scholarly journals Detection and Differentiation of Chlamydiae by Fluorescence In Situ Hybridization

2002 ◽  
Vol 68 (8) ◽  
pp. 4081-4089 ◽  
Author(s):  
Sven Poppert ◽  
Andreas Essig ◽  
Reinhard Marre ◽  
Michael Wagner ◽  
Matthias Horn

ABSTRACT Chlamydiae are important pathogens of humans and animals but diagnosis of chlamydial infections is still hampered by inadequate detection methods. Fluorescence in situ hybridization (FISH) using rRNA-targeted oligonucleotide probes is widely used for the investigation of uncultured bacteria in complex microbial communities and has recently also been shown to be a valuable tool for the rapid detection of various bacterial pathogens in clinical specimens. Here we report on the development and evaluation of a hierarchic probe set for the specific detection and differentiation of chlamydiae, particularly C. pneumoniae, C. trachomatis, C. psittaci, and the recently described chlamydia-like bacteria comprising the novel genera Neochlamydia and Parachlamydia. The specificity of the nine newly developed probes was successfully demonstrated by in situ hybridization of experimentally infected amoebae and HeLa 229 cells, including HeLa 229 cells coinfected with C. pneumoniae and C. trachomatis. FISH reliably stained chlamydial inclusions as early as 12 h postinfection. The sensitivity of FISH was further confirmed by combination with direct fluorescence antibody staining. In contrast to previously established detection methods for chlamydiae, FISH was not susceptible to false-positive results and allows the detection of all recognized chlamydiae in one single step.

2000 ◽  
Vol 66 (10) ◽  
pp. 4518-4522 ◽  
Author(s):  
N. D. Gray ◽  
R. Howarth ◽  
R. W. Pickup ◽  
J. Gwyn Jones ◽  
I. M. Head

ABSTRACT Combined microautoradiography and fluorescence in situ hybridization (FISH) was used to investigate carbon metabolism in uncultured bacteria from the genus Achromatium. All of theAchromatium species identified in a freshwater sediment from Rydal Water, Cumbria, United Kingdom, which were distinguishable only by FISH, assimilated both [14C]bicarbonate and [14C]acetate. This extends previous findings thatAchromatium spp. present at another location could only utilize organic carbon sources. Achromatium spp., therefore, probably exhibit a range of physiologies, i.e., facultative chemolithoautotrophy, mixotrophy, and chemoorganoheterotrophy, similar to other large sulfur bacteria (e.g., Beggiatoa spp.).


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 7526-7526 ◽  
Author(s):  
Ahmad Sami Halwani ◽  
Zachary Burningham ◽  
Kelli Marie Rasmussen ◽  
Vikas Patil ◽  
Clarke Alan Low ◽  
...  

7526 Background: The presence of deletion 17p (del17), determined by chromosome analysis and/or fluorescence in situ hybridization (FISH), is a strong negative prognostic marker in chronic lymphocytic leukemia (CLL). Prior to the introduction of novel agents (ibrutinib, venetoclax), the clinical utility of cytogenetics/FISH was limited by the absence of chemoimmunotherapy regimens that were proven effective in patients with del17. Testing practices for chromosomal aberrations since the introduction of novel agents have not been reported. We report cytogenetic/FISH trends in a nationwide cohort of veterans diagnosed with CLL. Methods: CLL patients diagnosed 2008-2015 and receiving care at VA were identified through the VA Clinical Cancer Registry. Electronic medical records were used to determine cytogenetic/FISH testing (lab records), treatment histories (pharmacy dispensation records), and evidence of system use (heme-onc notes). Cytogenetic/FISH testing was identified by presence of specific keywords in the test name or Logical Observation Identifiers Names and Codes (LOINC) descriptions, then validated by human annotation. The testing rates are reported for the entire cohort, at time of diagnosis, time of regimen initiation (including the 12 months preceding initiation), during the novel era (2014 – 2015) and prior (2008–2013). Results: From 2008 to 2015, 3,638 CLL patients were diagnosed and received care at VA. Documented records of treatment regimens were available for 1,562 patients who received a total of 2,929 treatment regimens. Only 24% (998) of patients were tested at any point in time during their care at the VA, 17% (622) were tested at time of diagnosis, and 19% (542) of treatment courses were preceded by cytogenetic/FISH testing. No testing differences existed following the introduction of the novel agents at diagnosis (both ~ 17%), or prior to regimen initiation (20% vs 16%). Conclusions: Our study suggests CLL patients diagnosed and receiving care at the VA are not routinely undergoing cytogenetics/FISH testing at diagnosis or prior to treatment. Changing this practice pattern will personalize treatments so that del17 CLL patients receive less toxic and more effective therapies.


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