Feline heartworm disease and environmental allergens hypersensitivity: is there a link?

Abstract

Feline heartworm (Dirofilaria immitis) is often confused with other respiratory pathologies that are very common in daily clinical practice, such as feline asthma or chronic bronchitis. Furthermore, the relationship between bronchoconstriction and bronchospasm in cats and the presence of anti-D. immitis IgG has been previously described in other studies. Also, studies in humans and other species have shown correlations between nematodes and allergy. The objective was to determine whether cats with respiratory symptomatology that presented Heartworm Associated Respiratory Disease (HARD) or heartworm disease (HWD) were more hypersensitive to certain environmental allergens than cats that had not been previously exposed to D. immitis. Taking into consideration age, sex, breed and clinical history, 72 feline serum samples were evaluated for the presence of anti-D. immitis antibodies by indirect ELISA. Then, the samples were tested for specific IgE against different environmental allergens. The results showed that there were no significant differences between the presence or absence of symptoms and the ELISA results. On the other hand, of the 43 ELISA-positive cats, 69.8% were allergic and of the 29 seronegative cats, only 24.1% were allergic. Therefore, a relationship between seropositivity to D. immitis IgG and the presence of environmental IgE could be demonstrated, as ELISA-positive cats were three times more allergic than ELISA-negative cats.