Examination Of Combined Two Synthetic Peptides ELISA Assay To Detect EB Virus Antibody In Nasophryngeal Carcinoma

OBJECTIVE To study the application of EBNA1 and VCA-P18 combined peptide-coated ELISA (EBNA1+VCA-P18) detect EB virus antibody in the serological diagnosis of nasopharyngeal carcinoma (NPC), looking for an easy, efficient and economical method for serological diagnosis of early nasopharyngeal carcinoma. METHODS Single and combined synthetic peptides were coated, establish ELISA assay to compare and analysis 120 cases of pathologically confirmed nasopharyngeal carcinoma and 180 healthy human serum. Using EBNA1+VCA-P18/IgA coated ELISA detection methods and domestic VCA/IgA ELISA kit can be compared. RESULTS EBNA1+ VCA-P18/IgA sensitivity (95.8%) and specificity (87.2%) than domestic VCA/ IgA kit (80.8%,83.8%); its false positive rate (12.8%) and false negative rate (4.0%) were significantly lower than the kit VCA/IgA (16.2%,19.2%); its positive predictive value (83.3%),negative predictive value (96.9%) and the Youden index (0.832) were higher than VCA/IgA kit (77.0%,86.8%,0.646). EBNA1+VCA-P18/IgA coated ELISA method sensitivity (95.8%) higher than EBNA1/IgA (80.8%) and VCA-P18/IgA (83.3%); its specificity (87.2%) lower than EBNA1/IgA (89.4%) and VCA-P18/IgA (87.8%); its false positive rate (12.8%) higher than EBNA1/IgA (10.6%) and VCA-P18/IgA (12.2%), the false negative rate (4.0%) lower than EBNA1/IgA (12.5%) and VCA-P18/IgA (16.7%); its positive predictive value (83.3%) higher than VCA-P18/IgA (82.0%), lower than EBNA1/IgA (84.7%); also its negative predictive value (96.9%) and Youden index (0.832) higher than EBNA1/IgA (91.5%,0.769), and VCA-P18/IgA (88.8%,0.711). Compare the 120 cases of nasopharyngeal carcinoma patients, found that male and female in the comparison of different indicators were not statistically significance; VCA-P18/IgA in the two age groups was difference between two age groups(P=0.028), EBNA1/IgA, EBNA1+VCA-P18/IgA between the two age groups was not significant difference; compare different TNM stage, EBNA1/IgA, VCA-P18/IgA, EBNA1+VCA-P18/IgA within three indicators were not significant difference; EBNA1/IgA and VCA-P18/IgA in different clinical stage of the difference were statistically significant (P=0.031,0.021, VCA-P18 was heterogeneity of variance), while EBNA1+VCA-P18/IgA in different clinical stage was not significant difference (P=0.821) CONCLUSION The ELLISA using combined synthetic peptide EBNA1+VCA-P18/IgA have a higher sensitivity and specificity, also simple and inexpensive for people in the early diagnosis and screening of NPC.