Hemolytic Anemia Caused By Penicillin

To the Editor:—  In the article "Hemolytic Anemia Caused by Penicillin" by Nesmith and Davis (203:27), 1968), the authors reach the conclusion that since the cephalothin-treated autologous erythrocyte⁵¹Cr half-life was shortened in their patient with antipenicillin antibodies these antibodies caused hemolysis of both penicillin and cephalothin-treated erythrocytes. The interpretation of the results of their survival data are open to question since they do not provide data on the survival of cephalothintreated erythrocytes in normal individuals without antibodies.In a recent report, Molthan et al¹ noted that exposure of washed packed red blood cells to 50 mg/ml of cephalothin at 37 C for three hours produced a reduction of 54% in the hematocrit reading in vitro due to hemolysis. Nesmith and Davis incubated whole blood with cephalothin at a concentration of 25 mg/ml for 90 minutes, including the 30-minute incubation period with⁵¹Cr. It appears likely that