Tuberculosis case finding and mortality prediction: added value of the clinical TBscore and biomarker suPAR.

SETTING: A suburban area of Bissau, the capital of Guinea-Bissau; the study was conducted among presumptive pulmonary tuberculosis (prePTB) patients seeking medical care for signs and symptoms suggestive of PTB. OBJECTIVE: To determine if a clinical TB score and a biomarker suPAR (soluble urokinase plasminogen activator receptor) have separate and composite ability to predict PTB diagnosis and mortality in prePTB patients. DESIGN: Observational prospective follow-up study conducted from August 2010 to August 2012. RESULTS: We included 1011 prePTB patients (mean age 34 years, 95%CI 33-35); 55% (n = 559) were female and 161 (16%) had human immunodeficiency virus (HIV) infection. Of all included patients, 10% (n = 101) were diagnosed with PTB. Mortality during follow-up was 5% (n = 48), with a mean survival time of 158 days (95%CI 27-289) in prePTB patients diagnosed with PTB vs. 144 days (95%CI 109-178) in those not diagnosed with PTB (P = 0.774). After adjusting for HIV status and age, the best separate predictor was suPAR 5 ng/ml, with a hazard ratio (HR) of 4.6 (95%CI 2.1-9.9) for mortality and 6.7 (95%CI 4.0-11.2) for TB diagnosis. All patients who died had a TBscore II + suPAR 7; the HR of the composite score for subsequent PTB diagnosis was 33.0 (95%CI 4.6-236.6). CONCLUSION: The proposed composite score of suPAR + TBscore II 7 can improve TB case finding and clinical monitoring.

Can tuberculosis case finding among health-care seeking adults be improved? Observations from Bissau.

SETTING: The Bandim Health Project study area in Bissau, Guinea-Bissau. OBJECTIVE: To assess the potential usefulness of predictors (elsewhere applied) and clinical scores (TBscore and TBscore II) based on signs and symptoms typical of tuberculosis (TB) in case finding. DESIGN: Observational prospective cohort study of patients with signs and symptoms suggestive of pulmonary TB (PTB) from 2010 to 2012. RESULTS: We included 1089 PTB suspects with a mean age of 34 years (95%CI 33-35); human immunodeficiency virus (HIV) prevalence was 15.1%. PTB was diagnosed in 107 suspects (76.4% sputum smear-positive, 25.2% HIV-infected). Cough > 2 weeks had the highest diagnostic ability (area under the receiver operating characteristic curve [AUC] 0.66, 95%CI 0.62-0.71), while TBscore < 3 best excluded PTB (negative likelihood ratio [LR-] 0.3) when HIV status was not known. TBscore II ≥ 3 had the highest diagnostic ability in HIV-infected PTB suspects (AUC 0.62, 95%CI 0.53-0.72), while the absence of self-reported weight loss best excluded PTB (LR- 0.2). Cough > 2 weeks as a trigger for smear microscopy missed 32.1% of smear-positive PTB cases. CONCLUSION: Case finding could be improved by screening symptomatic adults for cough and/or weight loss using TBscore II as the trigger for smear microscopy. To suspect PTB only in patients with cough > 2 weeks (non-HIV-infected) or with current cough, fever, weight loss or night sweats (HIV-infected) was not effective in patients whose HIV status was unknown at first visit.