15 research outputs found
Infecção cutânea causada por Corynebacterium pseudodiphtheriticum: relato microbiológico
Reportamos o isolamento de Corynebacterium pseudodiphtheriticum de um caso de infecção cutânea. O paciente apresentou-se ao laboratĂłrio clĂnico com uma Ăşlcera na perna esquerda. A coloração de Gram do material revelou a presença de bacilos Gram-positivos e ausĂŞncia de outras espĂ©cies bacterianas. O organismo foi isolado em cultura pura no ágar sangue de carneiro e foi identificado como C. pseudodiphtheriticum atravĂ©s de um sistema de identificação comercial (API-Coryne, BioMĂ©rieux, França). A infecção foi tratada com sucesso atravĂ©s do uso de ciprofloxacina. Este caso reforça a importância do laboratĂłrio de microbiologia clĂnica na identificação de organismos Gram-positivos isolados de cultura pura de amostras de Ăşlceras cutâneas.We report here a rare case of cutaneous infection due to Corynebacterium pseudodiphtheriticum. The patient presented to the clinical laboratory with a skin ulcer on his left leg. Gram-stained preparation of the purulent secretion revealed the presence of numerous rod-shaped Gram-positive organisms in the absence of any other species. The organism was grown in pure culture on sheep blood agar and was further identified as C. pseudodiphtheriticum using a commercial identification system (API-Coryne, BioMĂ©rieux, France). The infection was successfully treated with ciprofloxacin. This case emphasizes the importance of the clinical microbiology laboratory in correctly identifying Gram-positive organisms obtained in pure culture from skin ulcers
Evaluation of Aztreonam and Ceftazidime/Avibactam Synergism against <i>Klebsiella pneumoniae</i> by MALDI-TOF MS
Introduction: Resistance to carbapenems due to the co-production of NDM and ESBL or NDM and KPC is increasing. Therefore, combined therapy with aztreonam (ATM) plus ceftazidime/avibactam (CZA) has been recommended. Then, it is necessary to develop and evaluate fast and simple methods to determine synergism in vitro in microbiology laboratories. Objective: To develop a method to determine the synergism of ATM and CZA by MALDI-TOF MS (SynMALDI). Method: Klebsiella pneumoniae (n = 22) isolates with blaNDM and/or blaKPC genes were tested. The time–kill curve assay was performed for four isolates (three positives for blaNDM and blaKPC and one positive for blaNDM only). For SynMALDI, each isolate was incubated for 3 h in 4 tubes containing brain–heart infusion broth with the following: (1) no antibiotic; (2) ATM at 64 mg/L; (3) CZA at 10/4 mg/L; and (4) ATM at 64 mg/L plus CZA at 10/4 mg/L. After incubation, the bacterial protein extract was analyzed by MALDI-TOF MS, and the relative growth (RG) was determined for each isolate, considering intensities of the peaks of the bacterium incubated with antibiotic (tubes 2, 3, and 4) to the same bacterium incubated without antibiotic (tube 1), as follows: RG = IntensityWith antibiotic/IntensityWithout antibiotic. The combination was determined as synergistic when there was an RG decrease of 0.3 in the antibiotic combination in relation to the RG of the most active antibiotic alone. Results: The combination of ATM plus CZA proved to be synergic by time–kill curve assay. All isolates tested with the SynMALDI method also presented synergism. Conclusions: Detection of synergism for ATM plus CZA combination can be determined by MALDI-TOF MS, providing fast results in order to improve patient treatment
Diphyllobothrium latum: relato de caso no Brasil
Difilobotriose Ă© causada em humanos pela infecção com vermes adultos do gĂŞnero Diphyllobothrium adquiridos pelo consumo de peixe cru ou mal cozido. Diphyllobothrium latum foi confirmado pelo exame dos proglotes grávidos e tĂpicos ovos operculados nas fezes. O paciente havia comido crustáceos e peixes. É o relato do primeiro brasileiro infectado
Utility of the ceftazidime-imipenem antagonism test (CIAT) to detect and confirm the presence of inducible AmpC beta-lactamases among enterobacteriaceae
Detection of AmpC beta-lactamase production by enterobacteria has been problematic. Contrary to ESBLs, no specific guidelines are available for detection and confirmation of AmpC production by clinical relevant microorganisms. Moreover, some bacterial species may produce inducible AmpC beta-lactamases that can be easily overlooked by routine susceptibility tests. We reported here a new test based on the strong inducible effect of imipenem on AmpC genes and the consequent antagonism with ceftazidime. This test is very simple and proved to be helpful in detecting AmpC-inducible enzymes among several species of clinical isolates