Laryngeal Paralysis

The resultant partial or complete airway obstruction and respiratory distress may be observed as voice impairment (dysphonia), increased breathing noises during inhalation, exercise intolerance, fainting (syncope), and blue gums (cyanosis). The degree of respiratory distress is correlated to the number of nerves affected and whether the nerve is completely paralyzed or only partially impaired.

Compared to GOLPP, dogs affected by the RAPGEF6 variant are significantly younger (under two years of age). However, in the early stages of the disease, owners may easily miss the abnormally increased breathing sounds.

Diagnosis is made based on history and physical examination of the function of the larynx, which is typically performed with sedation.

Treatment is aimed at reducing episodes of respiratory distress and environmental modification. Some dogs may be candidates for the surgical opening of the larynx (often referred to as a “tie-back”), however, there is an increased risk of aspiration pneumonia after the procedure.

Talk to your vet about your dog’s laryngeal paralysis result so you can discuss how it may influence their daily activities and lifestyle.

Not all dogs with this result will show signs of disease. When symptoms do occur, they are typically seen in younger dogs, often around two years of age.

Avoid strenuous exercise, excitement, or exposure to heat and humidity, as these can make breathing more difficult. Keep your dog at a healthy weight and use a harness instead of a collar to avoid pressure on the throat.

Seek veterinary care immediately if your dog shows signs of respiratory distress, such as loud or labored breathing, coughing, or collapse.

Miniature Bull Terriers that have two copies of the variant have a 10- to 17-fold increased risk of developing LP compared to MBT with zero or one copy of the variant. However, not all dogs with two copies of this variant will go on to develop LP. This juvenile-onset form should not be confused with Geriatric Onset Laryngeal Paralysis Polyneuropathy (GOLPP) which occurs in middle-aged and older large and giant breed dogs and is supposed to be part of a generalized polyneuropathy.

Penetrance: Laryngeal Paralysis is recessive, that is, a dog requires two copies of the variant to show signs of the disease from the variant.

Gene

RAPGEF6

Inheritance type

recessive

Clinical category

Neuromuscular

Citations

1. Rasouliha et al 2019

• Bull Terrier
• Miniature Bull Terrier