RETROSPECTIVE DETERMINATION OF HIV-1 STATUS BY A PCR METHOD ON PARAFFIN WAX EMBEDDED SECTIONS

Aim-To develop a simple but reliable polymerase chain reaction (PCR) m ethod to determine the HIV-1 status of patients on formalin fixed, par affin wax embedded lymph node tissue. Methods-Fifty lymph node specime ns, 20 from HIV-1 seropositive and 30 from HIV-1 seronegative patients , were analysed. Lymph nodes with a variety of disease conditions were included in the study. Tissue sections were treated with a DNA extrac tion buffer containing proteinase K and the crude cell lysate was used in PCR analysis. Nested primers were used to amplify HIV-1 DNA sequen ces coding for gag, pol and env proteins. PCR products were demonstrat ed by polyacrylamide gel electrophoresis. Results were then compared w ith HIV-1 serology of the patients from whom the tissue was obtained. Results-The PCR method yielded a specificity of 100%, a sensitivity of 95%, a positive predictive value of 100%, and a negative predictive v alue of 97% when compared with HIV-1 serology. The kappa statistic (0. 958) showed an excellent agreement between the PCR method and serology . Furthermore, HIV-1 DNA was demonstrated in lymph node tissue from a serologically unconfirmed acquired immunodeficiency syndrome case necr opsied in 1982. Conclusion-This PCR method is a simple and reliable me ans of retrospectively determining the HIV-1 status of patients using formalin fixed, paraffin wax embedded lymph node tissue.