Lyme disease is a bacterial infection contracted from the bite of a disease-carrying tick. The causative bacterium is Borrelia burgdorferi. The symptoms of the various stages of Lyme disease mimic some of the common symptoms of the autoimmune disease systemic lupus erythematosus, more commonly known as lupus. Establishing the correct diagnosis involves examining the evolution of the symptoms, looking for distinguishing characteristics of the respective illnesses, and reviewing laboratory test results.
The American College of Rheumatology notes arthritis as a symptom of both lupus and chronic Lyme disease. With both illnesses, the affected joints are painful and swollen. Chronic Lyme disease commonly affects the knees and, less commonly, other large joints. Lupus arthritis may also affect the knees, although the smaller joints of the hands, wrists, ankles and toes are also commonly involved. The arthritis of both lupus and chronic Lyme disease is cyclic; that is, it is present for a time and then remits. This is in stark contrast to other forms of arthritis such as rheumatoid arthritis and osteoarthritis, which are chronic and progressive.
Whereas the Lupus Foundation of American reports approximately 90 percent of people with lupus experience joint or muscle pain during the course of the illness, the National Institute of Allergy and Infectious Diseases states only 10 to 20 percent of people with chronic Lyme disease develop arthritis.
“The Merck Manual for Healthcare Professionals” lists fever as a symptom of both lupus and Lyme disease. Fever is most prominent with early-stage Lyme disease, and is less common with chronic Lyme disease. Intermittent fevers are a more persistent feature of lupus, typically occurring when the disease flares.
The Mayo Clinic notes fatigue presents as a common symptom of both Lyme disease and lupus. Lyme disease-associated fatigue is common during the early stages of the disease. It may persist in untreated patients who develop chronic Lyme disease. Lupus-associated fatigue is usually unrelenting and profound. Dr. D. Robinson, Jr. reported in a 2010 “Arthritis Care and Research” article that fatigue is a frequent health problem for nearly 90 percent of persons living with lupus.
The Centers for Disease Control and Prevention (CDC) lists headache as a symptom of Lyme disease. This symptom may persist in people who remain untreated and develop chronic infection. The Lupus Foundation of American notes headache is also a common symptom of lupus, which often affects the blood vessels of the head, precipitating headaches.