Early symptoms of Lyme disease are not always obvious, including the notorious erythema migrans (“bullseye”) rash, which is seen in only a subset of patients. Thus, knowing additional signs of the disease is important. A November 2015 study by the American Academy of Orthopedic Surgeons suggests knee effusions, or “water on the knee,” might be an indicator of the disease even in the absence of the rash and a known tick bite. Musculoskeletal complaints are frequently associated with Lyme disease and usually prompt patients to see a physician. The authors indicate that transient episodes of spontaneous knee effusion may develop early in the disease. Unlike arthritic knees which come with significant pain, knee effusions from Lyme disease are often very large, not activity related, and mostly without pain. Physicians should keep this symptom on their radar when it presents. When diagnosed early, Lyme disease is treatable with antibiotics.
If left untreated, more than half of patients with Lyme disease will develop Lyme arthritis. Because many people with Lyme disease don’t recall getting a rash or having a tick bite, this additional tell-tale symptom of Lyme disease could help doctors make accurate diagnoses and allow patients to be treated more quickly. Read more here: http://journals.lww.com/jaaos/toc/2015/11000.