Diagnostic accuracy of ultrasound for upper extremity fractures in children: A systematic review and meta-analysis.

OBJECTIVE: Ultrasound has an excellent diagnostic accuracy for fractures that is reportedly comparable to plain radiographs. We aim to summarize the diagnostic accuracy of ultrasound for upper extremity fractures in children. METHODS: Databases were searched from inception through November 2019 using pre-defined index terms, including "ultrasound," "fractures of upper extremities" and "children". The study is reported using Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA). Meta-analysis of the diagnostic accuracy of ultrasound for fractures was conducted using the random-effects bivariate model. Subgroup analysis of fracture site (elbow vs non-elbow fractures) was also performed. Meta-regression was performed to determine if the site of fracture affected the diagnostic accuracy. RESULTS: Thirty-two studies were identified in the meta-analysis. Ultrasound for fractures of the upper extremities has a sensitivity: 0.95 (95% CI: 0.93-0.97), specificity: 0.95 (95% CI: 0.91-0.98), positive likelihood ratio: 21.1 (95% CI: 10.8-41.5) and negative likelihood ratio: 0.05 (95% CI: 0.03-0.07), with an area under ROC (AUROC) curve of 0.98 (95% CI: 0.97-0.99). Subgroup analysis for elbow fracture showed ultrasound has a sensitivity: 0.95 (95% CI: 0.86-0.98), specificity: 0.87 (95% CI: 0.76-0.94), positive likelihood ratio: 7.3 (95% CI: 3.7-14.4) and negative likelihood ratio: 0.06 (95% CI: 0.02-0.16), with an AUROC of 0.96 (95% CI: 0.94-0.97). Meta-regression suggested the fracture sites would affect diagnostic accuracy of ultrasound (elbow vs non-elbow, p < 0.01). CONCLUSIONS: Current evidence suggests ultrasound has excellent diagnostic accuracy for non-elbow upper extremity fractures in children, serving as an alternative diagnostic modality to plain radiographs.

Accuracy of point-of-care ultrasound and radiology-performed ultrasound for intussusception: A systematic review and meta-analysis.

OBJECTIVE: It is unclear whether point-of-care ultrasound (POCUS) by emergency medicine physicians is as accurate as radiology-performed ultrasound (RADUS). We aim to summarize the diagnostic accuracy of ultrasonography for intussusception and to compare the performance between POCUS and RADUS. METHODS: Databases were searched from inception through February 2018 using pre-defined index terms. Peer-reviewed primary studies that investigated the diagnostic accuracy of ultrasound for intussusception in children were included. The study is reported using Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA). Meta-analysis of the diagnostic accuracy of ultrasound for intussusception was conducted using the random-effects bivariate model. Subgroup analysis (POCUS vs RADUS) was also performed. Meta-regression was utilized to determine if the diagnostic accuracy between POCUS and RADUS was significantly different. RESULTS: Thirty studies (n = 5249) were included in the meta-analysis. Ultrasonography for intussusception has a sensitivity: 0.98 (95% CI: 0.96-0.98), specificity: 0.98 (95% CI: 0.95-0.99), positive likelihood ratio: 43.8 (95% CI: 18.0-106.7) and negative likelihood ratio: 0.03 (95% CI: 0.02-0.04), with an area under ROC (AUROC) curve of 0.99 (95% CI: 0.98-1.00). Meta-regression suggested no significant difference in the diagnostic accuracy for intussusception between POCUS and RADUS (AUROC: 0.95 vs 1.00, p = 0.128). CONCLUSIONS: Current evidence suggested POCUS has a high diagnostic accuracy for intussusception not significantly different from that of RADUS.

Point-of-Care Ultrasound Identification of a Psoas Abscess in a Child Presenting With Hip Pain.

This case-report describes a 4-year-old girl brought to the emergency department for the evaluation of limp and elevated inflammatory markers. The patient's history and physical examination did not reveal a clear source of pathology. Point-of-care ultrasound identified a right-sided psoas abscess that was confirmed with computed tomography scan. This case demonstrates the potential utility of point-of-care ultrasound in the diagnosis and management of patients presenting to the emergency department with symptoms concerning for pathology in the hip or lower abdomen.

Synovial fluid findings in children with knee monoarthritis in lyme disease endemic areas.

BACKGROUND: Although Lyme and septic arthritis of the knee may have similar clinical presentations, septic arthritis requires prompt identification and treatment to avoid joint destruction. We sought to determine whether synovial fluid cell counts alone can discriminate between Lyme, septic, and other inflammatory arthritis. METHODS: We conducted a retrospective cohort study of children aged 1 to 18 years with knee monoarthritis who presented to 1 of 2 pediatric emergency departments located in Lyme endemic areas. We included children who had both a synovial fluid culture and an evaluation for Lyme disease. Septic arthritis was defined as a positive synovial fluid culture or synovial fluid pleocytosis (white blood cell [WBC] ≥40,000 cells/µL) with a positive blood culture. Lyme arthritis was defined as positive Lyme serology without a positive bacterial culture. All other children were considered to have other inflammatory arthritis. We compared the synovial fluid counts by arthritis type. RESULTS: We identified 384 children with knee monoarthritis, of whom 19 (5%) had septic arthritis, 257 (67%) had Lyme arthritis and 108 (28%) had other inflammatory arthritis. Children with other inflammatory arthritis had lower synovial WBC and absolute neutrophil count, as well as percent neutrophils, than those with either Lyme or septic arthritis. There were no significant differences in the synovial fluid WBC, absolute neutrophil count, and percent neutrophils for children with Lyme and septic arthritis. CONCLUSIONS: In Lyme endemic areas, synovial fluid results alone do not differentiate septic from Lyme arthritis. Therefore, other clinical or laboratory indicators are needed to direct the care of patients with knee monoarthritis.

Diagnostic accuracy of procalcitonin for bacterial pneumonia in children - a systematic review and meta-analysis.

Objective: The predictive role of procalcitonin for childhood bacterial pneumonia, a leading cause of death, is unclear. We aimed to evaluate the diagnostic accuracy of procalcitonin for childhood bacterial pneumonia.Methods: Major bibliographic databases were searched from inception through September 2019 using pre-defined index terms, including 'procalcitonin,' 'pneumonia' and 'children'. The study is reported according to Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies. Meta-analyses of the diagnostic accuracy and odds ratio of procalcitonin for bacterial pneumonia were conducted along with subgroup analyses for different cut-offs of procalcitonin. The Quality Assessment of Diagnostic Accuracy Studies 2 instrument was used to assess the methodologic quality of eligible studies.Results: Twenty-five studies (with 2,864 patients) showed that procalcitonin for bacterial pneumonia had an overall sensitivity of 0.64 (95% confidence interval: 0.53-0.74), specificity of 0.72 (95% confidence interval: 0.64-0.79), positive likelihood ratio of 2.3 (95% confidence interval: 1.8-3.0) and negative likelihood ratio of 0.50 (95% confidence interval: 0.38-0.66), and Area Under the Receiver Operating Characteristics of 0.74 (95% confidence interval: 0.70-0.78). Using a cut-off of 0.5 ng/ml, Procalcitonin had a sensitivity of 0.68 (95% confidence interval: 0.50-0.82), specificity of 0.60 (95% confidence interval: 0.47-0.72), and Area Under the Receiver Operating Characteristics of 0.68 (95% confidence interval: 0.64-0.72). Using a cut-off of 2 ng/ml, procalcitonin had a sensitivity of 0.59 (95% confidence interval: 0.40-0.76), specificity of 0.71 (95% confidence interval: 0.58-0.81), and AUROC curve of 0.71 (95% confidence interval: 0.67-0.75). Elevated procalcitonin was not associated with increased odds of bacterial pneumonia (odds ratio: 1.36, 95% confidence interval: 0.81-1.92, p = .18). Quality assessment found minimal concerns for bias or applicability.Conclusions: Given the moderate diagnostic accuracy of procalcitonin for bacterial pneumonia, we recommend that procalcitonin be used in conjunction with other findings for management and disposition of children with pneumonia.

Diagnostic Accuracy of Lung Ultrasound Performed by Novice Versus Advanced Sonographers for Pneumonia in Children: A Systematic Review and Meta-analysis.

BACKGROUND: Childhood pneumonia is a leading cause of mortality worldwide. Growing evidence suggests that lung ultrasound (LUS) may be a reliable diagnostic alternative to chest x-ray for childhood pneumonia. However, it is unclear whether sonographer experience affects the diagnostic accuracy of LUS. We summarize the diagnostic accuracy of LUS for pneumonia and compare the performance between novice and advanced sonographers with a systematic review and meta-analysis. METHODS: We searched PubMed and EMBASE from inception to February 2018 for eligible studies that evaluated the utility of LUS in children suspected of having pneumonia against the reference standard of either imaging results alone or a combination of clinical, laboratory, and imaging results. We reported the study using the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies. We used QUADAS-2 to appraise the included studies' methodologic quality. We employed a random-effect bivariate model and a hierarchical summary receiver operating characteristic curve to evaluate LUS's performance characteristics. We conducted subgroup analyses and meta-regression based on level of sonographer training to summarize and compare LUS's diagnostic accuracy for pneumonia between novice (training ≤ 7 days) and advanced sonographers. RESULTS: Twenty-five studies (n = 3,353) were included in the meta-analysis. For diagnosing pneumonia, LUS demonstrated an overall sensitivity of 0.94 (95% confidence interval [CI] = 0.89 to 0.97), specificity of 0.92 (95% CI = 0.78 to 0.98), positive likelihood ratio of 12.40 (95% CI = 4.00 to 38.10), and negative likelihood ratio of 0.07 (95% CI = 0.04 to 0.12), with an area under ROC curve of 0.97 (95% CI = 0.95 to 0.98). Meta-regression revealed a significant difference in the diagnostic accuracy for pneumonia for LUS between novice and advanced sonographers (p < 0.01). CONCLUSION: LUS can accurately diagnose pneumonia in children. However, this test demonstrates operator-dependent variability, with more experienced sonographers having higher diagnostic accuracy. Further work on evidence-based educational methods to train novice sonographers in LUS is required.

Distinguishing Lyme from septic knee monoarthritis in Lyme disease-endemic areas.

OBJECTIVE: Because Lyme and septic arthritis may present similarly, we sought to identify children with knee monoarthritis at low risk for septic arthritis who may not require arthrocentesis. METHODS: We performed a retrospective study of children with knee monoarthritis presenting to 1 of 2 pediatric centers, both located in Lyme disease-endemic areas. Septic arthritis was defined by a positive result on synovial fluid culture or synovial fluid pleocytosis with a positive blood culture result. Lyme arthritis was defined as a positive Lyme serologic result or physician-documented erythema migrans rash. All other children were considered to have other inflammatory arthritis. A clinical prediction model was derived by using recursive partitioning to identify children at low risk for septic arthritis, and the model was then externally validated. RESULTS: We identified 673 patients with knee monoarthritis; 19 (3%) had septic arthritis, 341 (51%) had Lyme arthritis, and 313 (46%) had other inflammatory arthritis. The following predictors of knee septic arthritis were identified: peripheral blood absolute neutrophil count ≥10 × 10(3) cells per mm(3) and an erythrocyte sedimentation rate ≥40 mm/hour. In the validation population, no child with a absolute neutrophil count <10 × 10(3) cells per mm(3) and an erythrocyte sedimentation rate <40 mm/hour had septic arthritis (sensitivity: 6 of 6 [100%], 95% confidence interval [CI]: 54-100; specificity: 87 of 160 [54%], 95% CI: 46-62). Overall, none of the 19 children with septic arthritis were classified as low risk (10%, 95% CI: 0-17). CONCLUSIONS: Laboratory criteria can be used to identify children with knee monoarthritis at low risk for septic arthritis who may not require diagnostic arthrocentesis.

Identification of phosphorylated residues that affect the activity of the mitotic kinase Aurora-A.

The activity of the kinase Aurora-A (Aur-A) peaks during mitosis and depends on phosphorylation by one or more unknown kinases. Mitotic phosphorylation sites were mapped by mass spec sequencing of recombinant Aur-A protein that had been activated by incubation in extracts of metaphase-arrested Xenopus eggs. Three sites were identified: serine 53 (Ser-53), threonine 295 (Thr-295), and serine 349 (Ser-349), which are equivalent to Ser-51, Thr-288, and Ser-342, respectively, in human Aur-A. To ask how phosphorylation of these residues might affect kinase activity, each was mutated to either alanine or aspartic acid, and the recombinant proteins were then tested for their ability to be activated by M phase extract. Mutation of Thr-295, which resides in the activation loop of the kinase, to either alanine or aspartic acid abolished activity. The S349A mutant had slightly reduced activity, indicating that phosphorylation is not required for activity. The S349D mutation completely blocked activation, suggesting that Ser-349 is important for either the structure or regulation of Aur-A. Finally, like human Aur-A, overexpression of Xenopus Aur-A transformed NIH 3T3 cells and led to tumors in nude mice. These results provide further evidence that Xenopus Aur-A is a functional ortholog of human Aur-A and, along with the recently described crystal structure of human Aur-A, should help in future studies of the mechanisms that regulate Aur-A activity during mitotic progression.