title: Relationship between crevicular aspartate aminotransferase levels and periodontal disease progression.
abstract: BACKGROUND
  Aspartate aminotransferase (AST), an enzyme released from necrotic cells, has been identified in gingival crevicular fluid (GCF), and elevated levels are associated with periodontal tissue destruction. The aim of this study was to examine the relationship between elevated GCF levels of AST and periodontal disease progression.
  
  
  METHODS
  Over a 12-month period, 8 to 10 interproximal sites in 41 periodontitis subjects (PS) and 15 healthy subjects (HS) were monitored. Clinical measurements included relative attachment level (RAL), probing depth, and bleeding on probing (BOP). Semiquantitative levels of GCF AST (< 800 microIU, > or = 800 microIU, and > or = 1,200 microIU) were determined using a chairside assay. At the 6- and 12-month visits, scaling and root planing and prophylaxis were performed in the PS and HS, respectively. Sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) were calculated for 2 diagnostic criteria (AST > or = 800 microIU, AST > or = 1,200 microIU) utilizing 4 thresholds of disease progression as determined by 2 methods (absolute change in relative attachment level and cumulative sum [CUSUM]).
  
  
  RESULTS
  The percentage of sites exhibiting AST > or = 800 microIU, AST > or = 1,200 microIU, and BOP in the PS was significantly (P<0.02) lower at 6 and 12 months compared to baseline. The use of crevicular AST activity to monitor periodontal disease progression was associated with many false-positive results. Overall, low specificities, PPV, and odds ratios were demonstrated by the assay when using 2 diagnostic criteria and 4 thresholds of disease progression. The high NPV suggest that a negative AST test result was indicative of a periodontally stable site.
  
  
  CONCLUSIONS
  These results demonstrate that elevated levels of AST were present at sites that did not subsequently exhibit disease progression. The high prevalence of AST-positive sites due to gingival inflammation diminished the test's ability to discriminate between progressive and stable, but inflamed, sites.
authors.affiliation: Department of Periodontics, State University of New York at Stony Brook, 11794-8703, USA. roringer@epo.hsc.sunysb.edu
authors.forename: R J
authors.initials: RJ
authors.lastname: Oringer
authors.forename: T H
authors.initials: TH
authors.lastname: Howell
authors.forename: M L
authors.initials: ML
authors.lastname: Nevins
authors.forename: D S
authors.initials: DS
authors.lastname: Reasner
authors.forename: G H
authors.initials: GH
authors.lastname: Davis
authors.forename: J
authors.initials: J
authors.lastname: Sekler
authors.forename: J P
authors.initials: JP
authors.lastname: Fiorellini
mesh_terms: D000328:Adult; D001219:Aspartate Aminotransferases / Q000032:analysis*; D016009:Chi-Square Distribution; D016001:Confidence Intervals; D003777:Dental Prophylaxis; D012534:Dental Scaling; D018450:Disease Progression; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D005883:Gingival Crevicular Fluid / Q000201:enzymology*; D005884:Gingival Hemorrhage / Q000201:enzymology / Q000503:physiopathology; D005891:Gingivitis / Q000201:enzymology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D017622:Periodontal Attachment Loss / Q000201:enzymology / Q000503:physiopathology; D010514:Periodontal Pocket / Q000201:enzymology / Q000503:physiopathology; D010518:Periodontitis / Q000201:enzymology / Q000503:physiopathology* / Q000628:therapy; D010519:Periodontium / Q000201:enzymology; D011237:Predictive Value of Tests; D016745:Root Planing; D012680:Sensitivity and Specificity; D016037:Single-Blind Method
chemical_list: D001219:Aspartate Aminotransferases