A 3-day delay in synovial fluid crystal identification did not hinder the reliable detection of monosodium urate and calcium pyrophosphate crystals

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Anne Kathrin Tausche - , Department of internal Medicine 3, University Hospital Carl Gustav Carus Dresden (Author)
  • Siegmund Gehrisch - , University Hospital Carl Gustav Carus Dresden (Author)
  • Ines Panzner - , University Center for Orthopedics, Trauma and Plastic Surgery, University Hospital Carl Gustav Carus Dresden (Author)
  • Maria Winzer - , University Hospital Carl Gustav Carus Dresden (Author)
  • Ursula Range - , University Hospital Carl Gustav Carus Dresden (Author)
  • Stefan R. Bornstein - , Department of internal Medicine 3, University Hospital Carl Gustav Carus Dresden (Author)
  • Gabriele Siegert - , University Hospital Carl Gustav Carus Dresden (Author)
  • Carsten Wunderlich - , University Hospital Carl Gustav Carus Dresden (Joint last author)
  • Martin Aringer - , Department of internal Medicine 3, University Hospital Carl Gustav Carus Dresden (Joint last author)

Abstract

BACKGROUND: Arthrocentesis is an essential emergency step in managing patients with acute arthritis. To identify a bacterial infection, Gram staining is performed promptly. However, crystal analysis may not be immediately performed in many facilities. Being considered not to be stable over time, synovial fluid (SF) is sometimes discarded instead of being stored for crystal identification. OBJECTIVE: The aim of this study was to assess the detectability of monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals in SF over a period of 3 days. METHODS: Consecutive SF samples from 75 joints were analyzed for MSU, CPP crystals, and pH. Two independent observers evaluated the samples by regular light and polarization microscopy immediately after arthrocentesis and after 1, 2, and 3 days at room temperature or at 4 C. RESULTS: Of 75 samples, 27 contained crystals (16 MSU, 6 CPP, 5 both); semiquantitative counts of both MSU and CPP crystals did not change significantly after 3 days. There was no new formation of crystals in any of the crystal-negative samples, which was independent of the storage temperature. Synovial fluid pH was not predictive of crystals and did not change over time. CONCLUSIONS: Although immediate workup for microbiology, including Gram stain and culture, is indispensable and well established, crystal analysis may at times not be immediately performed. Our study suggests that when crystal identification cannot be done immediately, it can be safely performed up to 3 days after arthrocentesis when SF is stored at 4 C or even at stable room temperature (20 C).

Details

Original languageEnglish
Pages (from-to)241-245
Number of pages5
JournalJournal of Clinical Rheumatology
Volume19
Issue number5
Publication statusPublished - Aug 2013
Peer-reviewedYes

External IDs

PubMed 23872540

Keywords

ASJC Scopus subject areas

Keywords

  • arthritis, crystals, gout, synovial fluid