Appropriate screening of early asymptomatic cases can reduce the disease burden and mortality rate of sporadic colorectal cancer (CRC) significantly. Currently, fecal occult blood testing (FOBT) is able to detect up to 80% of asymptomatic cases in the population aged 50+. Therefore, there is still a demand for new screening tests that would complement FOBT, mainly by detecting at least a part of the FOBT-negative CRC and adenoma cases, or possibly by identifying person at increased risk of sporadic CRC in order to offer them tailored follow-up. Among the potential markers studied, our knowledge has advanced at most in toxigenic gram-negative bacteria. In this review, we assess their potential critically and recommend those best suited for prospective evaluation of their true ability to increase the sensitivity of FOBT when combined during general population screening. In our opinion, colibactin and Bacteroides fragilis toxin are the best candidates, possibly complemented by the cytotoxic necrotizing factor (CNF).
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- abstrakt z konference MeSH
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- abstrakt z konference MeSH
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- abstrakt z konference MeSH
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- abstrakt z konference MeSH
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- abstrakt z konference MeSH
The role of gut microbiota in the development of sporadic colorectal cancer (CRC) is supported by a number of studies, however, the conclusiveness of published metagenomic studies is questioned by technical pitfalls and limited by small cohort sizes. In this review, we evaluate the current knowledge critically and outline practical solutions. We also list candidate CRC risk markers that are - in our opinion - well supported by available data and thus deserve clinical validation. Last but not least, we summarise available knowledge useful for improving care for patients immediately.
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- abstrakt z konference MeSH
Streptococcus milleri group (SMG) is a group of three streptococcal species (S. anginosus, intermedius and constellatus) that act as opportunist pathogens, among others in cystic fibrosis. Due to their fastidious character, they are both difficult to cultivate and to differentiate from less pathogenic streptococcal species, therefore being most probably underdiagnosed. Semi-selective McKay agar and NAS agar were developed to facilitate SMG recovery from clinical samples; however, direct comparison of recovery rates has not been published yet. We tested the performance of both media on 123 patient samples and demonstrated general superiority of NAS agar for SMG recovery during primary cultivation convincingly. This observation was also confirmed by quantitative drop tests during subculture. Despite the undisputed overall superiority of NAS agar over McKay agar, a smaller fraction of strains grew better on McKay agar. Inter-strain differences were the most probable explanation. Therefore, when economic conditions are not limiting and maximum recovery rate is desirable, both plates are advised to be used in parallel for primary cultivation of clinical samples.
BACKGROUND AND AIMS: Haemophilus influenzae new strain acquisition has been demonstrated to increase the relative risk of acute exacerbation fourfold in contrast to colonisation or chronic infection by the same strain in chronic obstructive pulmonary disease (COPD). Unfortunately, molecular typing techniques are not suitable for routine use due to cost, labour-intensity and need for special expertise. We tested two techniques potentially useful for routine typing, namely the newly available MALDI-TOF MS and the modified McRAPD compared to MLST as the gold standard. METHODS: In 10 patients (10.8%) suffering from COPD or cystic fibrosis, H. influenzae isolates were recovered repeatedly at different timepoints from the same patient during the study period. This allowed for thirteen pairwise comparisons of typing results in isolates recovered consecutively from the same patient to test the ability of the techniques to uncover new strain acquisition. RESULTS: MLST detected 9 cases of new strain acquisition among the 13 pairwise comparisons. However, MALDI-TOF MS reported all 13 pairs as different and thus new. In contrast, McRAPD was able to differentiate all the new strain acquisitions from pre-existing ones, both by visual inspection of melting profiles and by Relative Significant Difference values. CONCLUSIONS: Unlike MALDI-TOF MS, McRAPD appears to be a suitable candidate for routine discrimination of new strain acquisitions because of its accuracy and, rapid, easy and economic performance.
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- chronická obstrukční plicní nemoc diagnóza MeSH
- cystická fibróza diagnóza MeSH
- diferenciální diagnóza MeSH
- Haemophilus influenzae izolace a purifikace MeSH
- hemofilové infekce diagnóza MeSH
- lidé MeSH
- senzitivita a specificita MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice metody normy MeSH
- techniky typizace bakterií metody normy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
