Taken together, these data support the hypothesis that transfusion of > or = 3 units of allogeneic RBCs is associated with early postoperative lymphopenia in otherwise healthy individuals undergoing surgery. These findings were not observed in those individuals transfused with RBCs that had undergone prestorage WBC reduction.

Agranulocytosis seems to be very rare in Latin America. The lower than expected number of cases identified during the study period precluded estimation of the risk associated to individual drugs, with the exception of methimazol. However, this is the longest series of agranulocytosis cases ever gathered in Latin America, and information on drug exposures was collected prospectively. The conclusion is that drug-induced agranulocytosis does not seem to be a major public health problem in the study regions.

The association of agranulocytosis with the use of many different drugs has been documented. LATIN is a case-control study designed to identify risk factors for agranulocytosis and aplastic anemia, including drugs, and to estimate the incidence rates of both diseases in some Latin American countries. This report will cover just agranulocytosis. In 4 years, 52 cases of agranulocytosis were diagnosed. The overall incidence rate was 0.38 cases per 1 million inhabitant-years (0.35 for Brazil, 2.09 for Argentina, and no case verified in Monterrey, Mexico). Agranulocytosis patients more often took medications already associated with agranulocytosis than controls (76.7% of cases and 52.5% of controls; OR 3.7, 95% CI 1.3–12.5; p = 0.01), the most important being methimazole (OR 44.2, 95% CI 6.8 to infinite). The population attributable risk percent (etiologic fraction) was 56%. The use of nutrients supplements was more frequent among agranulocytosis patients than controls (p = 0.03). The agranulocytosis incidence in Latin America was lower than that of European countries and Israel. The rarity of the disease indicates that it is not a public health problem, and there is no reason for major protection measures other than improving diagnostic tools and making earlier agranulocytosis diagnosis.

Aplastic anemia and agranulocytosis are rare diseases in Brazil. However, there is considerable variability in their incidences between different regions.