Inflammatory Biomarkers Can Differentiate Acute Lymphoblastic Leukemia with Arthropathy from Juvenile Idiopathic Arthritis Better Than Standard Blood Tests.

OBJECTIVE: To evaluate the predictive value of biomarkers of inflammation like phagocyte-related S100 proteins and a panel of inflammatory cytokines in order to differentiate the child with acute lymphoblastic leukemia (ALL) from juvenile idiopathic arthritis (JIA). STUDY DESIGN: In this cross-sectional study, we measured S100A9, S100A12, and 14 cytokines in serum from children with ALL (n = 150, including 27 with arthropathy) and JIA (n = 236). We constructed predictive models computing areas under the curve (AUC) as well as predicted probabilities in order to differentiate ALL from JIA. Logistic regression was used for predictions of ALL risk, considering the markers as the respective exposures. We performed internal validation using repeated 10-fold cross-validation and recalibration, adjusted for age. RESULTS: In ALL, the levels of S100A9, S100A12, interleukin (IL)-1 beta, IL-4, IL-13, IL-17, matrix metalloproteinase-3, and myeloperoxidase were low compared with JIA (P < .001). IL-13 had an AUC of 100% (95% CI 100%-100%) due to no overlap between the serum levels in the 2 groups. Further, IL-4 and S100A9 had high predictive performance with AUCs of 99% (95% CI 97%-100%) and 98% (95% CI 94%-99%), respectively, exceeding both hemoglobin, platelets, C-reactive protein, and erythrocyte sedimentation rate. CONCLUSIONS: The biomarkers S100A9, IL-4, and IL-13 might be valuable markers to differentiate ALL from JIA.

Musculoskeletal Diagnoses before Cancer in Children: A Danish Registry-Based Cohort Study.

OBJECTIVE: To identify the prevalence of musculoskeletal diagnoses recorded 6 months before the diagnosis of cancer and to evaluate whether preceding musculoskeletal diagnoses affected survival. STUDY DESIGN: We performed a nationwide registry-based cohort study including all children under 15 years of age diagnosed with cancer in Denmark over a 23-year period (1996-2018). The Danish National Patient Registry was used to identify musculoskeletal diagnoses and associated dates recorded within 6 months preceding the diagnosis of cancer. We compared the characteristics of children with and without a prior musculoskeletal diagnoses using prevalence ratios and 95% CI and diagnostic interval as median with IQR. We compared survival using Kaplan-Meier and Cox proportional hazards regression analysis adjusting for age, sex, and presence of metastasis at diagnosis. RESULTS: Of 3895 children with all types of cancer, 264 (7%) had a total of 451 hospital visits with musculoskeletal diagnosis within 6 months preceding the diagnosis of cancer; however, survival was not affected. The overall median diagnostic interval from first musculoskeletal diagnosis (within 6 months before cancer diagnosis) to cancer diagnosis was 15 days (IQR, 7-47 days). A diagnosis of juvenile idiopathic arthritis, unspecified arthritis, and arthropathy each accounted for 5% of the contacts, primarily in children with acute lymphoblastic leukemia, bone sarcomas, or neuroblastomas. CONCLUSIONS: A preliminary musculoskeletal diagnosis occurred in 7% of children with cancer, but did not affect the overall survival.

Mitochondrial 12S ribosomal RNA A1555G mutation associated with cardiomyopathy and hearing loss following high-dose chemotherapy and repeated aminoglycoside exposure.

A 19-month-old girl with the A1555G mitochondrial mutation in the 12S ribosomal RNA gene and acute myelogenous leukemia developed dilated cardiomyopathy and bilateral sensorineural hearing loss before undergoing allogeneic stem cell transplantation. She had received gentamicin during episodes of febrile neutropenia. Testing for the A1555G mutation is recommended in patients frequently treated with aminoglycosides.