Dx: Topheceous Gout
This patient had chronic recurrent tophaceous gout. An inflammatory arthritis, gout results in red, hot, tender, and swollen joints. Over time, with chronically increased levels of uric acid, tophi form. Tophi may occur throughout the body and are painless, hard deposits of uric acid. With longstanding tophaceous deposits, bone erosion occurs, and arthritis sets in which causes joint deformities.
Acute attacks of gout cause intense pain, redness and swelling. Lower extremity joint, specifically the first metatarsalphalangeal joint (podagra), are most often affected. Spreading of inflammation causing tenosynovitis, dactylitis or cellulitis can occur. The cause is usually elevated uric acid levels, but can occur with trauma, surgery or early on in the initiation of medications to lower uric acid. Primary hyperuricemia is indefinite, and secondary is when there is excessive production or reduced renal clearance for another reason. The patient population most classically affected is middle aged males who drink alcohol and eat red meat. Hypertension, hyperlipidemia and insulin resistance are often also comorbidities. Those who already have arthritis such as osteoarthritis are also predisposed to a gouty attack and diuretic use may also contribute.
The medications used to treat gout are generally not benign, so an accurate diagnosis is important. Ideally a synovial fluid sample should be obtained and evaluated with polarizing microscopy for negatively birefringent crystals to confirm the diagnosis. It is possible for gout to co-exist with other types of arthritis (rheumatic, pseudogout, septic arthritis) which can complicate the treatment. A clinical diagnosis includes: one or more episodes of monoarticular arthritis followed by a symptom free period, maximum inflammation within one day, unilateral podagra, and tophus, hyperuricemia, advanced imaging that supports gouty erosions or tophi.(1,2) Treatment of acute attacks includes NSAIDs (Indomethacin, Ibuprofen), steroids and colchicine. Once the acute attack subsides, agents such as allopurinol and probenicid which lower uric acid concentration should be administered.
Chronic tophaceous gout occurs when solid urate is present in connective tissues forming tophi. These may be visible or palpable as in the case of our patient. Tophi may be present on the ears, bones, bursae or joint surfaces. They are often yellow or white and are not tender to palpation. When involvement spreads beyond a single joint, the entire digit becomes enlarged and can cause confusion with other disease processes. Tophi form after about 20 years of untreated elevated uric acid levels. Chronic kidney disease can cause gout, and gout can cause renal complications such as uric acid stones. Chronic urate nephropathy may also occur.
Pseudogout is distinguished from gout microscopically by having positive birefringent crystals. These crystals are made up of calcium pyrophosphate dehydrate, which is a salt, rather than uric acid. Clinically pseudogout is quite similar to gout without the predilection for often affecting the first metatarsalphalangeal joint. Treatment is also similar, with NSAIDs being the mainstay of therapy. Colchicine may also be utilized along with steroids either systemically or intra-articular. Prophylactic treatments do not work in the prevention of pseudogout attacks.
Current therapeutic agents for the treatment of gout have led to a decreased number of patients experiencing the progression to the chronic tophaceous gout stage. Recurrent and prolonged attacks of acute gouty arthritis with a shortened asymptomatic period occur if appropriate treatment is not instituted. Unfortunately, this gentleman was diagnosed with metastatic lung cancer during his admission and succumbed five months later.
1. Malik A, Schumacher HR, Dinnella JE, Clayburne GM. Clinical diagnostic criteria for gout: comparison with the gold standard of synovial fluid crystal analysis. J Clin Rheumatol 2009; 15:22.
2. Janssens HJ, Fransen J, van de Lisdonk EH, et al. A diagnostic rule for acute gouty arthritis in primary care without joint fluid analysis. Arch Intern Med 2010; 170:1120