Jellybean: A “Nose-Worthy” Patient
Nasal discharge in a kitten is a typical presentation at any veterinary hospital, but Jellybean, the 7-month-old neutered male Scottish Fold kitten, was anything but typical.
Jellybean presented to Dr. Susan Kimmel, DVM, DACVIM-SAIM, MD (Internal Medicine) at VCA Veterinary Referral & Emergency Center of Westbury for a chronic history of nasal discharge ever since he was obtained by the owners at 10 weeks of age. He occasionally had stertorous breathing and would often open-mouth breathe after exerting himself. His referring veterinarian had trialed antibiotics, changing the nasal discharge from thick and green to clear, but his signs did not resolve.
Because of Jellybean’s young age, viral and infectious causes were considered most likely, although other differentials, such as a foreign body, were considered. Neoplasia and fungal rhinitis could not be ruled out but were considered much less likely.
Due to financial constraints, a CT scan was not performed first, and the owners opted to proceed with a diagnostic rhinoscopy.
Upon retroflex visualization of the nasopharynx with a flexible video bronchoscope, the area of the choanae could be well visualized. The right side (seen as the left side on Figure 1) appeared to be covered by an imperforate, smooth-surfaced web of tissue with no apparent patent opening compared to the left.
Under endoscopic visualization, the webbing was cleared with balloon dilation. First, a 3.5 Fr Tomcat catheter was advanced antegrade from the right nares until it was visualized pushing caudally on the rostral side of the web, when viewed from the nasopharynx. The catheter was then used to pierce through the abnormal tissue (Figure 1). Using this newly formed small foramen, a dilation procedure was performed using an 8-10mm balloon dilation catheter, which was advanced antegrade through the area of webbing and stenosis. The area of the webbing was also biopsied.
Following dilation and biopsy, an expected amount of erythema and bleeding was observed. An intact and relatively normal-appearing choanal opening could now be seen bilaterally (Figure 2).
After the procedure, Jellybean was immediately breathing more normally, with reduction in stertor. Results from the biopsy samples revealed chronic active rhinitis, bacterial aerobic culture was negative and respiratory PCR was positive for Mycoplasma felis. Jellybean was treated with an initial dose of buprenorphine, a one-month weaning course of anti-inflammatory prednisolone and a 10-day course of azithromycin.
Several weeks after the procedure, Jellybean’s owners reported that he was still breathing easily, allowing him to play and enjoy the zoomies like a healthy kitten. Dr. Kimmel and her team continue to follow up into the future and are hopeful for lasting improvement.
Dr. Kimmel’s Key Takeaways
What Is Nasopharyngeal Stenosis and Webbing?
Nasopharyngeal stenosis and webbing is a relatively uncommon condition that is primarily diagnosed in young cats with a history of chronic rhinitis, which is often secondary to chronic viral and/or bacterial infections. Other causes include scar tissue from supra-esophageal gastric reflux, prior trauma or surgery. Congenital malformations have also been reported. Clinical signs are usually associated with the obstructive nature of the stenosis and webbing, with stertor, open-mouth breathing and often nasal discharge being noted.
How Can We Treat Nasopharyngeal Stenosis and Webbing?
Treatment has been reported with bougienage, catheter dilation using endoscopy or fluoroscopy guidance, surgery and stent placement. In Jellybean’s case, endoscopic balloon dilation was elected because it was readily available and could be performed under the same anesthetic episode as the diagnostic rhinoscopy. Balloon dilation is also advantageous because it’s relatively inexpensive, minimally invasive and does not result in a permanent foreign body (i.e., stent).
How Effective Is Balloon Dilation?
Similarly to other types of stenosis, scar tissue may re-form after dilation procedures, causing return of stenosis and webbing. In such cases, recurrence of clinical signs is typically observed within several weeks after the procedure, requiring additional dilation procedures. A different treatment (e.g., surgery, stenting) may be attempted to achieve a more permanent response. To reduce the rate of recurrence after dilation, medications that reduce fibrosis may be used, such as post-dilation instillation of an antifibrotic agent (e.g., mitomycin B) at the dilation site, injection of triamcinolone into the tissue or use of oral prednisolone therapy at anti-inflammatory doses for 4–6 weeks. Depending on the cause, use of antibiotics and antiviral therapies may also be warranted.
This case was presented by Dr. Susan Kimmel, DVM, DACVIM-SAIM at VCA Veterinary Referral & Emergency Center of Westbury.
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