In a recent discussion1 of the allergic pulmonary reactions of Loeffler's syndrome it was recognized that this syndrome may occur under many allergic conditions. In a paper on the morphologic similarities of the lesions, presumably allergic in nature, of rheumatic fever, periarteritis nodosa and "other allergic syndromes" Bergstrand2 adopts the explanation that the lesions in the joints, the heart, the blood vessels, the skin and other structures of rheumatic fever are caused by allergic reactions in which the antigen is derived from hemolytic streptococci. The vascular lesions may be much like those in periarteritis nodosa, and more or less transient lung infiltrations with eosinophilia occur in rheumatic fever.
As for periarteritis nodosa, there is direct experimental evidence of its allergic nature. Bergstrand describes 4 cases of asthma with typical transient pulmonary infiltrations, abdominal pain, diarrhea and nasal polyps, but the asthmatic features were the most conspicuous. Besides the
ALLERGY IN THE PRODUCTION OF LESIONS IN DISEASE. JAMA. 1947;133(11):776. doi:10.1001/jama.1947.02880110042013