Serology Flashcards
A 21-year-old woman presents with clinical signs and symptoms of syphilis. The venereal disease research laboratory (VDRL) test is performed and the result is negative. The physician asks for the test to be repeated using a diluted patient serum sample. This time, the result is positive. What is the most probable reason for the variation in the test results?
The patient does not suffer from syphilis
The VDRL test is invalid
The second test is incorrect due to dilution effect
The first test is incorrect due to prozone effect
The VDRL test must always be done on diluted serum
he first test is incorrect due to prozone effect
What would be the most correct conclusion if indicator cells were lysed in a complement fixation test?
Specific antibody was not added to the test system
Complement was not present in patient serum
Specific antigen was not added to the test system
Specific antibody was not present in patient serum
Complement was not added to the test system
Specific antibody was not present in patient serum
The choice of serological methodology is usually determined by the desired sensitivity or specificity of the assay. Which of the following assay techniques is considered the LEAST sensitive? Mancini Enzyme linked immunosorbent assay Agglutination Radioimmunoassay Immunofluorescence
Radioimmunoassay
Which of the following assay techniques is considered the MOST sensitive? Ouchterlony Radioimmunoassay Agglutination Immunofluorescence Enzyme linked immunosorbent assay
Enzyme linked immunosorbent assay
A patient presents with a violent allergic reaction after eating a sandwich. It is suspected that she is sensitive to the peanut in the sandwich and it is necessary to determine if there is an elevated level of IgE to peanut in her serum. Which one of the following techniques would be the most appropriate for this determination?
Mancini Radioallergosorbent test Ouchterlony Radioimmunosorbent test Complement fixation test
Radioallergosorbent test - RAST IgE
A newly married woman is planning to start a family and she is concerned about the possibility of her child developing hemolytic disease of the newborn, as she was herself born with the disease. She went to her physician who conducted some laboratory tests. What is the best advice from the physician to the patient?
She is Rh negative and should be treated postpartum with RhoGAM
She is Rh negative and there is no risk to the fetus
She is Rh positive and should be treated postpartum with RhoGAM
She is Rh positive and there is no risk to the fetus
Her husband should be tested for Rh incompatibility
She is Rh positive and there is no risk to the fetus
