Serology
CRP
* C-Reactive Protein * An acute phase reactant * A substance in the blood that increases as a response to an acute conditions such as infection, injury, tissue destruction * First discovered in patients that react with the C polysaccharide of pneumococcus * Produced by the Liver * Elevates during inflammation
Procedure
Significance * To check for inflammation * To determine if an anti-inflammatory drug is working * Normal levels does not always indicate no inflammation * SLE, Rheumatoid Arthritis, Scleroderma, Polymyositis and dermatomyositis can elicit no a negative result for CRP.
ASO * Anti-Streptolysin O * Antibody specific for Streptolysin O, a toxin produced by groups A, C and G streptococci * Streptolysin O causes beta hemolysis * ASO titer is used to determine a recent streptococcal infection * Measured in Todd units * 6 hour fasting is needed before blood is to be extracted
Procedure
Significance * To confirm streptococcal infection * Used as diagnosis or confirmatory test for rheumatism or scarlet fever * ASO titer is based on the neutralization of the streptococcal enzyme streptolysin O. * Some antibiotics and corticosteroids may decrease ASO antibody levels.
Reference Values * Normal Children: less than 300 Todd units * Normal Adult: less than 200 Todd units
Results
* Positive result: Agglutination * Negative result: No Agglutination * A positive result occurs in the presence of: * Bacterial endocarditis * Glomerulonephritis * Rheumatic fever * Scarlet fever * Strep throat
RHEUMATOID FACTOR * An autoantibody significant in Rheumatoid Arthritis * Antibody against the fc portion of IgG * Can also be a type2 or type 3 cryoglobulin * RF are heterogenous group of high molecular weight IgM directed against the patient’s own Ig
Procedure
Significance * Confirmatory test to differentiate Rheumatoid arthritis or Sjogren syndrome with other types of arthritis * This factor is also associated with a higher tendency to develop non-joint manifestations of rheumatoid disease, such as rheumatoid nodules and rheumatoid lung disease.
Results * Positive result: Agglutination * Negative result: No Agglutination * A negative result does not always rule out Rheumatoid Arthritis * 20% of patients with RA and Sjogren syndrome is persistently negative or shows a low level of RF.
HEPATITS B SURFACE ANTIGEN * Protein that is present on the surface of the virus; will be present in the blood with acute and chronic HBV infections * Often used to screen for and detect HBV infections * it is the primary way of identifying those with chronic infections.
Procedure
Results * HBsAg negative: no agglutination * Reported as Non-Reactive * HBsAg positive: Agglutination * Low antigen concentration: agglutination in the undiluted sample * Between medium to high: agglutination in both diluted and undiluted sample * Very high concentration: agglutination in the diluted sample
Hexagon HBsAg * Hexagon HBsAg * A 1-step qualitative detection of Hepatitis B surface antigen * The test is based on immunochromatography * HBsAg in serum/plasma reacts with the colloidal gold particles which have been coated with monoclonal mouse antibodies * The resulting complex migrates through a test area by another monoclonal Anti-HBsAg mouse antibody * The excess and unreacted complexes reacts with mouse anti-IgG antibodies of rabbit
Results * Negative result: one colored test line * C (Control) band * Positive result: two colored test lines * C (control) band * T (Test) band
