Comparative clinical evaluation of ceftriaxone in treating lower respiratory tract infections.

To evaluate the clinical and microbiological efficacy and safety of ceftriaxone in comparison with cefotaxime in treating acute lower respiratory tract infections two open randomized trials were performed. Sixty-two adult hospital in-patients were entered and 58 completed the study. The patients suffered from either acute (broncho-)pneumonia (19pts) or severe exacerbation of chronic bronchopneumonia (39 pts). Forty-one of the patients had severe underlying or concurrent diseases. Diagnoses were in all cases confirmed by isolation of the causative pathogen(s) from bronchial brushing or washing under fiberoptic bronchoscopy. Twenty-eight patients were administered at random with either a single 2g daily dose of ceftriaxone or 2g twice daily dose of cefotaxime (1st trial). Successively (2nd trial) ceftriaxone was administered at a dose of 1g once daily either i.v. or i.m. The duration of treatment ranged from 7 to 12 days. A satisfactory response was observed in all patients suffering from acute pneumonia or bronchopneumonia; the eradication rate of the causative pathogen was 73% and 62% for ceftriaxone and cefotaxime, respectively. Concerning the exacerbation of chronic bronchopneumonia (39 patients) an overall satisfactory response to both treatments was registered in about 80% of cases. No significant differences between the 1g and 2g single daily dosing regimens of ceftriaxone appeared. Both ceftriaxone and cefotaxime were well tolerated: no or minimal changes in laboratory values were noticed. It is concluded that a 1g or 2g single daily dose of ceftriaxone were at least as effective as a 2g twice daily dose of cefotaxime in treating acute lower respiratory tract infections due to susceptible pathogens.

Treatment of lower respiratory tract infections with ceftriaxone and cefotaxime. A comparative study.

The microbiological and clinico-therapeutic efficacy and safety of ceftriaxone were compared with those of cefotaxime in an open randomized trial. Fifty-four adult hospitalized patients (37 males and 17 females) suffering from either acute bronchopneumonia (19) or acute exacerbations of chronic bronchopneumonia (35) have been investigated. Four patients were withdrawn from the trial. Underlying diseases were present in 41 patients. Ceftriaxone was administered at a once-a-day dose of either 1 or 2 g (in 13 and 14 patients, respectively) and cefotaxime at a 2 g twice daily dosing regimen (27 patients), both antibiotics being given for 7-12 days. In the ceftriaxone group, 15 out of the 27 patients were cured (55%) and 9 had a favourable clinical response for a total satisfactory response rate of 88%. The causative pathogen was eliminated in 18 (66%) patients. The results obtained in the cefotaxime group did not differ significantly, but 2 patients were excluded from the study because of in vitro resistance of the causative pathogen isolated. Both drugs were well tolerated: no relevant laboratory changes were registered. The results indicate that ceftriaxone at a dosage of 2 or 1 g daily is at least as effective as cefotaxime given daily at a dosage of 4 g in the treatment of severe lower respiratory tract infections.

Clinical evaluation of netilmicin in the field of internal medicine.

An open clinical trial was carried out to evaluate therapeutic efficacy and safety of netilmicin. Forty hospitalized adult patients suffering from complicated urinary tract infections (UTI) (19), lower respiratory tract infections (20), septicemia (3) and soft tissue infection (1) due to in vitro susceptible microorganisms were admitted to the study. Twenty-nine of these patients had severe underlying diseases interfering with host defenses. Twenty-nine out of the 40 patients (73%) were cured and 6 (15%) had a favorable clinical response giving an overall satisfactory clinical response of 88%. Eradication of causative microorganisms was obtained in 29 (73%) patients, and three substitutions during or at the end of treatment were observed. Netilmicin was well tolerated: neither clinical abnormalities of otovestibular function nor hepatic or hematological alterations were found, while only two patients developed a mild and transient increase of BUN and creatinine serum levels.

In vitro antibacterial activity of imipenem against Pseudomonas and Staphylococcus species. Comparison with thirteen other antimicrobial agents.

The in vitro antimicrobial activity of imipenem against recent clinical isolates of Pseudomonas spp. (94 strains) and penicillin-resistant Staphylococcus spp. (50 Staph. aureus and 50 coagulase-negative Staphylococcus) was assessed using the Mueller-Hinton agar dilution method. Results were compared with those simultaneously obtained for amikacin, netilmicin, tobramycin, norfloxacin, piperacillin, ceftazidime, ceftriaxone and azthreonam against Pseudomonas spp., and for rifampicin, clindamycin, netilmicin and cefoxitin, besides penicillin and methacillin, against Staphylococcus spp. About 50 and 90% of 84 Pseudomonas aeruginosa isolates were inhibited by concentrations of imipenem equal to or less than 2 and 8 mg/l respectively. The in vitro activity of imipenem was comparable to that of ceftazidime and norfloxacin, but superior to that of the aminoglycosides and all the other antibiotics tested, in terms of potency by weight. Among other Pseudomonas spp. only P. malthophilia (2 strains) proved resistant to imipenem. Rifampicin was the most active antibiotic by weight against Staph. aureus but imipenem was more active than clindamycin and, especially, netilmicin and cefoxitin. Imipenem was highly active also against coagulase-negative staphylococci, with some differences related to the high incidence of methicillin-resistant strains. MICs of imipenem in Mueller-Hinton broth correlated with those obtained in agar, unlike the aminoglycosides. There were no significant inoculum effects on MICs of imipenem and MBCs were within one twofold dilution of MICs in over 75% of assays.

Preclinical comparative evaluation of aminoglycosides.

Five aminoglycoside antibiotics including gentamicin, sisomicin, tobramycin, amikacin and netilmicin were comparatively tested in vitro against 283 clinical isolates of Pseudomonas, Enterobacteriaceae and Gram-positive cocci, using the agar dilution technique according to I.C.S. recommendations. In respect to potency by weight, netilmicin proved the most active aminoglycoside against E. coli, K. pneumoniae, Enterobacter, Serratia spp. and Staphylococcus aureus, followed by sisomicin or tobramycin in relation to various bacterial species. Against Pseudomonas aeruginosa, sisomicin and tobramycin had the lowest MICs (minimum inhibitory concentrations). Amikacin had overall less activity but the widest spectrum. Rate of killing curves showed few differences among the aminoglycosides tested. Against gentamicin-resistant strains (MIC greater than or equal to 16 micrograms/ml) the activity of netilmicin was comparable to or higher than that of amikacin, except for P. aeruginosa, P. cepacia and indole-positive Proteus, which were inhibited by amikacin only. Netilmicin also showed the highest "therapeutical index" calculated as the ratio between MIC and blood levels for each aminoglycoside against each most important bacterial specie.

[Classification of acute bacterial enteropathies]. / Inquadramento e classificazione delle enteropatie batteriche acute.

The first part considers pathogenic microorganisms (Vibrio cholerae and parahaemolytic vibrio, Clostridium welchii, enteropathogenic E. coli, Shigella, Salmonella, other enterobacteria and pseudomonas. Yersinia, simply enterotoxic Staphylococcus and that producing acute enteritis) and the process of infection (formation of a surface link without endocellular penetration with elaboration of hexotoxins, formation of a surface link with subsequent intracellular penetration, submucosa penetration). The second part discusses Salmonellae on the basis of personal experience. Particular attention is paid to current aspects of Salmonella microbiological pathomorphosis, the various isolated serotypes in relation to carriers or patients, biochemical atypias of Salmonellae strains, present-day aspects of resistance to chemoantibiotic treatment and the transfer of Salmonella Wien resistances.

Clinical evaluation of tobramycin in respiratory and systemic infections in immunodepressed and normal patients.

Twelve patients with acute or chronic pneumonia due mainly to gram-negative bacilli, two patients with pseudomonas endocarditis, and two patients with seratia sepsis were treated with 80-160 mg of tobramycin in two daily doses. Fourteen infected patients with underlying leukemia or lymphoma received this dose of tobramycin combined with cefazolin or penicillin. Most respiratory infections were cured or markedly improved. with eradication or significant reduction in the number of infecting organisms. One case of pseudomonas endocarditis and both cases of serratia sepsis were also cured. Combined treatment with tobramycin and beta-lactam antibiotics resulted in clinical and bacteriological improvement in 50% of systemic immunodepressed patients with sepsis and/or pneumonia.