Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by persistent joint pain, swelling, and stiffness. It can also affect the skin, heart, lungs, and eyes.
Rheumatoid arthritis differs from some other forms of arthritis because it affects both sides of the body. The most common form of arthritis, osteoarthritis, may affect only one side of the body and is a degenerative condition that happens over time.
The diagnosis of rheumatoid arthritis uses a combination of clinical, laboratory, and imaging information. There is no single test that is used to diagnose rheumatoid arthritis.
Laboratory studies used to diagnose rheumatoid arthritis include:
- Erythrocyte sedimentation rate (ESR)
- C-reactive protein (CRP) level
- Complete blood count
- Rheumatoid factor (RF) assay
- Antinuclear antibody assay (ANA)
- Anti−cyclic citrullinated peptide (anti-CCP) and anti−mutated citrullinated vimentin assays
- HLA tissue typing
- Lyme disease, to rule out Lyme as a cause for the symptoms
- Uric acid, to rule out gout
Imaging studies used to diagnose rheumatoid arthritis include:
- X-rays (first choice): Hands, wrists, knees, feet, elbows, shoulders, hips, cervical spine, and other joints as indicated
- Magnetic resonance imaging (MRI): Primarily cervical spine
- Ultrasound of joints: Joints, as well as tendon sheaths, changes and degree of vascularization of the synovial membrane, and even erosions
Joint aspiration and analysis of synovial fluid may be indicated, including:
- Gram stain
- Cell count
- Culture
- Assessment of overall appearance
What Are Symptoms of Rheumatoid Arthritis?
The first signs and symptoms of rheumatoid arthritis tend to come on gradually, often before joint pain or stiffness is noticeable, and may include:
- Muscle pain
- Fatigue
- Weight loss
- Numbness and tingling in the hands
- Low-grade fever
- Feeling unwell (malaise)
Joint pain and stiffness usually starts in the small joints, such as the joints at the base of the fingers, the middle of the fingers, and the base of the toes, or it may occur in a single, large joint, such as the knee or shoulder, or it may shift from one joint to another
Rheumatoid arthritis usually affects the same joints on both sides of the body (symmetrical). As the condition progresses, joint pain and inflammation become more noticeable and symptoms include:
- Joint pain and stiffness that may affect the:
- Hands
- Finger deformities/bent fingers
- May result in carpal tunnel syndrome, which causes weakness, tingling, and numbness in the hand and fingers
- Wrist: difficulty bending the wrist backward
- Elbow: swelling may result in numbness or tingling in the fingers
- Shoulder: pain and limited motion
- Knee: difficulty bending the knee and development of a “Baker's cyst,” which is a fluid-filled cyst in the space at the back of the knee
- Ankle: nerve damage may occur, leading to numbness and tingling in the foot
- Foot: tenderness at the joints at the base of the toes may cause someone to stand and walk with weight on the heels. The top of the foot may be swollen and red, and the heel may be painful.
- Hips: difficulty walking
- Neck: painful and stiff, difficulty bending the neck and turning the head
- Cricoarytenoid joint: inflammation of a joint near the windpipe that can cause hoarseness and difficulty breathing
- Hands
- Other symptoms of rheumatoid arthritis may include:
- Bone loss/decreased bone density
- Muscle weakness
- Skin problems
- Rheumatoid nodules (painless lumps that appear beneath the skin)
- Eye problems
- Redness
- Pain
- Vision problems
- Lung disease
- Shortness of breath
- Dry cough
- Pericarditis: inflammation of the tissue around the heart that can cause chest pain and difficulty breathing
- Vasculitis: inflammation of the blood vessels
- Sjögren's syndrome
- Dry eyes
- Dry mouth
What Causes Rheumatoid Arthritis?
It is unknown what causes rheumatoid arthritis but it is thought that susceptibility factors and initiating factors may affect a person's risk of developing the condition:
Susceptibility factors increase a person’s susceptibility to developing rheumatoid arthritis when exposed to risk factors that initiate the inflammatory process. Susceptibility factors include:
- Age: middle-aged or older
- Female sex: twice as likely as men to develop RA
- Genetics: people with a relative who has RA have an increased risk of developing the condition
Initiating factors (triggers) increase the chances a susceptible person will develop the disease, such as:
- Infection: bacteria in the gut or mouth and gums infection (periodontitis) in particular are risk factors
- Smoking
- Stress
What Is the Treatment for Rheumatoid Arthritis?
Medications used to treat rheumatoid arthritis include:
- Nonbiologic disease-modifying antirheumatic drugs (DMARDS)
- Azathioprine (Imuran)
- Cyclosporine (Gengraf, Neoral)
- Gold salts
- Hydroxychloroquine (Plaquenil)
- Leflunomide (Arava)
- Methotrexate (Rheumatrex, Trexall, Otrexup)
- Minocycline (Dynacin, Minocin)
- Penicillamine (Cuprimine, Depen)
- Sulfasalazine (Azulfidine)
- Biologic tumor necrosis factor (TNF)–inhibiting DMARDs
- Adalimumab (Amjevita, Cyltezo, Humira, Hadlima, Hyrimoz, Adalimumab-atto, Adalimumab-adbm, Adalimumab-bwwd, Adalimumab-adaz)
- Certolizumab (Cimzia)
- Etanercept (Enbrel, Erelzi, etanercept-szzs)
- Golimumab (Simponi, Simponi Aria)
- Infliximab (Remicade, Inflectra, infliximab-dyyb, Renflexis, infliximab-abda, Ixifi, infliximab-qbtx)
- Biologic non-TNF DMARDs
- Abatacept (Orencia)
- Anakinra (Kineret)
- Baricitinib (Olumiant)
- Rituximab (Rituxan)
- Sarilumab (Kevzara)
- Tocilizumab (Actemra)
- Tofacitinib (Xeljanz, Xeljanz XR)
- Upadacitinib (Rinvoq)
Other medicines used to treat rheumatoid arthritis include:
- Corticosteroids
- Methylprednisolone (Depo-Medrol, Medrol, Solu-Medrol)
- Prednisolone (Orapred ODT, Pediapred)
- Prednisone (Prednisone Intensol, Rayos)
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
- Ibuprofen (Advil, Motrin), available over-the-counter (OTC)
- Celecoxib (Celebrex)
- Diclofenac (Voltaren, Cambia)
- Ketoprofen
- Naproxen (Naprosyn, Aleve, Anaprox, Anaprox DS, Naprelan)
- Pain relievers (analgesics)
- Acetaminophen (Tylenol)
- Tramadol (Ultram)
- Topical skin products
- Diclofenac topical (Voltaren)
Surgical treatments for rheumatoid arthritis include:
- Synovectomy
- Tenosynovectomy
- Tendon realignment
- Reconstructive surgery or arthroplasty
- Arthrodesis
Other therapies for rheumatoid arthritis include:
From 
Rheumatoid Arthritis Resources
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