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1.
Ecol Evol ; 13(9): e10456, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37664509

RESUMO

Understanding sexual reproduction and recruitment in seagrasses is crucial to their conservation and restoration. Flowering, seed production, seed recruitment, and seedling establishment data for the seagrass Posidonia australis was collected annually between 2013 and 2018 in meadows at six locations around Rottnest Island, Western Australia. Variable annual rates of flowering and seed production were observed among meadows between northern and southern sides of the island and among years. Meadows on the northern shore consistently flowered more intensely and produced more seeds across the years of the survey. Inter-site variation in clonal diversity and size of clones, seed production, wind and surface currents during pollen and seed release, and the large, but variable, impact of seed predation are likely the principal drivers of successful recruitment into established meadows and in colonizing unvegetated sands. The prolific but variable annual reproductive investment increases the probability of low levels of continuous recruitment from seed in this seagrass, despite high rates of abiotic and biotic disturbance at seedling, shoot, and patch scales. This strategy also imparts a level of ecological resilience to this long-lived and persistent species.

2.
Proc Natl Acad Sci U S A ; 120(23): e2220678120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252966

RESUMO

Global change has converted many structurally complex and ecologically and economically valuable coastlines to bare substrate. In the structural habitats that remain, climate-tolerant and opportunistic species are increasing in response to environmental extremes and variability. The shifting of dominant foundation species identity with climate change poses a unique conservation challenge because species vary in their responses to environmental stressors and to management. Here, we combine 35 y of watershed modeling and biogeochemical water quality data with species comprehensive aerial surveys to describe causes and consequences of turnover in seagrass foundation species across 26,000 ha of habitat in the Chesapeake Bay. Repeated marine heatwaves have caused 54% retraction of the formerly dominant eelgrass (Zostera marina) since 1991, allowing 171% expansion of the temperature-tolerant widgeongrass (Ruppia maritima) that has likewise benefited from large-scale nutrient reductions. However, this phase shift in dominant seagrass identity now presents two significant shifts for management: Widgeongrass meadows are not only responsible for rapid, extensive recoveries but also for the largest crashes over the last four decades; and, while adapted to high temperatures, are much more susceptible than eelgrass to nutrient pulses driven by springtime runoff. Thus, by selecting for rapid post-disturbance recolonization but low resistance to punctuated freshwater flow disturbance, climate change could threaten the Chesapeake Bay seagrass' ability to provide consistent fishery habitat and sustain functioning over time. We demonstrate that understanding the dynamics of the next generation of foundation species is a critical management priority, because shifts from relatively stable habitat to high interannual variability can have far-reaching consequences across marine and terrestrial ecosystems.


Assuntos
Alismatales , Zosteraceae , Alismatales/fisiologia , Ecossistema , Mudança Climática , Baías
3.
Proc Natl Acad Sci U S A ; 119(32): e2121425119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914147

RESUMO

Distribution of Earth's biomes is structured by the match between climate and plant traits, which in turn shape associated communities and ecosystem processes and services. However, that climate-trait match can be disrupted by historical events, with lasting ecosystem impacts. As Earth's environment changes faster than at any time in human history, critical questions are whether and how organismal traits and ecosystems can adjust to altered conditions. We quantified the relative importance of current environmental forcing versus evolutionary history in shaping the growth form (stature and biomass) and associated community of eelgrass (Zostera marina), a widespread foundation plant of marine ecosystems along Northern Hemisphere coastlines, which experienced major shifts in distribution and genetic composition during the Pleistocene. We found that eelgrass stature and biomass retain a legacy of the Pleistocene colonization of the Atlantic from the ancestral Pacific range and of more recent within-basin bottlenecks and genetic differentiation. This evolutionary legacy in turn influences the biomass of associated algae and invertebrates that fuel coastal food webs, with effects comparable to or stronger than effects of current environmental forcing. Such historical lags in phenotypic acclimatization may constrain ecosystem adjustments to rapid anthropogenic climate change, thus altering predictions about the future functioning of ecosystems.


Assuntos
Ecossistema , Zosteraceae , Aclimatação , Animais , Evolução Biológica , Biomassa , Cadeia Alimentar , Invertebrados , Zosteraceae/genética
4.
J Environ Manage ; 321: 115901, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35998533

RESUMO

Synthesizing large, complex data sets to inform resource managers towards effective environmental stewardship is a universal challenge. In Chesapeake Bay, a well-studied and intensively monitored estuary in North America, the challenge of synthesizing data on water quality and land use as factors related to a key habitat, submerged aquatic vegetation, was tackled by a team of scientists and resource managers operating at multiple levels of governance (state, federal). The synthesis effort took place over a two-year period (2016-2018), and the results were communicated widely to a) scientists via peer review publications and conference presentations; b) resource managers via web materials and workshop presentations; and c) the public through newspaper articles, radio interviews, and podcasts. The synthesis effort was initiated by resource managers at the United States Environmental Protection Agencys' Chesapeake Bay Program and 16 scientist participants were recruited from a diversity of organizations. Multiple short, immersive workshops were conducted regularly to conceptualize the problem, followed by data analysis and interpretation that supported the preparation of the synthetic products that were communicated widely. Reflections on the process indicate that there are a variety of structural and functional requirements, as well as enabling conditions, that need to be considered to achieve successful outcomes from synthesis efforts.


Assuntos
Baías , Monitoramento Ambiental , Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Estados Unidos , Qualidade da Água
5.
Proc Biol Sci ; 289(1969): 20211762, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35193403

RESUMO

While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass (Zostera marina) spanning 30° of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change.


Assuntos
Comportamento Predatório , Zosteraceae , Animais , Crustáceos , Ecossistema , Oceanos e Mares
6.
J Pediatr Gastroenterol Nutr ; 72(6): 848-853, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33605658

RESUMO

OBJECTIVES: Four-hour gastric emptying scintigraphy (GES) is the recommended method to identify both adult and childhood gastroparesis (GP). Previous pediatric studies have, however, not used this standard. We sought to determine the characteristics and outcomes of children versus adolescents with GP using the 4-hour GES evaluation. METHODS: We performed a retrospective chart review of pediatric patients diagnosed with GP by 4-hour GES (>10% retention at 4 hours). Demographics, body mass index, GP-related symptoms, comorbidities, etiologies, therapies (eg, medications), healthcare utilization, and response to therapy were captured systematically. Symptoms were compared from the initial versus last gastroenterology visit. Outcomes were categorized as no improvement; improvement (resolution of at least 1 symptom while remaining on therapy); and complete resolution of symptoms. RESULTS: A total of 239 subjects (12.1 ±â€Š4.1 years [mean ±â€Šstandard deviation], 70% girls) were included. The identified characteristics of childhood GP were broad with idiopathic GP being the most common etiology. Outcomes over a median of 22 months (25%-75%: 9.0-45.5 months) were 34.8% no improvement, 34.8% some improvement, and 30.3% with complete symptom resolution. Compared to younger children, adolescents had a higher female predominance (P < 0.01) and were more likely to have nausea (P = 0.006). Girls were more likely to have abdominal pain (P = 0.001), nausea (P = 0.03), and a documented diagnosis of dysautonomia (P = 0.03). Boys were more likely to have regurgitation (P = 0.006), gastroesophageal reflux disease (P = 0.02), and rumination (P = 0.02). CONCLUSIONS: Using the 4-hour GES standard, childhood GP has broad clinical characteristics and outcomes. There are several significant age- and sex-based differences in childhood GP.


Assuntos
Gastroparesia , Adolescente , Adulto , Criança , Feminino , Esvaziamento Gástrico , Gastroparesia/diagnóstico por imagem , Humanos , Masculino , Náusea/etiologia , Cintilografia , Estudos Retrospectivos
8.
Pediatr Emerg Care ; 36(12): 564-570, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33136834

RESUMO

OBJECTIVE: The aim of the study was to examine the ability of overreading of computed tomography (CT) and right lower quadrant ultrasound (RLQ US) to diagnose appendicitis for children with suspected appendicitis with equivocal CTs at community hospitals. METHODS: This was a retrospective chart review of all children transferred to a children's hospital from community emergency departments with suspected appendicitis over 2 years for whom both CT and RLQ US were performed. RESULTS: One hundred eighty-four children were included with a median age of 10.8 years, and 57.6% were female. Community hospitals documented that CTs were equivocal for appendicitis in 110 (59.8%), positive in 63 (34.2%), and negative in 11 (6.0%). Ninety-seven CTs (88.1%) designated equivocal at community hospitals were later deemed interpretable by pediatric radiologists: 21 (19.1%) as appendicitis and 76 (69.1%) as normal. In 13 children (11.8%), both the community and children's hospital CT interpretations were equivocal. In equivocal cases, RLQ US was consistent with appendicitis in 6 (46.2%), normal in 5 (41.7%), and nondiagnostic in 2. κ value between CT interpretations at community versus children's hospital was 0.13 (95% confidence interval, 0.05-0.22), and κ value between CT interpretation at the children's hospital and RLQ US was 0.59 (95% confidence interval, 0.48-0.70). CONCLUSIONS: Most CTs deemed equivocal for appendicitis at community hospitals were interpretable by pediatric radiologists. In a few children for whom CTs were designated nondiagnostic, RLQ US provided a definitive diagnosis in almost 90% of cases. The first step in evaluation of children with suspected appendicitis for whom outside CTs are deemed equivocal should be to have the study reinterpreted by a pediatric radiologist.


Assuntos
Apendicite , Tomografia Computadorizada por Raios X , Ultrassonografia , Apendicite/diagnóstico por imagem , Criança , Feminino , Hospitais Comunitários , Humanos , Masculino , Estudos Retrospectivos
9.
Sci Adv ; 6(41)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33028530

RESUMO

There have been increasing attempts to reverse habitat degradation through active restoration, but few large-scale successes are reported to guide these efforts. Here, we report outcomes from a unique and very successful seagrass restoration project: Since 1999, over 70 million seeds of a marine angiosperm, eelgrass (Zostera marina), have been broadcast into mid-western Atlantic coastal lagoons, leading to recovery of 3612 ha of seagrass. Well-developed meadows now foster productive and diverse animal communities, sequester substantial stocks of carbon and nitrogen, and have prompted a parallel restoration for bay scallops (Argopecten irradians) Restored ecosystem services are approaching historic levels, but we also note that managers value services differently today than they did nine decades ago, emphasizing regulating in addition to provisioning services. Thus, this study serves as a blueprint for restoring and maintaining healthy ecosystems to safeguard multiple benefits, including co-benefits that may emerge as management priorities over time.

10.
Hosp Pediatr ; 10(5): 392-400, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32303562

RESUMO

BACKGROUND: Physicians often obtain a routine renal bladder ultrasound (RBUS) for young children with a first febrile urinary tract infection (UTI). However, few children are diagnosed with serious anatomic anomalies, and opportunity may exist to take a focused approach to ultrasonography. We aimed to identify characteristics of the child, prenatal ultrasound (PNUS), and illness that could be used to predict an abnormal RBUS and measure the impact of RBUS on management. METHODS: We conducted a single-center prospective cohort study of hospitalized children 0 to 24 months of age with a first febrile UTI from October 1, 2016, to December 23, 2018. Independent variables included characteristics of the child, PNUS, and illness. The primary outcome, abnormal RBUS, was defined through consensus of a multidisciplinary team on the severity of ultrasound findings important to identify during a first UTI. RESULTS: A total of 211 children were included; the median age was 1.0 month (interquartile range 0-2), and 55% were uncircumcised boys. All mothers had a PNUS with 10% being abnormal. Escherichia coli was the pathogen in 85% of UTIs, 20% (n = 39 of 197) had bacteremia, and 7% required intensive care. Abnormal RBUS was found in 36% (n = 76 of 211) of children; of these, 47% (n = 36 of 76) had moderately severe findings and 53% (n = 40 of 76) had severe findings. No significant difference in clinical characteristics was seen among children with and without an abnormal RBUS. One child had Foley catheter placement, and 33% received voiding cystourethrograms, 15% antibiotic prophylaxis, and 16% subspecialty referrals. CONCLUSIONS: No clinical predictors were identified to support a focused approach to RBUS examinations. Future studies should investigate the optimal timing for RBUS.


Assuntos
Ultrassonografia , Bexiga Urinária/diagnóstico por imagem , Infecções Urinárias , Criança Hospitalizada , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Bexiga Urinária/patologia , Infecções Urinárias/diagnóstico por imagem
11.
J Am Coll Radiol ; 17(4): 462-468, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31805252

RESUMO

OBJECTIVE: Compare the cost of placing tunneled femoral central lines in the interventional radiology suite to portable bedside placement using time-driven activity-based costing. METHODS: Detailed process maps were created using information generated from interviews with frontline staff, direct shadowing of patient procedures (19 patients-8 in-suite, 11 portable; patient age 4 days to 37 months; 6 males, 13 females), and electronic medical record review (80 patients-44 in-suite, 36 portable; patient age 1 day to 20 months; 42 males, 38 females) who underwent a tunneled femoral central line placement at a tertiary care pediatric hospital from January 1, 2018, to June 30, 2018. Procedures were conducted in-suite using fluoroscopy guidance or portably at the patient's bedside using ultrasound. Capacity cost rates for each resource in the process maps were calculated for personnel, equipment, facilities, and supply costs. Costs for each process step were then calculated by multiplying the capacity cost rate by the mean duration of each step. Stepwise costs were summed for the entire process to generate a cost for each tunneled femoral central line placement pathway. RESULTS: Total pathway time for tunneled femoral central lines placement in-suite was 123 to 134 min (nonsedated) and 120 to 131 min (sedated) for a cost of $923 to $990 and $1,262 to $1,386, respectively. Total pathway time for tunneled femoral central lines placed portably were 117 to 119 min (nonsedated) and 115 to 147 min (sedated) for a cost of $1,060 to $1,066 and $1,379 to $1,393, respectively. CONCLUSION: Total costs of tunneled femoral central lines placed in-suite were similar to total costs for lines placed portably. Cost should not be a primary consideration when deciding upon tunneled femoral central line approach in these patients.


Assuntos
Cateterismo Venoso Central , Criança , Pré-Escolar , Custos e Análise de Custo , Feminino , Fluoroscopia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Ultrassonografia
12.
Sci Rep ; 9(1): 19693, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873181

RESUMO

Seeds of Australian species of the seagrass genus Posidonia are covered by a membranous wing that we hypothesize plays a fundamental role in seed establishment in sandy, wave swept marine environments. Dimensions of the seed and membrane were quantified under electron microscopy and micro-CT scans, and used to model rotational, drag and lift forces. Seeds maintain contact with the seabed in the presence of strong turbulence: the larger the wing, the more stable the seed. Wing surface area increases from P. sinuosa < P. australis < P.coriacea correlating with their ability to establish in increasingly energetic environments. This unique seed trait in a marine angiosperm corresponds to adaptive pressures imposed on seagrass species along 7,500 km of Australia's coastline, from open, high energy coasts to calmer environments in bays and estuaries.


Assuntos
Alismatales/fisiologia , Sementes/fisiologia , Adaptação Fisiológica , Alismatales/anatomia & histologia , Organismos Aquáticos/fisiologia , Austrália , Baías , Simulação por Computador , Ecossistema , Estuários , Hidrodinâmica , Microscopia Eletrônica de Varredura , Modelos Biológicos , Sementes/anatomia & histologia , Microtomografia por Raio-X
13.
Blood Adv ; 3(18): 2689-2695, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31511228

RESUMO

Allogeneic hematopoietic stem cell transplant (HSCT) for relapsed pediatric non-Hodgkin lymphoma (NHL) is often reserved for patients with certain NHL subtypes or high-risk disease whereas the remainder receive autologous HSCT. Given the aggressive nature of pediatric NHL, we performed allogeneic HSCTs for all patients regardless of disease risk. We report overall survival (OS) and prognostic variables in 36 pediatric patients who underwent allogeneic HSCT between 1998 and 2016. OS at 3 years was 67%. The 3-year OS varied based on NHL subtype: 100% for anaplastic large cell lymphoma (n = 14), 63% for diffuse large B-cell lymphoma (n = 8), 17% for lymphoblastic lymphoma (LL; n = 9) and 80% for other subtypes combined (n = 5). Disease status influenced outcome with 3-year OS of 100% for patients in complete remission (n = 15), 59% with partial remission (PR; n = 17), and 0% with progressive/stable disease (n = 3) (P = .004). Of the 17 patients in PR, all 6 with LL died of relapsed disease, whereas the other 11 attained remission after HSCT and remained disease-free. The cumulative incidence of relapse after HSCT for LL was 78% compared with 15% for all other NHL subtypes combined (P < .0001). Cumulative incidence of nonrelapse mortality (NRM) was low in our cohort at 6%. Hence, allogeneic HSCT is a well-tolerated and useful therapeutic option with low rates of NRM and relapse for all NHL subtypes except LL with active disease at HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Linfoma não Hodgkin/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Linfoma não Hodgkin/patologia , Masculino , Recidiva , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
14.
Radiology ; 292(1): 172-178, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31112089

RESUMO

Background Ovarian and adnexal cysts are frequently encountered at US examinations performed in preadolescent and adolescent patients, yet there are few published studies regarding the outcomes of cysts in this population. Purpose To identify characteristics at US that help to distinguish physiologic ovarian cysts from nonphysiologic entities. Materials and Methods Female patients who underwent pelvic US with or without Doppler from January 2009 through December 2013 were identified by using a centralized imaging database. Patients older than 7 years and younger than 18 years with ovarian or adnexal cysts at least 2.5 cm were included. Demographic characteristics, date of surgery, surgical notes, and pathologic reports were extracted from the electronic medical record. Initial and follow-up dates of US, cyst size and complexity, imaging diagnosis, and change on subsequent US images were recorded. Statistical analysis was performed with the Wilcoxon rank sum and Kruskal-Wallis tests for continuous variables and the Fisher exact test for categorical variables. Results Of 754 patients who met inclusion criteria (age, 8-18 years; mean age, 14.6 years ± 1.9 [standard deviation]; mean cyst size, 5 cm ± 3.3), 409 patients underwent complete follow-up that included resolution at imaging (n = 250) or surgery (n = 159). In the patients with complete imaging follow-up, mean time to US documentation of resolution was 194 days ± 321; 59.6% (149 of 250) patients had nonsimple cyst characteristics. One-hundred fifty-nine patients underwent surgical intervention (mean cyst size, 8.5 cm ± 5.3), and 69.8% (111 of 159) of the cysts had simple characteristics. Of the 159 cysts, 100 (62.8%) were defined in the pathologic report as paratubal cysts. Of 409 patients, no malignancies were encountered in this study population with surgical or imaging resolution. Conclusion No malignancies were encountered in the study population and the majority of cysts resolved at follow-up imaging. Large size, persistence, and separability from the ovary were most helpful for identification of nonphysiologic paratubal cysts. © RSNA, 2019.


Assuntos
Cistos Ovarianos/diagnóstico por imagem , Ultrassonografia/métodos , Anexos Uterinos/diagnóstico por imagem , Anexos Uterinos/patologia , Anexos Uterinos/cirurgia , Doenças dos Anexos/diagnóstico por imagem , Doenças dos Anexos/patologia , Doenças dos Anexos/cirurgia , Adolescente , Criança , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Cistos Ovarianos/patologia , Cistos Ovarianos/cirurgia , Ovário/diagnóstico por imagem , Ovário/patologia , Ovário/cirurgia , Estudos Retrospectivos
15.
Acad Radiol ; 26(12): 1618-1624, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31064728

RESUMO

RATIONALE AND OBJECTIVES: To compare the cost of ultrasound (US) versus magnetic resonance imaging (MRI) using time-driven activity-based costing in adolescent female patients with suspected appendicitis. MATERIALS AND METHODS: Process maps were created using data from electronic medical record review and patient shadowing for adolescent female patients undergoing US or noncontrast MRI exams of the abdomen and pelvis for suspected appendicitis. Capacity cost rates for all personnel, equipment, facilities, and supplies in each exam pathway were established from institutional accounting data. The cost of each process step was determined by multiplying step-specific capacity cost rates by the mean time required to complete the step. Total pathway costs for US and MRI were computed by summing the costs of all steps through each pathway, and a direct cost comparison was made between the two modalities. RESULTS: Process maps for US and MRI pathways were generated from 231 and 52 patient encounters, respectively. Patients undergoing US exams followed one of six pathways depending on exam order (abdomen versus pelvis performed first) and whether additional time was needed for bladder filling. Mean total US pathway time was 91 minutes longer than for MRI (US = 166 minutes; MRI = 75 minutes). Total MRI pathway cost was $209.97 compared to a mean US cost of $258.33 (range = $163.21-$293.24). CONCLUSION: MRI can be a faster and less costly alternative to US for evaluating suspected appendicitis in adolescent female patients. While precise costs will vary by institution, MRI may be a viable and at times preferable alternative to US in this patient population.


Assuntos
Dor Abdominal/diagnóstico , Dor Aguda/diagnóstico , Imageamento por Ressonância Magnética/economia , Dor Pélvica/diagnóstico , Ultrassonografia/economia , Adolescente , Criança , Custos e Análise de Custo , Feminino , Humanos
16.
J Pediatr Surg ; 54(11): 2274-2278, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31097307

RESUMO

PURPOSE: Clinical prediction of disease severity is important as one considers nonoperative management of simple appendicitis. This study assesses the accuracy of surgeons' prediction of appendicitis severity. METHODS: From February to August 2016, pediatric surgeons at a single institution were asked to predict whether patients had simple or complex appendicitis preoperatively based on clinical data, imaging, and general assessment. Receiver operating characteristic curves were generated to determine area under the curve (AUC) and optimal cutoff points of clinical findings for diagnosing simple appendicitis. Outcomes included sensitivity and specificity of variables to identify simple appendicitis. Predictions were compared to operative findings using χ2. A p-value<0.05 was considered statistically significant. RESULTS: Of 125 cases (median age 9 years [IQR 7-13], 58% male), simple appendicitis was predicted in 77 (62%) and complex appendicitis in 48 (38%). Predictions were accurate in 59 (77%) simple cases and 45 (94%) complex cases. Although surgeon prediction was more accurate than individual imaging or clinical findings and was highly sensitive (95%) for diagnosing simple appendicitis, specificity was only 71%. Lower WBC (<15.5 × 103/µL, AUC 0.61, p = 0.05), afebrile (<100.4 °F, AUC 0.86, p < 0.01), and shorter symptom duration (≤ 1.5 days, AUC 0.71, p < 0.001) were associated with simple appendicitis. Of 18 complex cases (14%) inaccurately predicted as simple, 17 (94%) lacked diffuse tenderness, 15 (83%) were well-appearing, 11 (61%) had ultrasound findings of simple appendicitis, 11 (61%) had ≤2 days of symptoms, and 8 (44%) were afebrile (<100.4 °F). CONCLUSION: While surgeon prediction of simple appendicitis is more accurate than ultrasound or clinical data alone, diagnostic accuracy is still limited. TYPE OF STUDY: Prospective survey. LEVEL OF EVIDENCE: II.


Assuntos
Apendicite/classificação , Apendicite/diagnóstico , Cirurgiões/estatística & dados numéricos , Adolescente , Apendicite/cirurgia , Criança , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Ultrassonografia
17.
Pediatr Radiol ; 49(3): 429, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30683960

RESUMO

In this article, the fourth author's name is misspelled. The correct spelling, as shown above, should be "Nadia F. Mahmood."

18.
Pediatr Radiol ; 49(1): 76-81, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30232533

RESUMO

BACKGROUND: Ileocolic intussusception occurs when the terminal ileum "telescopes" into the colon. We observed that ileocolic intussusception lengths are similar regardless of location in the colon. OBJECTIVE: To examine the uniformity of ileocolic intussusception length and its relationship to colon location, symptom duration and reducibility. MATERIALS AND METHODS: We retrospectively reviewed ultrasound-diagnosed pediatric ileocolic intussusceptions initially treated with pneumatic reduction at the Mayo Clinic or Texas Children's Hospital. We recorded demographic, imaging and surgical findings including age, gender, symptom duration, location of the ileocolic intussusception, reducibility with air enema and, if fluoroscopically irreducible, surgical findings. RESULTS: We identified 119 ileocolic intussusceptions (64% boys), with 81% in the right colon. There was no significant relationship between ileocolic intussusception length and colon location (P=0.15), nor ileocolic intussusception length and symptom duration (P=0.36). Ileocolic intussusceptions were more distal with increasing symptom duration (P=0.016). Successful reductions were unrelated to symptom duration (P=0.84) but were more likely with proximal versus distal locations (P=0.02). CONCLUSION: Ileocolic intussusception lengths are relatively uniform regardless of location along the course of the colon where they present. Our findings suggest that most of the apparent distal propagation of ileocolic intussusceptions is not caused by increasing telescoping of small bowel across the ileocecal valve but rather by foreshortening of the right colon. This implies poor cecal fixation and confirms fluoroscopic and surgical observations of cecal displacement from the right lower quadrant with ileocolic intussusceptions. The movement of the leading edge of the ileocolic intussusception during reduction is first due to "relocating" the cecum into the right lower quadrant after which the reduction of small bowel back across the ileocecal valve then occurs.


Assuntos
Doenças do Colo/diagnóstico por imagem , Doenças do Íleo/diagnóstico por imagem , Intussuscepção/diagnóstico por imagem , Ultrassonografia/métodos , Doenças do Colo/terapia , Feminino , Humanos , Doenças do Íleo/terapia , Lactente , Intussuscepção/terapia , Masculino , Estudos Retrospectivos , Resultado do Tratamento
19.
Pediatr Radiol ; 49(5): 626-631, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30552437

RESUMO

BACKGROUND: Percutaneous renal biopsy is a commonly performed procedure that guides decision-making for children with renal disease. OBJECTIVE: To compare complications from renal biopsies using real-time ultrasound (US) guidance versus pre-procedure US-aided skin-marking in children. MATERIALS AND METHODS: We conducted a priori power analysis using a risk-adjusted model, which indicated we needed a sample size of 643-714 procedures (effect size: 0.8). Then we retrospectively identified consecutive patients who underwent a percutaneous renal biopsy from Jan. 1, 2012, to Dec. 31, 2016. We categorized complications according to the Society of Interventional Radiology (SIR) criteria and compared rates using the Fisher exact test. We analyzed complication predictors using multivariate regression. RESULTS: The study consisted of 701 percutaneous renal biopsies in 553 patients: 313 used real-time US guidance and 388 used pre-procedure US-aided skin-marking. Among the 254/701 (36%) complications, 56/313 (18%) resulted from real-time US guidance and 198/388 (51%) from pre-procedure US-aided skin-marking (P<0.001). In the US real-time guidance group, 39/56 (70%) complications were SIR A, 8/56 (14%) SIR B, 6/56 (11%) SIR C and 3/56 (5%) SIR D. Among the pre-procedure US-aided skin-marking group, 139/198 (70%) complications were SIR A, 47/198 (24%) SIR B, 11/198 (6%) SIR C and 1/198 (1%) SIR D. Complications between the two groups were significantly different regarding SIR A (P<0.001) and SIR B complications (P<0.001) but not major complications. Multivariate regression demonstrated that complications were higher using US-aided pre-procedure skin-marking (odds ratio [OR]=6.30; 95% confidence interval [CI]=3.86, 10.27) than with US real-time guidance. CONCLUSION: Children and young adults who underwent real-time US-guided percutaneous renal biopsies had significantly fewer minor complications, including those requiring follow-up medical care, compared to those who underwent percutaneous renal biopsies with pre-procedure US-aided skin-marking. No difference was detected in the incidence of major complications.


Assuntos
Biópsia Guiada por Imagem/efeitos adversos , Nefropatias/patologia , Pele , Ultrassonografia de Intervenção , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Nefropatias/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Adulto Jovem
20.
Pediatr Radiol ; 48(13): 1975, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30357424

RESUMO

The original version on this paper contained an error. The names of M. John Hicks and R. Paul Guillerman, though correctly appeared in the published version, are incorrectly displayed in indexing sites.

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