Lyme disease can sometimes be confused with other conditions, such as rheumatoid arthritis (RA). Both Lyme disease and RA can become debilitating if not treated.
When treated, Lyme arthritis symptoms usually go away. On the other hand, treatment for RA can slow the progression of the disease, but not cure it.
How can you tell which of these you have? In brief:
- If your arthritis symptoms are in one joint and intermittent, it may be Lyme.
- If your arthritis is in joints on both sides of your body, and pain and stiffness occur every morning, it may be RA. Having RA risk factors makes a diagnosis of RA more likely.
Lyme
Lyme disease has a known cause. It’s transmitted by the spiral-shaped bacteria Borrelia burgdorferi, which is carried by blacklegged deer ticks.
Lyme is difficult to diagnose because its wide range of symptoms mimic those of many other ailments.
If treated early with antibiotics, it can be cured. If Lyme is undiagnosed and treated late, the symptoms can become much worse, though it’s still treatable.
RA
RA’s cause isn’t known. It’s a chronic inflammatory disease affecting the lining of your joints and is thought to be a systemic autoimmune disease.
RA results in damage to your cartilage and bone that can become progressively worse if not diagnosed and treated early. The damage is irreversible. Treatment includes anti-inflammatory drugs and sometimes antibiotics.
Lyme risks
The basic risk factor for Lyme disease is living in, working in, or visiting an area where there are deer and ticks.
About 60 percent of people with untreated Lyme develop arthritis. For most people, Lyme arthritis clears up once it’s treated with antibiotics. But in some cases, the Lyme arthritis doesn’t respond to antibiotics. One
In addition, some people develop arthritis post-Lyme, including inflammatory arthritis such as RA. A 2000 study estimated that about 10 percent of adults with Lyme arthritis develop inflammatory arthritis that doesn’t respond to antibiotics.
The role of inflammatory antibodies in arthritis and Lyme isn’t well understood. In a
One study found that 10 to 20 years after Lyme arthritis, more than 50 percent of people still had positive IgM or IgG antibody responses to the Lyme bacteria. One-third of people with early Lyme disease also had positive antibody responses after 10 to 20 years.
Lyme as an RA risk
Once you have Lyme, it’s a risk factor for later developing RA and other types of inflammatory arthritis, such as psoriatic arthritis (PsA) or peripheral spondyloarthritis.
In a
If you see a Lyme rash and get treated immediately with a sufficient course of antibiotics, it’s
RA risks
Having a high level of IgM antibodies is a risk factor for RA. These presence of these antibodies, known as rheumatoid factors (RF), can result in an immune response that attacks healthy tissue. IgM antibodies are not well understood, and they are also found in people with other infections.
Another marker for RA is having anti-cyclic citrullinated peptide (anti-CCP) antibodies in your blood.
Specific risk factors for RA include:
- Smoking. This is a strong risk factor for RA, especially for more severe RA.
- Obesity. This is especially significant in people diagnosed with RA under age 55.
- Family history of autoimmune disease.
- Female sex. Women are two to three times more likely to develop RA than men.
- Occupational exposure to dust and fibers.
- Genes. RA isn’t inherited, but you may have a genetic susceptibility that increases your risk of developing RA.
- Hormones. Hormonal and environmental factors, including infections and trauma, may be involved.
It’s interesting that moderate alcohol intake may reduce the risk of RA.
Lyme symptoms
Lyme arthritis symptoms include achy, stiff, or swollen joints. Usually only one joint is affected — most often a knee. Smaller joints or tendons or bursae may also be affected. The arthritis pain may be intermittent.
Lyme has many other symptoms in addition to arthritis. These can include:
- an initial bull’s-eye or irregular red rash
- fatigue
- flu-like symptoms
- night sweats
- cognitive decline
- neurological problems such as trouble balancing or Bell’s palsy
- sensitivity to light
- cardiac disease (carditis)
RA symptoms
Early symptoms of rheumatoid arthritis include:
- joint stiffness on both sides of the body, especially in the morning or after inactivity
- swollen, tender, or warm joints
- smaller joint involvement, such as fingers and toes
- decreased range of motion
- fatigue
- loss of appetite
About 40 percent of people with RA have symptoms that don’t involve the joints. RA can seriously affect your eyes, skin, heart, and lungs.
| Lyme | RA | |
| Joint involvement | •Usually on one side only •Large joints involved (most often a knee) •May impact more than one joint | Usually hands, feet, and wrists on both sides (bilateral) |
| Other symptoms | Many diverse symptoms that mimic those of other diseases | General feeling of unwellness |
| Diagnosis | •Standard tests not always accurate •Often done by symptoms and response to antibiotics | Can be difficult, especially when there’s a history of Lyme |
| Duration of symptoms | Intermittent and variable | May fade and flare |
| Pain | Mild to severe | •Mild to severe •Joint stiffness for more than an hour in the morning |
| Antibiotic response | In most cases, symptoms respond | Sometimes RA responds to antibiotics, but this isn’t understood and not FDA-approved |
| Infection involvement | Tick bite sometimes with coinfections | Suspected, but not proven |
| Other | Can be severe if not treated | Risk factors may include smoking, exogenous hormonal use, reproductive factors, family history of autoimmune diseases, and obesity |
Lyme and Lyme arthritis
Lyme arthritis is sometimes the first symptom of Lyme. A course of antibiotics will often clear up the arthritis symptoms.
Antibiotics may be given orally or intravenously, depending on the severity of Lyme symptoms.
When Lyme arthritis occurs in the post-infection stage of Lyme, anti-inflammatory drugs such as methotrexate may be used.
RA
The standard treatment for RA includes anti-inflammatory agents such as:
- nonsteroidal anti-inflammatory drugs
- conventional or biologic disease-modifying anti-rheumatic drugs (DMARDS)
Both Lyme and RA have a better outcome the sooner they are diagnosed and treated.
Lyme
Most people don’t see the initial Lyme rash, and the diversity of possible symptoms makes diagnosis difficult. If you have symptoms of arthritis and could have been bitten by a tick, see your doctor to rule out Lyme. It’s best to find a Lyme-aware doctor.
RA
RA also can be difficult to diagnose. If your joints regularly are stiff for an hour or more after you wake up, see your doctor. It could be RA.