Bizarre Outbreak of Tuberculosis Linked to Donated Bone Grafts, CDC and FDA Officials Say

Bizarre Outbreak of Tuberculosis Linked to Donated Bone Grafts, CDC and FDA Officials Say
A photomicrograph of the rod-shaped bacteria Mycobacterium tuberculosis, responsible for its namesake disease. (Image: Elizabeth S. Mingioli/CDC)

A contaminated batch of donated bone tissue is the likely source behind a strange outbreak of tuberculosis, according to federal health officials at the U.S. Centres for Disease Control and Prevention as well as the U.S. Food and Drug Administration. As many as 113 people who went in for spinal repair surgery are thought to have been exposed to the bacterial disease through the products.

In early June, the FDA announced a voluntary recall from Aziyo Biologics concerning a single lot of their FiberCel product, which is used as a bone graft to promote healing following surgery or injuries like serious fractures. The recall came after a customer complaint from a single hospital where seven out of 23 patients had developed an infection after surgery in which the FiberCel was used; four of these patients would then test positive for tuberculosis. FiberCel and similar products are made from human tissue, and the tainted lot had come from a single donor cadaver.

This weekend, the CDC announced that it was now looking into the matter, calling it a multi-state outbreak of TB associated with the products. It’s not clear exactly how many confirmed cases of TB have been reported, but it’s known that the bone grafts were shipped to 20 states between April and May this year and that they were used in at least 113 people before the recall was initiated, according to the Washington Post. Eight patients died after their surgery, but it’s not confirmed whether TB played a part in any of these deaths. In its announcement, the CDC stated that all unused products from the lot have since been sequestered.

Tuberculosis is a now-rare disease in the U.S. caused by Mycobacterium tuberculosis. Though it typically infects the lungs, the bacteria can invade many other parts of the body, including the bone and spine. Typical acute symptoms include fever, chills, and coughing up blood. Without antibiotic treatment, TB often becomes latent, not causing symptoms in people until their health starts to decline for other reasons. But in less healthy or immunocompromised people, it can cause serious, life-threatening illness. Outside of the U.S., it remains one of the more common and deadliest diseases in the world, killing upwards of a million people annually. Antibiotic resistance has also allowed some TB infections to become increasingly hard to get rid of, though most cases are still treatable.

Because of the danger posed by TB spreading to areas outside of the lungs, especially the spine, the CDC is recommending that all patients who received these grafts be treated with antibiotics. And though no other FiberCel lots are suspected of being tainted at this point, the CDC has said that it is now “working closely with health departments, hospitals, and surgical centres in the affected states” and the FDA to prevent further harm and future outbreaks.

However this outbreak came to be, it’s probably a very rare risk. Though grafts and similar donated materials are screened for many infectious diseases, TB isn’t one of them. And according to the CDC, the last documented case of TB linked to donated bone was reported in 1953, which is likely a reference to this case study in The Journal of Bone and Joint Surgery published that same year.

In that paper, British orthopaedic surgeon J. I. P. James detailed four cases of spinal tuberculosis linked to rib bones taken from TB patients who had undergone rib removal surgery — a last resort and brutal attempt at a cure for the disease practiced between the 1930s and 1950s, before antibiotics were in wide use.