The clinical picture and join aspiration are consistent with gout. Gout results from tissue deposition of monosodium urate crystals.
Clinically, gout presents with arthritis (gouty arthritis) or tophi (chronic tophaceous gout). Gouty arthritis consists of recurrent attacks of articular and periarticular inflammation. The most common area of the body to be affected is the first toe. Chronic tophaceous gout generally takes many years to develop and can result in a chronically stiff and swollen joints. Tophi are subcutaneous nodules resulting from the deposition of crystals in the subcutaneous tissue.
Eggebeen et al. discuss that hyperuricemia is the biologic precursor to gout. However, asymptomatic hyperuricemia is common and usually does result in clinical gout. Nonsteroidal anti-inflammatory drugs or corticosteroids serve as as first-line treatments. Colchicine is second-line therapy.
Dore et al. describe the clinical diagnosis of gout without synovial fluid analysis. Using a thorough patient history and physical examination along with a serum urate measurement at the time of an acute attack and at follow-up 2 weeks later, a presumptive diagnosis of gout can be made. History and physical exam ought to reveal a sudden onset of extreme pain, tenderness, and joint inflammation. Tophi may be present on the ear, knee, or olecranon bursa.
Image A is a radiograph consistent with gout. Note the joint space narrowing of the 1st metarsalphalangeal (MTP) joint and the arrows showing medial soft tissue swelling at the 1st MTP with soft tissue radio-densities.
Illustration A shows the appearance of monosodium urate crystals under polarized light.
Answer 2: Calcium pyrophosphate deposition disease, also known as pseudogout, is the result of deposition of calcium pyrophosphate crystals. These crystals are rhomboid shaped and weakly positively birefringent.
Answer 3: Gout results from deposition of monosodium urate - not uric acid.
Answer 4: Synovial fluid aspiration in tuburculosis arthritis will be non-hemorrhagic, turbid and xanthochromic. The WBC count is moderately elevated with a predominance of polymorphonuclear leukocytes.
Answer 5: Synovial fluid aspiration is not routinely used for diagnosis of rheumatoid arthritis. Analysis may reveal decreased levels of complement factors.
Eggebeen AT. Gout: an update. Am Fam Physician. 2007 Sep 15;76(6):801-8. Review. PubMed PMID: 17910294
PMID:17910294 (Link to Abstract)
Dore RK. The gout diagnosis. Cleve Clin J Med. 2008 Jul;75 Suppl 5:S17-21. Review. PubMed PMID: 18822471.
PMID:18822471 (Link to Abstract)