CRP and tuberculosis: Therefore, although we were unable estimate the predictive accuracy of diagnostic results within all subgroups PWTS, our cohort-wide results suggest that a negative diagnostic result on any of several widely available diagnostic tests – CXR, CRP, and repeat Ultra – could support deferring treatment for an otherwise low-risk patient whose estimated probability of TB after the initial trace result is near a clinician’s treatment threshold (Supplemental Table 4).