ANA Testing
In ANA testing, these cultured cells provide a wide range of nuclear antigens.
HEp‑2 cells
These syphilis screening tests detect antibodies to cardiolipin rather than the organism itself.
nontreponemal tests
This hepatitis marker indicates immunity due to vaccination.
anti‑HBs
This HIV marker is typically detectable before antibodies are formed during acute infection.
p24 antigen
This property of DNA causes it to migrate toward the red electrode during electrophoresis.
its negative charge
A high ANA titer such as 1:640 generally indicates this clinical significance.
a stronger likelihood of autoimmune disease
In the RPR card test, visible black clumps against a white background indicate this reaction has occurred.
flocculation
The presence of this antibody indicates a recent or acute hepatitis B infection.
IgM anti‑HBc
This laboratory result indicates exposure to HIV but cannot distinguish between past and current infection by itself.
positive HIV antibody test
This solution provides ions to conduct electricity during agarose gel electrophoresis.
electrophoresis buffer
This ANA fluorescence pattern is typically associated with antibodies against Anti‑double‑stranded DNA (anti‑dsDNA) antibodies and DNA-histone complexes
homogeneous pattern
In semiquantitative RPR testing, this value is reported as the patient’s titer.
the highest dilution showing visible reactivity
This hepatitis virus requires the presence of hepatitis B virus to infect a patient.
Hepatitis D
This type of HIV test is best used to monitor effectiveness of antiretroviral therapy.
HIV viral load testing
How does fragment size affect migration through an agarose gel?
Smaller fragments migrate faster and farther than larger fragments
This ANA-associated autoantibody has high specificity for systemic lupus erythematosus and produces a coarse speckled pattern.
anti‑Sm (Smith) antibody
In the reverse syphilis algorithm, a positive EIA with a negative RPR most often indicates this scenario.
past syphilis infection
This hepatitis virus is most commonly spread through IV drug use in the United States
Hepatitis C
This molecular test is required to confirm active HIV infection when screening and antibody results are discordant.
HIV‑1 RNA (NAT or PCR) testing
This buffer pH is commonly used in electrophoresis because it gives most serum proteins a net negative charge, allowing migration toward the positive electrode.
pH 8.6
A 27‑year‑old woman presents with fatigue, joint pain, and photosensitivity. ANA testing shows a homogeneous nuclear pattern at a titer of 1:640.
Systemic Lupus Erythematosus (SLE)
A 32‑year‑old man presents with a painless genital ulcer. An RPR test is reactive at 1:64. A TP‑PA test is also reactive. What is the diagnosis?
primary syphilis
What do these lab results demonstrate: HBsAg:negative, Anti‑HBs:positive, Total anti‑HBc:negative
Immune due to vaccination
A patient tests positive on a 4th‑generation HIV Ag/Ab combination assay. The HIV‑1/HIV‑2 antibody differentiation test is negative. What do these lab result indicate?
very early (acute) HIV infection, also called the window/seroconversion phase.
A 45‑year‑old woman with long‑standing rheumatoid arthritis undergoes SPEP testing. Results show a broad‑based increase across the gamma region. How should this electrophoretic pattern be interpreted?
Polyclonal gammopathy