I have a question and hope someone can point me in a direction of more information. My facility is in the process of considering switching from regular yearly PPD testing to two-step testing. I understand the theory behind two-step testing to be that by testing again a week or two later, that any late reaction caused from the first PPD test will be picked up when given a second PPD test. I've searched the internet, including the CDC and WHO and cannot find any information other than that some organizations "recommend" two-step testing. Does anyone have any concrete info they could share - or point me in the right direction to find it? Much thanks.
Apr 18, '01
Go to www.cdc.gov
and try your search under mantoux testing. I got several results for that including this one which specifically mentions two step testing. It is
the October 28, 1994 MMWR entitled _Guidelines for Prevention of Mycobacterium tuberculosis in health care facilities
I have also seeen a curriculum for tuberculosis control at the web site that addressed this site.
Consider also becoming a member of APIC which is an acronym for American or Association of Practitioners for Infection Control; they would have lots of helpful materials I'll bet
Apr 18, '01
A few years back (probably more like 10) when the prisons really started regularly doing ppds, we ran into this issue. The best I can recall, we obtained the information from our State Dept of Health. Why? Well, we were trying to learn if it was nurse error when several inmates showed up positive when the year before they had been negative. Of course this caused quite a stir. What we learned was this....If you have a person that has not had a TB test for years, they may not react because of the body's immune system. In short, it has gone to sleep as far as TB exposure. To retest those people at a later date, awakens the immune response (memory cells)and may give a more accurate picture of a past exposure. Indeed we found that the only ones this had happen to were those in the 50-60 age group, who had never been tested, or had not been tested since they were young, and indeed had been exposed to a grandparent, parent, etc as a child. The site you were given by mollyj on the CDC website is excellent. I may add that I work in an Infectious Disease clinic with a 100% immune compromised clientele, and we do not use the 2-step, nor do we use anergy testing any longer (this rarily is done). Hope this helps you. You may want to check under Infectious Diseases with the CDC, since TB has greatly increased with the growing numbers of HIV/AIDS infected persons.