ABSTRACT
Staphylococcus aureus is the main agent of infections during peritoneal dialysis (PD). The presence of S. aureus in the nasal cavity has been extensively studied and suggested as a risk factor of dialysis-related infections, whereas coagulase-negative Staphylococcus (CNS) species are frequently considered part of the normal human microbiota. The aim of this study was to identify Staphylococcus in the nasal cavity, pericatheter skin and peritoneal effluent from PD patients, as well as to evaluate the antimicrobial activity evolution in vitro. Thirty-two chronic PD patients were observed during 12 months and had nasal and pericatheter skin samples collected for culture. When peritonitis was detected, samples were also collected from the peritoneal effluent for culture. The activity of several antimicrobial drugs (penicillin G, oxacillin, cephalothin, ofloxacin, netilmicin and vancomycin) against different Staphylococcus species was measured by using the agar drug diffusion assay (Kirby-Bauer method). Staphylococcus was separated into S. aureus, S. epidermidis and other CNS species in order to determine the in vitro resistance level. S. epidermidis resistance to oxacillin progressively increased during the study period (p < 0.05). Resistance to ofloxacin was inexpressive, whereas resistance to netilmicin and vancomycin was not detected. Of the oxacillin-resistant species (n = 74), 83 percent were S. epidermidis, 13 percent other CNS and 4 percent S. aureus (p < 0.05). Regarding multi-drug resistant strains (n = 45), 82 percent were S. epidermidis, 13 percent other CNS, and 5 percent S. aureus (p < 0.05). This study shows the relevance of resistance to oxacillin and CNS multi-drug resistance, particularly concerning S. epidermidis, in PD patients.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged, 80 and over , Coagulase , Peritoneal Dialysis/adverse effects , Renal Dialysis/adverse effects , Risk Factors , Sepsis , Staphylococcus aureusABSTRACT
The presence of Staphylococcus aureus in the nasal cavities and pericatheter skin of peritoneal dialysis patients put them at high risk of developing peritonitis. However, it is not clear whether the presence of coagulase-negative staphylococci (CNS) in the nasal passages and skin of patients is related to subsequent occurrence of peritoneal infection. The aim of the present study was to verify the relationship between endogenous sources of S. aureus and CNS and occurrence of peritonitis in patients undergoing peritoneal dialysis. Thirty-two patients on peritoneal hemodialysis were observed for 18 months. Staphylococcus species present in their nasal passage, pericatheter skin and peritoneal effluent were identified and compared based on drug susceptibility tests and dendrograms, which were drawn to better visualize the similarity among strains from extraperitoneal sites as well as their involvement in the causes of infection. Out of 288 Staphylococcus strains isolated, 155 (53.8 percent) were detected in the nasal cavity, 122 (42.4 percent) on the skin, and 11 (3.8 percent) in the peritoneal effluent of patients who developed peritonitis during the study. The most frequent Staphylococcus species were CNS (78.1 percent), compared with S. aureus (21.9 percent). Among CNS, S. epidermidis was predominant (64.4 percent), followed by S. warneri (15.1 percent), S. haemolyticus (10.7 percent), and other species (9.8 percent). Seven (64 percent) out of 11 cases of peritonitis analyzed presented similar strains. The same strain was isolated from different sites in two (66 percent) out of three S. aureus infection cases. In the six cases of S. epidermidis peritonitis, the species that caused infection was also found in the normal flora. From these, two cases (33 percent) presented highly similar strains and in three cases (50 percent), it was difficult to group strains as to similarity. Patients colonized with multidrug-resistant S. epidermidis...
Subject(s)
Humans , Male , Female , Adult , Coagulase , Peritoneal Dialysis/adverse effects , Peritonitis , Staphylococcal Infections , Staphylococcus aureus , Staphylococcus epidermidisABSTRACT
Objetivo. Avaliar a atividade in vitro da cefalosporina de quarta geraçao, cefpiroma em comparaçao com ceftazidima, ceftriaxona, cefotaxima e imipenem em um estudo multicêntrico envolvendo nove hospitais de seis cidades em quatro estados. Material e Métodos. Foram estudadas 804 amostras clínicas isoladas em pacientes internados em unidades de terapia intensiva ou unidades de oncohematologia. As amostras foram coletadas no período de junho a novembro de 1995, isto é, antes da cefpiroma estar disponível comercialmente no Brasil, e testadas através do método de microdiluiçao em placas conforme descrito pelo National Committee for Clinical Laboratory Standards (NCCLS). Todas as amostras resistentes à cefpiroma foram retestadas utilizando-se o E-test. Resultados. Contra as amostras de enterobactérias (n=344), a cefpiroma apresentou atividade de 2 a 32 vezes superior àquela apresentada pelas cefalosporinas de terceira geraçao (CTGs) e semelhnate àquela apresentada pelo imipenem. As porcentagens de enterobactérias sensíveis foram: 88 por cento para a cefpiroma, 69 por cento para as CTGs e 96 por cento para o imipenem. O espectro de açao da cefpiroma foi maior ou igual ao do imipenem contras as espécies Citrobacter freundii, E. aerogenes, Morganella morganii e Serratia marcescens. Contra Acinetobacter sp. (n=77), a cefpiroma foi ligeiramente mais ativa que a ceftazidima, porém as porcentagens de resistência foram muito altas para esses compostos (84 por cento e 88 por cento respectivamente). As atividades da cefpiroma, ceftazidima e imipenem foram semelhantes contra Pseudomonas aeruginosa (n=128), com MIC50/porcentagem de sensibilidade de 8/59 por cento, 8/62 por cento e 4/62 por cento respectivamente. Contra bactérias aeróbias gram-positivas, a cefpiroma foi de 4 a 16 vezes mais ativa que as CTGs. Contra S. epidermidis e outras espécies de estafilococos coagulase-negativos a cefpiroma foi ligeiramente superior ao imipenem, porém, contra as outras espécies de bactérias gram-positivas avaliadas, o imipenem apresentou atividade um pouco superior. Conclusao: Os resultados desse estudo sugerem que, no Brasil, a cefpiroma apresenta espectro de açao superior ao das CTGs contra bactérias gram-negativas (Enterobacteriaceae e nao fermentadares) e gram-positivas e semelhante ao do imipenem contra algumas espécies de enterobactérias e contra P. aeruginosa.
Subject(s)
Cephalosporin Resistance , Cephalosporins/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Lactams/pharmacology , Bacterial Infections/microbiology , Intensive Care Units , Microbial Sensitivity TestsABSTRACT
Estudamos 20 pacientes do sexo feminino com episodio agudo de infeccao urinaria, caracterizada clinica e laboratorialmente antes de iniciada a terapeutica com a associacao do complexo alfquimotripsina-tripsina, lisozima e ampicilina. Houve 14 pacientes curados (70%) e seis com infeccao recorrente (30%), todas estas referindo antecedentes de infeccao previa do trato urinario. Efeitos colaterais registrados em seis casos nao impediram a execucao do esquema de tratamento planejado