METHODS: Consented, full-time prison employees were interviewed using a structured questionnaire that included sociodemographic data, history of working in the correctional system and TB-related risk. TST was placed intradermally and read after 48-72 h. Induration size of ≥10 mm was considered positive. Logistic regression analyses were conducted to explore associations with TST positivity.
RESULTS: Of the 445 recruited prison employees, 420 (94.4%) had complete data. Most were young (median=30.0 years) men (88.8%) who had only worked at this prison (76.4%) for a median total employment period of 60 months (IQR 34.5-132.0). The majority were correctional officers, while civilian employees represented only 7.6% of the sample. Only 26 (6.2%) reported having ever been screened for TB since employment. Prevalence of TST positivity was 81% and was independently associated with longer (≥12 months) prison employment (AOR 4.9; 95% CI 1.5 to 15.9) and current tobacco smoking (AOR=1.9, 95% CI 1.2 to 3.2).
CONCLUSIONS: Latent TB prevalence was high in this sample, approximating that of prisoners in this setting, perhaps suggesting within prison TB transmission in this facility. Formal TB control programmes for personnel and prisoners alike are urgently needed within the Malaysian correctional system.
METHODS: From October 2012 to May 2013, prisoners housed in two distinct units (HIV-negative and HIV-positive) were approached to participate in the TB screening study. Consenting prisoners submitted two sputum samples that were examined using GeneXpert MTB/RIF, smear microscopy and liquid culture. Socio-demographic and clinical information was collected and correlates of active TB, defined as having either a positive GeneXpert MTB/RIF or culture results, were assessed using regression analyses.
RESULTS: Among the total of 559 prisoners, 442 (79.1%) had complete data; 28.7% were HIV-infected, 80.8% were men and the average age was 36.4 (SD 9.8) years. Overall, 34 (7.7%) had previously undiagnosed active TB, of whom 64.7% were unable to complete their TB treatment in prison due to insufficient time (<6 months) remaining in prison. Previously undiagnosed active TB was independently associated with older age groups (AOR 11.44 and 6.06 for age ≥ 50 and age 40-49 years, respectively) and with higher levels of immunosuppression (CD4 < 200 cells/ml) in HIV-infected prisoners (AOR 3.07, 95% CI 1.03-9.17).
CONCLUSIONS: The high prevalence of previously undiagnosed active TB in this prison highlights the inadequate performance of internationally recommended case-finding strategies and suggests that passive case-finding policies should be abandoned, especially in prison settings where HIV infection is prevalent. Moreover, partnerships between criminal justice and public health treatment systems are crucial to continue TB treatment after release.
DESIGN: Studies on the association between CT values and smear status were included in a descriptive systematic review. Authors of studies including smear, culture and Xpert results were asked for individual-level data, and receiver operating characteristic curves were calculated.
RESULTS: Of 918 citations, 10 were included in the descriptive systematic review. Fifteen data sets from studies potentially relevant for individual-level data meta-analysis provided individual-level data (7511 samples from 4447 patients); 1212 patients had positive Xpert results for at least one respiratory sample (1859 samples overall). ROC analysis revealed an area under the curve (AUC) of 0.85 (95%CI 0.82-0.87). Cut-off CT values of 27.7 and 31.8 yielded sensitivities of 85% (95%CI 83-87) and 95% (95%CI 94-96) and specificities of 67% (95%CI 66-77) and 35% (95%CI 30-41) for smear-positive samples.
CONCLUSION: Xpert CT values and smear status were strongly associated. However, diagnostic accuracy at set cut-off CT values of 27.7 or 31.8 would not replace smear microscopy. How CT values compare with smear microscopy in predicting infectiousness remains to be seen.