Author: Anonymous

The most specific assays for human chorionic gonadotropic (hCG) use antibody reagents against which subunit of hCG?

An anaerobic gram-negative bacillus isolated from blood culture following bowel surgery grew smooth, white nonhemoltyic colones. A Gram stain showed pale, bipolar-staining rod with rounded ends. Bile stimulated growth of the organism and catalase was produced. The isolate was not inhibited by colistin, vancomycin; indole was not produced. The most likely identification of this organism is:

The cyst state may be recovered from formed fecal specimens submitted for parasitic examination if the specimen:

An immunofluorescence microscopy assay (IFA) was performed (ex. ANA testing for patterns), and a significant antibody titer was reported. Positive and negative controls performed as expected. However, the clinical evaluation of the patient was not consistent with a positive finding. What is the most likely explanation of this situation? 

A yellow pigment producing organism that is oxidase positive, nonmotile, and does not grow on MacConkey agar is:

A gram positive spore forming bacillus growing on sheep blood agar anaerobically produces a double zone of beta hemolysis and is positive for lecithinase. What is the presumptive identification?

Testing of the patient’s serum with a panel of O cells for unexpected antibodies can demonstrate:

The smallest concentration of antimicrobial agent which prevents growth in subculture or results in 99.9% decrease of the initial inoculum, is the definition of:

What is the purpose of adding 0.025%-0.050% sodium polyanethol sulfonate (SPS) to nutrient broth media for the collection of blood cultures?

A negative PYR (L-pyrolidonyl-alpha-napthylamide) test is demosntrated by: