Cytological diagnosis and management of Bacille-Calmette-Guerin (BCG) induced lymphadenitis in infants

Introduction: Bacillus-Calmette-Guerin (BCG) is a live attenuated vaccine and used to prevent tuberculosis since 1921. The efficacy of BCG Vaccine against tuberculosis is uncertain, this vaccine is protective against the meningeal/miliary TB in childhood tuberculosis and not for adult tuberculosis. BCG vaccine is considered as a safe method of tuberculosis prevention because there are only local adverse reactions seen with this and serious complications are rare. Lymphadenitis is the most common complication of BCG vaccination. There are two forms of BCG lymphadenitis in natural course of lymphadenopathy. Simple or non-suppurative lymphadenitis which usually resolves spontaneously within a few weeks, and suppurative lymphadenitis, which characterized by appearance of fluctuation with erythema and edema of overlying skin. Materials and Methods: A total of 8 cases were included in our study, which presented to our institute in a period of one and half year, age varying from 2 months to 1 year, presented with left axillary lymph nodes. None of the child had fever/ cough or any history of weight loss or loss of appetite. FNAC was performed and smears were stained with Giemsa stain, Hematoxylin & Eosin stain (H&E) and Ziehl-Neelson (ZN) stain. Results: A total of 8 cases were studied with the mean age of 5.12 months. Majority of the patients were male with male to female ratio of 1.6:1. Out of 8 cases, only two cases had partially healed BCG scar while rest 6 cases had healed BCG scar mark with no reaction or inflammation at that site. On FNAC pus was aspirated in 50% of cases. On microscopic examination, epithelioid granulomas along with necrosis was seen in six cases, while only degenerated cells with diffuse necrosis were seen in two cases. On ZN stain acid fast bacilli were seen in 7 cases. Conclusion: Awareness about BCG induced lymphadenitis as a possible complication following BCG vaccination is necessary among parents, paramedical staff and medical practitioners is of paramount importance so that early diagnosis and effective management is done for such cases.