Don't let the TB test hold up an urgent placement in Assisted Living or Memory Care

Circumstances can arise that require a family to find immediate placement for their loved one in an Assisted Living or Memory Care residence. Many assume that once they've found an available place that meets their healthcare, financial and geographic needs, they can move in immediately.

That's rarely the case. One of the most common hold-ups is a requirement for tuberculosis (TB) testing.

Because the elderly are more susceptible to contagious disease, the CDC recommends that prior to moving from home to a communal health care setting, all potential residents undergo TB testing, within 30 days of the anticipated change of residence.

The most common test is the purified protein derivative or "PPD" test. For this test, a small amount of purified, non-infective protein from TB bacteria is injected just under the skin. If the person undergoing the test has been exposed to TB in the past, and has an inactive or "latent" infection, a localized inflammation of the skin occurs within 48-72 hours. Persons who have already had a positive PPD test in the past, or who have been vaccinated for TB previously with a "BCG" vaccine (done in some countries outside of the U.S.) should not repeat skin testing as it can cause an allergic reaction. These persons should be tested with a newer TB blood test to avoid the possibility of a generalized allergic reaction.

A negative PPD, in the absence of immunosuppression, generally, "rules out" latent and active TB. Active TB is what healthcare institutions are screening for. Active TB means that the patient has an active infection that is causing harm. This can occur anywhere in the body, but the most common type of active TB - and by far the most contagious type - occurs in the lung and is called "pulmonary tuberculosis." According to the Centers for Disease Control (CDC), while the incidence of active TB is low in the United States (2.8 cases per 100,000 people in 2018), the odds of being infected by it if living with someone with active TB is high (as great as 10%). Active pulmonary TB is spread when an actively infected patient coughs, sending millions of TB bacteria into the air. If a person is exposed in a closed environment to someone with active pulmonary TB, the odds of infection are about 10-15%. Roughly 10% of exposed patients will quickly develop active TB themselves, the risk being greater with age, overall poor health, or the presence of some other cause of an immunosuppression.

The other 90% will contain their TB infection and have no symptoms or ill effect whatsoever. Their condition is called "latent" TB. Patients with latent TB generally have a positive PPD test, but are NOT infective and constitute no threat to those with whom they live. Latent TB should not preclude the patient from placement or require further action than a chest x-ray (CXR), doctor screening for active disease, and consideration for treatment to eradicate the latent infection in younger patients.

Where does one get a TB test? How much does it cost? And what does one do if it comes out positive? Most doctors' offices can do PPD tests. So can any health department. Testing is relatively inexpensive, and in the case of health departments, often free. Ask your doctor about testing, if needed. They will interpret the results of your PPD test in 2-3 days at a follow up visit after the initial injection. If your test is positive, they will direct appropriate follow up.