DETECTION OF HIV-1 BY POLYMERASE CHAIN-REACTION AND CULTURE IN SERONEGATIVE INTRAVENOUS-DRUG-USERS IN AN INNER-CITY EMERGENCY DEPARTMENT

Study background: After a health care worker's unprotected exposure to a patient's blood, the current recommendation is to obtain consent fr om the source for serologic testing for HIV. If the test is negative, no further follow-up of the exposed provider is usually indicated. Obj ective: To determine if patients testing negative for HIV-1 antibody o n routine serology harbor occult HIV-1 infection. Design: Cross-sectio nal, identity-unlinked, patient-related data and blood sample procurem ent for HIV-1 infection. Setting: Inner-city university hospital emerg ency department with high HIV-1 seroprevalence among patients. Type of participants: IV drug users not known to have HIV-1 infection. Measur ements: Serum samples were analyzed for HIV-1 antibodies by enzyme imm unoassay and Western blot. Peripheral mononuclear cells were analyzed for HIV-1 provirus by polymerase chain reaction and viral culture. Mai n results: Of 131 patients, 36 (27.5%) were Western blot-confirmed ser opositive for HIV-1. Of the 95 seronegative patients, six (6.3%) were polymerase chain reaction positive, and one of these was confirmed wit h culture. The negative predictive value of standard serology was 93.5 % with polymerase chain reaction alone and 98.9% with concordant polym erase chain reaction and culture results. Conclusion: There may be a s ignificant number of ED patients in HIV-1 prevalent populations who ha ve occult HIV-1 infection not detectable by serology at the time of a health care provider exposure. Although these data suggest that furthe r prospective study is warranted to better quantify the frequency of t his phenomenon, these preliminary data suggest that current Centers fo r Disease Control recommendations regarding provider exposures may nee d to be reappraised for certain situations.