BRONCHIAL CASTS IN CHILDREN - A PROPOSED CLASSIFICATION BASED ON 9 CASES AND A REVIEW OF THE LITERATURE

Bronchial casts are characterized by the formation of obstructive airw ay plugs that may be large enough to fill the branching pattern of an entire lung. The condition is rare but can occur at any age. Casts may be secondary to underlying diseases such as asthma and cystic fibrosi s, but there are often no predisposing factors. There is no accepted c lassification system for bronchial casts; but only a confusion of desc riptive terms such as mucoid impaction, fibrinous bronchitis, and pseu domembranous bronchitis. Based on a review of nine well-documented cas es and the available literature, we have separated bronchial casts int o two well-defined groups: Type 1 (inflammatory), consisting of casts composed mainly of fibrin with a dense eosinophilic inflammatory infil trate; and Type 2 (acellular), consisting of casts composed mainly of mucin with little or no cellular infiltrate and occurring only in chil dren with congenital cyanotic heart disease. Acute mortality was high in both groups. Survivors of Type 1 casts seem to be well controlled w ith inhaled steroids. Optimal therapy for patients with Type 2 casts i s not clear; the prognosis probably depends on underlying cardiac stat us. We hope that this simple classification will provide a framework f or further study of this obscure condition.