|NORMAL AND ABNORMAL BCG REACTIONS
|Kul Bhushan: NTI Newsletter 1978, 15, 65-69.
All artificial immunizations lead to more or less
specific reactions. These reactions may occur at the site of administration
of immunising agent: regionally in the area around it: at sites
far removed, in the viscera specifically concerned with immune response
and those to which the dissemination of the immunising agent may
Normal BCG Reaction: In the uninfected individuals
the reaction starts about 2-4 weeks after vaccination and all the
stages from erythema, nodule, pustule, ulcer, crust and scar formation
are over in 4-6 weeks period in that sequence at the site of BCG
vaccination. Regional lymph glands enlargement depends upon the
exact location of injection. Entire sequence of occurrences are
painless and uneventful. In previously infected persons or repeat
BCG vaccination results in exaggerated and accelerated reaction
of similar nature as described above. The reaction starts within
hours of vaccination and healing of ulcer to scar formation is over
within 2 weeks time without any lymph gland involvement. BCG organisms
are also absorbed into the blood stream and produce multiple reactions
at different sites.
Abnormal Reactions: Reactions other than
those described above or those which do not conform to the stated
time schedule are recognised as abnormal reactions or complications.
The causes of these complications are attributed to the degree
of attenuation, dose, concentration of vaccine, subcutaneous or
muscular instead of intradermal, infection of ulcer, constitution
of the subject and tuberculo hypersensitivity manifestiations anywhere
in the body. The complications are of three types. i) local, ii)
regional and iii) general. Local Complications: Undulating
ulcer, abscess formation due to deep vaccination, Eczematous lesion,
lupoid reaction and keloid formation. Regional Complications:
enlargement of lymphnode, sinus formation. General Complications:
Erythema nodosum, phlyctenular conjunctivitis, BCG Osteoitis, generalised
tuberculosis disease among children with compromised or deficient
immune system etc. The abnormal reactions are very uncommon and
many of them rare.
|KEY WORDS: BCG REACTIONS, COMPLICATIONS.