Canine nasal disease

[Nasal obstruction: Odontogenic cysts in 4 brachycephalic dogs]

OBJECTIVE

Odontogenic cysts may be of developmental or inflammatory origin. They are frequently observed in brachycephalic dogs. Due to their expansive growth, cysts in the maxilla may extend into the nasal cavity, obstruct the nasal airway and cause nasal discharge. Epithelial cysts may lead to a comparable clinical picture. A new endonasal endoscopic intervention for the removal of these cysts is described.

MATERIAL AND METHODS

Four brachycephalic dogs (Boxer, Chihuahua, French bulldog, Pug) with unilateral cysts obstructing the nasal cavity were included in the study. The animals underwent clinical examination, computed tomography (CT) imaging and rhinoscopy examination. Histopathologic evaluation of the cyst wall was performed. In addition to dental surgery and conventional extraction of the involved tooth, the cyst wall was removed by endoscopic intervention via the physiologic nasal opening. Clinical course following treatment was assessed by rhinoscopy and CT.

RESULTS

The main clinical signs were unilateral or bilateral serous to hemorrhagic nasal discharge. Nasal airflow was restricted in all patients. Removal of the cysts and involved teeth did not lead to any intra- and postoperative complications. No recurrence of the cysts was observed. Histologic diagnosis consisted of an epidermoid cyst, a follicular cyst, a radicular cyst, and a canine odontogenic parakeratinized cyst (COPC). Neoplastic transformation was excluded in all cases.

CONCLUSIONS

Removal of the cyst wall may be performed by means of minimally invasive endoscopic intervention via the physiologic nasal entrance. The procedure is curative and carries the risk of only few complications. In cases in which treatment is restricted to extraction of the affected tooth, the nasal airway may remain obstructed due to a calcified cyst wall.

CLINICAL RELEVANCE

In brachycephalic dogs, oronasal defects due to dental pathology are the most common reason for chronic nasal discharge, whereas in normocephalic dogs nasal neoplasia are. Odontogenic cysts carry importance as differential diagnosis of nasal discharge.

Rhinoscopic Appearance and Clinical Features of a Nasal Transmissible Venereal Tumor in a Dog

A 2-year-old male neutered mixed breed dog was referred for evaluation of left-sided unilateral epistaxis and mucoid discharge following adoption from Mexico 2 months prior to presentation. Computed tomography (CT) showed soft tissue that filled the entirety of the left nasal passage with mild turbinate loss. Subsequent rhinoscopy revealed multifocal patches of discrete, white, wispy, vascularized abnormal tissue in the left nasal cavity. Cytology and histopathology procured with rhinoscopic-guidance were suspicious for transmissible venereal tumor (TVT). Confirmation of a TVT diagnosis was made with polymerase chain reaction for the long interspersed element inserted upstream of the c-myc gene. The dog was treated with 4 cycles of vincristine (0.5 mg/m², IV, once every 7 days) with complete and sustained resolution of clinical signs shortly after the third cycle. Nasal TVT in dogs is an uncommon presentation of a neoplasm that primarily results in genital or oral lesions. There is a void in the veterinary literature regarding the rhinoscopic appearance, as well as limited clinical descriptions of nasal TVT. Therefore, the objectives of this report were to provide a detailed description of the rhinoscopic appearance of a canine nasal TVT, in addition to clinical features, diagnostic findings, CT imaging, and successful therapeutic management.

Treatment of nasal tumours in dogs: a review

Nasal tumours are common neoplasms in dogs and often represent a diagnostic and therapeutic challenge due to their confined location within the nasal cavities. The main goal of this review is to extract the most relevant information from a wide and often confusing evidence-based medicine on the treatment of canine nasal tumours and conclude with current recommendations. This report highlights the different therapeutic modalities available and describes their technical aspects, interests and limitations. Megavoltage radiotherapy, as the most recent treatment and standard of care, is particularly examined, especially the different types of radiotherapy units, the main protocols used and their advantages and limits. Newer and non-conventional treatments are also discussed.

Upper digestive tract abnormalities in dogs with chronic idiopathic lymphoplasmacytic rhinitis

BACKGROUND

Chronic idiopathic lymphoplasmacytic rhinitis (CILPR) is a common inflammatory disorder of unknown etiology affecting the nasal cavity of dogs. The diagnosis is made by exclusion of other causes of nasal disease and specific therapeutic protocols are lacking. In human medicine, a relationship between CILPR and gastrointestinal clinical signs has been postulated, and remission of respiratory signs after clinical trials with medications for gastrointestinal disorders has been observed.

OBJECTIVES

To describe history, clinical presentation, endoscopic and histopathologic concurrent respiratory and digestive tract abnormalities, and to evaluate improvement of respiratory signs after treatment for gastrointestinal signs.

ANIMALS

Twenty-five dogs with CILPR.

METHODS

Prospective study. For inclusion, following information had to be available: respiratory and digestive clinical signs, airway and digestive tract endoscopic abnormalities, histologic evaluation of respiratory and gastrointestinal tract biopsy specimens, and clinical response to different treatment strategies.

RESULTS

Twenty-two dogs had endoscopic gastrointestinal lesions, whereas 13 dogs had concurrent gastrointestinal signs. Most esophageal and duodenal endoscopic abnormalities were classified as moderate or severe. Respiratory and gastrointestinal tract histologic evaluation identified mostly chronic inflammation. Remission or marked improvement of respiratory signs was observed in the majority of dogs treated only for gastrointestinal signs up to 12 months after endoscopy. No significant associations between treatments and follow-up information were found.

CONCLUSION AND CLINICAL IMPORTANCE

Nasal and upper digestive tract abnormalities coexist in some dogs with CILPR. Lack of standardized therapeutic protocols suggests caution when interpreting improvement in nasal clinical signs. Additional studies are needed to explore the possibility of a cause-effect relationship between the 2 processes.

Diagnostic Aspects of Veterinary and Human Aspergillosis

The genus Aspergillus is composed of more than 300 species, a fraction of which are involved in animal or human infections mostly following environmental exposure. Various risk factors (i.e., immunosuppression, tuberculosis) have been recognized for human whereas for veterinary infections, unhygienic management, trauma, anatomical conformation of the skull, or suspected immunological deficiencies have been suggested. In animals, aspergillosis is mostly sporadic but in some circumstance such as infections on poultry farms may involve the whole flock. Since the high prevalence of immunosuppression in human patients has not been mirrored in veterinary medicine, and although to the best of our knowledge, no comprehensive data on the prevalence of aspergillosis in animals has been published, their epidemiology has not changed during the last decades. The impact of these infections may be economic or if they are incurable, sentimental. The objective of the first part is to describe the diagnosis of the main clinical entities caused by Aspergillus spp. in animals. It includes disseminated canine aspergillosis, canine and feline sino-nasal and sino-orbital aspergillosis, guttural pouch mycosis in horses, mycotic abortion in cattle, mycotic keratitis in horses, and avian aspergillosis. When pathogenesis and clinical aspects are relevant for diagnosis—they will be addressed as well. The second part deals with human aspergillosis, which is a multifaceted disease, manifested in a spectrum of clinical entities affecting one or more organs. Diagnosis is based on the clinical manifestation, supported and confirmed by laboratory means, involving the classical approach of demonstrating the etiological agent in the clinical specimens and in culture. Noncultural methods, such as antigen detection and/or molecular assays to detect fungal nucleic acids or protein profiles, are used as well. The isolation and identification of the fungus allows the determination of its susceptibility to antifungal drugs. Thus, antifungal susceptibility testing maybe considered as part of the diagnostic process, which is of relevance for management of the infection. In this review article, the part dealing with diagnostic aspects of aspergillosis in humans concentrates on susceptibility testing of Aspergillus spp. to antifungal drugs and drug combinations. The technologies and methods of susceptibility testing are described and evaluated.

Emergence of nasal chondrosarcoma in a dog with nasal polyposis

Whilst the malignant transformation of nasal polyps or secondary development of nasal neoplasia after chronic inflammation is likely to be relatively rare, this potential complication should be considered, and the clinician should be vigilant for evidence of malignant transformation.

Use of a frameless computed tomography-guided stereotactic biopsy system for nasal biopsy in five dogs

CASE DESCRIPTION

5 dogs (median age, 9 years; median body weight, 31 kg [68.2 lb]) with undefined nasal masses were examined after undergoing CT of the head and nasal biopsy via a rostral rhinoscopic or unaided (blind) approach because histologic results for collected biopsy specimens (inflammatory, necrotic, or hemorrhagic disease) suggested the specimens were nonrepresentative of the underlying disease process identified via CT (aggressive or malignant disease).

CLINICAL FINDINGS

Clinical signs at the time dogs were evaluated included open-mouth breathing, sneezing, or unilateral epistaxis. Histologic findings pertaining to the original biopsy specimens were suggestive of benign processes such as inflammation. In an attempt to obtain better representative specimens, a frameless CT-guided stereotactic biopsy system (CTSBS) was used to collect additional biopsy specimens from masses within the nasal and sinus passages of the dogs. The second set of biopsy specimens was histologically evaluated.

TREATMENT AND OUTCOME

Histologic evaluation of biopsy specimens collected via the CTSBS revealed results suggestive of malignant neoplasia (specifically, chondrosarcoma, hemangiopericytoma, or undifferentiated sarcoma) for 3 dogs, mild mixed-cell inflammation for 1 dog, and hamartoma for 1 dog. No complications were reported. These findings resulted in a change in treatment recommendations for 3 dogs and confirmed that no additional treatment was required for 1 dog (with hamartoma). For the remaining dog, in which CT findings and clinical history were strongly suggestive of neoplasia, the final diagnosis was rhinitis.

CLINICAL RELEVANCE

Biopsy specimens were safely collected from masses within the nasal and sinus passages of dogs by use of a frameless CTSBS, allowing a definitive diagnosis that was unachievable with other biopsy approaches.