TB Skin Test following BCG Vaccination

[whisper14222]

If a 3 year old, who was vaccinated with BCG as an infant, is given a TB skin test, what are the criteria for evaluating the reaction....would an induration of 11-12mm indicate the need for treatment with INH?

[National Jewish]

Bacille Calmette-Guerin (BCG) vaccine is given in countries with high prevalence of tuberculosis (TB).  For individuals from these areas, the history of BCG vaccination should be ignored in interpreting the reactions of the purified protein derivative (PPD) tuberculin skin test.  Thus, this 3-year-old with an 11 to 12 mm reaction needs to be considered for treatment of latent TB infection with isoniazid (INH).  This is based on the high rates of TB immigrants from areas where there is a high prevalence of TB.  This case is stronger if the child spent significant time in the country of origin.

[whisper14222]

Some additional information I should have included in my original post.

She has had 2 chest xrays in a 2 month period and both showed no abnormalities.

She has been skin tested 3 times since July and is being asked to return for another skin test and chest exray in 2 months.

She is an active, normal and healthy 3 year old and has never had any illness more serious than a cold.

Any information or suggestions would be greatly appreciated.

Thank you,

Her Concerned Grandmother!