Value of FDG-PET/CT for treatment response in tuberculosis: a systematic review and meta-analysis

Purpose Tuberculosis (TB) is an infectious disease with a high global incidence and substantial disease burden. Monitoring disease activity and evaluating treatment response with conventional methods such as culture or chest x-ray is time-consuming and non-specific. Active TB lesions are typically highly FDG-avid and may be assessed on whole-body 18-fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). We hypothesized that FDG-PET or FDG-PET/CT is useful for evaluation of treatment response and outcome in TB-infected patients undergoing anti-tuberculosis therapy (ATT). Methods PubMed and Embase databases were searched and original studies with humans infected with Mycobacterium tuberculosis receiving ATT and a minimum of one FDGPET/CT or FDG-PET scan were included. Percentage change in maximum standardized uptake value (SUVmax) from baseline was assessed with a fixed-effects model using the inverse variance method supplemented by a Forest Plot. Publication bias and heterogeneity between studies was assessed with a Funnel plot and the I squared statistic, respectively. Results A total of 2048 articles were identified and nine were included in the review. Four studies were included in the meta-analysis. The estimated overall percentage change in SUVmax was - 54.38% (95% confidence interval -57.81 to -50.96) and the heterogeneity between studies was high (I-2 = 90.1%). Study design, protocol, sample size and ATT varied between studies. Conclusion Despite high heterogeneity there was a trend towards the usefulness of FDG-PET or FDG-PET/CT for evaluation of ATT response. Impending research is needed to further clarify the predictive value of FDG-PET/CT in tuberculous disease.