U.S. officials are investigating an unusual outbreak of tuberculosis (TB) infections in people who had spinal surgery. They suspect the culprit is a potentially tainted bone repair product, according to news reports.
More than 100 people may have been exposed to TB bacteria through this product, called FiberCel, during spinal surgeries that occurred this spring, according to The Washington Post. FiberCel is a putty-like substance made from human bone tissue that's used during various orthopedic and spinal surgeries, the Post reported.
Early this month, the maker of FiberCel, Aziyo Biologics Inc., issued a recall of a single lot of the product after one hospital reported that seven out of 23 patients who received FiberCel developed post-surgical infections, and four of these tested positive for TB, according to the recall notice from the Food and Drug Administration (FDA).
The recalled lot came from a single donor cadaver, and it had been shipped to 20 states, according to a statement from Aziyo Biologics. A total of 113 patients received the recalled product, with most suspected TB cases in Indiana and Delaware, the Post reported.
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According to the Centers for Disease Control and Prevention (CDC), which is investigating the outbreak along with the FDA, these 113 patients "are likely to have been exposed to MTB" or Mycobacterium tuberculosis, the bacteria that causes TB. The CDC is recommending that all patients who received the recalled product should undergo treatment for TB, which typically involves taking antibiotics for six to nine months.
Although Mycobacterium tuberculosis typically attacks the lungs, "TB bacteria can attack any part of the body such as the kidney, spine and brain," according to the CDC. The bacteria typically spreads from person to person through the air. However, most people who are infected with TB have "latent TB," in which the immune system keeps the infection at bay and people don't develop symptoms. But if a TB infection becomes "active," the bacteria can grow, and the disease can be fatal if untreated. People with weakened immune systems are at greater risk of developing an active TB infection.
The spread of TB through bone grafts is extremely rare — so rare that regenerative medicine companies such as Aziyo Biologics are not required to test their bone products for TB bacteria, according to the Post. The last time a case of TB transmission like this occurred was in 1953, the Post reported.
Officials are currently investigating how the FiberCel product may have become contaminated, the Post reported.
Originally published on Live Science.