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The association between human immunodeficiency virus (HIV) infection and tuberculosis (TB) mortality has been studied extensively, but the impact of HIV on other clinically relevant aspects of TB care such as TB drug-related adverse events (AEs), hospital readmissions, and TB treatment duration is less well characterized. We describe the association of HIV infection with TB clinical complexities and outcomes in a high HIV prevalence cohort in the United States. This is a retrospective cohort study among patients treated for culture-confirmed TB between 2008 and 2015 at an inner-city hospital in Atlanta, GA. Univariate analysis was used to estimate association of HIV with TB treatment interruption due to AEs, hospital readmissions, and treatment duration. Final unfavorable TB treatment outcome was defined as death, loss to follow-up, or recurrent TB. Logistic regression modeling was used to estimate association of HIV with final unfavorable outcomes. Among 274 patients with TB, 96 (35%) had HIV coinfection. HIV-positive patients had more TB treatment interruptions due to AE (34% vs. 15%), were more likely to have a hospital readmission (50% vs. 21%), and received longer TB treatment (9.9 months vs. 8.8 months) compared to HIV-negative patients ( p  < .01 for all). HIV infection was not associated with final unfavorable outcomes in univariate [odds ratio (OR) = 1.86; confidence interval (95% CI) 0.99-3.49] or multivariate analysis (aOR = 1.13; 95% CI 0.52-2.39) ( p  ≥ .05 for both). While HIV infection was not associated with final unfavorable TB outcomes, TB/HIV coinfected patients had more complex treatment course underscoring the importance of maintaining resources and expertise to treat coinfected patients in our and similar settings.

Background: Use of nucleic acid amplification tests (NAAT) for the diagnosis of Mycobacterium tuberculosis (TB) has been recommended on respiratory specimens submitted for acid-fast bacilli (AFB) testing. It also helps distinguish between TB and non-tuberculous mycobacteria (NTM) species in a setting where NTM rates are relatively high. The purposes of this study are to describe the trend and characteristics of all AFB smear-positive respiratory samples that underwent amplified Mycobacterium tuberculosis direct (MTD) testing, a type of NAAT, and to evaluate the clinical utility and necessity of the test for diagnosis of TB in a population with high-HIV prevalence., Methods: Prospective diagnostic testing and retrospective data analyses were conducted on all AFB smear-positive respiratory samples that underwent MTD testing from 2001 to 2011 at Grady Memorial Hospital (GMH), Atlanta, USA. The test performance was compared to culture., Results: A total of 2,240 AFB smear-positive specimens from 1,412 patients were tested and analyzed in the study. The proportion of specimens that were culture-positive for TB was 28.5%. Sensitivity, specificity, positive predictive value, and negative predictive value of the MTD were 99.0%, 98.0%, 95.3% and 99.6%, respectively. A downward trend was observed in the yearly numbers as well as the proportions of MTD-positive specimens during the study period (p<0.01). There were 2,027 (90.5%) specimens from patients with known HIV status, of which 70.6% was HIV positive and the majority of them (81.8%) had CD4 counts of less than 200 cells/µL. HIV-positives were more likely to have NTM compared to HIV negatives (67.7% vs. 35.4%, p<0.01)., Conclusion: Despite the decrease in the incidence of TB, NAAT continues to be an accurate and important diagnostic test in a population with high HIV prevalence, and it differentiates TB and NTM organisms.

Two novel protocols for inactivation and extraction were developed and used to identify 107 Mycobacterium clinical isolates, including Mycobacterium tuberculosis complex, from solid cultures using Vitek matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The protocol using heat inactivation with sonication and cell disruption with glass beads resulted in 82.2% and 88.8% species and genus level identifications, respectively.

We conducted a multicenter study to determine whether Mycobacterium tuberculosis complex (MTBC) cultures in automated broth-based systems could reliably be considered negative sooner than 6 weeks. Laboratory sites used Bactec MGIT or BacT/Alert and tracked results of time to detection of all mycobacteria (TTD-all, n = 1547) and of MTBC (TTD-MTBC, n = 466) over 6-month periods from primarily (93%) respiratory specimens. Cumulative percentages by day detected and median TTD of initial and follow-up specimens were analyzed. The median TTD-MTBC for MGIT (n = 6 sites) was 14 days. For laboratories using standard processing procedures, 100% of MTBC were detected from initial and follow-up specimens in 28 and 35 days, respectively, and no yield of MTBC on solid or MGIT liquid media was observed after 5 weeks. The median TTD-MTBC for BacT/Alert (n = 3 sites) was 18 days, with 95% and 100% detected within 37 and 42 days, respectively. Analysis of TTD of positive MTBC cultures in broth can predict the probability of culture negativity at defined time points. Receipt of interim negative reports earlier than 6 weeks could assist clinicians in considering alternative diagnoses and could alter the timing and prioritization of public health interventions. Laboratories should analyze their own TTD data to inform protocol decisions. Laboratories using MGIT could issue reports of no growth of MTBC on initial specimens as early as 4 weeks and for patients undergoing treatment as early as 5 weeks postinoculation.

BackgroundThe Xpert MTB/RIF (Xpert) assay is a rapid nucleic acid amplification test widely used in settings of high tuberculosis prevalence to detect tuberculosis as well asrpoBmutations associated with rifampin resistance. Data are needed on the diagnostic performance of Xpert in lower-prevalence settings to inform appropriate use for both tuberculosis detection and the need for respiratory isolation.MethodsXpert was compared to 2 sputum samples, each evaluated with acid-fast bacilli (AFB) smear and mycobacterial culture using liquid and solid culture media, from participants with suspected pulmonary tuberculosis from the United States, Brazil, and South Africa.ResultsOf 992 participants enrolled with evaluable results, 22% had culture-confirmed tuberculosis. In 638 (64%) US participants, 1 Xpert result demonstrated sensitivity of 85.2% (96.7% in participants with AFB smear-positive [AFB(+)] sputum, 59.3% with AFB smear-negative [AFB(-)] sputum), specificity of 99.2%, negative predictive value (NPV) of 97.6%, and positive predictive value of 94.9%. Results did not differ between higher- and low-prevalence settings. A second Xpert assay increased overall sensitivity to 91.1% (100% if AFB(+), 71.4% if AFB(-)), with specificity of 98.9%. In US participants, a single negative Xpert result predicted the absence of AFB(+)/culture-positive tuberculosis with an NPV of 99.7%; NPV of 2 Xpert assays was 100%, suggesting a role in removing patients from airborne infection isolation. Xpert detected tuberculosis DNA and mutations associated with rifampin resistance in 5 of 7 participants with rifampin-resistant, culture-positive tuberculosis. Specificity for rifampin resistance was 99.5% and NPV was 98.9%.ConclusionsIn the United States, Xpert testing performed comparably to 2 higher-tuberculosis-prevalence settings. These data support the use of Xpert in the initial evaluation of tuberculosis suspects and in algorithms assessing need for respiratory isolation.

Introduction: The Centers for Disease Control and Prevention has recommended using a nucleic acid amplification test (NAAT) for diagnosing pulmonary tuberculosis (TB) but there is a lack of data on NAAT cost-effectiveness. Methods: We conducted a prospective cohort study that included all patients with an AFB smear-positive respiratory specimen at Grady Memorial Hospital in Atlanta, GA, USA between January 2002 and June 2008. We determined the sensitivity, specificity, and positive and negative predictive value of a commercially available and FDA-approved NAAT (amplified MTD, Gen-Probe) compared to the gold standard of culture. A cost analysis was performed and included costs related to laboratory tests, hospital charges, anti-TB medications, and contact investigations. Average cost per patient was calculated under two conditions: (1) using a NAAT on all AFB smear-postive respiratory specimens and (2) not using a NAAT. One-way sensitivity analyses were conducted to determine sensitivity of cost difference to reasonable ranges of model inputs. Results: During a 6 1/2 year study period, there were 1,009 patients with an AFB smear-positive respiratory specimen at our public urban hospital. We found the NAAT to be highly sensitive (99.6%) and specific (99.1%) on AFB smear-positive specimens compared to culture. Overall, the positive predictive value (PPV) of an AFB smear-positive respiratory specimen for culture-confirmed TB was 27%. The PPV of an AFB smear-positive respiratory specimen for culture-confirmed TB was significantly higher for HIV-uninfected persons compared to those who were HIV-seropositive (152/271 [56%] vs. 85/445 [19%]; RR = 2.94, 95% CI 2.36–3.65, p<0.001). The cost savings of using the NAAT was $2,003 per AFB smear-positive case. Conclusions: Routine use of the NAAT on AFB smear-positive respiratory specimens was highly cost-saving in our setting at a U.S. urban public hospital with a high prevalence of TB and HIV because of the low PPV of an AFB smear for culture-confirmed TB. [ABSTRACT FROM AUTHOR]

The article discusses the case of a 45-year-old homeless woman with acquired immune deficiency syndrome (AIDS) who experienced pulmonary tuberculosis (TB) relapse with an associated resistance to antituberculous drugs isoniazid (INH) and rifampin (RIF). Her symptoms included fever, night sweats, weight loss and cough. She tested positive for Mycobacterium tuberculosis complex in August 2009, while the culture of the sputum specimen obtained at her admission indicated that the isolate was resistant to INH but susceptible to RIF. After a week, mycobacteriology laboratory findings showed that the isolate was resistant to both INH and RIF. The patient underwent injectable aminoglycoside therapy following her readmission.

Background Antiretroviral therapy (ART) for persons with HIV infection prevents tuberculosis (TB) disease. Additionally, sequential ART after initiation of TB treatment improves outcomes. We examined ART use, retention in care, and viral suppression (VS) before, during, and 3 years following TB treatment for an inner-city cohort in the United States. Methods Retrospective cohort study among persons treated for culture-confirmed TB between 2008 and 2015 at an inner-city hospital. Results Among 274 persons with culture-confirmed TB, 96 (35%) had HIV co-infection, including 23 (24%) new HIV diagnoses and 73 (76%) previous diagnoses. Among those with known HIV prior to TB, the median time of known HIV was 6 years, and only 10 (14%) were on ART at the time of TB diagnosis. The median CD4 at TB diagnosis was 87 cells/uL. Seventy-four (81%) patients received ART during treatment for TB, and 47 (52%) has VS at the end of TB treatment. Only 32% of patients had continuous VS 3 years after completing TB treatment. There were 3 TB recurrences and 3 deaths post–TB treatment; none of these patients had retention or VS after TB treatment. Conclusions Among persons with active TB co-infected with HIV, we found that the majority had known HIV and were not on ART prior to TB diagnosis, and retention in care and VS post–TB treatment were very low. Strengthening the HIV care continuum is needed to improve HIV outcomes and further reduce rates of active TB/HIV co-infection in our and similar settings. [ABSTRACT FROM AUTHOR]