Induction of HLA-B27-Associated Reactive Arthritis After a Wharton's Jelly "Stem Cell" Injection.

Orthobiologic injections are an emerging treatment option for musculoskeletal conditions. Allogenic gestational tissue-derived products, including umbilical cord-derived Wharton's jelly, are among the available options. These tissues are currently being harvested and sold by companies as an off-the-shelf "stem cell" injection for conditions such as back pain and osteoarthritis. Despite documented infections from similar umbilical cord derivatives, "stem cell clinics" continue to use them. Here, we report the first documented case of HLA-B27-associated reactive arthritis induced by a Wharton's jelly stem cell injection. A 36-yr-old man was injected with Wharton's jelly for low back pain and within 24 hours developed fevers, chills, polyarthritis, and enthesitis. Infectious disease work-up was negative. Inflammatory markers were elevated and his HLA-B27 antigen was positive. Initial treatment included methylprednisolone and sulfasalazine. This case highlights the unknown dangers of these allogenic injections and physicians should remain cautious about their use until further study and regulation can ensure patient safety.