BackgroundAssociations between aplastic anemia and numerous drugs, pesticides and chemicals have been reported. However, at least 50% of the etiology of aplastic anemia remains unexplained.

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.

A patient presenting with a cervix uteri epidermoid carcinoma had acute renal failure after treatment with cisplatin and bleomycin. She later developed fatal bleomycin-induced pneumonitis and Stevens-Johnson syndrome. This is a very rare association of adverse effects. The risk of causing a drug interaction thus increasing the severity of bleomycin undesired effects must be taken into account when a nephrotoxic drug is added to the former. The authors stress the importance of monitoring renal function under these conditions.

In order to avoid gentamicin toxicity trough serum concentrations when drug monitoring is not available, a correction factor for serum creatinine was calculated and evaluated. In a first group of 35 patients under aminoglycoside treatment with variable serum creatinine (SCr) values, the regression plot of SCr concentrations versus half-life (T_½) values was established: log T_½ = log 2.28 + 1.45 log SCr, r = 0.90, p < 0.01. A second group of 18 patients was treated with doses of 1.0 mg/kg of gentamicin. Dose intervals equivalent to 3 T_½ were daily adjusted. The T_½ was calculated from SCr according to the relationship established for the patients of the first group. All the patients studied maintained trough levels within the therapeutic range.