ABSTRACT
BACKGROUND: Isoniazid preventive therapy (IPT) prevents tuberculosis (TB) in people living with HIV (human immunodeficiency virus, PLWH). Symptom screening without chest radiographs (CXRs) was established as the strategy for excluding TB disease among PLWH seeking IPT in Botswana's 2001 pilot project. This strategy was evaluated in 2004-2006 among candidates screened for an IPT clinical trial. METHODS: PLWH referred from clinics and HIV testing centers were screened for TB symptoms. All asymptomatic candidates received CXRs; those with abnormal CXRs were investigated further. RESULTS: Among 2732 asymptomatic candidates screened, 302 (11%) had abnormal CXRs potentially compatible with TB; TB disease was diagnosed in 43 of these 302 (14%), or 43 (1.6%) of the 2732 asymptomatic candidates. While not associated with CD4 lymphocyte counts < 200 cells/mm(3), TB was associated with a positive tuberculin skin test (relative risk 2.1, 95%CI 1.1-4.0). IPT was initiated in 113 (62%) of 182 asymptomatic PLWH with abnormal CXRs; 8/113 (7%) subsequently developed TB, and 7/8 (88%) successfully completed anti-tuberculosis treatment. CONCLUSIONS: The prevalences of abnormal CXRs and TB were respectively 2.6- and 8.9-fold higher among asymptomatic PLWH screened for the trial than in the pilot. A cost-effectiveness analysis is needed to determine whether the benefits of symptom screening alone are offset by the risk of inducing INH resistance by excluding CXRs during screening.
Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , HIV Infections/complications , Mass Screening/methods , Tuberculosis/diagnosis , AIDS-Related Opportunistic Infections/diagnostic imaging , Adult , Antitubercular Agents/therapeutic use , Botswana/epidemiology , CD4 Lymphocyte Count , Clinical Trials as Topic , Female , Humans , Isoniazid/therapeutic use , Male , Mass Chest X-Ray/methods , Pilot Projects , Prevalence , Treatment Outcome , Tuberculin Test , Tuberculosis/etiology , Tuberculosis/prevention & controlABSTRACT
To exclude tuberculosis, WHO/UNAIDS recommends considering medical history, symptom screen, and chest radiograph before starting tuberculosis prevention in people infected with HIV. The value of a chest radiograph for this purpose is unknown. We prospectively assessed 935 HIV-infected outpatients seeking isoniazid preventive therapy. Of 935 patients, 692 (74%) had no signs or symptoms of tuberculosis. Of these 692, 123 (18%) were lost during the chest radiograph process, and one (0.2%) of the remaining 563 was diagnosed with tuberculosis on the basis of the chest radiograph. A screening chest radiograph should not be required routinely for asymptomatic people taking isoniazid as preventive treatment in settings able to screen for signs and symptoms of tuberculosis.
