Development and Initial Validation of the ONCOREUM Score to Differentiate Childhood Cancer with Arthropathy from Juvenile Idiopathic Arthritis.

OBJECTIVE: To develop and validate a weighted score, the ONCOREUM score, that aids physicians in differentiation of cancer with arthropathy from juvenile idiopathic arthritis (JIA). STUDY DESIGN: Data were extracted from the ONCOREUM Study, a multicenter, cross-sectional investigation aimed at comparing children with cancer and arthropathy to children with JIA. Three statistical approaches were applied to develop the ONCOREUM score and assess the role of each variable in the diagnosis of cancer with arthropathy, including 2 approaches based on multivariable stepwise selection (models 1 and 2) and 1 approach on a Bayesian model averaging method (model 3). The ß coefficients estimated in the models were used to assign score points. Considering that not missing a child with cancer is a mandatory clinical objective, discriminating performance was assessed by fixing sensitivity at 100%. Score performance was evaluated in both developmental and validation samples (representing 80% and 20% of the study population, respectively). RESULTS: Patients with cancer and arthropathy (49 with solid tumors and 46 with hematologic malignancies without peripheral blasts) and 677 patients with JIA were included. The highest area under the receiver operating characteristic (ROC) curve (AUC) in the validation data set was yielded by model 1, which was selected to constitute the ONCOREUM score. The score ranged from -18 to 21.8, and the optimal cutoff obtained through ROC analysis was -6. The sensitivity, specificity, and AUC of the cutoff in the validation sample were 100%, 70%, and 0.85, respectively. CONCLUSIONS: The ONCOREUM score is a powerful and easily applicable tool that may facilitate early differentiation of malignancies with articular complaints from JIA.

Discrimination between incomplete and atypical Kawasaki syndrome versus other febrile diseases in childhood: results from an international registry-based study.

OBJECTIVES: Kawasaki syndrome (KS) is an acute systemic vasculitis of unknown origin predominantly affecting young children. Early diagnosis is crucial to prevent cardiac complications. However, the differential diagnosis of patients with the incomplete or atypical form of the disease poses a heavy challenge for the paediatrician. Our aim was to evaluate the prevalence of incomplete and atypical cases among children with KS and to identify clinical and laboratory variables that may help differentiate incomplete and atypical KS from other febrile diseases at this age. METHODS: We established an international registry to recruit patients with KS, including those with incomplete and atypical forms. The control group included age-matched febrile children admitted to the hospital with a variety of diseases mimicking KS. The aim was to define clinical or laboratory clues to help in the discrimination of incomplete and atypical KS patients from others. RESULTS: Two hundred and twenty-eight patients with incomplete KS (78%) and atypical KS (22%) were compared to 71 children with other febrile diseases. Patients with incomplete and atypical KS presented a statistically significant higher frequency of mucosal changes, conjunctivitis, extremity abnormalities and perineal desquamation compared to the group of other febrile diseases. In addition, C-reactive protein and platelet counts were significantly higher in incomplete and atypical KS compared to the other group. CONCLUSIONS: This is the largest series of incomplete and atypical KS patients of non East-Asian ancestry: we suggest that in patients with the aforementioned clinical features and laboratory evidence of systemic inflammation in terms of increased C-reactive protein and platelet counts an echocardiogram should be performed and diagnosis of KS considered.

Preliminary diagnostic guidelines for macrophage activation syndrome complicating systemic juvenile idiopathic arthritis.

OBJECTIVE: To develop diagnostic guidelines for macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (S-JIA). STUDY DESIGN: We followed the classification criteria approach that is based on the comparison of patients with the index disease with patients with a "confusable" disease. The former group included 74 patients with S-JIA-associated MAS reported in the literature or seen by the authors; the latter group included 37 patients with S-JIA who had 51 instances of "high disease activity" seen by the authors. The relative power of clinical, laboratory, and histopathologic variables in discriminating patients with MAS from patients with high disease activity was evaluated by calculating the sensitivity rate, specificity rate, area under the receiver operating characteristic curve, and diagnostic odds ratio (DOR). The combinations of variables that led to best separation between patients and control subjects were identified through "the number of criteria present" method. RESULTS: The strongest clinical discriminators were hemorrhages (DOR = 67) and central nervous system dysfunction (DOR = 63); the strongest laboratory discriminators were decreased platelet count (DOR = 1092), increased aspartate aminotransferase (DOR = 247), leukopenia (DOR = 70), and hypofibrinogenemia (DOR = 165). The best separation between patients and control subjects occurred when any 2 or more laboratory criteria (DOR = 1309) were simultaneously present; the second best performance was provided by the presence of any 2, 3, or more clinical and/or laboratory criteria (DOR = 765 and 743, respectively). CONCLUSION: We identified preliminary diagnostic guidelines for MAS complicating S-JIA. These guidelines deserve prospective validation.