Fine needle aspiration diagnosis of mycobacterial lymphadenitis - Sensitivity and predictive value in the United States

OBJECTIVE: Fine needle aspiration (FNA) has proven valuable in diagnosing t uberculous lymphadenitis in countries with endemic mycobacterial infection (MI). Its role in developed countries, where sensitivity and positive predi ctive value are likely to be lower, has not been adequately explored. STUDY DESIGN: This retrospective, five-year study from a public hospital in the United States examined the predictiveness of 238 nodal FNAs in patient s with MI; 59% of patients were also HIV+. RESULTS: Diagnostic results (stainable acid-fast bacilli or positive cultur e) were present in nearly half the aspirates; sensitivity was 46%, specific ity 100%, positive predictive value (PPV) 100% and negative predictive valu e (NPV) 94%. If granulomatous inflammation (GI) was also considered a posit ive result, sensitivity increased to 53%; false positive cases of GI reduce d PPV to 80%, while specificity (98%) and NPV (95%) changed little. Conside red alone, GI had the lowest sensitivity (25%) and PPV (65%). CONCLUSION: FNA was useful in this U.S. population with MI, identifying alm ost half the affected patients. However, nondiagnostic results, such asa gr anulomatous inflammation, should be interpreted with caution.