A patient presents with glomerulonephritis and has a recent…

A patient presents with glomerulonephritis and has a recent history of a sore throat which has since resolved.  The patient’s doctor suspects post-streptococcal glomerulonephritis and wants to order laboratory testing to determine if the patient has had a recent Group A streptococcal infection.  Which of the following are the BEST two tests to detect recent Group A streptococcal infection?

A patient presents with signs of secondary syphilis; there i…

A patient presents with signs of secondary syphilis; there is no past history of syphilis.  A rapid plasma reagin (RPR) screen is positive; the RPR is titered, revealing positivity at a dilution of 1:64.    Of the following, the next laboratory assay to perform is the following confirmation test: