6. Chlamydia diagnosis & treatment Flashcards
how do you diagnose chlamydia? (lab techniques)
antigen detection
what are the different types of antigen detection carried out for testing chlamydia?
immunofluorescence enzyme immunoassays (EIA) molecular methods (PCR)
how do you carry out immunofluorescence in antigen detection carried out for testing chlamydia?
specimens may be fixed to a slide, and
stained with a monoclonal antibody that is tagged with fluorescein
how are slides examined in immunofluorescence in antigen detection carried out for testing chlamydia?
examined under an UV microscpe
what are the drawbacks of immunofluorescence in antigen detection carried out for testing chlamydia?
results are subject to observer error and the method is time consuming and therefore only suitable for small numbers of specimens
what is an advantage of immunofluorescence in antigen detection carried out for testing chlamydia?
quality of specimen in terms of cells can be assessed using this technique
what does enzyme immunoassays (EIA) allow for in antigen detection carried out for testing chlamydia?
allows large numbers of specimens to be processed with relative ease
advantages of enzyme immunoassays (EIA) allow for in antigen detection carried out for testing chlamydia?
some kits have good sensitivity / specificity
the tests are relatively cheap
disadvantages of enzyme immunoassays (EIA) allow for in antigen detection carried out for testing chlamydia?
commercial kits may vary in their sensitivity and specificity
what do molecular methods (PCR) offer in antigen detection carried out for testing chlamydia?
high sensitivity and specificity
what are the disadvantages of molecular methods (PCR) in antigen detection carried out for testing chlamydia?
clinical specimens may contain inhibitors that will interfere with the assay
commercial kits may yield significant false positives and negatives
what does Chlamydia trachomatis contain relatively little of?
peptidoglycan
what is peptidoglycan the target for?
ß lactam antibiotics
what is the mainstay of treatment for Chlamydia trachomatis?
macrolides
tetracyclines
what are examples of macrolides?
erythromycin / clarithromycin / azithromycin