Psoriatic arthritis (PsA) is an inflammatory arthritis that occurs mainly in people with psoriasis. PsA affects around 30 percent of patients with psoriasis and approximately 500,000 Americans. Inflammatory arthritis refers to a condition that causes joint pain, joint swelling, and joint stiffness. PsA is a part of a larger group of arthritis-types called the spondyloarthropathies. These include ankylosing spondylitis, reactive arthritis, inflammatory bowel disease-associated arthritis, and undifferentiated spondyloarthritis.
PsA can also affect the tendons (such as the achilles tendon) particularly at the site where a tendon (or ligament) inserts onto a bone (known as the enthesis). The pattern of joints involved in PsA varies considerably from person to person. Some people may have only one joint involved, some may have 2-3 joints involved, and others may have many joints involved similar to patients with rheumatoid arthritis (RA). Patients with PsA may have arthritis in the sacroiliac joints which can lead to low back or buttock pain or stiffness. The cause of psoriatic arthritis is unknown. It can occur at any age and women and men are affected equally.
Symptoms of PsA and the Spondyloarthropathies
Signs and Symptoms of PsA and the spondyloarthropathies include:
- Joint Swelling
- Joint Pain
- Joint tenderness
- Warmth of the joint
- Stiffness of the joints, neck or back upon awakening in the morning or after prolonged periods of rest or inactivity
- Swelling, redness and severe pain in an entire finger or toe such that it looks like a sausage ("sausage digit" or dactylitis)
- Weakness of the arms or legs
Diagnosing PsA and the Spondyloarthropathies
There are no blood tests that can diagnose PsA. The CASPAR (CIASsification of Psoriatic ARthritis) criteria are often used to define psoriatic arthritis in clinical trials. These criteria require that a patient have inflammatory arthritis (swelling in the joint), enthesitis (inflammation where a tendon or ligament inserts onto the bone) or spondylitis (inflammation in the spine) and at least three points from the following:
- Evidence of current psoriasis (diagnosed by a rheumatologist or dermatologist) or personal history of psoriasis (2 points), OR family history of psoriasis (1 point).
- Typical psoriatic nail dystrophy (pitting of the nails or breaking a part of the nails) on current physical examination (1 point)
- Sausage Digit (known as dactylitis) on exam or recorded by a rheumatologist (1 point)
- Negative rheumatoid factor (1 point)
- X-ray evidence of new bone formation in the hands or feet (excluding osteophytes, the type of new bone formation found in osteoarthritis) (1 point)
Penn Psoriatic Arthritis Program
The Penn Psoriatic Arthritis program is directed by Alexis Ogdie-Beatty, MD, MSCE. The goals of the Penn Psoriatic Arthritis Program are:
- To provide outstanding clinical care to patients with psoriatic arthritis.
- To investigate the etiology of psoriatic arthritis and the best treatment options.
- To educate both patients and rheumatology fellows about the disease.
Drs. Alexis Ogdie and Jonathon Dunham work extensively with Penn Dermatologists who focus on the care of patients with psoriasis including Joel Gelfand, MD, MSCE, Abby Van Voorhees, MD, and Junko Takeshita, MD, PhD, as well as other local dermatologists, to provide the best care for our patients with psoriatic arthritis from a multidisciplinary perspective.
Dr. Ogdie-Beatty and Gelfand are currently studying cardiovascular outcomes in patients with psoriatic arthritis and methods of early detection of psoriatic arthritis in patients with psoriasis. Dr. Ogdie-Beatty and Dr.Takeshita are working to identify better methods of capturing patient reported outcomes in the medical record. In addition, Dr. Ogdie-Beatty is studying the use of various imaging tests in the diagnosis of PsA.
Clinical Trials in Psoriatic Arthritis
Penn Rheumatology is not currently enrolling for psoriatic arthritis clinical trials, but there are other observational studies (no intervention) and imaging studies open for enrollment.
Find out more about psoriatic arthritis and spondyloarthropathies at: