Persistent elevation of fibrin D-dimer predicts longterm outcome in systemic juvenile idiopathic arthritis.
OBJECTIVE
We previously demonstrated that levels of fibrin d-dimer correlate with disease activity and response to therapies in systemic juvenile idiopathic arthritis (sJIA). We hypothesized that persistence of D-dimer elevation in the patterns previously described, but over a longer followup period, would signal poor outcome.


METHODS
We studied 31 children identified from 2 centers. Subjects were assigned a risk category based on their first obtained D-dimer concentration. Risk categories were based on results of our initial study, where normalization of D-dimer in patients no longer taking immunosuppressive therapy predicted good short-term outcome, and persistent D-dimer elevation while taking immunosuppressives predicted bad outcome (radiographic abnormalities, joint replacement surgery, or poor functional class) or a severe systemic manifestation. Outcome was determined at the last followup visit, a minimum of 2 years after measurement of the initial d-dimer level.


RESULTS
The 31 children were a mean 16.4 years old at an average of 8.8 years after their initial diagnosis. Ten children had a severe outcome during this period; all 10 had a study baseline risk category of "high." Of the 14 subjects who had a high risk category at study baseline, none had a mild outcome.


CONCLUSIONS
Our study indicated that a paradigm of risk of severe disease based upon persistent elevation of fibrin d-dimer on first measurements (greater than a mean of 29 months in our initial study and at least 24 months in the additional subjects) is promising to predict poor longer-term outcome in sJIA. A larger prospective study is warranted to substantiate the preliminary data and assess the relative comparative value to other biomarkers and clinical endpoints.
Bloom
Bradley J
BJ
Pediatric Rheumatology Clinic, Hasbro Children's Hospital, and Department of Pediatrics, Brown University Medical School, Providence, Rhode Island, USA. Bradley.j.bloom@pfizer.com
Alario
Anthony J
AJ
Miller
Laurie C
LC
D000293:Adolescent; D000328:Adult; D001171:Arthritis, Juvenile / Q000097:blood* / Q000175:diagnosis* / Q000628:therapy; D001175:Arthrography; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D002648:Child; D015331:Cohort Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007596:Joints / Q000276:immunology / Q000473:pathology; D008297:Male; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome; D015854:Up-Regulation / Q000276:immunology; D055815:Young Adult
D015415:Biomarkers; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D