The diagnosis of psoriatic arthritis is not always an easy one to make because the symptoms can easily be blamed on something else like gout, osteoarthritis or rheumatoid arthritis, and they can vary greatly from patient to patient. What a medical expert like a dermatologist or rheumatologist often has to do is put together many different clues to make the diagnosis.
Someone with psoriasis may already be in the care of a dermatologist who is mindful of the potential risk of PsA. If certain signs or symptoms arise, they may refer their patient to a rheumatologist for further examination.
Signs of PsA are usually stiffness and pain in certain joints. The pain can be prolonged in the morning (lasting 30 minutes or more) or feel worse after being immobile for a period. In addition to the joint pain and stiffness that psoriatic arthritis causes, there may also be swelling in the areas where tendons attach to bones.
Many people will, of course, first attribute these signs to something they have done, such as exercise or some other strenuous activity, unless the symptoms continue or get worse.
After reviewing a patient’s medical history, different things can be learned from a thorough physical exam. The affected joints will be examined for the key features of PsA: tendon and ligament inflammation, inflammation of the fluid-filled sheath of the joint or sausage-like swelling of an entire finger.
If PsA is suspected, and the patient does not yet have a psoriasis diagnosis or a known family history of it, a thorough examination for psoriasis will likely take place, including searching in difficult-to-see places such as behind the ear, on the scalp, in the bellybutton area and inside the buttocks. Fingernails will also be examined for signs like pitted nails that can be a sign of PsA. A patient will usually be asked about their family history of psoriasis since this is such an important predictor for both psoriasis and PsA.
It is also possible for blood tests to be ordered that can check for markers in the blood of inflammation or other markers for other diseases. The same can be done with a biopsy of fluid from an affected joint. X‑rays, ultrasounds or other imaging may also be taken to help with the diagnosis and screening questionnaires might also be used to evaluate other factors such as fatigue.< Back to My Symptoms