The single hot joint.
Several points may be stressed.  (1)When in doubt, perform joint aspiration and look for crystals of micro-organisms. A joint tap is nearly always indicated.  (2)Do not rely on a coincidental elevated serum uric acid level.  Question the patient regarding drug therapy and other causes of secondary hyperuricemia.  (3)Examine all of the patient, looking for tophi (gout), skin lesions (gonococcal infection, psoriasis), erythema nodosum (allergic reactions, fungal infections), and other clues.  (4)Monoarticular rheumatoid arthritis is a rare cause of a single hot joint, but it is much more common that the real rarities (e.g., pigmented willondular synovitis).  (5)Anky-losing spondylitis and Reiter's syndrome are common, yet frequently overlooked.  (6)Radiologic examination is usually not helpful.  (7)Having ruled out infection, crystal synovitis, and hemorrhage, it is sufficient to introduce symptomatic treatment and await the natural development of the joint disease.  Follow-up in four to six weeks and simple blood studies often reveal the definitive diagnosis.  Most of the time, natural healing processes are effective , and reward the patience of the conservative physician.  Blind management must always be avoided.
D000328:Adult; D000368:Aged; D001168:Arthritis / Q000150:complications; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006073:Gout / Q000175:diagnosis; D006470:Hemorrhage / Q000150:complications; D006801:Humans; D007592:Joint Diseases / Q000209:etiology / Q000628:therapy; D008875:Middle Aged; D010003:Osteoarthritis / Q000150:complications; D010019:Osteomyelitis / Q000150:complications; D010020:Osteonecrosis / Q000150:complications; D013585:Synovitis / Q000150:complications; D052256:Tendinopathy / Q000150:complications; D014947:Wounds and Injuries / Q000150:complications