Early bactericidal activity of amoxicillin in combination with clavulanic acid in patients with sputum smear-positive pulmonary tuberculosis

The early bactericidal activity (EBA) of an antituberculosis agent is the r ate of decrease in viable colony-forming units (CFU) per milliliter of sput um during the first 2 d of treatment of patients with previously untreated smear-positive pulmonary tuberculosis. The objective of this open randomize d study was to evaluate the EBA of the combination of amoxicillin 3 g and c lavulanic acid 750 mg. Ten patients with a mean age of 34 y and a mean weig ht of 56 kg received amoxicillin/clavulanic acid and 5 patients with a mean age of 34 y and a mean weight of 57 kg received no drug, In the patients r eceiving I dose of amoxicillin/clavulanic acid daily for 2 d the mean log(1 0)CFU/ml of sputum before treatment mas 6.7402 (SD 0.539) and after 2 d of treatment 6.7046 (SD 0.609); the corresponding values in patients receiving no drug vc-ere 6.7823 (SD 0.563) and 6.7502 (SD 0.673), respectively. The EBA of 0.018 (SD 0.130) in patients receiving amoxicillin/clavulanic acid d id not differ significantly from that of 0.016 (SD 0.069) in patients recei ving no drug. It is unlikely that the combination of amoxicillin/clavulanic acid has an important place in the treatment of tuberculosis with the exce ption of those patients with multidrug-resistant tuberculosis who are other wise therapeutically destitute.