By Betsy Todd, AJN clinical editor, MPH, RN, CIC
Mantoux skin test/CDC PHIL
Are you “PPD positive”?
In December, a California maternity nurse was diagnosed with active tuberculosis. More than 1,000 people, including 350 infants, may have been exposed. In infants, tuberculosis can be hard to diagnose and is more likely than in newly infected adults to progress to active disease and to disseminate to extrapulmonary sites. Therefore, a course of isoniazid was recommended for each of these exposed infants, as well as for any parents, visitors, or staff who tested positive after the exposure.
Some of the details of this incident weren’t released to the media. In my experience, active infection in a health care worker who has not recently traveled to a TB-endemic area is almost always the result of reactivated latent infection. That was the case in a similar exposure more than 10 years ago, when a New York City maternity nurse exposed more than 1,500 infants and adults to active tuberculosis.
And in three of the largest TB exposure investigations on which I’ve worked, the index cases were nurses in oncology, transplant, and the ED whose latent tuberculosis infection progressed to active infection. In these three cases, neither the RNs nor their own primary care providers connected their persistent febrile respiratory infections with their latent TB status.
A positive purified protein derivative (PPD) skin test or TB blood test isn’t simply a benign occupational hazard; it’s an important part of your medical history. For your own safety and that of your family, patients, and coworkers, this information should always be shared with personal health care providers.
While latent disease is most likely to become active within the first two years after infection, many factors can cause later activation, including immunosuppression from drugs or disease, poorly controlled diabetes, certain cancers, chronic renal failure, and malabsorption syndromes, including those precipitated by gastric bypass surgery. The likelihood of reactivation also increases with age. Read the rest of this entry »