Intravenous amoxicillin-sulbactam against Escherichia coli: optimizing the dose, component ratio and infusion time using a human pharmacodynamic model.

Amoxicillin-sulbactam (AMX-SUL) is an aminopenicillin/beta-lactamase inhibitor combination currently available in 29 countries which may be a suitable option for treating intra-abdominal infections. the aim of this study was to identify the optimal dose and ratio between components of this formulation through an ex-vivo human pharmacodynamic model against Escherichia coli. Four volunteers were randomized to receive alternatively a single dose of AMX-SUL infused either over 30 min or 3h in the following ratios (g/g): 1/0.5; 1/1, 2/0.5 and 0/2. time-kill studies were performed with the 0-, 0.5-, 2-, 4-, 6- and 8-h post-dosing sera against E. coli ATCC 25922 (AMX MIC, 2 microg/ml; AMX-SUL MIC, 2 microg/ml) and E. coli ATCC 35218 (AMX MIC, 1024 microg/ml; AMX-SUL MIC, 4-8 microg/ml). AMX-SUL 1g/0.5 g infused over 30 min was only active at 0.5 h after dose, being inferior to both AMX-SUL 1g/1g and AMX-SUL 2g/0.5 g against E. coli ATCC 25922, for which the 2h post-dose serum proved active. When tested against E. coli ATCC 35218, AMX-SUL 1g/0.5 g and AMX-SUL 2g/0.5 g were active only at 0.5 h post-dose, whereas AMX-SUL 1g/1g showed bactericidal activity 0.5h post-dose and was able to inhibit bacterial growth 2 h post-dose. When infused over 3h, the antimicrobial activity of AMX-SUL was better than the 30-min infusion. Moreover, AMX-SUL 1g/1g was able to inhibit, and kill to some extent, the E. coli ATCC 25922 strain at 4h post-dose (i.e. 67% and 50% of a 6- and 8-h dosing interval, respectively). The present study suggests that 1g/1g is the best formulation for AMX-SUL against E. coli. The infusion over 3h optimizes its pharmacodynamic profile, as well as that of the 1g/0.5g combination. These findings encourage the performance of clinical trials to assess the efficacy of this combination, given as an extended infusion, in the treatment of community-acquired intra-abdominal infections.

Comparative in vitro activity of tigecycline against bacteria recovered from clinical specimens in Latin America.

The present study was performed to evaluate the in vitro activity of tigecycline in comparison to other agents against isolates recovered from patients hospitalized in latin American. Organisms were collected in 47 clinical laboratories from 4 countries of latin America between November 2005 and October 2006 and were tested by using disk diffusion method as described by the CLSI. A total of 7966 isolates were assessed. Tigecycline proved highly active against staphylococci and enterococci (>99% susceptibility). Imipenem was the most active agent against Escherichia coli (100% susceptibility), followed by tigecycline, 98.6% susceptibility. Resistance to cefotaxime in this species was 15.3%. Global tigecycline susceptibility of Klebsiella species was 90.2%, but the susceptibility rate was significantly slower in Venezuela (82%) than in Argentina, Colombia and Chile (93%) (p<0.01). Global cefotaxime resistance to Klebsiella spp. was 32.2% and carbapenem resistance was detected in all countries. By adopting a susceptible breakpoint >or =16mm, 91.3% of the Acinetobacter isolates proved susceptible to tigecycline. Results from the present study suggest that tigecycline may be a suitable option in latin America, a region where multidrug resistance seems to be a dramatic, increasing problem and new antimicrobial choices are urgently needed.

Antimicrobial susceptibility of Staphylococcus aureus causing bovine mastitis in Argentine dairy herds.

We assessed the in vitro activity of selected antimicrobial agents against 95 Staphylococcus aureus strains causing both clinical and subclinical bovine mastitis belonging to 61 dairy farms from the Central dairy area of Argentina. Minimal inhibitory concentrations (MICs) of penicillin, oxacillin, gentamicin, erythromycin, enrofloxacin and florfenicol were estimated. In addition, the agar diffusion test was performed. MIC50 and MIC90 were as follows: penicillin, 0.05 and 4 microg/ml; oxacillin, 0.25 and 0.25 microg/ml; gentamicin, 0.25 and 0.5 microg/ml; erythromycin 0.125 and 0.25 microg/ml; enrofloxacin 0.25 and 0.5 microg/ml, and florfenicol 4 and 8 microg/ml. Beta-lactamase activity was detected in 89% of 46 penicillin-resistant strains. Apart from penicillin, antimicrobial resistance in S. aureus causing bovine mastitis remains rare in Argentine dairy farms.

Antimicrobial susceptibility of Staphylococcus aureus causing bovine mastitis in Argentine dairy herds / Sensibilidad a los antimicrobianos de Staphylococcus aureus causantes de mastitis bovina en rodeos lecheros de Argentina

We assessed the in vitro activity of selected antimicrobial agents against 95 Staphylococcus aureus strains causing both clinical and subclinical bovine mastitis belonging to 61 dairy farms from the Central dairy area of Argentina. Minimal inhibitory concentrations (MICs) of penicillin, oxacillin, gentamicin, erythromycin, enrofloxacin and florfenicol were estimated. In addition, the agar diffusion test was performed. MIC50 and MIC90 were as follows: penicillin, 0.05 and 4 µg/ml; oxacillin, 0.25 and 0.25 µg/ml; gentamicin, 0.25 and 0.5 µg/ml; erythromycin 0.125 and 0.25 µg/ml; enrofloxacin 0.25 and 0.5 µg/ml, and florfenicol 4 and 8 µg/ml. b-lactamase activity was detected in 89% of 46 penicillin- resistant strains. Apart from penicillin, antimicrobial resistance in S. aureus causing bovine mastitis remains rare in Argentine dairy farms.

Se evaluó la actividad in vitro de un grupo seleccionado de antimicrobianos contra 95 aislamientos de Staphylococcus aureus obtenidos de casos de mastitis bovina clínica y subclínica, en 61 rodeos lecheros de la cuenca central de Argentina. Fueron estimadas las concentraciones inhibitorias mínimas (CIM) de penicilina, oxacilina, gentamicina, eritromicina, enrofloxacina y florfenicol. Además se realizó la prueba de difusión en agar. Las CIM50 y CIM90 obtenidas fueron: penicilina 0,05 y 4 µg/ml; oxacilina 0,25 y 0,25 µg/ml; gentamicina 0,25 y 0,5 µg/ml; eritromicina 0,125 y 0,25 µg/ml; enrofloxacina 0,25 y 0,5 µg/ml y florfenicol 4 y 8 µg/ml. Se detectó actividad de b-lactamasa en el 89% de las cepas resistentes a la penicilina. A excepción de lo observado para penicilina, la resistencia a los antimicrobianos en S. aureus causantes de mastitis bovina en Argentina parece ser un fenómeno poco frecuente.

Comparative in vitro activity of tigecycline against aerobic and facultative isolates recovered from hospitalized patients: an Argentinean multicenter study.

Tigecycline, the 9-t-butylglycylamino derivative of minocycline is the first commercially available glycylcycline exhibiting an extended spectrum of antibacterial activity due to its capacity to evade the tetracycline ribosomal and efflux resistance mechanisms. We conducted a collaborative in vitro study determining the activity of tigecycline compared to 14 antimicrobials against clinically relevant isolates obtained from adult patients hospitalized in 9 Argentinean institutions. Minimum inhibitory concentrations (MICs) were determined by the reference broth microdilution method. The number of isolates and MICs 50/90 (mg/L) for tigecycline were the following: Acinetobacter spp. 132 (0.5/1); Escherichia coli 220 (0.12/0.25); Klebsiella spp. 220 (0.5/1), Enterobacter spp. 205 (0.5/1); Serratia spp. 84 (0.5/2); Haemophilus influenzae 96 (0.25/0.5); Staphylococcus aureus 223 (0.12/0.25); Streptococcus pneumoniae 98 (

Impact of antibiotic treatment on bacterial resistance rates from patients with hospital-acquired infection.

We assessed the impact of antibiotic administration prior to sample collection on the bacterial resistance rates from patients with nosocomial infection. Every individual susceptibility report was assessed in real time at the bedside of the patient by a team composed of infectious diseases and internal medicine specialists as well as clinical microbiologists for clinical significance and appropriateness of the specimen. The report also stated the kind, source and origin of the infection, history of administration of any antibiotic during the last month prior to sample collection. To evaluate the impact of previous antibiotic administration, resistance rates were calculated separately among the group of patients with and without history of antibiotic treatment. A crude univariate analysis was performed to assess the significance of the differences between groups for every species-antibiotic pair. Patients who had received ciprofloxacin showed significantly higher rates of Escherichia coli resistant to ciprofloxacin, broad-spectrum cephalosporins and gentamicin. A higher rate of methicillin-resistant Staphylococcus aureus was observed in patients who were given gentamicin. A stratified analysis showed that the previous antibiotic administration continued to be a risk factor for increased resistance rates regardless of the hospital ward or the source of the infection. This study demonstrates the influence of previous antibiotic administration on bacterial resistance rates although this fact is barely taken into account by the laboratory when constructing the cumulative susceptibility data. Real time clinical validation of the individual susceptibility reports, performed by a multidisciplinary team prior to the data entering, might be a suitable approach to get more reliable susceptibility rates to guide the rational selection of antimicrobial empirical therapy in patients with hospital-acquired infections who have been given antimicrobial treatment prior to specimen collection.

Whole-cell protein profiles are useful for distinguishing enterococcal species recovered from clinical specimens.

Whole-cell protein analysis was performed for differentiating 150 enterococcal isolates to the species level, which had previously been identified by extended phenotypic conventional tests. Whole-cell protein profile (WCPP) showed a high degree of similarity within species and comparison between species revealed important differences in band profiles. All Enterococcus faecalis and Enterococcus faecium isolates were properly located into their corresponding species, regardless of their clinical source and susceptibility pattern. Moreover, WCPP allowed relocation of some isolates that had erroneously been identified by the usual conventional scheme (i.e. two atypical arginine-negative E. faecalis isolates). WCPP proved to be a simple method to ascertain the various enterococcal species, especially those other than E. faecalis, and may be a suitable tool for high-complexity or reference clinical laboratories.

Review of pharmacokinetic, pharmacodynamic and clinical studies with a modern combination of amoxicillin/sulbactam.

Amoxicillin/sulbactam is a modern antimicrobial combination. This combination proved to be useful for the treatment of several infections caused by different microorganisms, mainly with the beta-lactamase-producing species. In this review we present the most relevant pharmacokinetic, pharmacodynamic and clinical information associated with its use.

Alternative indicators for monitoring the quality of a continuous intervention program on antibiotic prescribing during changing healthcare conditions.

We recently published on the impact of a four-phase hospital-wide intervention program designed to optimize the quality of antibiotic use, where a multidisciplinary team (MDT) could modify prescription at the last phase. Because health care quality was changing during the last 5 years (late 1999 to early 2004), we developed certain indicators to monitor the quality of our intervention over time. Different periods were defined as baseline (pre-intervention), initial intervention-active control, pre-crisis control, crisis control, post-crisis control and end of crisis control. Major indicators were rates of prescription modification by the MDT; prescription for an uncertain infection and a novel index formula (RIcarb) to estimate the rationale for carbapenem use. We assessed 2115 antimicrobial prescriptions. Modification of prescription rate was 30% at the beginning and decreased thereafter up to stable levels. Rate of prescriptions ordered for cases of both uncertain infection and unknown source of infection decreased significantly after intervention (i.e. from baseline to active control). In contrast, a doubling of culture-directed prescriptions was observed between these periods. RIcarb values lower and higher than 60% (modal, cut-off) were assumed as carbapenem overuse and underuse, respectively. Overuse was observed at the pre-intervention, while pronounced underuse was shown during the crisis (RIcarb, 45% and 87%, respectively). The present study demonstrates that certain indicators, other than the widely adopted impact outcomes, are a suitable tool for monitoring the quality of a continuous, long-term, active intervention on antimicrobial prescribing practice, especially when applied in a changing healthcare setting.

[Consensus for antimicrobial susceptibility testing for Enterobacteriaceae. Subcommittee on Antimicrobials, SADEBAC (Argentinian Society of Clinical Bacteriology), Argentinian Association of Microbiology]. / Consenso sobre las pruebas de sensibilidad a los antimicrobianos en Enterobacteriaceae.

Taking into account previous recommendations from the National Committee for Clinical Laboratory Standards (NCCLS), the Antimicrobial Committee, Sociedad Argentina de Bacteriología Clínica (SADEBAC), Asociación Argentina de Microbiología (AAM), and the experience from its members and some invited microbiologists, a consensus was obtained for antimicrobial susceptibility testing and interpretation in most frequent enterobacterial species isolated from clinical samples in our region. This document describes the natural antimicrobial resistance of some Enterobacteriaceae family members, including the resistance profiles due to their own chromosomal encoded beta-lactamases. A list of the antimicrobial agents that should be tested, their position on the agar plates, in order to detect the most frequent antimicrobial resistance mechanisms, and considerations on which antimicrobial agents should be reported regarding to the infection site and patient characteristics are included. Also, a description on appropriate phenotypic screening and confirmatory test for detection of prevalent extended spectrum beta-lactamases in our region are presented. Finally, a summary on frequent antimicrobial susceptibility profiles and their probably associated resistance mechanisms, and some infrequent antimicrobial resistance profiles that deserve confirmation are outlined.

Consenso sobre las pruebas de sensibilidad a los antimicrobianos en Enterobacteriaceae / Consensus for antimicrobial susceptibility testing for Enterobacteriaceae

En este documento se elaboraron una serie de recomendaciones para el ensayo, lectura, interpretación e informe de las pruebas de sensibilidad a los antimicrobianos para las enterobacterias aisladas con mayor frecuencia de especímenes clínicos. Se adoptaron como base las recomendaciones del National Committee for Clinical Laboratory Standards (NCCLS) de los EEUU, los de la subcomisión de Antimicrobianos, de la Sociedad Argentina de Bacteriología Clínica (SADEBAC), división de la Asociación Argentina de Microbiología (AAM) y de un grupo de expertos invitados. En él se indican las resistencias naturales de los diferentes miembros que integran la familia Enterobacteriaceae y se analiza la actividad de las diferentes beta-lactamasas cromosómicas, propias de cada especie, sobre las penicilinas, cefalosporinas y carbapenemes. Se recomiendan los antimicrobianos que se deberían ensayar, ubicados estratégicamente, para detectar los mecanismos de resistencia más frecuentes y cuales se deberían informar de acuerdo a la especie aislada, el sitio de infección y el origen de la cepa (intra o extrahospitalario). Se detallan los métodos de "screening" y de confirmación fenotipíca para detectar beta-lactamasas de espectro extendido (BLEE) que son más adecuados a nuestra realidad. Por último, se mencionan patrones infrecuentes de sensibilidad/resistencia que deberían verificarse y los perfiles de sensibilidad que pueden hallarse en las distintas enterobacterias en relación con los probables mecanismos de resistencia. Se debe resaltar que el contenido de este documento debe ser considerado como recomendaciones realizadas por expertos argentinos basadas en una revisión de la literatura y datos personales.

Taking into account previous recommendations from the National Committee for Clinical Laboratory Standards (NCCLS), the Antimicrobial Committee, Sociedad Argentina de Bacteriología Clínica (SADEBAC), Asociación Argentina de Microbiología (AAM), and the experience from its members and some invited microbiologists, a consensus was obtained for antimicrobial susceptibility testing and interpretation in most frequent enterobacterial species isolated from clinical samples in our region. This document describes the natural antimicrobial resistance of some Enterobacteriaceae family members, including the resistance profiles due to their own chromosomal encoded beta-lactamases. A list of the antimicrobial agents that should be tested, their position on the agar plates, in order to detect the most frequent antimicrobial resistance mechanisms, and considerations on which antimicrobial agents should be reported regarding to the infection site and patient characteristics are included. Also, a description on appropriate phenotypic screening and confirmatory test for detection of prevalent extended spectrum beta-lactamases in our region are presented. Finally, a summary on frequent antimicrobial susceptibility profiles and their probably associated resistance mechanisms, and some infrequent antimicrobial resistance profiles that deserve confirmation are outlined.

Consenso sobre las pruebas de sensibilidad a los antimicrobianos en Enterobacteriaceae. / [Consensus for antimicrobial susceptibility testing for Enterobacteriaceae. Subcommittee on Antimicrobials, SADEBAC (Argentinian Society of Clinical Bacteriology), Argentinian Association of Microbiology]

Taking into account previous recommendations from the National Committee for Clinical Laboratory Standards (NCCLS), the Antimicrobial Committee, Sociedad Argentina de Bacteriología Clínica (SADEBAC), Asociación Argentina de Microbiología (AAM), and the experience from its members and some invited microbiologists, a consensus was obtained for antimicrobial susceptibility testing and interpretation in most frequent enterobacterial species isolated from clinical samples in our region. This document describes the natural antimicrobial resistance of some Enterobacteriaceae family members, including the resistance profiles due to their own chromosomal encoded beta-lactamases. A list of the antimicrobial agents that should be tested, their position on the agar plates, in order to detect the most frequent antimicrobial resistance mechanisms, and considerations on which antimicrobial agents should be reported regarding to the infection site and patient characteristics are included. Also, a description on appropriate phenotypic screening and confirmatory test for detection of prevalent extended spectrum beta-lactamases in our region are presented. Finally, a summary on frequent antimicrobial susceptibility profiles and their probably associated resistance mechanisms, and some infrequent antimicrobial resistance profiles that deserve confirmation are outlined.

An ex-vivo pharmacodynamic study comparing bactericidal activity of amoxicillin/sulbactam, azithromycin, doxycycline and levofloxacin against Streptococcus pneumoniae.

We designed a 4-way crossover, ex-vivo pharmacodynamic study to compare the bactericidal rate of amoxicillin/sulbactam (AMX-SUL), azithromycin (AZM), doxycycline (DOX) and levofloxacin (LVX) against Streptococcus pneumoniae ATCC 49619. Six volunteers were randomized to receive alternatively a single tablet of the above drugs. Venous blood samples were obtained immediately before and at 2, 4 and 6 h after dose to perform time-kill studies and to determine antibiotic levels in serum. AMX-SUL was the only drug showing bactericidal activity with the sera obtained at every time after dose, as defined by a > or = 3-log10 cfu/ml decrease in the viable cell counts compared to the original inoculum after a 24-h incubation. AZM was only inhibitory at 2h after dose (i.e. a 1.3-log10 cfu/ml decrease in the viable cell counts) and proved bactericidal at 4 and 6 h post-dose. LVX proved bactericidal with the 2-h serum, was only inhibitory with the 4-h serum (e.g. a 1.5-log10 cfu/ml decrease) and was unable to avoid bacterial growth at 6 h post-dose. Bacterial growth was observed with DOX at every time after dose. This study may shed light on the understanding of breakthrough pneumococcal bacteremia during the course of oral therapy with AZM in patients with community-acquired nia (CAP), as well as the increasing treatment failures observed with LVX, and the selection of bacterial resistance during therapy reported with both drugs. It also provides the basis for a "warning signal" on the use of oral DOX and confirms the efficacy of AMX-SUL.

[Consensus on antimicrobial sensitivity tests in gram-positive cocci. Subcommittee on Antimicrobials, SADEBAC (Argentinian Society of Clinical Bacteriology), Argentinian Association of Microbiology]. / Consenso sobre las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos.

Antimicrobial susceptibility testing is mainly performed in Argentina by disk diffusion method, following National Committee for Clinical Laboratory Standards (NCCLS) recommendations. We worked out new recommendations for the reporting and interpretation of this test when dealing with gram-positive cocci, in accordance to local trends and epidemiology. General considerations for performing the diffusion assay, quality control, and an update on susceptibility testing for gram-positive cocci are reported in this first document. The present update should be considered as a group of recommendations summarized by Argentinean experts and as the result of a consensus meeting coordinated by the Subcomisión de Antimicrobianos of the Sociedad Argentina de Bacteriología Clínica (Asociación Argentina de Microbiología). Experts in antimicrobial agents were convened in order to prepare this final document. These recommendations take into account local needs, affordability and availability to be used in current practice, tending to contribute to the correct antimicrobial treatment election, according to the particular microorganism and the infection sites.

Consenso sobre las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos / Consensus for antimicrobial susceptibility testing for gram-positive cocci

El antibiograma por difusión en agar con discos se encuentra ampliamente difundido en nuestro medio y se basa primariamente en las recomendaciones del National Committee for Clinical Laboratory Standards (NCCLS). En este documento se elaboraron una serie de recomendaciones para el ensayo, lectura, interpretación e informe de las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos, adaptadas a la realidad argentina. En esta primera etapa se redactaron las consideraciones generales para la realización de la prueba por difusión, los controles de calidad internos para todos los microorganismos y una actualización sobre las pruebas de sensibilidad en cocos gram-positivos. Se debe resaltar que el contenido de este documento debe ser considerado como recomendaciones realizadas por expertos argentinos y que son el resultado de reuniones de consenso organizadas por la Subcomisión de Antimicrobianos de la Sociedad Argentina de Bacteriología Clínica, división de la Asociación Argentina de Microbiología. Se formó un equipo de trabajo integrado por expertos en antimicrobianos y a partir de una propuesta inicial, basada en una revisión de la literatura se fueron elaborando diversos documentos de trabajo que fueron mejorados después de ser debatidos por los miembros del grupo de trabajo hasta llegar al documento final. El criterio general fue elaborar recomendaciones acordes a las necesidades de nuestro país que puedan utilizarse en la práctica diaria con el objeto de colaborar en la adecuada elección del tratamiento antibiótico según la especie bacteriana aislada y la localización de la infección.

Consenso sobre las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos / Consensus for antimicrobial susceptibility testing for gram-positive cocci

El antibiograma por difusión en agar con discos se encuentra ampliamente difundido en nuestro medio y se basa primariamente en las recomendaciones del National Committee for Clinical Laboratory Standards (NCCLS). En este documento se elaboraron una serie de recomendaciones para el ensayo, lectura, interpretación e informe de las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos, adaptadas a la realidad argentina. En esta primera etapa se redactaron las consideraciones generales para la realización de la prueba por difusión, los controles de calidad internos para todos los microorganismos y una actualización sobre las pruebas de sensibilidad en cocos gram-positivos. Se debe resaltar que el contenido de este documento debe ser considerado como recomendaciones realizadas por expertos argentinos y que son el resultado de reuniones de consenso organizadas por la Subcomisión de Antimicrobianos de la Sociedad Argentina de Bacteriología Clínica, división de la Asociación Argentina de Microbiología. Se formó un equipo de trabajo integrado por expertos en antimicrobianos y a partir de una propuesta inicial, basada en una revisión de la literatura se fueron elaborando diversos documentos de trabajo que fueron mejorados después de ser debatidos por los miembros del grupo de trabajo hasta llegar al documento final. El criterio general fue elaborar recomendaciones acordes a las necesidades de nuestro país que puedan utilizarse en la práctica diaria con el objeto de colaborar en la adecuada elección del tratamiento antibiótico según la especie bacteriana aislada y la localización de la infección. (AU)

Consenso sobre las pruebas de sensibilidad a los antimicrobianos en cocos gram-positivos. / [Consensus on antimicrobial sensitivity tests in gram-positive cocci. Subcommittee on Antimicrobials, SADEBAC (Argentinian Society of Clinical Bacteriology), Argentinian Association of Microbiology]

Antimicrobial susceptibility testing is mainly performed in Argentina by disk diffusion method, following National Committee for Clinical Laboratory Standards (NCCLS) recommendations. We worked out new recommendations for the reporting and interpretation of this test when dealing with gram-positive cocci, in accordance to local trends and epidemiology. General considerations for performing the diffusion assay, quality control, and an update on susceptibility testing for gram-positive cocci are reported in this first document. The present update should be considered as a group of recommendations summarized by Argentinean experts and as the result of a consensus meeting coordinated by the Subcomisión de Antimicrobianos of the Sociedad Argentina de Bacteriología Clínica (Asociación Argentina de Microbiología). Experts in antimicrobial agents were convened in order to prepare this final document. These recommendations take into account local needs, affordability and availability to be used in current practice, tending to contribute to the correct antimicrobial treatment election, according to the particular microorganism and the infection sites.

Efficacy of amoxicillin-sulbactam, given twice-a-day, for the treatment of community-acquired pneumonia: a clinical trial based on a pharmacodynamic model.

The present multicenter study reports the results of a clinical trial, designed on the basis of a pharmacodynamic study published previously (Bantar et al., J. Chemother 2000; 12: 223-227) to assess the efficacy of amoxicillin/sulbactam (875 mg/125 mg), given orally twice-a-day for 7 days in the treatment of patients with community-acquired pneumonia (CAP). Eighty-four evaluable subjects older than 19 years with clinical symptoms and features suggestive of CAP, consulting from June 2000 to March 2002 and meeting the PORT risk class I through III, were enrolled in the study. Mean age (y +/- standard deviation) was 46.7 +/- 16.3 and 62% of the patients had some co-morbidity predisposing for CAP. Several individuals (77.4%) fell into a low-risk class (i.e. PORT I or II) and 22.6% of patients belonged to a moderate-risk class at the start of treatment. Six patients (6.45%) had pneumococcal bacteremia. Streptococcus pneumoniae was the organism most frequently isolated (61.9% of all the patients in whom an etiologic diagnosis was made), followed by Haemophilus influenzae. Clinical success was observed in 97.6% of the patients (confidence interval 95%, 94.3%-100%). Almost all the individuals with clinical success became afebrile within the first 3 days of therapy. Ten patients (11.8%) reported mild or moderate adverse events (especially diarrhea) possibly related to the antimicrobial therapy, but this did not lead to withdrawal from the trial. The results of this study suggest that amoxicillin/sulbactam (875 mg/125 mg) is an efficacious and well tolerated option for treating patients with CAP belonging to a low-moderate risk class and support the use of a short, oral (7-day) b.i.d. regimen.

Acute community-acquired pneumonia in adults: guidelines for initial antimicrobial therapy based on local evidence from a South American Working Group (ConsenSur).

Community-acquired pneumonia (CAP) is probably one of the infections affecting ambulatory patients for which the most diverse guidelines have been written worldwide. Most guidelines agree that antimicrobial therapy should be initially tailored according to either the severity of the infection or the presence of co-morbidity and epidemiology. Nevertheless, a great variability may be noted among different countries in the selection of first choice antimicrobial agents, even for cases considered as low-risk. This may be due to the many microbial causes of CAP and specialties involved, as well as different healthcare systems which affect the availability or cost of antibiotics. However, many countries or regions adopt some of the guidelines or design their own recommendations, regardless of the local data, probably because of the scarcity of such data. A committee composed of South American infectious diseases specialists and microbiologists, with strong interest and recognized experience in CAP, were convened to establish a working group (ConsenSur) for designing a local evidence-based practice guideline for the initial management of CAP. This supplement is intended to give a practice recommendation for the initial antimicrobial treatment of CAP upon the basis of local evidence, in the hope of procuring a suitable tool for use by the different health-care providers concerned with the management of this infection in South America or in other countries where the main considerations for CAP are comparable.