HIV testing remains a challenge. Conventional testing with enzyme immunoassay (EIA) and confirmatory Western blot requires patient follow-up for results, which approximately 25% of patients in various outpatient testing sites fail to do. (Centers for Disease Control and Prevention. Update: HIV counseling and testing using rapid tests, United States, 1995. MMWR Morb Mortal Wkly Rep. 1998;47:211-215). Given the difficulties inherent in the transition of care from the inpatient to outpatient setting, conventional testing in the inpatient setting presents additional barriers to appropriate notification. As various point-of-care HIV tests have been developed for commercial use, the possibility of rapid HIV testing presents an opportunity to reduce notification failure and improve patient care. While not replacing traditional testing, the CDC has endorsed rapid HIV testing as a means to initiate therapy and provide counseling with a particular focus on preventing further disease transmission. In this retrospective study, Lubelchek and colleagues present the effects of a rapid HIV test utilized in the emergency department on various inpatient quality of care measures for those patients who received a positive rapid HIV test later confirmed by Western blot as compared with those patients who were diagnosed after admission by traditional diagnostic methods. This study took place in the context of CDC-funded study of the use of OraQuick (OraSure Technologies, Bethlehem, Pa.) rapid HIV testing in the emergency department at Cook County Hospital in Chicago.
The manufacturer claims the product has a sensitivity of 99.6% and a specificity of 100% as compared with conventional testing. (OraQuick rapid HIV-1 antibody test summary of safety and effectiveness. November 7, 2002. Accessed October 1, 2005, at www.fda.gov/cber/pma/P010047.htm). In the initial study, two of the three emergency department’s treatment pods were equipped to provide HIV screening utilizing the point-of-care technology to consenting patients. Patients in the third pod could be referred to rapid testing based on symptoms or risk factors. All patients who received the rapid test also submitted specimens for conventional EIA and confirmatory Western blot testing. All positive rapid HIV tests were confirmed by Western blot.
In this study, patients who were not known to be infected and were subsequently admitted on non-obstetric or surgical services over 17 months from 2003 to 2004 and confirmed to be HIV positive by Western blot were identified utilizing administrative records. Where possible, charts were reviewed to confirm no prior diagnosis of HIV. Patients who received rapid HIV testing were compared with those who only received conventional testing. Endpoints included time to primary inpatient care service awareness of HIV diagnosis, time to admission or transfer to the inpatient HIV service, time to empiric treatment of diagnosis of opportunistic infection, length of stay, discharge with appropriate prophylactic medications, discharge with patient knowledge of HIV diagnosis, and initial engagement in outpatient care. Length of stay was adjusted by multivariate regression on co-morbid diagnoses (congestive heart failure, end-stage renal disease, cirrhosis, chronic obstructive pulmonary disease, and diabetes), opportunistic infections, ICU admission, need for mechanical ventilation, and CD4 count.
A total of 103 patients were identified with complete chart review completed on 86 of them. All patients except one were admitted through the emergency department. Forty-eight patients were diagnosed initially with the rapid HIV test with 58% of these specifically referred for testing by the emergency department physician, and 55 were diagnosed with conventional testing. Overall, 78% were male, 62% African American, and 20% Hispanic. The two groups were comparable in terms of age, sex, ethnicity, history of substance abuse, HIV risk factors, psychiatric diagnoses, homelessness, CD4 count, presence of opportunistic infections, mechanical ventilation, and co-morbidities. However, conventionally tested patients were more likely to require an ICU stay (31% vs. 10%, P=.01).