A novel evaluation of genetic polymorphism in BCG adenitis

Özet

Bacillus Calmette-Guerin (BCG) is a live attenuated vaccine which has beenused to prevent tuberculosis, according to the World Health Organization(WHO) recommendation in parts of the world with an incidence oftuberculosis infection more than 1%. The incidence of BCG adverse reactionsdiffers between regions with regional lymphadenitis as the most commonpresentation. The aim of this study was to detect the impact of polymorphismscausing BCG lymphadenitis in children receiving BCG vaccination at birth.Eight healthy infants with BCG adenitis from 4 to 12 months old wereenrolled. All these patients underwent a thorough physical examination,abdominopelvic ultrasound evaluation to detect distant lymphadenopathiesand immunodeficiency screening tests for any possible underlyingimmunodeficiency disorders. Then genotyping for known mutations wasperformed using restriction fragments length polymorphism (PCR-RFLP)assays. Sequencing was performed for IL-12 Rβ1, IFN-ϒ receptor 1, IL-10,TNF-α and P2X7.The mean age of onset of the adenitis was 6.5 months. TNF-857, IL-12Rβ1705, IL-10 1082, and IFN-ϒ- 56 single nucleotide polymorphisms (SNPs) werecommon in the children studied. The most frequent polymorphism found inthe patients with BCG adenitis except one, was the P2X7 -762 polymorphism.To conclude, these polymorphisms are more common in some ethnicpopulations but not others and make the genetic basis of immunity to BCGstrains and the occurrence of post-BCG lymphadenitis in otherwise healthychildren.