In vitro and in vivo activity of piperacillin, a new broad-spectrum semisynthetic penicillin.

Abstract

Piperacillin sodium is a novel semisynthetic penicillin with broad spectrum activity against Gram-negative and-positive bacteria including anaerobes. In agar dilution tests with 522 clinical isolates, it inhibited at least 70-90% of each group of organisms at 16 meg/ml with the exception of the Serratia group which required 64 mcg/ml to inhibit 70 % of the isolates. Piperacillin was more potent than carbenicillin, ticarcillin and ampicillin against Klebsiella, Pseudomonas, Enterobacter and Serratia. Against Gram-positive cocci it was generally comparable to carbenicillin and ticarcillin except in the case of enterococci where it was significantly more potent. Piperacillin exhibited a broader spectrum than the cephalosporins which lacked antipseudomonal activity. It was more potent than cephalothin, cefamandole and cefoxitin against indole-positive Proteus, Acinetobacter and enterococci. Piperacillin is bactericidal; minimal bactericidal concentrations were within four-fold of the minimal inhibitory concentrations. Its activity was not significantly altered by pH, media or serum, but was reduced when inoculum size was increased from 10' to 10' CFU/ml. Synergistic effects were observed when piperacillin was combined with gentamicin or amikacin. Piperacillin was effective against both acute lethal infections and chronic kidney infections in mice. Our results indicate that piperacillin has a spectrum of activity that spans those of other semisynthetic penicillins and cephalosporins.

Clinical evaluation of the therapeutic efficacy and tolerability of piperacillin

“…In vitro studies have shown the effectiveness of piperacillin against many pathogens including P. aeruginosa, E. coli, Klebsiella sp., other members of Enterobacteriaceae, and Bacteroides spp. (2,6,7,9). The results of the present study generally agree with these reports.…”

“…Piperacillin, a new semisynthetic penicillin with a broad spectrum of activity against both gram-positive and gram-negative pathogens (2)(3)(4)(5)(6)(7)(8)(9)(10), is currently undergoing clinical evaluations for efficacy and tolerability in a number of institutions. The present report summarizes the current results of one such investigation.…”

Piperacillin susceptibility tests by the single-disk agar diffusion technique

“…It is particularly active against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Streptococcus faecalis (3,(5)(6)(7)12).…”

“…Studies Piperacillin is a new semisynthetic penicillin with in vitro activity significantly greater than that of either carbenicillin or ticarcillin (3, 5-7, 10, 12). It is particularly active against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Streptococcus faecalis (3,(5)(6)(7)12 …”

Beta-Lactam Antibiotics

“…Piperacillin displays activity in vitro against a wide range of Gram-negative and Gram-positive bacteria as well as anaerobes (7,8,9,10,11,12,13). This group includes the clinically established carbenicillin and ticarcillin, and the newer acyl-ureidopenicillins, azlocillin, mezocillin, piperacillin and furazlocillin (Bay K 4999).…”