[Recurrent eosinophilic pneumonia. Bibliographical review, nosographic, pathogenetic and unitary setting reflections on the disease].

The literature on the pathological conditions inherent in pulmonary eosinophilias is reviewed from the earliest clinical and radiological observations to the most recent studies on eosinophil function. A case of recurring eosinophilic pneumonia is considered. This is a pathological condition that differs both from Löffler's transient infiltrate, being longer lasting, and from chronic eosinophilic pneumonia due to the lack of symptoms and moderate eosinophilia. On the basis of the existence of progressively deteriorating pictures whose aetiopathogenesis is still uncertain but which is certainly immunological and inflammatory in character given the involvement of eosinophils, the presence of characteristic radiological pictures and the response to steroid treatment, it is therefore agreed that these various pathological conditions constitute a single disease whose more benign extreme is represented by the reported case of recurring eosinophilic pneumonia, its more severe extreme by forms presenting high levels of circulating eosinophils, hypereosinophilia, a prolonged course and more marked symptoms typified by the disseminated eosinophilic collagen disease reported by Dell'Acqua and Mori.