CRP & ASO
- 1. CRP & ASO Dr.P.B.PRAVEENKUMAR FIRST YEAR POST GRADUATE DEPARTMENT OF MICROBIOLOGY THANJAVUR MEDICAL COLLEGE
- 2. HOW TO APPROACH THIS PRACTICAL EXERCISE IN EXAM???? • AIM • PRINCIPLE • PROCEDURE • INTERPRETATION
- 3. C-Reactive protein (CRP) AIM: This test is used for the qualitative and semiquantitative in-vitro determination of inflammatory diseases.
- 4. PRINCIPLE RAPID LATEX SLIDE AGGLUTINATION TEST: Uniform latex particles are coated with anti- human CRP. The specimen containing CRP, on mixing with latex Reagent agglutinates, showing the positive test result. If CRP is absent there will be no agglutination, indicating a negative test result.
- 5. PROCEDURE QUALITATIVE METHOD: *Bring the reagents and samples to room temperature *Put three circles in slide for PC,NC & Test. *Add 25 microlitres of PC,NC & Test in corresponding circles. *Add 25 microlitres of CRP latex reagent to all three circles. *Spread it over the circle using separate sticks for each sample. *Rock the slide to and fro gently for two minutes(Not beyond 2 minutes) & See for agglutination.
- 6. INTERPRETATION OF QUALITATIVE TEST *Agglutination within two minutes – CRP POSITIVE *No agglutination / smooth suspension – CRP NEGATIVE
- 7. PROCEDURE (cont.) SEMIQUANTITATIVE METHOD: *Dilute the specimen serially in the ratio of 1:2, 1:4, 1:8, 1:16, 1:32, 1:64 using normal saline. *Add one drop of latex reagent in each of these circle. Mix well with separate applicator stick. *Rock the slide gently to and fro for two minutes and examine for agglutination.
- 8. INTERPRETATION (cont.) OF SEMIQUANTITATIVE TEST Concentration of CRP (mg/dl) = Sensitivity (0.6 mg/dl) * Titre (Highest dilution) For example: Agglutination stopped in 1:32 titre means CRP Concentration = 0.6*32 19.2 mg/dl
- 9. Anti streptolysin O (ASO) AIM: This test is used for the qualitative and semi quantitative in-vitro determination of ASO in patient serum.
- 10. PRINCIPLE LATEX SLIDE AGGLUTINATION TEST: The ASO latex is a slide agglutination test for the qualitative and semi quantitative detection of anti-streptolysin O (ASO) in human serum. Latex particles coated with streptolysin O (SLO) are agglutinated when mixed with samples containing ASO.
- 11. PROCEDURE QUALITATIVE METHOD: *Bring the reagents and samples to room temperature *Put three circles in slide for PC,NC & Test. *Add 50 microlitres of PC,NC & Test in corresponding circles. *Add 50 microlitres of ASO latex reagent to all three circles. *Spread it over the circle using separate sticks for each sample. *Rock the slide to and fro gently for two minutes(Not beyond 2 minutes) & See for agglutination.
- 12. INTERPRETATION OF QUALITATIVE TEST *Agglutination within two minutes – ASO POSITIVE (INDICATES ASO TITRE EQUAL / GREATER THAN 200 IU/ML) *No agglutination / smooth suspension – ASO NEGATIVE
- 13. PROCEDURE (cont.) SEMIQUANTITATIVE METHOD: *Dilute the specimen serially in the ratio of 1:2, 1:4, 1:8, 1:16, 1:32, 1:64 using normal saline. *Add one drop of ASO latex reagent in each of these circle. Mix well with separate applicator stick. *Rock the slide gently to and fro for two minutes and examine for agglutination.
- 14. INTERPRETATION (cont.) OF SEMIQUANTITATIVE TEST Concentration of ASO (IU/ml) = 200 * ASO titre (Highest dilution) For example: Agglutination stopped in 1:16 titre means ASO Concentration = 200 * 16
- 15. THANK YOU