What is the optimal diagnostic pathway in tuberculous lymphadenitis in the face of increasing resistance: Cytology or histology?

BACKGROUND

The London Borough of Newham has the highest rates of tuberculosis (TB) within Europe (116 per 100,000). There is a lack of guidance in lymph node (LN) TB on how to best obtain a positive culture, which is the gold standard in the face of increasing mycobacterial resistance.

METHODS

An individual cohort study was carried out via a prospective local TB database capturing 90 cases of cervical LN TB over 34 months. We compared the diagnostic efficacy of fine needle aspiration (FNA) and excision biopsy of LN.

RESULTS

FNA cytology revealed granulomata in 49%, acid-fast bacilli (AFB) in 8.6% and a positive culture in 40%. LN excision showed granulomata in 97.6%, AFB in 17.1% and a positive culture in 70.1%. There was an 18% resistance to first-line antimicrobials.

CONCLUSIONS

We describe our experience and suggest an algorithm for the culture of TB organisms to avoid a lengthy diagnostic process.