Feline Asthma

Introduction

Asthma may be defined as an obstructive, reversible disease that affects the lower respiratory tract. It is characterized by bronchial hyper-reaction that causes a reduction in the bronchial diameter and an excessive mucous secretion which results in a variety of signs, including coughing, wheezing and respiratory distress. It is a rare condition in the animal kingdom that has only been described with these characteristics in the feline and human species (1).

First recognized in 1906 (2), asthma is one of the most common lung diseases in cats with considerable morbidity and eventual mortality. This respiratory condition has been given various names: lower airway feline disease, allergic feline asthma, allergic acute bronchitis, immune-mediated lower respiratory tract disease and feline bronchial disease. In any case, it must be clear that feline asthma is caused by an exaggerated immune reaction towards an inhaled allergen that generates specific chemical and structural changes in the tracheo-bronchial tree. Clinically, feline asthma is evidenced by the relatively variable presence of coughing, wheezing, exercise intolerance and respiratory distress that can settle spontaneously or in response to medical treatment (1,3,4).

This article aims at reviewing current knowledge on the pathophysiology of asthma in cats, recognizing the most frequent clinical signs and available diagnostic methods, and addressing a practical approach for the treatment and management of these cases. [...]

Key Points

• Feline asthma is an inflammatory disease that affects the lower respiratory tract and is characterized by bronchial hyper-reaction to different stimuli
• The reduction in air flow is typically the result of a combination of inflammation, mucous accumulation, and the contraction of airway smooth muscle
• Typical signs include coughing, wheezing, distress, orthopnea, tachypnea, and dyspnea with an excessive expiratory effort. Clinical signs may be permanent or intermittent, mild, moderate or severe
• The treatment for asthma as a disease must be focused on the control of inflammation in order to prevent bronchoconstriction
• Inhalation therapy is considered a key solution for human asthma management and nowadays it is widely recommended to treat feline asthma
• Alternative therapies that may be beneficial to manage feline asthma are available, but more investigation is required in order to prove their efficacy