Role of fnac in tb lymphadenitis

Background: Tuberculosis (TB), which is one of the oldest diseases known to affect humans and is a major cause of death worldwide. Primarily considered to be a pulmonary disease, TB can affect almost any organ. The term “extrapulmonary TB” has been used to describe the isolated occurrence of TB at body sites other than the lung. Lymphadenitis is the most common extrapulmonary manifestation of tuberculosis. . Over the last two to three decades, fine needle aspiration cytology (FNAC) has emerged as a simple out-patient diagnostic procedure for the evaluation of tuberculous lymphadenitis. Aims and objectives: To study cytomorphologic appearances of tuberculosis in FNAC in suspected Tuberculous lymphadenitis, to detect the presence of acid fast organism on these aspirates using Ziehl-Neelsen stain as well as correlate the cytomorphological findings with Ziehl-Neelsen staining. Material and Method: A retrospective study was done on 650 patients which presented with lymphadenopathy to Civil hospital, Ahmedabad between January 2016 to September 2016. Fine needle aspiration and routine staining with H&E, PAP and MGG was one. Also special staining with Ziehl Nelson staining was done. The slides were examined microscopically and categorised into various light microscopic patterns. The results of confirmed as well as suspicious tuberculous cases on FNAC were compared with those of AFB staining . Results: In the present study, 650 cases of lymphadenopathy were studied out which 277 cases were of tuberculosis (42.7%). 21-40 years was the most common age group involved with tuberculous lymphadenitis and females were more commonly afflicted than men (Female: Male ratio – 1.3:1). Out of all the cytomorphological patterns, Caseating Koch’s lymphadenitis is the most common. Of all the positive cases on FNAC, 71.4 % cases showed AFB positivity. Conclusion: Fine needle aspiration cytology is a safe, cheap procedure requiring minimal instrumentation and is highly sensitive to diagnose tuberculous lymphadenitis. The sensitivity can be further increased by complementing cytomorphology with acid fast staining. In acid fast staining negative cases, yield of acid fast bacilli positivity can be increased by doing Ziehl-Neelsen staining on second smear or decolourized smear revealing necrosis or by repeat