Wednesday, May 4, 2016
I had my annual TB test and the nurse read it as positive. The nurse just measured the reddened area. I then had a chest x-ray which showed calified granulomas. I went to the doctor we did a repeat TB test. This test was negative except for redness which the doctor explained I was allergic to the perservatives in the TB test. I keep getting asked why I didn`t receive medications for TB. Please can you help me solve this issue? I am currently not working because this has been a problem. Thanks.
Interpretation of TB skin tests can be quite subjective. If your TB test does not show any swelling, only redness, then your physician is correct, and there is no evidence of tuberculosis infection.
Calcified granulomas can be caused by tuberculosis infection and also by exposure to a fungal infection called histoplasmosis which is more prevalent in the US in the Ohio and Mississippi river valley's. Prior exposure to histoplasmosis could be the cause of the calcified granulomas. It is also possible that the granulomas described on your chest xray are only blood vessels.
Finally, there is also a new blood test called quantiferon, which is good when patients have borderline skin test results or have previously been vaccinated against tuberculosis. This could be used to help in your situation.
Catherine A Curley, MD, MS
Assistant Professor of Medicine
School of Medicine
Case Western Reserve University