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What is A 35 - year old male develops involvements of PIP, DIP and metacarpophalangeal joints with sparing of wrist and carpometacarpal joints. The probable diagnosis is: and explain in detail?
Answer is A (Psoriatic ahropathy):Psoriatic ahritis involves PIP, DIP and metacarpophalangeal joints, and may or may not involve the wrist.Involvement of DIP makes rheumatoid ahritis unlikely. DIP is spared in rheumatoid ahritis.Involvement of metacarpophalangeal joints makes osteoahritis unlikely. Metacarpophalangeal joints and carpometacarpal joint with the exception of base of thumb are spared in osteoahritis.