Efficacy and Safety of Conventional Transbronchial Needle Aspiration in Sarcoidosis: A Systematic Review and Meta-analysis

BACKGROUND: Flexible bronchoscopic procedures are currently the most often employed technique for demonstrating granulomatous inflammation in sarcoidosis. Conventional transbronchial needle aspiration (TBNA) has been used for over 3 decades; however, it remains an underutilized technique, primarily due to the wide variations in the reported success rates and unconfirmed safety concerns. Herein we perform a systematic review and meta-analysis of studies to estimate the diagnostic yield and safety of TBNA in sarcoidosis. METHODS: We searched the PubMed and Em Base databases for studies (1980 to January 2012) reporting the efficacy of TBNA in sarcoidosis. The quality of studies was assessed using the QualSyst tool. The efficacy of TBNA in individual studies was calculated as proportions and 95% CIs, and the results were pooled using a random effects model. Heterogeneity and publication bias were assessed for the individual outcomes. RESULTS: Our search yielded 21 studies (915 patients). The diagnostic yield of TBNA ranged from 6-90%, with the pooled efficacy being 62% (95% CI 52-71%) by the random effects model. TBNA was not associated with any major complication. The diagnostic yield increased to 83% if transbronchial lung biopsy (TBLB) was additionally performed, albeit with increased complications. There was evidence of heterogeneity and publication bias, which significantly decreased on sensitivity analysis after exclusion of retrospective studies. CONCLUSIONS: TBNA is an efficacious and safe procedure in the diagnosis of sarcoidosis. The performance of TBLB adds to the efficacy of TBNA. Hence, a combination of TBNA and TBLB should be routinely employed in diagnosis of sarcoidosis in those with enlarged mediastinal lymph nodes.