Antibiotic Susceptibility Testing and Standardization

In vitro tests of antibacterial activity are as old as penicillin, and possibly even older. They have undergone divergent evolution in different parts of the world. It has to be known that methods established in USA by National Committee for Clinical Laboratory (NCCLS) at present dominate in many countries. The aim of susceptibility testing is that it gives the right answer rather than it is performed in rigorously standardized manner. The result must be useful in predicting response of the patient treated with the antibacterial drug. However there are so many confounding factors in determining the relationship between the in vitro susceptibility and clinical response: the drug, the infecting organism and the patient. Contemporary clinical microbiology laboratories have many methods to choose for their routine antimicrobial susceptibility testing: disk diffusion test, agar dilution test, broth dilution tests (macro and micro), E test. Rapid commercial microdilution and rapid automated instruments methods are also available. There are many variables affecting the susceptibility test results : inoculum, incubation conditions, depth of the agar etc.. Each laboratory must consider all of these factors in order to have reproducible results from antibiotic susceptibility tests. In this article, the factors affecting the results of antibiotic susceptibility testing are discussed and a general approach to definition of breakpoins is also considered

Pneumococcal Serogroups Causing the Most of the Invasive Diseases in Kayseri

The aim of this study was to compare the serogroups causing invasive pneumococcal disease (IPD) with those represented in both currently available polysaccharide vaccine and conjugate vaccine formulations. We evaluated 69 Streptococcus pneumoniae strains isolated from 31 children and 38 adults in Erciyes University Hospital in the period from January 1998 to January 2000. The strains were isolated from cerebrospinal fluid (n= 31), blood (n= 28), and pleural fluid (n= 10). Serotyping was performed using Pneumotest (Statens Seruminstitute, Denmark). Serogroups of 6 (8%) strains could not be defined. The remaining 63 strains belonged to serogroup 19, 1, 6, 23, 3, 15, 14, and 7 by order of decreasing frequency. Serogroups in the 23- valent polysaccharide vaccine, 7-valent, 9-valent, and 11-valent conjugate vaccine formulations covered 91%, 68%, 81%, and 87% of IPD strains in our region respectively. Although some of the serogroups not found in these vaccine formulations are important causes of disease, each formulation can prevent a substantial number of IPD cases in this region

Gastroenteritli olgularda Enterohemorrahagic E. coli 0157:H7 serotipi araştırılması.

Frequencies of occurrence of low-level image features is the representation of choice in the design of state-of-the-art visual object recognition systems. A crucial step in this process is the construction of a codebook of visual features, which is usually done by cluster analysis of a large number of low-level image features detected as interest points. However, clustering is a process that retains regions of high density in a distribution and it follows that the resulting codebook need not have discriminant properties. Here we extend our recent work on constructing a one-pass discriminant codebook design procedure inspired by the resource allocating network model from the artificial neural networks literature. Unlike clustering, this approach retains data spread out more widely in the input space, thereby including rare low-level features in the codebook. It simultaneously achieves increased discrimination and a drastic reduction in the computational needs. We illustrate some properties of our method and compare it to a closely related approach

Brucella peritonitis in a patient on continuous ambulatory peritoneal dialysis with acute brucellosis

Peritonitis is an uncommon complication of brucellosis. Brucella peritonitis in chronic ambulatory peritoneal dialysis (CAPD) patients has not been reported before. A male patient is presented with peritonitis caused by Brucella melitensis who was on CAPD. The source of infection was thought to be unpasteurized, unsalted cheese eaten a month before the onset of symptoms. At the beginning, antibiotic therapy with doxycyline and rifampicin led to a rapid clinical improvement, with disappearance of the organism in the peritoneal fluid. However, peritonitis relapsed after discontinuation of antimicrobial therapy. Successful management required a combination of medical therapy and removal of the Tenckhoff catheter. Copyrlight (C) 2002 S. Karger AG, Basel