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Knee pain and stiffness

A 55-year-old man who had skin problems for decades sought care for pain and stiffness in both knees. His knees first started bothering him 2 years earlier, but over the past 6 months, his symptoms had worsened. The family physician (FP) noted scaling plaques on his legs and asymmetric knee swelling. The right knee had limited range of motion and there was atrophy of the leg muscles.

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The FP recognized that this patient had psoriatic arthritis, which was asymmetric in the knees and present in the patient’s hands.

The FP prescribed topical steroid ointments and referred the patient to Dermatology and Rheumatology, as it was clear that a systemic immunosuppressive agent would be needed for treatment. She ordered an interferon-gamma release assay for tuberculosis (TB) infection, hepatitis B and C serologies, and a comprehensive metabolic profile (as a baseline).

The patient was seen by Dermatology first, and a discussion of treatment choices included a review of methotrexate and various biologic medications. Fortunately, all of the baseline labs were normal and there was no evidence of exposure to TB or hepatitis.

The patient was started on methotrexate weekly to treat his psoriasis and psoriatic arthritis. Daily folic acid was prescribed to prevent the adverse effects of methotrexate. Within weeks, the patient was able to walk better and his skin had begun to clear.

Photo and text courtesy of Richard P. Usatine, MD. This case was adapted from: Chumley H, Usatine R. Arthritis overview. In: Usatine R, Smith M, Mayeaux EJ, et al, eds. Color Atlas of Family Medicine. 2nd ed. New York, NY: McGraw-Hill; 2013:562-568.

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