Nasopharyngeal disease in cats: 2. Specific conditions and their management

Feline Aural Inflammatory Polyps

Feline aural inflammatory polyps originate from the tympanic bulla and less frequently from the auditory tube, representing the most common benign tumor of the feline ear. Clinical signs may be compatible with otitis externa, media, and/or interna with rare occurrences involving meningoencephalitis or abscessation of periauricular tissue. Traction and avulsion is an effective treatment procedure with a relatively low recurrence rate, especially when systemic glucocorticoids are given after polyp removal. Secondary infections should be addressed with topical and systemic antimicrobials along with lavage of the ear. Bulla osteotomy may be recommended in complicated cases.

Compartmental location of middle ear inflammatory polyps in cats: 9 cases (2021-2023)

OBJECTIVES

To report the compartmental location of feline aural inflammatory polyps within the tympanic bulla.

MATERIALS AND METHODS

Nine client-owned cats with clinical signs and middle ear filling consistent with feline aural inflammatory polyps were prospectively pre-selected and underwent unilateral or bilateral ventral bulla osteotomy. Preoperative and surgical findings, complications and outcomes were recorded. Tissues obtained from the ventromedial compartment and from the dorsolateral compartment of the tympanic bulla were submitted separately for histological examination. Definitively selected cats were those having feline aural inflammatory polyps in at least one compartment of their operated tympanic bulla.

RESULTS

Ten ventral bulla osteotomies were performed on nine cats. Feline aural inflammatory polyps were histologically diagnosed in both compartments of all tympanic bullas. There were no intraoperative complications. Apart from Horner's syndrome on the ipsilateral eye following surgeries, post-operative complications were rare. This is the first study that documents the presence of feline aural inflammatory polyps in both compartments of the tympanic bulla in all cats with aural involvement.

CLINICAL SIGNIFICANCE

Should a complete excision of feline aural inflammatory polyps be desired, complete debridement of both compartments of the tympanic bulla is required. Traction-avulsion techniques using approaches of tympanic bulla with no visit of the ventromedial compartment may not completely resolve the condition.

Case report: Combination technique of balloon dilation, membrane excision, and topical mitomycin C for the treatment of nasopharyngeal stenosis in a cat

A two-year-old neutered male Turkish Angora cat presented with respiratory signs, including chronic snoring sounds and dyspnea with open-mouth breathing. Nasopharyngeal stenosis (NPS) was diagnosed based on endoscopy and computed tomography (CT). An attempt was made to break down the membrane, causing stenosis in the nasopharynx through balloon dilation using a valvuloplasty balloon dilation catheter (12 mm × 3 cm) and retroflexed endoscope. The balloon size was selected according to the identified diameter of the stenotic site on nasopharyngeal CT images. The balloon was inflated with radiographic contrast medium and maintained for 2 min; the similar procedure was repeated four additional times. The stenotic membrane was excised after balloon dilation. Topical Mitomycin C (MMC) was then administered to the stenotic region. After 2 weeks, an additional MMC application was repeated to prevent recurrence. The cat remained free of clinical signs without recurrence for 12 months after the most recent procedure. In this study, effective treatment results were obtained using a combination of balloon dilation, membrane excision, and topical MMC for membranous nasopharyngeal stenosis in a cat.

Comparative performance of video-otoscopy and CT in the diagnosis of external ear disease in cats

OBJECTIVES

The aim of the study was to compare CT with video-otoscopy for detecting external ear canal masses in cats and to describe CT features of feline external ear disease.

METHODS

This retrospective study evaluated the external ear canals of cats that underwent both CT and video-otoscopy. Two blinded observers reviewed the CT scans and their findings were compared with video-otoscopy results evaluated by one blinded observer.

RESULTS

Of the 32 examined ears, 13 had an external ear canal mass detected by both CT and video-otoscopy. No false positives were identified. All 19 ears without masses were correctly identified as true negatives, resulting in perfect agreement for mass detection (kappa = 1.000). On histopathology, 9/13 masses were diagnosed as polyps, 1/13 masses was diagnosed as carcinoma, 2/13 did not undergo histopathology and 1/13 masses seen on video-otoscopy was diagnosed as otitis externa with granulomatous tissue formation. Of the 16 cats examined, 12 had a mass in the external ear canal diagnosed by video-otoscopy: six domestic shorthairs, five Maine Coons and one Oriental Shorthair cat. Of these cats, 11 had a unilateral mass and one had a bilateral mass. There was very low agreement between CT and video-otoscopy for ear canal wall enhancement and erythema (kappa = 0.033), as well as for ear canal thickening and stenosis (weighted kappa = 0.056). There was no significant difference between chronic and non-chronic clinical signs in terms of the presence of ear canal wall mineralisation (P = 0.223).

CONCLUSIONS AND RELEVANCE

There is high agreement between video-otoscopy and CT in detecting external ear canal masses in cats. However, there is very low agreement between CT and video-otoscopy for ear canal wall enhancement, erythema, thickening and stenosis. The presence of external ear canal mineralisation did not correlate with the chronicity of clinical signs.

Pseudomonas aestus Isolation from the Nasal Cavity of a Cat with Chronic Rhinitis

The Pseudomonas genus includes ubiquitous bacteria frequently described as animal and human opportunistic pathogens. A 9-year-old cat was referred for rhinoscopy at the Veterinary Hospital of the Faculty of Veterinary Medicine, University of Lisbon, Portugal, for an investigation of the chronic respiratory signs. Upon rhinoscopy, nasal and nasopharyngeal discharge were observed, and the nasal turbinates showed signs of inflammation. The nasal biopsies were evaluated by histopathology and mycological and bacterial cultures. The histopathology revealed chronic lymphoplasmacytic inflammation. The mycological culture was negative, but the bacterial culture revealed the growth of a bacterial isolate in the pure culture, identified as P. aestus by the sequencing of a 1750 bp PCR amplicon obtained with BCR1 and BCR2 primers, followed by homologous sequences analysis using the NCBI database. The isolate's susceptibility profile towards 14 antimicrobials was evaluated through the disk diffusion method, being observed that it presented a multidrug resistance profile. The studies available on this environmental Pseudomonas strain focused on its potential use for biocide production and application in agricultural settings, and, to the authors' best knowledge, there are no reports describing its association with infectious diseases in humans or animals, highlighting the importance of establishing protocols aiming at the identification and characterization of non-traditional, multidrug-resistant Pseudomonas in the clinical setting.

Retrospective study of 540 cats with respiratory diseases in Japan (2003-2020)

BACKGROUND

Few epidemiological studies on respiratory medicine and the relationship between clinical signs and various respiratory diseases in cats have been reported.

OBJECTIVES

This retrospective study aimed to investigate the prevalence and breed predisposition to feline respiratory diseases in Japan and determine the association between clinical signs, duration and type of respiratory diseases.

METHODS

The medical records of cats with feline respiratory diseases were examined to obtain information on age, sex, breed, final diagnosis, clinical signs and duration. The odds ratios (ORs) and 95% confidence intervals were calculated to evaluate breed predispositions. Mann-Whitney U, Kruskal-Wallis and Dunn's tests were used to assess the duration of clinical signs.

RESULTS

This study included 540 cats with 615 respiratory diagnoses. The American Shorthair breed was predisposed to bronchopneumonia (BP; OR: 5.0) and pulmonary tumour (PT; OR: 3.6), while the Russian Blue breed exhibited a predisposition to inflammatory lower airway diseases (OR: 3.4), BP (OR: 6.1) and interstitial lung diseases (OR: 11.1). Similarly, the Scottish Fold breed displayed predisposition to PTs (OR: 5.8). The duration of clinical signs among nasal diseases, nasopharyngeal diseases and lower tracheal/bronchial and pulmonary diseases differed significantly (p = 0.001, p = 0.012, p < 0.0001, respectively).

CONCLUSIONS

The results suggest that some popular breeds in Japan are predisposed to feline respiratory diseases, especially the American Shorthair, Russian Blue and Scottish Fold breeds. The characteristics of occurrence, clinical signs and duration of each disease will aid in diagnosing, treating, preventing and elucidating the pathophysiology of feline respiratory disease.

Feline lymphoplasmacytic rhinitis (FLPCR): Severity of inflammation correlates with reduced mucosal IgA expression

Feline lymphoplasmacytic rhinitis (FLPCR) is a rare disease with an unclear pathogenesis characterized by lymphoplasmacytic (LPC) inflammation and progressive tissue destruction. Aims were to evaluate specific FLPCR clinical and pathological features to gain insights into disease pathogenesis. Signalment, clinical signs, serology and 47 pin. h biopsies were retrospectively collected from 33 FLPCR and 3 normal cats. Microscopical lesions and immunohistochemistry results utilizing anti-CD3, anti-CD20, anti-FOXP3, anti-feline-IgA, IgG, IgE and anti-FeLV (p27 and gp70), FIV, FCV and, FHV were scored and most were analyzed statistically. The majority of cats were domestic short haired (26/31) with median age of 11 years and a 0.35 F/M ratio. Serology evidenced 3/22 FIV and 1/22 FeLV positive cats. Immunohistochemistry evidenced 1/33 FeLV-p27 positive cats. Common clinical signs were sneezing (19/24 [79 %]), mucous discharge (13/24 [54 %]) and stertor (10/24 [42 %]). In normal tissues, IgAs were expressed in mucin, apical and lateral cell membrane of columnar cells and in periglandular plasma cells. IgGs were expressed in 20-30 % of columnar cells. Number of clinical signs was statistically significantly higher in female cats (p < 0.0001) and was significantly correlated with chronicity (p = 0.004), and IgG scores (p = 0.01). LPC severity scores correlated positively with infiltration of neutrophils (p = 0.015), gland destruction (p = 0.019) and angiogenesis (p = 0.016) and negatively with fibrosis (p < 0.0001). LPC severity scores were also significantly associated to female sex (p = 0.01) and to IgA (p = 0.03), with higher IgA scores associated to lower LPC scores. FLPCR associated to disruption of mucosal defense mechanisms generating cycles of tissue inflammation, tissue damage and repair with progressive loss of function independent from viral infections.

Feline bilateral inflammatory aural polyps: a descriptive retrospective study

BACKGROUND

Feline inflammatory aural polyps (IP) have been reported as solitary growths, yet bilateral polyps may occur more commonly than described previously.

OBJECTIVES

To identify the prevalence and risk factors associated with bilateral feline IP within a population of cats evaluated at a veterinary teaching hospital over a 10 year period.

ANIMALS

Twenty-five cats with histologically confirmed IP.

METHODS AND MATERIALS

A retrospective study was performed by searching computerized medical records of cats seen at The University of Tennessee Veterinary Teaching Hospital from 2005 to 2015. Keywords used for the search included "feline polyp", "ventral bulla osteotomy", "inflammatory polyp ear canal" and "nasopharyngeal polyp".

RESULTS

Cats were separated into groups with unilateral or bilateral disease. Six of 25 (24%) cats had bilateral IP. Twelve cats had computed tomography performed (four of six with bilateral IP; eight of 19 with unilateral IP). Clinical signs, history of upper respiratory infection, post-treatment complications, and IP recurrence with and without local and systemic steroid administration were studied between groups and no differences were identified. In four of six cats with bilateral disease, the second polyp was identified with advanced imaging performed at the time of referral.

CONCLUSIONS AND CLINICAL IMPORTANCE

These findings demonstrate that bilateral IP occur more frequently than reported previously and establish a prevalence for bilateral IP. These findings also highlight the value of advanced imaging techniques in diagnosing bilateral IP.

A retrospective study of more than 400 feline nasal biopsy samples in the UK (2006-2013)

OBJECTIVES

The main objective of this study was to utilise a large database from a UK-based, commercial veterinary diagnostic laboratory to ascertain the prevalence of different forms of nasal disease within the feline population. Further objectives included using this database to detect any breed, sex or age predilections, or associations between the degree of brachycephalism, and the different conditions diagnosed.

METHODS

Records from the laboratory were searched for feline submissions received between 31 May 2006 and 31 October 2013. For all samples taken from the nasal cavity, the diagnosis was recorded together with the breed, age, sex and neuter status of the cat, whether the clinical presentation was uni- or bilateral and whether a nasal discharge was present. Pedigree breeds were further subclassified according to skull conformation into brachycephalic, mesocephalic and dolichocephalic. Logistic regression models were constructed to assess the adjusted magnitude of association of significant risk factors with each disease, and each disease was also used as a potential independent risk factor for each other disease.

RESULTS

The most prevalent nasal disease was rhinitis, followed by neoplasia and polyps. The most commonly diagnosed neoplasm was lymphoma, followed by adenocarcinoma and undifferentiated carcinoma, with benign tumours being very uncommon. No significant association was found between skull conformation and nasal diseases. The only statistically significant association was polyps being more likely to arise in younger male cats, with a mesocephalic skull conformation and no nasal discharge.

CONCLUSIONS AND RELEVANCE

No significant association was found between skull conformation and nasal diseases, contrary to what might be expected. The only significant association found between any of the potential risk factors and various forms of nasal disease was polyps being more likely to arise in younger cats; other identified associations are only likely to be weak.

Dynamic pharyngeal collapse in three cats with different pharyngeal pathology

Dynamic pharyngeal collapse (PC) is a rarely reported condition in cats defined as the partial or complete collapse of the pharyngeal lumen during inspiration. Herein, we report the imaging findings and clinical features of three cats with dynamic PC. Lateral radiograph of the head was insufficient to detect dynamic PC, but fluoroscopy in conscious cats revealed dynamic PC. Magnetic resonance imaging was not helpful to reveal dynamic PC and underlying diseases. We obtained biopsy samples from the irregular nasopharyngeal mucosal membrane through endoscopy in two of the three cases and high-grade B-cell lymphoma was histopathologically diagnosed. In feline cases with abnormal upper respiratory sounds, dynamic PC should be considered, and fluoroscopy is the imaging technique of choice to diagnose the condition.

Cryptococcal nasopharyngeal polypoid mass in a cat

Case summary

An indoor 9-year-old castrated male domestic cat was referred with a 4 month history of increased upper airway noise. Computed tomography revealed a nasopharyngeal polypoid mass, which was removed endoscopically with basket forceps. Histopathology was compatible with a polypoid granulomatous pharyngitis with Cryptococcus-like organisms. This was supported by a positive serum latex cryptococcal antigen agglutination test (LCAT). Minimal inflammation of the nasal tissue was noted on histopathology, with no evidence of fungus. Following endoscopic removal of the mass, the patient was treated with systemic antifungal medication (itraconazole). One year after diagnosis, the LCAT titer was negative and the cat remained free of clinical signs.

Relevance and novel information

This case report emphasizes the importance of considering Cryptococcus species as a potential etiology in cats presented with signs of nasopharyngeal obstruction with an isolated nasopharyngeal polypoid mass, even if kept indoors.

Treatment of acquired nasopharyngeal stenosis using a removable silicone stent

The aim of this prospective study was to characterise patient characteristics and the histories of cats with acquired nasopharyngeal stenosis (ANS), and to describe the use of a removable silicone stent for treatment. ANS was diagnosed in 15 cats with clinical signs present for a median of 4 months. Clinical signs included stertor and inspiratory difficulty, nasal discharge, sneezing, dysphagia, regurgitation, vomiting and anorexia. Radiographs revealed a dorsal deviation or deformation of the caudal part of the soft palate in 10 of the cats, a soft tissue density across the cranial nasopharynx in four and no abnormality in one. The stenosis was initially dilated with a Kelly forceps in 10 of the cats and by balloon dilatation in five. A segment of a 24 Fr silicone thoracic catheter was used for the stent in five cats; in the other 10 cats a segment of a 28 Fr catheter was used. The stent was removed after 3 weeks in 12 cats and after 4 weeks in the other three. Endoscopy revealed an adequate nasopharyngeal diameter in all of the cats. At both 3 and 10 months after surgery the response was considered to be satisfactory, with complete resolution of clinical signs in 14 cats and improvement in the remaining cat. The treatment of ANS by stenosis dilatation followed by temporary stenting with a silicone stent is a rapid, safe, economical and effective procedure.