title: Systemic inflammatory markers and aspiration cell count may not differentiate bacterial from fungal prosthetic infections.
abstract: BACKGROUND
  Fungal periprosthetic joint infections (PJIs) are rare. Fewer than 200 cases have been reported in the literature. The characteristics of systemic inflammatory markers and joint aspirate cell count analysis obtained in patients with fungal PJIs have not been fully assessed. The ability to diagnose involvement of fungal PJI preoperatively may optimize the surgical and medical management of these patients.
  
  
  OBJECTIVE
  We determined whether preoperative systemic inflammatory markers and total synovial fluid leukocyte count and neutrophil percentage were different between patients with fungal and bacterial PJI.
  
  
  METHODS
  We reviewed the medical records of 44 patients with culture-positive diagnosed fungal PJIs treated at our institution between January 1, 2002, and December 31, 2011, in this study. This represented 1.2% of the total 3822 PJIs treated at our institution during the study period. The mean values for C-reactive protein, erythrocyte sedimentation rate, leukocyte count, and neutrophil percentage of patients with purely fungal PJIs were compared to those of 59 patients with bacterial PJIs treated by one surgeon during the same time period.
  
  
  RESULTS
  The mean erythrocyte sedimentation rate values for fungal and bacterial PJIs were 40 mm/hour (95% CI: 30, 50 mm/hour) and 41 mm/hour (95% CI: 33, 49 mm/hour), respectively (p=0.61). The mean C-reactive protein values for fungal and bacterial PJIs were 42 mg/L (95% CI: 22, 62 mg/L) and 65 mg/L (95% CI: 43, 88 mg/L), respectively (p=0.42). The mean total nucleated leukocyte counts for fungal and bacterial PJIs were 11,928 (95% CI: 3906, 19,950) with 81% (95% CI: 75%, 88%) neutrophils and 36,901 (95% CI: 21,822, 51,921) with 73% (95% CI: 65%, 81%) neutrophils, respectively (leukocyte count: p=0.19; neutrophil percentage: p=0.55).
  
  
  CONCLUSIONS
  Early detection of fungal PJI is needed, but systemic inflammatory markers and synovial fluid cell count analyses from aspirations do not discriminate whether an infection may be of fungal origin.
  
  
  METHODS
  Level IV, diagnostic study. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Mayo Medical School, Mayo Clinic, Rochester, MN, USA, bracken.colten@mayo.edu.
authors.forename: Colten D
authors.initials: CD
authors.lastname: Bracken
authors.forename: Elie F
authors.initials: EF
authors.lastname: Berbari
authors.forename: Arlen D
authors.initials: AD
authors.lastname: Hanssen
authors.forename: Tad M
authors.initials: TM
authors.lastname: Mabry
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Osmon
authors.forename: Rafael J
authors.initials: RJ
authors.lastname: Sierra
mesh_terms: D001170:Arthritis, Infectious / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D001424:Bacterial Infections / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis; D002452:Cell Count; D003937:Diagnosis, Differential; D042241:Early Diagnosis; D019317:Evidence-Based Medicine / Q000379:methods; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis; D007958:Leukocyte Count; D009181:Mycoses / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D009504:Neutrophils / Q000166:cytology; D011300:Preoperative Care / Q000379:methods*; D016459:Prosthesis-Related Infections / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D012189:Retrospective Studies; D013582:Synovial Fluid / Q000166:cytology*
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D002097:C-Reactive Protein
references.citation: Acta Orthop. 2013 Dec;84(6):517-23
references.pmid: 24171675
references.citation: Case Rep Orthop. 2013;2013:502728
references.pmid: 24368957
references.citation: Scand J Infect Dis. 2010 Dec;42(11-12):890-5
references.pmid: 20608769
references.citation: Am J Med. 2004 Oct 15;117(8):556-62
references.pmid: 15465503
references.citation: Indian J Orthop. 2013 Sep;47(5):526-9
references.pmid: 24133317
references.citation: Case Rep Med. 2012;2012:375682
references.pmid: 22481949
references.citation: Clin Infect Dis. 2013 Jan;56(1):e1-e25
references.pmid: 23223583
references.citation: J Arthroplasty. 2013 Feb;28(2):374.e5-8
references.pmid: 22810009
references.citation: J Arthroplasty. 2013 Feb;28(2):375.e13-5
references.pmid: 22810005
references.citation: Clin Orthop Relat Res. 2013 Sep;471(9):3002-9
references.pmid: 23633184
references.citation: Mycoses. 2003 Dec;46(11-12):462-6
references.pmid: 14641618
references.citation: J Arthroplasty. 2011 Dec;26(8):1136-8
references.pmid: 22075161