Iatrogenic Flexion-Related Classic Metaphyseal Lesion of the Distal Tibia: Three Cases.

BACKGROUND: Classic metaphyseal lesions (CMLs) should raise concern for nonaccidental trauma. However, iatrogenic causes for CMLs have increasingly been described and warrant close consideration. Increasing the clinical understanding of CML mechanics and their relation to often routine medical procedures will enhance provider awareness and expand the differential diagnosis when these otherwise highly concerning injuries are identified. CASE REPORTS: We describe three clinical cases where suspected iatrogenic dorsiflexion or plantar flexion resulted in an isolated distal tibia CML. Respectively, we present heel-stick testing and i.v. line placement as clinical correlates of these two mechanisms. Although prior reports have aimed to describe iatrogenic CML etiologies, they have not focused on dorsiflexion or plantar flexion as predominant mechanisms of injury. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians are critical to the surveillance and identification of nonaccidental trauma. Given that children oftentimes present to the emergency department with subtle yet concerning signs of maltreatment, an emergency physician must be aware of the potential causes of injury as well as the recommended response. Although avoiding missed cases of abuse and improving the detection of injuries is crucial for child health and well-being, failing to consider or recognize alternative explanations could also have serious implications for a child and their caregivers.

Zinc-finger protein Zpr1 is a bespoke chaperone essential for eEF1A biogenesis.

The conserved regulon of heat shock factor 1 in budding yeast contains chaperones for general protein folding as well as zinc-finger protein Zpr1, whose essential role in archaea and eukaryotes remains unknown. Here, we show that Zpr1 depletion causes acute proteotoxicity driven by biosynthesis of misfolded eukaryotic translation elongation factor 1A (eEF1A). Prolonged Zpr1 depletion leads to eEF1A insufficiency, thereby inducing the integrated stress response and inhibiting protein synthesis. Strikingly, we show by using two distinct biochemical reconstitution approaches that Zpr1 enables eEF1A to achieve a conformational state resistant to protease digestion. Lastly, we use a ColabFold model of the Zpr1-eEF1A complex to reveal a folding mechanism mediated by the Zpr1's zinc-finger and alpha-helical hairpin structures. Our work uncovers the long-sought-after function of Zpr1 as a bespoke chaperone tailored to the biogenesis of one of the most abundant proteins in the cell.

Burkitt Lymphoma After Cardiac Transplantation: Therapeutic Considerations.

Postsolid organ transplant Burkitt lymphoma (PSOT-BL) is rare but more aggressive than other post-transplant lymphoproliferative disorders (PTLD). Little is known about optimal treatment and outcome of postcardiac transplant Burkitt lymphoma (BL). We report an 8-year-old boy with a history of heart transplant who developed Epstein-Barr virus positive, late-onset PSOT-BL. He was successfully treated with BL specific chemoimmunotherapy and cessation of baseline immunosuppression. In this pediatric case of PSOT-BL, the use of standard intensive pediatric based chemoimmunotherapy regimen without modifications was feasible, well tolerated and resulted in complete remission. Long-term toxicities need further study.

Economics at the FCC 2019-2020: Spectrum Policy, Universal Service, Inmate Calling Services, and Telehealth.

The U.S. Federal Communications Commission is responsible for regulation in the communications marketplace and for management of the nation's non-federal radio frequency spectrum. During the past year, FCC economists helped develop efficient mechanisms for making available more flexible-use spectrum for the deployment of advanced broadband technologies; developed two new universal service funding mechanisms that aim to close the digital broadband divide; and, through careful analysis of firm cost data, contributed to a renewed effort by the Commission to develop price caps for interstate calls on prison inmate calling services. FCC economists also contributed to the Commission's extensive response to COVID-19.

The contribution of ketone bodies to glycolytic inhibition for the treatment of adult and pediatric glioblastoma.

PURPOSE: Glioblastoma (GBM) remains one of the most lethal primary brain tumors in children and adults. Targeting tumor metabolism has emerged as a promising-targeted therapeutic strategy for GBM and characteristically resistant GBM stem-like cells (GSCs). METHODS: Gene expression data was obtained from the online patient-histology database, GlioVis. GSC mitochondria morphology was examined by TEM. Cell viability and effect on GSC self-renewal was determined via MTS assay and neurosphere assay, respectively. Proteins were evaluated by Western Blot. RESULTS: Enzymes necessary for ketone catabolism (BDH1, OXCT1 and ACAT1) are significantly downregulated in adult and pediatric GBM. GSC mitochondrial ultrastructure suggested defects in oxidative phosphorylation. Treatment of both GBM and GSC cell lines resulted in dose-dependent decreases in viability in response to glycolytic inhibitor 2-deoxy-D-glucose (2-DG), and ketone body Acetoacetate (AA), but not ß-hydroxybutyrate (ßHB). AA induced apoptosis was confirmed by western blot analysis, indicating robust caspase activation and PARP cleavage. AA reduced neurosphere formation at concentrations as low as 1 mM. Combined treatment of low dose 2-DG (50 µM) with AA resulted in more cell death than either treatment alone. The effect was greater than additive at low concentrations of AA, reducing viability approximately 50% at 1 mM AA. AA was found to directly upregulate mitochondrial uncoupling protein 2 (UCP2), which may explain this potential drug synergism via multi-faceted inhibition of the glycolytic pathway. CONCLUSION: Targeting the metabolic pathway of GBM via glycolytic inhibition in conjunction with ketogenic diet or exogenous ketone body supplementation warrants further investigation as a promising adjunctive treatment to conventional therapy.

Targeting Glioblastoma Stem Cells with 2-Deoxy-D-Glucose (2-DG) Potentiates Radiation-Induced Unfolded Protein Response (UPR).

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults, and despite optimized treatment options, median survival remains dismal. Contemporary evidence suggests disease recurrence results from expansion of a robustly radioresistant subset of GBM progenitor cells, termed GBM stem cells (GSCs). In this study, we utilized transmission electron microscopy to uncover ultrastructural effects on patient-derived GSC lines exposed to supratherapeutic radiotherapy levels. Elevated autophagosome formation and increased endoplasmic reticulum (ER) internal diameter, a surrogate for ER stress and activation of unfolded protein response (UPR), was uncovered. These observations were confirmed via protein expression through Western blot. Upon interrogating genomic data from an open-access GBM patient database, overexpression of UPR-related chaperone protein genes was inversely correlated with patient survival. This indicated controlled UPR may play a role in promoting radioresistance. To determine if potentiating UPR further can induce apoptosis, we exposed GSCs to radiation with an ER stress-inducing drug, 2-deoxy-D-glucose (2-DG), and found dose-dependent decreases in viability and increased apoptotic marker expression. Taken together, our results indicate GSC radioresistance is, in part, achieved by overexpression and overactivation of ER stress-related pathways, and this effect can be overcome via potentiation of UPR, leading to loss of GSC viability.

Degradation of AMPK-α1 sensitizes BRAF inhibitor-resistant melanoma cells to arginine deprivation.

Melanomas harboring BRAF mutation (V600E) are known to recur frequently following treatment with BRAF inhibitors (BRAFi) despite a high initial response rate. Our previous study has uncovered that BRAFi-resistant melanoma (BR) cells are vulnerable to arginine deprivation. It has been reported that naïve melanoma cells undergo autophagy and re-express argininosuccinate synthetase 1 (ASS1) to enable them to synthesize arginine for survival when encountering arginine deprivation. Abolishing these two factors in BR cells confers sensitivity to arginine deprivation. In this report, we further demonstrated that downregulation of AMPK-α1 in BR cells is a major factor contributing to impairment of autophagy as evidenced by decreased autophagosome formation. These BR cells also showed a metabolic shift from glucose to arginine dependence, which was supported by decreased expressions of GLUT1 (glucose transporter) and hexokinase II (HKII) coupled with less glucose uptake but high levels of arginine transporter CAT-2 expression. Furthermore, silencing CAT-2 expression also distinctly attenuated BR cell proliferation. Notably, when naïve melanoma cells became BR cells by long-term exposure to BRAFi, a stepwise degradation of AMPK-α1 was initiated via ubiquitin-proteasome system (UPS). We discovered that a novel E3 ligase, RING finger 44 (RNF44), is responsible for promoting AMPK-α1 degradation in BR cells. RNF44 expression in BR cells was upregulated by transcription factor CREB triggered by hyperactivation of ERK/AKT. High levels of RNF44 corresponding to low levels of AMPK-α1 appeared in BR xenografts and melanoma tumor samples from BR and BRAFi/MEK inhibitor (MEKi)-resistant (BMR) melanoma patients. Similar to BR cells, BMR cells were also sensitive to arginine deprivation. Our study provides a novel insight into the mechanism whereby BRAFi or BRAFi/MEKi resistance drives proteasomal degradation of AMPK-α1 and consequently regulates autophagy and metabolic reprogramming in melanoma cells.

Exploiting ROS and metabolic differences to kill cisplatin resistant lung cancer.

Cisplatin resistance remains a major problem in the treatment of lung cancer. We have discovered that cisplatin resistant (CR) lung cancer cells, regardless of the signaling pathway status, share the common parameter which is an increase in reactive oxygen species (ROS) and undergo metabolic reprogramming. CR cells were no longer addicted to the glycolytic pathway, but rather relied on oxidative metabolism. They took up twice as much glutamine and were highly sensitive to glutamine deprivation. Glutamine is hydrolyzed to glutamate for glutathione synthesis, an essential factor to abrogate high ROS via xCT antiporter. Thus, blocking glutamate flux using riluzole (an amyotropic lateral sclerosis approved drug) can selectively kill CR cells in vitro and in vivo. However, we discovered here that glutathione suppression is not the primary pathway in eradicating the CR cells. Riluzole can lead to further decrease in NAD+ (nicotinamide adenine dinucleotide) and lactate dehydrogenase-A (LDHA) expressions which in turn further heightened oxidative stress in CR cells. LDHA knocked-down cells became hypersensitive to riluzole treatments and possessed increased levels of ROS. Addition of NAD+ re-stabilized LDHA and reversed riluzole induced cell death. Thus far, no drugs are available which could overcome cisplatin resistance or kill cisplatin resistant cells. CR cells possess high levels of ROS and undergo metabolic reprogramming. These metabolic adaptations can be exploited and targeted by riluzole. Riluzole may serve as a dual-targeting agent by suppression LDHA and blocking xCT antiporter. Repurposing of riluzole should be considered for future treatment of cisplatin resistant lung cancer patients.

Pediatric Chest CT Diagnostic Reference Ranges: Development and Application.

Purpose To determine diagnostic reference ranges on the basis of the size of a pediatric patient's chest and to develop a method to estimate computed tomographic (CT) scanner-specific mean size-specific dose estimates (SSDEs) as a function of patient size and the radiation output of each CT scanner at a site. Materials and Methods The institutional review boards of each center approved this retrospective, HIPAA-compliant, multicenter study; informed consent was waived. CT dose indexes (SSDE, volume CT dose index, and dose length product) of 518 pediatric patients (mean age, 9.6 years; male patients, 277 [53%]) who underwent CT between July 1, 2012, and June 30, 2013, according to the guidelines of the Quality Improvement Registry in CT Scans in Children were retrieved from a national dose data registry. Diagnostic reference ranges were developed after analysis of image quality of a subset of 111 CT examinations to validate image quality at the lower bound. Pediatric dose reduction factors were calculated on the basis of SSDEs for pediatric patients divided by SSDEs for adult patients. Results Diagnostic reference ranges (SSDEs) were 1.8-3.9, 2.2-4.5, 2.7-5.1, 3.6-6.6, and 5.5-8.4 mGy for effective diameter ranges of less than 15 cm, 15-19 cm, 20-24 cm, 25-29 cm, and greater than or equal to 30 cm, respectively. The fractions of adult doses (pediatric dose reduction factors) used within the consortium for patients with lateral dimensions of 8, 11, 14, 17, 20, 23, 26, 29, 32, 35, and 38 cm were 0.29, 0.33, 0.38, 0.44, 0.50, 0.58, 0.66, 0.76, 0.87, 1.0, and 1.15, respectively. Conclusion Diagnostic reference ranges developed in this study provided target ranges of pediatric dose indexes on the basis of patient size, while the pediatric dose reduction factors of this study allow calculation of unique reference dose indexes on the basis of patient size for each of a site's CT scanners. © RSNA, 2017 Online supplemental material is available for this article.

Novel "Superspreader" Bacteriophages Promote Horizontal Gene Transfer by Transformation.

Bacteriophages infect an estimated 1023 to 1025 bacterial cells each second, many of which carry physiologically relevant plasmids (e.g., those encoding antibiotic resistance). However, even though phage-plasmid interactions occur on a massive scale and have potentially significant evolutionary, ecological, and biomedical implications, plasmid fate upon phage infection and lysis has not been investigated to date. Here we show that a subset of the natural lytic phage population, which we dub "superspreaders," releases substantial amounts of intact, transformable plasmid DNA upon lysis, thereby promoting horizontal gene transfer by transformation. Two novel Escherichia coli phage superspreaders, SUSP1 and SUSP2, liberated four evolutionarily distinct plasmids with equal efficiency, including two close relatives of prominent antibiotic resistance vectors in natural environments. SUSP2 also mediated the extensive lateral transfer of antibiotic resistance in unbiased communities of soil bacteria from Maryland and Wyoming. Furthermore, the addition of SUSP2 to cocultures of kanamycin-resistant E. coli and kanamycin-sensitive Bacillus sp. bacteria resulted in roughly 1,000-fold more kanamycin-resistant Bacillus sp. bacteria than arose in phage-free controls. Unlike many other lytic phages, neither SUSP1 nor SUSP2 encodes homologs to known hydrolytic endonucleases, suggesting a simple potential mechanism underlying the superspreading phenotype. Consistent with this model, the deletion of endonuclease IV and the nucleoid-disrupting protein ndd from coliphage T4, a phage known to extensively degrade chromosomal DNA, significantly increased its ability to promote plasmid transformation. Taken together, our results suggest that phage superspreaders may play key roles in microbial evolution and ecology but should be avoided in phage therapy and other medical applications. IMPORTANCE: Bacteriophages (phages), viruses that infect bacteria, are the planet's most numerous biological entities and kill vast numbers of bacteria in natural environments. Many of these bacteria carry plasmids, extrachromosomal DNA elements that frequently encode antibiotic resistance. However, it is largely unknown whether plasmids are destroyed during phage infection or released intact upon phage lysis, whereupon their encoded resistance could be acquired and manifested by other bacteria (transformation). Because phages are being developed to combat antibiotic-resistant bacteria and because transformation is a principal form of horizontal gene transfer, this question has important implications for biomedicine and microbial evolution alike. Here we report the isolation and characterization of two novel Escherichia coli phages, dubbed "superspreaders," that promote extensive plasmid transformation and efficiently disperse antibiotic resistance genes. Our work suggests that phage superspreaders are not suitable for use in medicine but may help drive bacterial evolution in natural environments.

Cryptic Amyloidogenic Elements in the 3' UTRs of Neurofilament Genes Trigger Axonal Neuropathy.

Abnormal protein aggregation is observed in an expanding number of neurodegenerative diseases. Here, we describe a mechanism for intracellular toxic protein aggregation induced by an unusual mutation event in families affected by axonal neuropathy. These families carry distinct frameshift variants in NEFH (neurofilament heavy), leading to a loss of the terminating codon and translation of the 3' UTR into an extra 40 amino acids. In silico aggregation prediction suggested the terminal 20 residues of the altered NEFH to be amyloidogenic, which we confirmed experimentally by serial deletion analysis. The presence of this amyloidogenic motif fused to NEFH caused prominent and toxic protein aggregates in transfected cells and disrupted motor neurons in zebrafish. We identified a similar aggregation-inducing mechanism in NEFL (neurofilament light) and FUS (fused in sarcoma), in which mutations are known to cause aggregation in Charcot-Marie-Tooth disease and amyotrophic lateral sclerosis, respectively. In summary, we present a protein-aggregation-triggering mechanism that should be taken into consideration during the evaluation of stop-loss variants.

BRAF inhibitor resistance enhances vulnerability to arginine deprivation in melanoma.

BRAF inhibitor (BRAFi) has been used for treatment of melanomas harboring V600E mutation. Despite a high initial response rate, resistance to BRAFi is inevitable. Here, we demonstrate that BRAFi-resistant (BR) melanomas are susceptible to arginine deprivation due to inability to initiate re-expression of argininosuccinate synthetase (ASS1, a key enzyme for arginine synthesis) as well as ineffective autophagy. Autophagy and ASS1 re-expression are known to protect melanoma cells from cell death upon arginine deprivation. When melanoma cells become BR cells by long-term in vitro incubation with BRAFi, c-Myc-mediated ASS1 re-expression and the levels of autophagy-associated proteins (AMPK-α1 and Atg5) are attenuated. Furthermore, our study uncovers that downregulation of deubiquitinase USP28 which results in more active c-Myc degradation via ubiquitin-proteasome machinery is the primary mechanism for inability to re-express ASS1 upon arginine deprivation in BR cells. Overexpression of USP28 in BR cells enhances c-Myc expression and hence increases ASS1 transcription upon arginine deprivation, and consequently leads to cell survival. On the other hand, overexpression of Atg5 or AMPK-α1 in BR cells can redirect arginine deprivation-induced apoptosis toward autophagy. The xenograft models also confirm that BR tumors possess lower expression of ASS1 and are hypersensitive to arginine deprivation. These biochemical changes in BRAFi resistance which make them vulnerable to arginine deprivation can be exploited for the future treatment of BR melanoma patients.

Determinants of Private Long-Term Care Insurance Purchase in Response to the Partnership Program.

OBJECTIVE: To assess three possible determinants of individuals' response in their private insurance purchases to the availability of the Partnership for Long-Term Care (PLTC) insurance program: bequest motives, financial literacy, and program awareness. DATA SOURCES: The health and retirement study (HRS) merged with data on states' implementation of the PLTC program. STUDY DESIGN: Individual-level decision on private long-term care insurance is regressed on whether the PLTC program is being implemented for a given state-year, asset dummies, policy determinant variable, two-way and three-way interactions of these variables, and other controls, using fixed effects panel regression. DATA EXTRACTION METHODS: Analysis used a sample between 50 and 69 years of age from 2002 to 2010, resulting in 12,695 unique individuals with a total of 39,151 observations. PRINCIPAL FINDINGS: We find mild evidence that intent to bequest influences individual purchase of insurance. We also find that program awareness is necessary for response, while financial literacy notably increases responsiveness. CONCLUSIONS: Increasing response to the PLTC program among the middle class (the stated target group) requires increased efforts to create awareness of the program's existence and increased education about the program's benefits, and more generally, about long-term care risks and needs.

Cervical spine imaging in hospitalized children with traumatic brain injury.

OBJECTIVES: The purposes of this study, in children with traumatic brain injury (TBI), to describe cervical spine imaging practice, to assess for recent changes in imaging practice, and to determine whether cervical spine computed tomography (CT) is being used in children at low risk for cervical spine injury. METHODS: The setting was children's hospitals participating in the Pediatric Health Information System database, from January 2001 to June 2011. Participants were children (younger than 18 y) with TBI who were evaluated in the emergency department, admitted to the hospital, and received a head CT scan on the day of admission. The primary outcome measures were cervical spine imaging studies. This study was exempted from institutional review board assessment. RESULTS: A total of 30,112 children met study criteria. Overall, 52% (15,687/30,112) received cervical spine imaging. The use of cervical spine radiographs alone decreased between 2001 (47%) and 2011 (23%), with an annual decrease of 2.2% (95% confidence interval [CI], 1.1%-3.3%), and was largely replaced by an increased use of CT, with or without radiographs (8.6% in 2001 and 19.5% in 2011, with an annual increase of 0.9%; 95% CI, 0.1%-1.8%). A total of 2545 children received cervical spine CT despite being discharged alive from the hospital in less than 72 hours, and 1655 of those had a low-risk mechanism of injury. CONCLUSIONS: The adoption of CT clearance of the cervical spine in adults seems to have influenced the care of children with TBI, despite concerns about radiation exposure.

Sensitivity of the limited view follow-up skeletal survey.

BACKGROUND AND OBJECTIVE: Reducing radiation exposure to minimize risk has been emphasized in recent years. In child abuse, the risk of missing occult injuries is often believed to outweigh radiation risk associated with skeletal surveys. Our hypothesis was that there would be no clinically significant difference in results from a limited view, follow-up skeletal survey (SS2) protocol, which omits spine and pelvis views unless these views have findings on the initial skeletal survey (SS1), compared with a traditional SS2 protocol for radiographic evaluation of suspected physical abuse. METHODS: This study was a retrospective record review involving 5 child protection teams. Consultations for suspected physical abuse were reviewed to identify subjects <24 months of age who had an SS1 and a traditional SS2. The results of these studies were compared to identify subjects in which newly identified spine and pelvis fractures (fractures seen only on SS2 and not on SS1) would have been missed by using a limited view SS2 protocol. RESULTS: We identified 534 study subjects. Five subjects had newly identified spine fractures, and no subjects had newly identified pelvis fractures on traditional SS2 studies. Only 1 subject with a newly identified spine fracture would have been missed with the limited view SS2 protocol used in this study (0.2% [95% confidence interval: <0.005-1.0]). None of the newly identified fractures changed the abuse-related diagnosis. CONCLUSIONS: We found no clinically significant difference in the results of a limited view SS2 protocol versus a traditional SS2 protocol for radiographic evaluation of suspected abuse.

The impact of the partnership long-term care insurance program on private coverage.

We examine the impact of U.S. states' adoption of the partnership long-term care (LTC) insurance program on households' purchases of private coverage. Targeting middle-class households, this program increases the benefits of privately insuring via a higher asset threshold for Medicaid eligibility for LTC coverage. We find that the program generates few new purchases of LTC insurance, and that those it generates are almost entirely by wealthy individuals.

The role of focused abdominal sonography for trauma (FAST) in pediatric trauma evaluation.

PURPOSE: With increasing concerns about radiation exposure, we questioned whether a structured program of FAST might decrease CT use. METHODS: All pediatric trauma surgeons in our level 1 pediatric trauma center underwent formal FAST training. Children with potential abdominal trauma and no prior imaging were prospectively evaluated from 10/2/09 to 7/31/11. After physical exam and FAST, the surgeon declared whether the CT could be eliminated. RESULTS: Of 536 children who arrived without imaging, 183 had potential abdominal trauma. FAST was performed in 128 cases and recorded completely in 88. In 48% (42/88) the surgeon would have elected to cancel the CT based on the FAST and physical exam. One of the 42 cases had a positive FAST and required emergent laparotomy; the others were negative. The sensitivity of FAST for injuries requiring operation or blood transfusion was 87.5%. The sensitivity, specificity, PPV, and NPV in detecting pathologic free fluid were 50%, 85%, 53.8%, and 87.9%. CONCLUSIONS: True positive FAST exams are uncommon and would rarely direct management. While the negative FAST would have potentially reduced CT use due to practitioner reassurance, this reassurance may be unwarranted given the test's sensitivity.

Diagnostic reference ranges for pediatric abdominal CT.

PURPOSE: To develop diagnostic reference ranges (DRRs) and a method for an individual practice to calculate site-specific reference doses for computed tomographic (CT) scans of the abdomen or abdomen and pelvis in children on the basis of body width (BW). MATERIALS AND METHODS: This HIPAA-compliant multicenter retrospective study was approved by institutional review boards of participating institutions; informed consent was waived. In 939 pediatric patients, CT doses were reviewed in 499 (53%) male and 440 (47%) female patients (mean age, 10 years). Doses were from 954 scans obtained from September 1 to December 1, 2009, through Quality Improvement Registry for CT Scans in Children within the National Radiology Data Registry, American College of Radiology. Size-specific dose estimate (SSDE), a dose estimate based on BW, CT dose index, dose-length product, and effective dose were analyzed. BW measurement was obtained with electronic calipers from the axial image at the splenic vein level after completion of the CT scan. An adult-sized patient was defined as a patient with BW of 34 cm. An appropriate dose range for each DRR was developed by reviewing image quality on a subset of CT scans through comparison with a five-point visual reference scale with increments of added simulated quantum mottle and by determining DRR to establish lower and upper bounds for each range. RESULTS: For 954 scans, DRRs (SSDEs) were 5.8-12.0, 7.3-12.2, 7.6-13.4, 9.8-16.4, and 13.1-19.0 mGy for BWs less than 15, 15-19, 20-24, 25-29, and 30 cm or greater, respectively. The fractions of adult doses, adult SSDEs, used within the consortium for patients with BWs of 10, 14, 18, 22, 26, and 30 cm were 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9, respectively. CONCLUSION: The concept of DRRs addresses the balance between the patient's risk (radiation dose) and benefit (diagnostic image quality). Calculation of reference doses as a function of BW for an individual practice provides a tool to help develop site-specific CT protocols that help manage pediatric patient radiation doses.

ACR Appropriateness Criteria(®) on suspected physical abuse-child.

The appropriate imaging for pediatric patients being evaluated for suspected physical abuse depends on the age of the child, the presence of neurologic signs and symptoms, evidence of thoracic or abdominopelvic injuries, and whether the injuries are discrepant with the clinical history. The clinical presentations reviewed consider these factors and provide evidence-based consensus recommendations by the ACR Appropriateness Criteria(®) Expert Panel on Pediatric Imaging.

ACR Appropriateness Criteria on developmental dysplasia of the hip--child.

Developmental dysplasia of the hip (DDH) affects 1.5 of every 1,000 caucasian Americans and less frequently affects African Americans. Developmental dysplasia of the hip comprises a spectrum of abnormalities, ranging from laxity of the joint and mild subluxation to fixed dislocation. Early diagnosis of DDH usually leads to low-risk treatment with a harness. Late diagnosis of DDH in children may lead to increased surgical intervention and complications. Late diagnosis of DDH in adults can result in debilitating end-stage degenerative hip joint disease. Screening decreases the incidence of late diagnosis of DDH. Clinical evaluation for DDH should be performed periodically at each well-baby visit until the age of 12 months. There is no consensus on imaging screening for DDH. Consideration for screening with ultrasound is balanced between the benefits of early detection of DDH and the increased treatment and cost factors. In addition, randomized trials evaluating primary ultrasound screening did not find significant decrease in late diagnosis of DDH. In the United States, hip ultrasound is selectively performed in infants with risk factors, such as family history of DDH, breech presentation, and inconclusive findings on physical examination. Ultrasound for DDH should be performed after 2 weeks of age because laxity is common after birth and often resolves itself. A pelvic radiograph can optimally be performed after the age of 4 months, when most infants will have ossification centers of the femoral heads.