RESUMO
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.
Assuntos
Antibacterianos/farmacologia , Mastite Bovina/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Argentina , Bovinos , Indústria de Laticínios , Testes de Sensibilidade Microbiana , Staphylococcus aureus/isolamento & purificaçãoRESUMO
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 (Assuntos
Antibacterianos/farmacologia
, Bactérias Aeróbias/efeitos dos fármacos
, Farmacorresistência Bacteriana
, Minociclina/análogos & derivados
, Adulto
, Argentina
, Humanos
, Técnicas In Vitro
, Testes de Sensibilidade Microbiana
, Minociclina/farmacologia
, Tigeciclina
RESUMO
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.
Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana , Humanos , Fatores de RiscoRESUMO
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.
Assuntos
Proteínas de Bactérias/análise , Técnicas de Tipagem Bacteriana/métodos , Enterococcus/classificação , Infecções por Bactérias Gram-Positivas/microbiologia , Eletroforese em Gel de Poliacrilamida , Enterococcus/química , Enterococcus/isolamento & purificação , Enterococcus faecalis/química , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/química , Enterococcus faecium/isolamento & purificação , Humanos , Especificidade da EspécieRESUMO
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.
Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde , Indicadores de Qualidade em Assistência à Saúde , Carbapenêmicos/uso terapêutico , Atenção à Saúde/normas , Atenção à Saúde/tendências , Prescrições de Medicamentos/estatística & dados numéricos , Farmacorresistência Bacteriana , Hospitais com 100 a 299 Leitos , Humanos , Relações Interprofissionais , Estudos LongitudinaisRESUMO
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.
Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Antibacterianos/uso terapêutico , Proteínas de Bactérias/análise , Resistência a Medicamentos , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana/economia , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Fenótipo , Controle de Qualidade , beta-Lactamases/análiseRESUMO
Fifteen unique isolates of carbapenem-resistant Pseudomonas aeruginosa were selected for time-kill studies to assess the bactericidal activity of cefepime (CFP) and ceftazidime (CZD) (at 4 and 16 microg/mL), alone and associated with amikacin (AMK) (4 microg/mL). CFP proved more active than CZD (p < 0.05, Student's t test). Bactericidal activity after 24-h incubation was only achieved by the combination of CFP (16 microg/mL) plus AMK. The higher in vitro activity of cefepime over that of ceftazidime against imipenem-resistant P. aeruginosa strains highlights the differences of these drugs beyond Enterobacterspp. and Staphylococcus aureus.
Assuntos
Amicacina/farmacologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Ceftazidima/farmacologia , Cefalosporinas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Cefepima , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/isolamento & purificaçãoRESUMO
We compared the performance of several phenotypic tests to detect methicillin-resistant Staphylococcus aureus, with special focus on borderline strains. The reliability of the agar screen oxacillin and BBL Crystal tests was asserted for all methicillin-susceptible (n = 25), -resistant (n = 29) and borderline beta-lactamase-hyperproducer (n = 10) strains. Whereas these tests failed to detect 4 of 5 rare borderline strains containing few cells with high-level methicillin resistance (i.e., a frequency of 10(-7)-10(-8)), a "two-temperature" disk diffusion method, performed simultaneously at 35 and 42 degrees C, detected all of such strains.
Assuntos
Resistência a Meticilina/genética , Staphylococcus aureus/efeitos dos fármacos , Ampicilina/farmacologia , Contagem de Colônia Microbiana , Humanos , Oxacilina/farmacologia , Penicilinas/farmacologia , Fenótipo , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Cloreto de Sódio/farmacologia , Staphylococcus aureus/genéticaRESUMO
The in vitro activity of gatifloxacin and levofloxacin, ciprofloxacin, penicillin, ampicillin, ampicillin-sulbactam, ceftriaxone and clarithromycin was evaluated against 173 S. pneumoniae strains (128, penicillin-susceptible strains; 32, intermediate penicillin- resistant strains and 13, penicillin-resistant strains), 163 H. influenzae strains (128, beta-lactamase non-producer; 35, beta-lactamase producers), 111 M. catarrhalis (9, beta-lactamase non-producer; 102, beta-lactamase producers), 95 Streptococcus pyogenes and 116 S. aureus strains (96, methicillin-susceptible; 20, methicillin-resistant) recovered from outpatients with respiratory tract infection. Based upon the MICs at which 50% and 90% of the isolates were inhibited we concluded that gatifloxacin proved to be the most active antibiotic against respiratory pathogens, including all the penicillin-resistant pneumococci and H. influenzae or M. catarrhalis producing beta-lactamase. Furthermore, their MICs against S. pneumoniae and methicillin-resistant S. aureus were lower than those of levofloxacin and ciprofloxacin.Therefore, this new fluoroquinolone displayed in vitro features that make it suitable for treating community-acquired respiratory tract infections.
Assuntos
Anti-Infecciosos/farmacologia , Fluoroquinolonas , Haemophilus influenzae/efeitos dos fármacos , Moraxella catarrhalis/efeitos dos fármacos , Infecções Respiratórias/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Resistência Microbiana a Medicamentos , Gatifloxacina , Haemophilus influenzae/crescimento & desenvolvimento , Haemophilus influenzae/isolamento & purificação , Humanos , Macrolídeos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/crescimento & desenvolvimento , Moraxella catarrhalis/isolamento & purificação , Pacientes Ambulatoriais , Penicilinas/farmacologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/isolamento & purificação , Streptococcus pneumoniae/crescimento & desenvolvimento , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
INTRODUCTION: A national surveillance program (SIR) was introduced in 1996 in Argentina by the Antimicrobial Committee of the Argentinean Society for Microbiology to assess bacterial resistance. The present study reports the rates of nosocomial bacterial resistance found by this program. METHODS: A 2-month point-prevalence study was conducted twice yearly (i.e., April-May and October-November) from 1996 to 1998, by 27 Argentinean centers. Susceptibility testing was carried out by the disk diffusion method following the National Committee for Clinical Laboratory Standards guidelines. RESULTS: In all, 6343 isolates recovered from 5603 inpatients (> or =48-hr hospitalization) were included. Methicillin resistance was 58% and 56% in Staphylococcus aureus and coagulase-negative staphylococci (CNS), respectively. Although no vancomycin resistance was found in staphylococci, 2% and 8% of the S. aureus and CNS strains, respectively, proved resistant to teicoplanin. No ampicillin resistance was displayed by Enterococcus faecalis. High-level gentamicin and streptomycin resistance in enterococci were 33% and 37%, respectively. Acquired glycopeptide resistance in enterococci emerged in 1997 (2%). Imipenem resistance in Acinetobacter spp and Pseudomonas aeruginosa was 9% and 21%, respectively. Among Enterobacteriaceae, 1% and 5% of the Klebsiella pneumoniae and Enterobacter cloacae isolates, respectively, proved resistant to imipenem. Ceftazidime and cefepime resistance was found in 63% and 33% of the E. cloacae strains. Resistance to extended-spectrum cephalosporins was shown by 48%, 26%, and 8% of the K. pneumoniae, Proteus mirabilis, and Escherichia coli isolates, respectively. CONCLUSIONS: The alarming rates of resistance found in this study provide compelling evidence of the need for more rational use of antimicrobial agents in Argentina.
Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Resistência Microbiana a Medicamentos , Argentina/epidemiologia , Bacteriemia/microbiologia , Bactérias/isolamento & purificação , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Vigilância da PopulaçãoRESUMO
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.
Assuntos
Amoxicilina/farmacologia , Azitromicina/farmacologia , Doxiciclina/farmacologia , Levofloxacino , Ofloxacino/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Sulbactam/farmacologia , Adulto , Amoxicilina/sangue , Análise de Variância , Azitromicina/sangue , Atividade Bactericida do Sangue , Contagem de Colônia Microbiana , Estudos Cross-Over , Doxiciclina/sangue , Farmacorresistência Bacteriana , Quimioterapia Combinada/uso terapêutico , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Ofloxacino/sangue , Probabilidade , Sensibilidade e Especificidade , Teste Bactericida do Soro , Método Simples-Cego , Estatísticas não Paramétricas , Streptococcus pneumoniae/isolamento & purificação , Sulbactam/sangueRESUMO
In order to establish a rationale for treating community-acquired lower respiratory tract infections, we assess here the pharmacodynamics of amoxicillin/sulbactam, 500mg/500mg, a formulation marketed in Argentina since 1988 and currently available in 17 countries, against the major pathogens, in comparison with that of a novel formulation (875mg/125mg, see J Chemother 2000; 12: 223-227). In time-kill studies, both bactericidal and inhibitory activity were seen in the 1.5- and 6-h sera, obtained from 12 volunteers after a single oral dose, against both a penicillin-susceptible and an -intermediate Streptococcus pneumoniae strain, as well as against Moraxella catarrhalis and a beta-lactamase-negative Haemophilus influenzae strain. Only the 1.5-h sera proved bactericidal against a penicillin-resistant S. pneumoniae strain (MIC, 2 microg/ml) and a beta-lactamse-positive H. influenzae isolate. This study suggests that amoxicillin/sulbactam (500mg/500mg) is still a suitable option for treating community-acquired lower respiratory tract infections, allowing a b.i.d. dosing schedule. Caution should be taken with pneumonia caused by beta-lactamase-positive H. influenzae or penicillin-resistant (MIC > or =2 microg/ml) S. pneumoniae isolates. Either shorter dosing intervals (t.i.d.) or a higher amoxicillin content in the formulation (i.e. 875 mg) may be required in these situations.
Assuntos
Infecções Comunitárias Adquiridas/tratamento farmacológico , Quimioterapia Combinada/farmacologia , Haemophilus influenzae/efeitos dos fármacos , Moraxella catarrhalis/efeitos dos fármacos , Pneumonia Bacteriana/tratamento farmacológico , Streptococcus pneumoniae/efeitos dos fármacos , Administração Oral , Adulto , Amoxicilina/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Feminino , Haemophilus influenzae/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/isolamento & purificação , Resistência às Penicilinas , Pneumonia Bacteriana/microbiologia , Teste Bactericida do Soro , Streptococcus pneumoniae/isolamento & purificação , Sulbactam/farmacologiaRESUMO
We evaluated, by time-kill studies, the pharmacodynamics of amoxicillin/sulbactam (AMX/SUL, 875 mg/125 mg), a novel oral combination, against the major respiratory pathogens in 12 volunteers receiving a single dose. The sera corresponding to 50% of a 12-h dosing interval displayed either bactericidal or inhibitory activity against both a penicillin-susceptible and a penicillin-intermediate Streptococcus pneumoniae strain (penicillin MIC of 0.03 and 0.25 microg/ml, respectively), as well as against a beta-lactamase-positive Moraxella catarrhalis and a beta-lactamase-negative Haemophilus influenzae strain. Both the peak samples and those corresponding to 4 h after dose (i.e. 33% of a 12-h dosing interval) proved active against both a penicillin-resistant S. pneumoniae (MIC, 2 microg/ml) and a beta-lactamase-positive H. influenzae strain. The AMX-SUL formulation evaluated in this study showed pharmacodynamic features that support clinical trials to assess its efficacy in the treatment of lower respiratory tract infections with a 12-h dosing interval regimen.
Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Quimioterapia Combinada/administração & dosagem , Penicilinas/administração & dosagem , Infecções Respiratórias/tratamento farmacológico , Sulbactam/administração & dosagem , Administração Oral , Adulto , Amoxicilina/sangue , Amoxicilina/farmacocinética , Antibacterianos/sangue , Antibacterianos/farmacocinética , Infecções Comunitárias Adquiridas/sangue , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Esquema de Medicação , Combinação de Medicamentos , Quimioterapia Combinada/sangue , Quimioterapia Combinada/farmacocinética , Feminino , Infecções por Haemophilus/sangue , Infecções por Haemophilus/tratamento farmacológico , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Humanos , Masculino , Modelos Biológicos , Moraxella catarrhalis/efeitos dos fármacos , Moraxella catarrhalis/isolamento & purificação , Infecções por Neisseriaceae/sangue , Infecções por Neisseriaceae/tratamento farmacológico , Infecções por Neisseriaceae/microbiologia , Penicilinas/sangue , Penicilinas/farmacologia , Infecções Pneumocócicas/sangue , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/microbiologia , Infecções Respiratórias/sangue , Infecções Respiratórias/microbiologia , Teste Bactericida do Soro , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Sulbactam/sangue , Sulbactam/farmacocinéticaRESUMO
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.
Assuntos
Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Doença Aguda , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/mortalidade , Farmacorresistência Bacteriana , Medicina Baseada em Evidências , Humanos , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/mortalidade , América do SulRESUMO
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.
Assuntos
Amoxicilina/administração & dosagem , Quimioterapia Combinada/administração & dosagem , Pneumonia Bacteriana/tratamento farmacológico , Sulbactam/administração & dosagem , Administração Oral , Adulto , Idoso , Infecções Comunitárias Adquiridas/tratamento farmacológico , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
A 26-year-old male AIDS patient with diarrhea of two-months evolution is reported here. The most relevant intestinal pathogens, including Cryptosporidium parvum, were ruled out by routine microbiological tests. Stool samples stained with an "oblong" Ziehl-Neelsen method (fucsin, 7 min instead of 3 min) allowed visualization of organisms resembling microsporidia. Both modified trichrome and calcofluor stains showed organisms compatible with Enterocytozoon bieneusi. Significant titer of antibodies (> or = 1/800) against 4 different microsporidial species were obtained from the serum of the patient by an ELISA test. Clinical improvement was observed after treatment with albendazole, 400 mg twice daily for 4 weeks, even though microsporidial spores were still detected in stool specimens. To our knowledge, this is the first microsporidial infection reported in Argentina.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Diarreia/etiologia , Microsporidiose/complicações , Infecções Oportunistas Relacionadas com a AIDS/patologia , Adulto , Animais , Anticorpos Antibacterianos/análise , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Humanos , Masculino , Microsporida/imunologiaRESUMO
Lactobacillus endocarditis is a rare infection. In fact, only 42 cases have been described in the literature from 1938 up to date. In only 17 previously reported cases have patients been cured with medical therapy alone. Although infections produced by Lactobacillus spp, have been described in our country, none of them included endocarditis. We report herein a case of endocarditis due to a vancomycin-resistant strain of Lactobacillus casei sub. rhamnosus in a 29-year-old man with prolapse of the mitral valve. He required surgical replacement of his valve because of the poor response to antimicrobial therapy with penicillin and gentamicin. The patient displayed a successful clinical outcome, with no evidence of recurrence along the subsequent 2 years. We point out the need to accurately identify Lactobacillus spp. in isolates from blood cultures of patients with endocarditis, since these bacteria may often be mistaken for other species more frequently associated to this infection, which usually respond to conventional antimicrobial therapy. Furthermore, we suggest that early surgical replacement should be considered when lactobacillus endocarditis is diagnosed.
Assuntos
Endocardite/cirurgia , Lacticaseibacillus casei/isolamento & purificação , Valva Mitral/transplante , Adulto , Antibacterianos/uso terapêutico , Doenças Transmissíveis , Resistência Microbiana a Medicamentos , Endocardite/tratamento farmacológico , Endocardite/etiologia , Humanos , MasculinoRESUMO
Detection of pyrrolidonyl-aryl-amidase activity (PYR) is an important tool to identify gram-positive cocci, such as staphylococci, enterococci, streptococci, and other related genera. However, only few studies evaluating its usefulness with gram-negative rods have been published. Thus, a prospective study including 542 and 215 unique clinical isolates of Enterobacteriaceae and non-fermentative gram-negative rods, respectively, was undertaken. Strains were identified by conventional methods. PYR test was performed using a commercial kit, according to the manufacturer recommendations. Positive results were uniformly obtained for the PYR test with the following species: Citrobacter spp, Klebsiella spp, Enterobacter aerogenes, Enterobacter agglomerans group, Serratia marcescens and S. odorifera. On the other hand, negative results were uniformly displayed by E. coli (including inactive E. coli), Protease group, Salmonellia spp, Shigella spp, Acinetobacter spp, Burkholderia (Pseudomonas) cepacia and Flavobacterium spp. Variable results were shown in Pseudomonas aeruginosa, Stenotrophomonas (xanthomonas) malthophilia, Kluyvera cryocrescens, and Enterobacter cloacae. PYR test proved to be a reliable and simple tool to rapidly distinguish certain species belonging to Enterobacteriaceae (ie. Citrobacter freundii from Salmonella spp, and inactive E. coli from K. ozaenae). Further studies, including a wide diversity of species, are required to assess usefulness of the PYR test for the identification of non-fermentative gram-negative rods.
Assuntos
Aminopeptidases/análise , Proteínas de Bactérias/análise , Técnicas de Tipagem Bacteriana , Enterobacteriaceae/classificação , Bactérias Gram-Negativas/classificação , Enterobacteriaceae/enzimologia , Estudos de Avaliação como Assunto , Bactérias Gram-Negativas/enzimologia , Ácido Pirrolidonocarboxílico/análogos & derivados , Especificidade da EspécieRESUMO
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.