TY - JOUR
T1 - Development and initial validation of the MS score for diagnosis of macrophage activation syndrome in systemic juvenile idiopathic arthritis
AU - Pediatric Rheumatology international Trials Organization, the Childhood arthritis &Rheumatology Research alliance, the Pediatric Rheumatology Collaborative study Group and the Histiocyte society
AU - Minoia, Francesca
AU - Bovis, Francesca
AU - Davì, Sergio
AU - Horne, Anna Carin
AU - Fischbach, Michel
AU - Frosch, Michael
AU - Huber, Adam
AU - Jelusic, Marija
AU - Sawhney, Sujata
AU - McCurdy, Deborah K.
AU - Silva, Clóvis A.
AU - Rigante, Donato
AU - Unsal, Erbil
AU - Ruperto, Nicolino
AU - Martini, Alberto
AU - Cron, Randy Q.
AU - Ravelli, Angelo
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Objective To develop and validate a diagnostic score that aids in identifying macrophage activation syndrome (MAS) in patients with systemic juvenile idiopathic arthritis (sJIA). Methods The clinical and laboratory features of 362 patients with sJIA-associated MAS and 404 patients with active sJIA without evidence of MAS were collected in a multinational collaborative project. Eighty percent of the study population was used to develop the score and the remaining 20% constituted the validation sample. A Bayesian Model Averaging approach was used to assess the role of each clinical and laboratory variables in the diagnosis of MAS and to obtain the coefficients of selected variables. The final score, named MAS/sJIA (MS) score, resulted from the linear combination of these coefficients multiplied by the values of each variable. The cut-off that best discriminated MAS from active sJIA was calculated by means of receiver operating characteristic (ROC) curve analysis. Score performance was evaluated in both developmental and validation samples. Results The MS score ranges from-8.4 to 41.8 and comprises seven variables: central nervous system dysfunction, haemorrhagic manifestations, active arthritis, platelet count, fibrinogen, lactate dehydrogenase and ferritin. A cut-off value ≥-2.1 revealed the best performance in discriminating MAS from active sJIA, with a sensitivity of 0.85, a specificity of 0.95 and a kappa value of 0.80. The good performance of the MS score was confirmed in the validation sample. Conclusion The MS score is a powerful and feasible tool that may assist practitioners in making a timely diagnosis of MAS in patients with sJIA.
AB - Objective To develop and validate a diagnostic score that aids in identifying macrophage activation syndrome (MAS) in patients with systemic juvenile idiopathic arthritis (sJIA). Methods The clinical and laboratory features of 362 patients with sJIA-associated MAS and 404 patients with active sJIA without evidence of MAS were collected in a multinational collaborative project. Eighty percent of the study population was used to develop the score and the remaining 20% constituted the validation sample. A Bayesian Model Averaging approach was used to assess the role of each clinical and laboratory variables in the diagnosis of MAS and to obtain the coefficients of selected variables. The final score, named MAS/sJIA (MS) score, resulted from the linear combination of these coefficients multiplied by the values of each variable. The cut-off that best discriminated MAS from active sJIA was calculated by means of receiver operating characteristic (ROC) curve analysis. Score performance was evaluated in both developmental and validation samples. Results The MS score ranges from-8.4 to 41.8 and comprises seven variables: central nervous system dysfunction, haemorrhagic manifestations, active arthritis, platelet count, fibrinogen, lactate dehydrogenase and ferritin. A cut-off value ≥-2.1 revealed the best performance in discriminating MAS from active sJIA, with a sensitivity of 0.85, a specificity of 0.95 and a kappa value of 0.80. The good performance of the MS score was confirmed in the validation sample. Conclusion The MS score is a powerful and feasible tool that may assist practitioners in making a timely diagnosis of MAS in patients with sJIA.
KW - diagnostic score
KW - hemophagocytic syndrome
KW - macrophage activation syndrome
KW - still's disease
KW - systemic juvenile idiopathic arthritis
UR - http://www.scopus.com/inward/record.url?scp=85070296112&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85070296112&partnerID=8YFLogxK
U2 - 10.1136/annrheumdis-2019-215211
DO - 10.1136/annrheumdis-2019-215211
M3 - Article
C2 - 31296501
AN - SCOPUS:85070296112
VL - 78
SP - 1357
EP - 1362
JO - Annals of the Rheumatic Diseases
JF - Annals of the Rheumatic Diseases
SN - 0003-4967
IS - 10
ER -