The 83-year-old woman whose hands are shown in photograph A had a severe flare of arthritis in the metacarpophalangeal and proximal interphalangeal (PIP) joints after corticosteroid therapy for her asthma was stopped. The clue to the diagnosis of psoriatic arthritis is in her fingernails, which show both pitting and onycholysis.
This young boy complained of itchy lesions after he spent a day in a semiwooded area. The lesions appear urticarial, but note that the pattern of eruption is over areas of constrictive clothing: the arm of a shirt and the belt.
Abrupt onset of symmetric inflammatory arthritis and edema, as seen on the dorsum of this 72-year-old man's hand, is characteristic of remitting seronegative symmetric synovitis with pitting edema-or RS3PE. The work-up of this patient was essentially negative for other types of inflammatory arthritides.