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Context: In laboratory trials, nucleic acid amplification tests for the diagnosis of tuberculosis (TB) are more accurate than acid-fast bacilli (AFB) smear microscopy and are faster than culture. The impact of these tests on clinical diagnosis is not known.Objective: To assess the performance of a nucleic acid amplification test, the enhanced Mycobacterium tuberculosis Direct (E-MTD) test, against a uniform clinical standard stratified by level of clinical suspicion.Design: Prospective multicenter trial conducted between February and December 1996, documenting the clinical suspicion of TB at enrollment and using final comprehensive diagnosis as the criterion standard.Setting: Six urban medical centers and 1 public health TB clinic.Patients: A total of 338 patients with symptoms and signs consistent with active pulmonary TB and complete clinical diagnosis were stratified by the clinical investigators to be at low (< or =25%), intermediate (26%-75%), or high (>75%) relative risk of having TB.Main Outcome Measures: Sensitivity, specificity, and positive and negative predictive values of the E-MTD test in clinical suspicion of groups with low (n = 224); intermediate (n = 68); and high (n = 46) clinical suspicion of TB.Results: Based on comprehensive clinical diagnosis, sensitivity of the E-MTD test was 83%, 75%, and 87% for low, intermediate, and high clinical suspicion of TB, respectively, and corresponding specificity was 97%, 100%, and 100% (P = .25). Positive predictive value of the E-MTD test was 59% (low), 100% (intermediate), and 100% (high) compared with 36% (low), 30% (intermediate), and 94% (high) for AFB smear. Corresponding negative predictive values were 99%, 91%, and 55% [corrected] (E-MTD test) vs 96%, 71%, and 37% (AFB smear).Conclusions: For complex diagnostic problems like TB, clinical risk assessments can provide important information regarding predictive values more likely to be experienced in clinical practice. For this series, a clinical suspicion of TB was helpful in targeting areas of the clinical spectrum in which nucleic acid amplification tests can make an important contribution. [ABSTRACT FROM AUTHOR]

Cytomegalovirus (CMV) seroprevalence and genital tract shedding in human immunodeficiency virus (HIV)-seronegative and HIV-seropositive women from an urban minority community were investigated. CMV seropositivity was high in both groups: 181 (95.2%) of 190 HIV-negative and 158 (90.3%) of 175 HIV-positive subjects. Cervicovaginal shedding was detected in 8 (4.4%) CMV-positive HIV-negative subjects and 31 (19.6%) HIV-positive subjects (odds ratio [OR], 5.28; P < .001). Multiple logistic regression analysis revealed that CMV shedding was independently associated with younger age (OR = 0.90; P < .001) and concurrent Chlamydia trachomatis or Neisseria gonorrhoeae infection (OR = 3.60; P = .08). However, shedding was observed over a broad age range in HIV-positive subjects, with 54.8% of shedders being ⩽30 years old. Among HIV-positive subjects, CMV shedding was also associated with decreased CD4 cell counts (P =.04) and, compared with HIV-negative subjects, was significantly higher (P < .001) among subjects with CD4 cell counts <500 × 106/L (26.5% in subjects with counts ⩽200 and 22.1% in subjects with counts of 201–499 × 106/L). [ABSTRACT FROM PUBLISHER]