A 65-years old man develops the onset of severe knee pain over 24 hours. The knee is red, swollen and tender. He has a history of diabetes mellitus and cardiomyopathy. An X-ray of the knee shows linear calcification. Definitive diagnosis is best made by which of the following? 1- Serum uric acid 2- Serum Calcium 3- Arthrocentesis and identification of positively birefringent rhomboid crystals 4- Rheumatoid factor 5- ANA From: Pre Test Medicine 12th
Answer: Arthrocentesis and identification of positively bire Answer: Arthrocentesis and identification of positively birefringent rhomboid crystals