Performance of the Enzyme Linked Fluorescent Assay in Diagnosis of HIV Infection; Comparative Evaluation with other Methods.

BACKGROUND: Our study aimed to investigate the role of the enzyme linked fluorescent assay (ELFA) method in the diagnosis of Human Immunodeficiency Virus (HIV) infection by comparing it with enzyme-linked immunosorbent assay (ELISA) and chemiluminescent microplate immunoassay (CMIA) methods and its role in the HIV diagnostic algorithm and to update the recommended algorithm for HIV testing. METHODS: We evaluated 101 HIV-reactive and 101 HIV-negative specimens. All samples were studied with the methods of anti HIV1/2 test micro-ELISA, ELFA, and CMIA. At the same time, HIV RNA PCR and western blot (WB)/rapid immunochromatographic test (RICT) were also studied with the same samples. RESULTS: All HIV RNA and WB positive samples (n = 101) were positive with micro-ELISA, CMIA and ELFA. Twenty-five negative samples of HIV RNA and WB were positive with micro-ELISA and CMIA, while just 6 samples were positive with ELFA. When all samples were evaluated together, the false positivity rate of the ELFA method was found to be 5.9%, and the false positivity rates of the micro-ELISA and CMIA methods were determined to be 31.7% and 30.7%, respectively. CONCLUSIONS: It was determined that there is a high level of agreement between the ELFA method and confirmation tests. It was thought that it might take place in the preconfirmation stage. As can be seen from the results obtained, the false positive rate by ELFA method was found to be about five times lower than that of micro-ELISA and CMIA methods. Considering that antigen (p24) and antibody positivity can be given separately with this aspect, it can be considered that there is a confirmation place in HIV diagnosis algorithm.

Anti-RA 33: A Marker of Good Prognosis in Seronegative Rheumatoid Arthritis

ABSTRACT Objective: Autoantibodies are evident in the early stages of rheumatoid arthritis (RA) and play important roles in diagnosis. The aim of this study was to investigate the diagnostic capability and extent of anti-RA 33 positivity and clinical characteristics in patients with RA. Methods: We included 67 RA patients and 20 healthy subjects in our study. Duration of symptoms, duration of disease, the extent of delay in diagnosis, episodes of clinical remission, and type and number of disease-modifying antirheumatic drugs (DMARDs) taken were noted. To evaluate quality of life, the Health Assessment Questionnaire (HAQ) Disability Index (consisting of 20 questions) was applied. Disease activity was evaluated with Disease Activity Score (DAS) 28. The laboratory assessments included erythrocyte sedimentation rate, C-reactive protein level and serologic assessments for rheumatoid factor, anti-cyclic citrullinated protein and anti-RA 33. Results: The mean disease duration was 14.56 months. A total of 38 (56.7%) patients were positive for anti-RA 33 antibodies. Twenty-four (63%) of patients positive for anti-RA 33 were clinically in remission. A negative correlation was evident between anti-RA 33 positivity and number of DMARDs taken and HAQ score (r = −0,766, p < 0.001; r = −0.737, p < 0.001). A positive correlation was evident between anti-RA 33 positivity and DAS 28 score (r = 0.287, p = 0.019). Conclusion: Anti-RA 33 antibodies have poor diagnostic capability in patients with RA. Anti-RA 33 antibodies may exert helpful effects determining prognosis in established RA patients.