Granulocytopenia in hospitalized patients: II. A prospective comparison of two antibiotic regimens in the empiric therapy of febrile patients

The results of empiric antibiotic therapy in 126 hospitalized patients with fever during 192 episodes of granulocytopenia were studied. Febrile granulocytopenic patients were randomly allocated to receive either carbenicillin, methicillin and gentamicin, or carbenicillin and cephalothin. The response rate for the two antibiotic regimens was similar, 49 (60 per cent) of 81 responded to the former and 42 (54 per cent) of 78 to the latter. The response rate in patients receiving other antibiotics because of specific indications or counterindications was 19 (58 per cent) of 33. Thirty-nine (35 per cent) of 110 patients who responded to initial antibiotic therapy had an increase in circulating granulocytes of one log₁₀ or more compared to only 10 (12 per cent) of 79 nonresponders with such an increase. The mortality rate in adult patients receiving carbenicillin, methicillin and gentamicin was eight (16 per cent) of 51, compared to 18 (37 per cent) of 49 in those receiving cephalothin and carbenicillin (P < 0.05). The significance of this difference in mortality rate is uncertain, as there was no difference in the initial response rate or mortality rate between patients treated with the two antibiotic regimens when only patients with documented bacterial infection were considered. Patients who responded to their initial antibiotic regimen, and patients for whose fever no explanation was found, had the best prognosis.