Clinical significance of cultures collected from fine-needle aspiration biopsy

The rate of positive cultures in fine-needle aspiration biopsy (FNAB) specimens is evaluated, and the value of submitting FNAB culture is assessed. Review of 3,300 FNAB specimens from 2,416 patients were tabulated for culture results, when obtained from the FNAB material. For positive culture results, clinical impact was assessed. Of 3,300 FNAB specimens and 2,416 patients, 185 had cultures performed (6% of specimens, 8% of patients). Of the 185 cultured specimens, 63 (34%) were positive and 122 (66%) were negative. Of the 63 positive cultures, 23 (12% of all FNAB cultures) had a significant impact on patient care. In our institution the FNA culture rate is 6%. When cases with clinical or microscopic suspicion of infection are cultured, 34% are positive for aerobic or anaerobic bacteria, mycobacteria or fungus. Culture in FNA specimens is a useful adjunct to diagnosis and impacts care in 12% of patients cultured at FNAB. This method can be used to triage patients with suspected infectious diseases and can aid in managing patients who may have recurrent infections.