Retrospective prevalence and incidence of drug-induced agranulocytosis in the city of São Paulo-Brasil.

Retrospective study carried out in São Paulo, Brazil, from September 1981 through March 1990. During this period the study investigated 19,389 hematological patients, aiming to assess the prevalence and estimate the incidence of drug-induced agranulocytosis. To assess the Hematology Center's catch population, where the study took place, we adopted the incidence of hemophilia A, chronic myeloid leukemia and acute leukemia, described by the international literature as reference for our catch population estimate. Our findings revealed a prevalence of 1 case of agranulocytosis per 3,878 subjects treated at the São Paulo Hematology Center which translates into an incidence of 0.44 to 0.82 cases of agranulocytosis per million inhabitants, per year.