Exclusion of diagnosis of gout on the basis of normal uric acid level in blood

Date First Published:
July 20, 2006
Last Updated:
November 20, 2006
Report by:
Dhananjay Kumar, Specialist Registrar in A&E (The Queen Elizabeth Hospital, King's Lynn)
Search checked by:
Dhananjay Kumar, The Queen Elizabeth Hospital, King's Lynn
Three-Part Question:
In [a patient presenting with joint swelling] will [a normal serum uric acid] rule out [acute gout]?
Clinical Scenario:
A middle age male presents to emergency department with sudden onset of painful, swollen, red and tender joint at the base of big toe. Blood test showed normal serum uric acid level. There is no previous history of gout. The patient asks if he suffers from gout. Does normal serum uric acid level rules out gout?
Search Strategy:
EMBASE 1974 to date and MEDLINE 1950 to date using Dialog Datastar interface using different strategies
Search Details:
Extensive search was made in EMBASE 1974 to date and MEDLINE 1950 to date using Dialog Datastar interface using different strategies, but no relevant clinical trail or meta-analysis was found providing the answer of the question.

URIC-ACID.MJ. AND GOUT.W..MJ. AND BLOOD-CHEMICAL-ANALYSIS.MJ."- This search strategy produced 26 results but they were not relevant.

Search in EMBASE - (uric ADJ acid).TI,AB., [URIC−ACID#.DE. AND GOUT#.W..DE.] AND [(investigation OR diagnosis).TI,AB.,], repeat in MEDLINE and drop duplicates.- This search strategy produced 277 results but they were not relevant
Outcome:
No relevant clinical trail or meta-analysis was found providing the answer of the question.
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
Author Commentary:
No trials of any kind was found that was conducted to rule out gout when serum uric acid was within normal limits. On the contrarary, few studies have reported normo-uraecemia in acute gout (Urano W et al, 2002; Pittman JR et al, 1999; Snaith ML, et al 1977; Hadler N et al, 1976;). The incidence of normal serum urate has been reported varying from 12% (Park YB et al, 2003) to 39-43% (Logan JA, et al 1997, Schlesinger N, et al 1997). Despite higher levels of serum urate in gouty patients, there was no lower level of serum urate level from which gout was not diagnosed, which vindicates its removal from the New York criteria set for the diagnosis of gout (Schlesinger N, 2005; Rigby AS et al, 1994;). Demonstrating the presence of monosodium urate (MSU) crystals in the joint fluid or tophus has been the gold standard for the diagnosis of gout (Jiang GY et al,2006; Schlesinger N, 2005; O'Neill S et al, 2005; Janson R W, 2000; Perkins P et al, 1999;); and is mandatory if septic arthritis is suspected ( O'Neill S et al, 2005). Few studies have suggested that serum urate can fall during acute gout (Perkins P et al 1999; Logan JA et al, 1997).
Bottom Line:
There is no evidence supports that a normal serum urate level can exclude acute gout. Demonstrating the presence of monosodium urate (MSU) crystals in the joint fluid or tophus has been the gold standard for the diagnosis of gout. However, many physicians do not perform synovial fluid analysis. In the absence of demonstrating the presence of MSU crystals in aspirated joint fluid or tophus, clinical, radiologic, and laboratory criteria are helpful (Schlesinger N,.2005). The bottom line is that we should not exclude the diagnosis of gout on the basis of normal serum urate level.
References:
  1. Hadler N, Frank WA, Bress N, Robinson DR. Polyarticular gout
  2. Janson R W. Diagnosis and management of acute gout and symptomatic hyperuricemia.
  3. Jiang GY, Yang XL. Diagnostic evaluation and clinical characteristics of gout.
  4. Logan JA, Morrison E, McGill PE. Serum uric acid in acute gout
  5. McCarty DJ. Gout without hyperuricemia.
  6. Morrison E, McGill PE. Serum uric acid in acute gout.
  7. O'Neill S, Youssef PP, PokornyCS. How to approach the patient with a painful swollen joint.
  8. Park YB, Park YS, Lee SC, Yoon SJ and Lee SK. Clinical analysis of gouty patients with normouricaemia at diagnosis.
  9. Perkins P, Jones AC. GOUT.
  10. Pittman JR. Bross MH. Diagnosis and management of gout.
  11. Rigby AS. Wood PH. Serum uric acid levels and gout: what does this herald for the population?
  12. Schlesinger N.. Diagnosis of Gout: Clinical, Laboratory, and Radiologic Findings.
  13. Schlesinger N, Baker DG, Schumacher HR Jr. Serum urate during bouts of acute gouty arthritis.
  14. Snaith ML, Coomes EN. Gout with normal serum urate concentration.
  15. Urano W, Yamanaka H, Tsutani H, Nakajima H, Matsuda Y, Taniguchi A, Hara M, Kamatani N.. The inflammatory process in the mechanism of decreased serum uric acid concentrations during acute gouty arthritis.