dogs

OBJECTIVES

To assess the use of computed tomography (CT) in the diagnosis of chronic nasal disease in dogs.

METHODS

A retrospective study of 85 dogs with chronic nasal discharge due to primary nasal disease, which had undergone nasal CT and biopsy, was carried out. Medical records were reviewed for signalment, clinical signs, CT findings, endoscopic findings and histopathology. The results obtained via CT were correlated with nasal histopathology and gross anatomical observations were recorded at the time of rhinoscopy.

RESULTS

Neoplasia was diagnosed in 37 dogs for which CT typically revealed a soft tissue density associated with extensive turbinate destruction. Inflammatory rhinitis was diagnosed in 40 dogs. CT disclosed either normal turbinate structures or mild to moderate turbinate destruction, with or without the presence of soft tissue densities (mucopus) within the nasal passages. Fungal rhinitis was diagnosed in seven dogs for which CT disclosed extensive turbinate destruction with hyperlucency of the nasal passages. One dog had normal CT and histopathology findings.

CLINICAL SIGNIFICANCE

CT greatly enhanced the ability to diagnose chronic nasal disease in dogs, providing detailed Information regarding the extent of the disease, accurate discrimination of neoplastic versus non-neoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.

An immunohistochemical study of canine nasal aspergillosis

In this study, histochemistry and immunohistochemistry were used to characterize the phenotype and distribution of leucocytes in the distal nasal mucosa of 15 dogs with nasal aspergillosis. The most consistent histopathological finding was a severe, predominantly lymphoplasmacytic, inflammatory infiltration of the lamina propria. Fungal hyphae were not observed to invade the mucosa but were found at the mucosal surface and within material collected from the nasal cavity. The main immunohistochemical findings were (1) a predominance of IgG(+) plasma cells over IgA(+) and IgM(+) plasma cells, (2) significant numbers of macrophages and dendritic cells expressing MHC class II molecules, (3) macrophages and neutrophils expressing L1 antigen and (4) a mixture of CD4(+) and CD8(+) T cells. These findings are consistent with a dominant Th1-regulated cell-mediated immune response. The nature of the inflammatory infiltrate and the lack of invasiveness of the mucosa by the fungus, together with the clinical course of the disease and the apparent immunocompetence of the affected dogs, suggest that canine nasal aspergillosis resembles the chronic erosive non-invasive fungal sinusitis described in human patients.

Idiopathic lymphoplasmacytic rhinitis in dogs: 37 cases (1997-2002)

OBJECTIVE

To determine clinical signs and rhinoscopic, computed tomographic, and histologic abnormalities in dogs with idiopathic lymphoplasmacytic rhinitis.

DESIGN

Retrospective case series.

ANIMALS

37 dogs.

PROCEDURE

Clinical information was obtained from medical records. Nasal computed tomographic images and histologic slides of biopsy specimens were reviewed.

RESULTS

Dogs ranged from 1.5 to 14 years old (mean, 8 years); most (28) were large-breed dogs. Nasal discharge was unilateral in 11 of 26 (42%) dogs and bilateral in 15 of 26 (58%) dogs. In dogs with unilateral disease, duration of clinical signs ranged from 1.5 to 36 months (mean, 8.25 months; median, 2 months), and in dogs with bilateral disease, duration of signs ranged from 1.25 to 30 months (mean, 6.5 months; median, 4 months). Computed tomography (n = 33) most often revealed fluid accumulation (27/33 [82%]), turbinate destruction (23/33 [70%]), and frontal sinus opacification (14/33 [42%]). Rhinoscopy (n = 37) commonly demonstrated increased mucus and epithelial inflammation; turbinate destruction was detected in 8 of 37 (22%) dogs. Bilateral biopsy specimens from all 37 dogs were examined. Four dogs had only unilateral inflammatory changes. The remaining 33 dogs had bilateral lesions; in 20, lesions were more severe on 1 side than the other.

CONCLUSIONS AND CLINICAL RELEVANCE

Findings suggest that idiopathic lymphoplasmacytic rhinitis is a key contributor to chronic nasal disease in dogs and may be more common than previously believed. In addition, findings suggest that idiopathic lymphoplasmacytic rhinitis is most often a bilateral disease, even among dogs with unilateral nasal discharge.

Investigation of nasal disease in the cat--a retrospective study of 77 cases

A retrospective study was undertaken to determine the prevalence of different diseases in cats referred for investigation of chronic nasal disease, to identify historical, clinical and diagnostic features which may assist in making a diagnosis, and to provide information pertaining to outcome in these cats. Diagnoses included neoplasia (30 cases), chronic rhinitis (27), foreign body (8), nasopharyngeal stenosis (5), Actinomyces infection (2), nasal polyps (2), stenotic nares (2), and rhinitis subsequent to trauma (1). The most common neoplasia was lymphosarcoma (21 cases), with a median survival of 98 days for cats treated with multiagent chemotherapy. Cats with neoplasia were older on average than the other cats, and were more likely to be dyspnoeic and have a haemorrhagic and/or unilateral nasal discharge than cats with chronic rhinitis. Cats with neoplasia were more likely to have radiographic evidence of nasal turbinate destruction, septal changes, or severe increases in soft tissue density than cats with chronic rhinitis. It was unusual for cats with diseases other than neoplasia to be euthanased as a result of their nasal disease.

Use of topical povidone-iodine dressings in the management of mycotic rhinitis in three dogs

Three dogs with mycotic rhinitis were treated with a proprietary wound dressing product intended to produce a sustained release of povidone-iodine. All of the dogs had been refractory to other treatments. One dog had extensive soft tissue involvement, including extension into the orbital tissues, and another had evidence of involvement of the supporting bones of the nose. In all cases, the affected nasal cavity and/or frontal sinus was exposed via a dorsal approach and partial turbinectomy was performed. The wound dressing was applied and retained with a 'tie-over' dressing. The dressing was replaced every 48 to 72 hours until all exposed tissue was covered by healthy granulation tissue, at which time the rhinotomy was closed by soft tissue reconstruction. There was no evidence of recurrence of the fungal infection at follow-up times of up to 20 months postsurgery.

Long-term outcome of 56 dogs with nasal tumours treated with four doses of radiation at intervals of seven days

A retrospective study was undertaken on 56 dogs treated for nasal tumours by megavoltage radiotherapy with a hypofractionated schedule consisting of four doses of 9 Gy given at intervals of seven days. The dogs were followed until they died or were euthanased. The clinical signs had improved in 53 of the 56 dogs by the end of the treatment schedule. Mild acute radiation side effects were observed in the majority of the dogs but late radiation side effects were rare. Kaplan-Meier survival analysis revealed a median survival time after the final dose of radiation of 212 days. The one- and two-year survival rates were 45 per cent and 15 per cent. Fifty of the dogs were euthanased because the initial clinical signs recurred.

Computed tomographic findings in 35 dogs with nasal aspergillosis

The purpose of this study was to describe the computed tomographic (CT) features of nasal aspergillosis in dogs. Initial (n = 35) and follow-up (n = 12) CT images were available from 35 dogs. The most commonly encountered CT findings were (1) moderate to severe cavitary destruction of the turbinates with presence of a variable amount of abnormal soft tissue in the nasal passages, (2) non-specific thickening of the mucosa adjacent to the inner surface of bones of the frontal sinus, maxillary recess and nasal cavity and, (3) thickened reactive bone. The findings were consistent with a disease initially affecting one nasal cavity then progressing into the ipsilateral frontal sinus, the contralateral nasal cavity and the contralateral frontal sinus. Two dogs with associated nasal foreign body had a more localized invasion of the nasal cavity. Attenuation values and contrast enhancement were not specific. With follow-up examinations, a reduction in the amount of abnormal soft tissue was observed in all dogs except one, but this reduction could not be quantified.