Positive PPD, negative chest xray

[csully]

I had limited exposure at my workplace to a person with active, untreated TB.  She eventually died from it.  There has been no contact with this person since September, 2003.  I had the PPD test in October, 2003 and tested negative.  I was contacted by the local health dept and re-tested recently.  The PPD test was positive, however, I have no symptons.  I have a chest xray scheduled.  The health dept has advised me that I need to take the medication, regardless of the chest xray results.  I have heard conflicting information about whether the risks of the medication outweigh the benefits, if the chest xray is negative.  I am 39 years old and healthy.  I did have about 1/2 of my left kidney removed in 1986 due to a blockage in the urethra that caused atrophy in the kidney.

Please advise on the risks/benefits of the medication in the event of a negative chest xray.

[National Jewish]

The history of a negative PPD shortly after exposure (10/03), and then a positive PPD later is consistent with having been infected during contact with the TB patient.  It may take up to 16 weeks for the PPD to become reactive after exposure/infection.  If the chest xray is normal it would be appropriate to take preventive therapy or "treatment of latent TB infection" (TLTI). If you do not have underlying liver problems, there are no contraindications to TLTI. Your options include 6-9 months of isoniazid (INH) or 4 months of rifampin. All available data indicate that the potential benefits of TLTI clearly outweigh the risks.

[Ellis7]

Here's a link with details on treatment of latent TB:

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4906a1.htm
Targeted Tuberculin Testing and Treatment of Latent Tuberculosis Infection
ATS/CDC Statement Committee on Latent Tuberculosis Infection Membership List, June 2000

"This statement provides new recommendations for targeted tuberculin testing and treatment regimens for persons with latent tuberculosis infection (LTBI) and updates previously published guidelines (1,2). This statement is issued in recognition of the importance of these activities as an essential component of the TB Elimination Strategy promoted by the U.S. Public Health Service Advisory Council on the Elimination of Tuberculosis, and reports the deliberations of expert consultants convened by the American Thoracic Society (ATS) and Centers for Disease Control and Prevention (CDC). "

[selenef]

A related discussion, tb test xray negative skin results positive was started.