summary Pseudogout is a common form of inflammatory arthritis caused by intra-articular calcium pyrophosphate dihydrate crystal deposition and presents with attacks of joint pain, joint stiffness and swelling. Diagnosis is made by joint aspiration and crystal analysis showing weakly positively birefringent rhomboid-shaped crystals Treatment is usually medical management with NSAIDs. Epidemiology Demographics commonly affects the elderly rarely affects younger patients, unless occurring in conjunction with other disease Etiology Associated conditions hemochromatosis hyperparathyroidism SLE gout RA Wilson's disease hemophilia long term hemodialysis can cause a pyrophosphate like deposition disorder chondrocalcinosis is present in 7% of patients Mimics gout except affects older patients > 60 years old affects more proximal joints positively-birefringent crystal Presentation Symptoms acute, onset joint tenderness warm, erythematous joint commonly on knee (most common) and wrist joints (2nd most common) Physical exam erythematous, monoarticular arthritis joints tender to palpation may observe superficial mineral deposits under the skin at affected joints Imaging Radiographs may see calcification of fibrocartilage structures (chondrocalcinosis) TFCC in wrist meniscus in the knee Evaluation Joint aspiration crystal analysis weakly positively birefringent rhomboid-shaped crystals Treatment Acute pseudogout nonoperative NSAIDS splint intra-articular steroids splints for comfort Chronic pseudogout nonoperative intraarticular yttrium-90 injections colchicine ( 0.6 mg PO bid for recurrent cases) prophylactic colchine can help to prevent recurrence Complications Can result in permanent damage to the joints and renal disease