Utility of CBNAAT, Cytology and Histology in diagnosis of suspected tubercular solid lymph node

Abstract

Cytology, Ziehl Neelsen staining and Mantoux test are conventionally used to test and treat lymph node tuberculosis. Cartridge Based Nucleic Acid Amplification Test (CBNAAT) is being now recommended for diagnosis of all extrapulmonary tuberculosis including tubercular lymphadenitis.To asses efficacy of various diagnostic tools for diagnosis of lymph node tuberculosis in solid state (non-caseating stage).It was a prospective study conducted by including all consecutive patients with lymph node swelling suggestive of tuberculosis. Fine needle aspirate was subjected for cytology and CBNAAT. If both turned negative, excision biopsy was performed and subjected for histology. Results were tabulated.Sixty patients were included after excluding certain patients with caseous aspiration. Thirty-one (51.67%) had mycobacterium detected in CBNAAT. Remaining patients after histology had following diagnosis; Tuberculosis in eight, nonspecific reactive hyperplasia in 11, metastasis and lymphoma in four and Non Tubercular Mycobacteria and actinomycosis in one each patient. CBNAAT is an effective tool for diagnosing lymph node tuberculosis even in early stages of pathology. Relying solely on cytology to diagnose tuberculosis should be discouraged.