Bacillus Calmette-Guérin Adenitis: An Intriguing Series of Four Cases

Abstract

Bacille Calmette-Guérin (BCG) vaccine is part of the immunisation schedule in India. It is a live-attenuated vaccine with very few adverse reactions, one of which is BCG adenitis. The intriguing fact is that there has been a sudden upsurge in the number of BCG adenitis cases (two males and two female children), with four reported cases within three months (March 2023-June 2023). There were two male and two female children, aged between 2-8 months. All of them presented with left axillary swelling, and all but one had low grade fever only in the initial days. They all had a healed BCG vaccination scar on their left arm. Fine Needle Aspiration Cytology (FNAC) showed multiple epithelioid granulomas and, in some cases, frank caseation necrosis with the demonstration of tubercle bacilli using either Ziehl-Neelsen (Z-N) stain or Cartridge-based Nucleic Acid Amplification Test (CBNAAT). These cases mostly benefited from pus aspiration from the swelling site, with no definite role for oral antibiotics. Proper training of nursing or paramedical staff regarding vaccination technique and dosage, proper maternal and child healthcare, early detection of these cases with a high index of suspicion, as well as adequate knowledge of the treating doctors and parents/caregivers, may help in prompt management of these cases in future occurrences.