Diagnosis of tubercular lymphadenopathy by fine needle aspiration cytology, acid-fast staining and mantoux test.

INTRODUCTION: This study was undertaken to evaluate the role of Ziehl-Neelsen stain (for acid-fas bacilli), and Mantoux test in diagnosing tubercular lymphadenopathy on FNAC.

METHODS: FNAC was performed on patient with superficial lymphadenopathy. Ziehl-Neelsen stain for acid fast bacilli was done in all cases where cheesy or purulent material was aspirated and smear showed granulomatous lymphadenitis. A Mantoux test was also done in these patients. A Mantoux test was further done in patients of reactive lymphadenopathy where the lymph node size was more than 1 cm. If the result was positive, a repeat FNAC was performed. When the repeat FNAC showed ill-defined granulomas, excision biopsy was done.

RESULTS: Tubercular lymphadenopathy was seen in 122 (48.2%) cases. Acid- fast bacilli were found in 71 (58.1%) cases. Mantoux test was positive in 112 (91.8%) cases. A repeat FNAC was done in seven of 11 patients where the cytologic features of tuberculosis were not seen but the lymph node size was more than 1 cm and Mantoux test was positive. The repeat FNAC showed ill-defined granulomas without necrosis. Excision biopsy done in these patients diagnosed them as tubercular lymphadenitis in five of the seven cases, the remaining two cases being diagnosed as reactive lymphadenitis.

CONCLUSIONS: FNAC coupled with Ziehl - Neelsen staining for AFB and Mantoux test improves the diagnostic efficiency for tubercular lymphadenopathy.