| There are more than 100 different kinds of | | | | inflammation can develop and affect multiple |
| arthritis. Most of them involve inflammation. When | | | | joints. And, in cases where tophi (deposits of uric |
| a patient goes to a rheumatologist to get a | | | | acid under the skin) are present, it can be difficult |
| diagnosis, there is a process of elimination in order | | | | to distinguish from erosive RA. However, crystal |
| to arrive at the proper diagnosis. This process of | | | | analysis of joints or tophi and blood tests should |
| elimination is called "differential diagnosis." | | | | be helpful in distinguishing gout from RA. |
| Differential diagnosis can be a difficult undertaking | | | | Calcium Pyrophosphate Deposition Disease (CPPD; |
| because so many forms of arthritis, particularly | | | | Pseudogout) |
| inflammatory forms of arthritis look alike. The | | | | CPPD disease is caused by deposits of calcium |
| following is a list of types of inflammatory arthritis | | | | pyrophosphate dehydrate crystals in a joint. The |
| that can be seen and must be considered when | | | | body's reaction to these crystals, leads to |
| evaluating a patient with inflammatory symptoms | | | | significant inflammation. Diagnosis includes: |
| of arthritis. | | | | Â- Detailed medical history and physical |
| Rheumatoid Arthritis (RA) | | | | exam; |
| RA is an chronic, autoimmune, inflammatory | | | | Â- Withdrawing fluid from a joint using a |
| disease, that may affect any joint in the body but | | | | needle; |
| preferentially attacks the peripheral joints (fingers, | | | | Â- Joint x-rays to show crystals deposited |
| wrists, elbows, shoulders, hips, knees, ankles, and | | | | on the cartilage (chondrocalcinosis); |
| feet. It can also affect non-joint organ systems | | | | Â- Blood tests to rule out other diseases |
| such as the lung, eye, skin, and cardiovascular | | | | (e.g., RA or osteoarthritis). |
| system. The onset of RA may be insidious-slow- | | | | In most cases, CPPD arthritis presents with acute |
| with nonspecific symptoms, including fatigue, | | | | arthritis affecting one or more joints. However, in |
| malaise, loss of appetite, low-grade fever, weight | | | | some cases, CPPD disease can present with |
| loss, and vague aches and pains, or it may have | | | | chronic symmetric multiple joint erosive arthritis |
| an abrupt onset with inflammation involving | | | | similar to RA. RA and CPPD disease can usually be |
| multiple joints. The joint symptoms usually occur | | | | distinguished by joint fluid examination |
| bilaterally and are symmetric. Damage to joints- | | | | demonstrating calcium pyrophosphate crystals, |
| called "erosions" can be seen with magnetic | | | | and by blood tests, including RF and anti-CCP |
| resonance imaging early on or by x-ray later in | | | | antibodies, which should be negative in CCPD |
| the course of disease. Approximately 80% of | | | | arthritis. |
| patients with RA will have elevated levels of | | | | Sarcoid Arthritis |
| rheumatoid factor (RF) or anti-CCP antibodies. | | | | Sarcoidosis is an inflammatory type of arthritis. |
| Juvenile Rheumatoid Arthritis (JRA) | | | | The majority of patients with this disease have |
| JRA describes a group of arthritic conditions that | | | | lung disease, with eye and skin disease being the |
| occur in children under the age of 16. Three | | | | next most frequent signs of disease. In most |
| forms of JRA exist, including oligoarticular (1-4 | | | | cases, the diagnosis of sarcoidosis can be made |
| joints), polyarticular (> 4 joints), and | | | | on clinical and x-ray presentation alone. Patients will |
| systemic-onset or Still's disease. The latter is | | | | have acute arthritis, painful nodules under the skin |
| associated with significant internal organ | | | | on the shins (erythema nodosum), and a chest |
| involvement and may also present with fever and | | | | x-ray showing enlargement of lymph niodes. In |
| rash in addition to joint disease. Polyarticular JRA is | | | | some cases, the demonstration of a specific type |
| considered to be the type that is most similar to | | | | of inflammation change, called a noncaseating |
| adult RA, and is responsible for approximately | | | | granuloma on tissue biopsy, is necessary for |
| 30% of cases of JRA. Most children with | | | | definitive diagnosis. |
| polyarticular JRA are negative for RF and their | | | | Arthritis can be present in approximately 15% of |
| prognosis is usually good. Roughly, 20% of | | | | patients with sarcoidosis, and in rare cases can be |
| polyarticular JRA patients will have elevated RF, | | | | the only sign of disease. In acute sarcoid arthritis, |
| and these patients appear to be at more risk for | | | | joint disease is usually rapid in onset, symmetric, |
| chronic, progressive joint destruction and damage. | | | | involving the ankle joints. The knees, wrists, and |
| Uveitis- an inflammatory condition of the eye- is a | | | | small joints of the hands can be involved. In most |
| common finding in oligoarticular JRA, especially in | | | | cases of acute disease, lung and skin disease are |
| patients who are antinuclear antibody (ANA) | | | | also present. Chronic sarcoid arthritis typically |
| positive. The dangerous feature of uveitis is that | | | | involves one or maybe a few joints and due to |
| it can cause relatively few symptoms so careful | | | | its often erosive nature can be difficult to |
| screening is recommended in order to avoid | | | | distinguish from RA. |
| blindness. | | | | Polymyalgia Rheumatica (PMR) / Temporal |
| Systemic Lupus Erythematosus (SLE) | | | | Arthritis |
| SLE is a chronic inflammatory autoimmune | | | | PMR is a form of arthritis that leads to |
| disorder that can involve the skin, joints, kidneys, | | | | inflammation of tendons, muscles, ligaments, and |
| brain, and blood vessel walls. At least 4 of the | | | | tissues around the joints. It is characterized by |
| following symptoms which have been formulated | | | | large muscle (shoulders, hips, thighs, neck) pain, |
| by the American College of Rheumatology are | | | | aching, morning stiffness, fatigue, and in some |
| generally present for a diagnosis to be made: | | | | cases, fever. It can be associated with temporal |
| Â- Red, butterfly-shaped rash on the face, | | | | arthritis/giant-cell arthritis (TA/GCA) which is a |
| affecting the cheeks; | | | | related but more serious condition in which |
| Â- Typical skin rash on other parts of the | | | | inflammation of large blood vessels can lead to |
| body; | | | | complications such as blindness, aneurysms and |
| Â- Sensitivity to sunlight; | | | | cramping pain in the arms or legs (limb |
| Â- Mouth sores; | | | | claudication) due to inflammation and narrowing of |
| Â- Joint inflammation (arthritis); | | | | the large blood vessels in the chest and |
| Â- Fluid around the lungs, heart, or other | | | | extremities. PMR is diagnosed when the clinical |
| organs; | | | | picture is accompanied by elevated markers of |
| Â- Kidney dysfunction; | | | | inflammation (ESR and/or CRP). If temporal |
| Â- Low white blood cell count, low red | | | | arthritis is suspected (headache, vision changes, |
| blood cell count due to hemolytic anemia, or low | | | | limb claudication), biopsy of a temporal artery |
| platelet count; | | | | may be necessary to make the diagnosis. |
| Â- Nerve or brain dysfunction; | | | | PMR and TA/GCA can present with symmetric |
| Â- Positive results of a blood test for ANA; | | | | inflammatory arthritis similar to RA. These |
| and | | | | diseases can usually be distinguished by blood |
| Â- Positive results of a blood test for | | | | tests. In addition, headaches, acute vision changes, |
| antibodies to double-stranded DNA or other | | | | and large muscle pain are uncommon in RA, and if |
| antibodies including anti-Smith antibodies or | | | | these are present, PMR and/or TA/GCA should |
| antiphospholipid antibodies. | | | | be considered. |
| Patients with lupus can have significant | | | | Infectious Arthritis |
| inflammatory arthritis. That is why lupus can be | | | | Many infections can present with arthritis either |
| difficult to distinguish from RA, especially if other | | | | due to direct joint infection or due to autoimmune |
| signs and symptoms of lupus are minimal. | | | | joint inflammation. In most cases, infections lead |
| Inflammatory Muscle Disease | | | | to acute single joint arthritis; however, in some |
| Polymyositis (PM) and dermatomyositis (DM) are | | | | cases, chronic arthritis affecting a few or many |
| types of inflammatory muscle disease. These | | | | joints can be present. Because missed infections |
| conditions typically present with bilateral (both | | | | can lead to significant complications, it is crucial to |
| sides) large muscle weakness. In the case of DM, | | | | have a high index of suspicion for infection in any |
| rash can be a presenting sign. Diagnosis consists | | | | patient presenting with acute or chronic arthritis. |
| of four major features, including elevation of | | | | Lyme disease |
| creatine kinase (CPK), signs and symptoms such | | | | Lyme disease is an infection due to a type of |
| as muscle weakness, elevated muscle enzymes | | | | bacteria called a spirochete. The disease is |
| (creatine kinase, aldolase), electromyograph (EMG) | | | | manifested by a skin rash, swollen joints and |
| abnormalities, and a positive muscle biopsy. Often, | | | | flu-like symptoms, caused from the bite of an |
| laboratory test abnormalities can be seen including | | | | infected tick. Symptoms may include: |
| the presence of autoantibodies such antinuclear | | | | Â- A skin rash, often resembling a bulls-eye |
| antibody (ANA), and the myositis-associated | | | | (target lesion); |
| antibodies. | | | | Â- Fever; |
| In both PM and DM, inflammatory arthritis can be | | | | Â- Headache; |
| present and can look like RA -- including lung | | | | Â- Muscle pain; |
| involvement. In RA, however, unless an overlap | | | | Â- Stiff neck; and |
| syndrome - ie., a patient having both RA as well | | | | Â- Swelling of knees and other large joints. |
| as muscle disease) is present, muscle function | | | | The diagnosis of Lyme disease is typically made |
| should be normal. Also, in PM and DM, erosive joint | | | | by blood testing. If, however, chronic single joint |
| disease is unlikely. RF and anti-CCP antibodies are | | | | arthritis develops, joint fluid analysis or joint tissue |
| typically elevated in RA and not PM or DM. | | | | biopsy may be necessary for diagnosis. Lyme |
| Spondyloarthropathies (SA) | | | | arthritis can usually be distinguished from RA by |
| A group of arthritic conditions called the | | | | clinical presentation and blood tests. |
| spondyloarthropathies which include psoriatic | | | | Acute rheumatic fever (ARF) |
| arthritis, reactive arthritis, ankylosing spondylitis, | | | | Acute rheumatic fever is an inflammatory disease |
| and enteropathic arthritis are a category of | | | | that may develop after an infection with the |
| disease that cause inflammation throughout the | | | | Streptococcus bacteria (strep throat or scarlet |
| entire body, particularly in parts of the spine and | | | | fever). The disease can affect the heart, joints, |
| at other joints where tendons attach to bones. | | | | skin, and brain. Symptoms include: |
| They also can cause pain and stiffness in the | | | | Â- Fever; |
| neck, upper and lower back, tendonitis, bursitis, | | | | Â- Joint pain; |
| heel pain, and fatigue. They are often called | | | | Â- Arthritis (mainly in the knees, elbows, |
| seronegative arthritis. The term 'seronegative' | | | | ankles, and wrists); |
| means that tests for lab markers such as | | | | Â- Joint swelling; redness or warmth; |
| rheumatoid factor are negative. Symptoms of | | | | Â- Abdominal pain; |
| adult SA include: | | | | Â- Skin rash |
| Â- Back and/or joint pain; | | | | Â- Skin nodules; |
| Â- Morning stiffness; | | | | Â- A peculiar movement disorder |
| Â- Tenderness near bones; | | | | (Sydenham's chorea) |
| Â- Sores on the skin; | | | | Â- Nosebleeds; |
| Â- Inflammation of the joints on both sides | | | | Â- Heart problems, which can be |
| of the body; | | | | asymptomatic. |
| Â- Skin or mouth ulcers; | | | | The diagnosis of ARF is made by clinical |
| Â- Rash on the bottom of the feet; and | | | | assessment and blood testing for antibodies |
| Â- Eye inflammation. | | | | against streptococcal proteins. ARF and RA can |
| In some cases of SA, peripheral arthritis | | | | have similar clinical features including arthritis and |
| resembling RA can be present. Careful history and | | | | nodules. However, ARF can usually be distinguished |
| physical examination can usually distinguish | | | | from RA by clinical presentation. Rash and |
| between these syndromes, especially if an | | | | migratory arthritis are unusual in RA. The use of |
| obvious disease that is aggravating inflammation is | | | | blood tests is also helpful. |
| present (psoriasis, inflammatory bowel disease). In | | | | Viral arthritis (hepatitis B and C, parvovirus, EBV, |
| addition, since RA rarely affects the end joints of | | | | HIV) |
| the fingers (DIP joints), if these joints are involved | | | | Arthritis may be a symptom of many viral |
| from inflammatory arthritis, the diagnosis of an | | | | illnesses. This makes viral infections a great |
| SA is favored. Usually, RF and anti-CCP antibodies | | | | masquerader. The duration is usually short, and it |
| are negative in SA, although in some cases of | | | | usually disappears on its own without any lasting |
| psoriatic arthritis there may be elevations of RF | | | | effects. Clinical features in adults: |
| and anti-CCP antibodies. | | | | Â- Joint symptoms occur in up to 60%. |
| Crystal Associated Arthritis | | | | These can be symmetric and affect the small |
| Monosodium Urate Disease (Gout) | | | | joints of the hands, wrists, and ankles as well as |
| Gout is due to deposition of monosodium urate | | | | the knees. Morning stiffness is also present. |
| crystals in a joint. Gouty arthritis is typically | | | | Â- Parvovirus B19 is a very common viral |
| sudden in onset, very painful, with signs of | | | | infection that looks like RA. |
| significant inflammation on exam (red, warm, | | | | Â- Diagnosis of viral arthritis is made by |
| swollen joints). Gout can affect almost any joint in | | | | serologic testing. A high percentage of patients |
| the body, but typically affects "cooler" regions | | | | with hepatitis C may have elevated titers of RF. |
| including the toes, feet, ankles, knees, and hands. | | | | Therefore, RF testing is not helpful in distinguishing |
| Diagnosis is made by withdrawing fluid from a | | | | between hepatitis C infection and RA. However, in |
| joint and examining the fluid under a polarizing | | | | these situations, testing for anti-CCP can be |
| microscope. Patients may also have elevated | | | | helpful as anti-CCP antibodies have not been |
| serum levels of uric acid. | | | | shown to be significantly elevated in isolated |
| In most cases, gout is an acute disease that | | | | hepatitis C infections. |
| affects one joint and is easily distinguished from | | | | So as you can see... "it ain't easy... |
| RA. However, in rare cases, chronic erosive | | | | |