Directed Evolution of a Selective and Sensitive Serotonin Sensor via Machine Learning.

Serotonin plays a central role in cognition and is the target of most pharmaceuticals for psychiatric disorders. Existing drugs have limited efficacy; creation of improved versions will require better understanding of serotonergic circuitry, which has been hampered by our inability to monitor serotonin release and transport with high spatial and temporal resolution. We developed and applied a binding-pocket redesign strategy, guided by machine learning, to create a high-performance, soluble, fluorescent serotonin sensor (iSeroSnFR), enabling optical detection of millisecond-scale serotonin transients. We demonstrate that iSeroSnFR can be used to detect serotonin release in freely behaving mice during fear conditioning, social interaction, and sleep/wake transitions. We also developed a robust assay of serotonin transporter function and modulation by drugs. We expect that both machine-learning-guided binding-pocket redesign and iSeroSnFR will have broad utility for the development of other sensors and in vitro and in vivo serotonin detection, respectively.

Dissecting the Causal Mechanism of X-Linked Dystonia-Parkinsonism by Integrating Genome and Transcriptome Assembly.

X-linked Dystonia-Parkinsonism (XDP) is a Mendelian neurodegenerative disease that is endemic to the Philippines and is associated with a founder haplotype. We integrated multiple genome and transcriptome assembly technologies to narrow the causal mutation to the TAF1 locus, which included a SINE-VNTR-Alu (SVA) retrotransposition into intron 32 of the gene. Transcriptome analyses identified decreased expression of the canonical cTAF1 transcript among XDP probands, and de novo assembly across multiple pluripotent stem-cell-derived neuronal lineages discovered aberrant TAF1 transcription that involved alternative splicing and intron retention (IR) in proximity to the SVA that was anti-correlated with overall TAF1 expression. CRISPR/Cas9 excision of the SVA rescued this XDP-specific transcriptional signature and normalized TAF1 expression in probands. These data suggest an SVA-mediated aberrant transcriptional mechanism associated with XDP and may provide a roadmap for layered technologies and integrated assembly-based analyses for other unsolved Mendelian disorders.

Functional antibodies exhibit light chain coherence.

The vertebrate adaptive immune system modifies the genome of individual B cells to encode antibodies that bind particular antigens1. In most mammals, antibodies are composed of heavy and light chains that are generated sequentially by recombination of V, D (for heavy chains), J and C gene segments. Each chain contains three complementarity-determining regions (CDR1-CDR3), which contribute to antigen specificity. Certain heavy and light chains are preferred for particular antigens2-22. Here we consider pairs of B cells that share the same heavy chain V gene and CDRH3 amino acid sequence and were isolated from different donors, also known as public clonotypes23,24. We show that for naive antibodies (those not yet adapted to antigens), the probability that they use the same light chain V gene is around 10%, whereas for memory (functional) antibodies, it is around 80%, even if only one cell per clonotype is used. This property of functional antibodies is a phenomenon that we call light chain coherence. We also observe this phenomenon when similar heavy chains recur within a donor. Thus, although naive antibodies seem to recur by chance, the recurrence of functional antibodies reveals surprising constraint and determinism in the processes of V(D)J recombination and immune selection. For most functional antibodies, the heavy chain determines the light chain.

Dorsal root ganglia control nociceptive input to the central nervous system.

Accumulating observations suggest that peripheral somatosensory ganglia may regulate nociceptive transmission, yet direct evidence is sparse. Here, in experiments on rats and mice, we show that the peripheral afferent nociceptive information undergoes dynamic filtering within the dorsal root ganglion (DRG) and suggest that this filtering occurs at the axonal bifurcations (t-junctions). Using synchronous in vivo electrophysiological recordings from the peripheral and central processes of sensory neurons (in the spinal nerve and dorsal root), ganglionic transplantation of GABAergic progenitor cells, and optogenetics, we demonstrate existence of tonic and dynamic filtering of action potentials traveling through the DRG. Filtering induced by focal application of GABA or optogenetic GABA release from the DRG-transplanted GABAergic progenitor cells was specific to nociceptive fibers. Light-sheet imaging and computer modeling demonstrated that, compared to other somatosensory fiber types, nociceptors have shorter stem axons, making somatic control over t-junctional filtering more efficient. Optogenetically induced GABA release within DRG from the transplanted GABAergic cells enhanced filtering and alleviated hypersensitivity to noxious stimulation produced by chronic inflammation and neuropathic injury in vivo. These findings support "gating" of pain information by DRGs and suggest new therapeutic approaches for pain relief.

Cutaneous Coccidiomycosis.

ABSTRACT: Coccidiomycosis is an infectious primary pulmonary disease caused by two highly virulent fungi, Coccidioides immitis and C. Posadasii. Coccidioides spp. are endemic to the southwestern USA, Central America, and South America with infection predominating in the summer and fall seasons. The disease commonly presents with flu-like symptoms. Cutaneous manifestations are rare and are a sign of a more serious infection with poorer outcomes. In this case, a 60-year-old female presented to the dermatology clinic with a 3-month history of a mild, non-pruritic, erythematous rash located on her proximal arms and legs. Two punch biopsies were obtained, and she was found to have a non-endemic case of disseminated coccidiomycosis.

Hammertoe correction with wire fixation of varying length.

BACKGROUND: Proximal interphalangeal (PIP) joint fusion with Kirschner (K) -wire fixation remains a popular strategy for hammertoe correction. This study was performed to evaluate the effect of length of wire fixation on clinical outcomes. METHODS: A retrospective review of all hammertoe reconstructions by a single surgeon was performed. Wire length was chosen at the surgeon's discretion. Outcomes were assessed with metatarsophalangeal (MTP) congruency, pin complications, and PIP union. RESULTS: 157 toes underwent reconstruction. Seventy had wires that spanned the MTP and 87 that did not. Wire breaks were significantly more common with longer wire fixation (P = .024). MTP incongruency was significantly more common in the MTP group (P = .014). CONCLUSION: Pin breakage was rare and only occurred in the MTP group. MTP incongruence was significantly more common in the MTP group but may not reflect surgical technique. PIP union was more common with longer wire fixation but is not clinically significant. LEVEL OF EVIDENCE: III.

Radiographic Pneumonia in Febrile Infants 60 Days and Younger.

OBJECTIVE: Few prospective studies have assessed the occurrence of radiographic pneumonia in young febrile infants. We analyzed factors associated with radiographic pneumonias in febrile infants 60 days or younger evaluated in pediatric emergency departments. STUDY DESIGN: We conducted a planned secondary analysis of a prospective cohort study within 26 emergency departments in a pediatric research network from 2008 to 2013. Febrile (≥38°C) infants 60 days or younger who received chest radiographs were included. Chest radiograph reports were categorized as "no," "possible," or "definite" pneumonia. We compared demographics, Yale Observation Scale scores (>10 implying ill appearance), laboratory markers, blood cultures, and viral testing among groups. RESULTS: Of 4778 infants, 1724 (36.1%) had chest radiographs performed; 2.7% (n = 46) had definite pneumonias, and 3.9% (n = 67) had possible pneumonias. Patients with definite (13/46 [28.3%]) or possible (15/67 [22.7%]) pneumonias more frequently had Yale Observation Scale score >10 compared with those without pneumonias (210/1611 [13.2%], P = 0.002) in univariable and multivariable analyses. Median white blood cell count (WBC), absolute neutrophil count (ANC), and procalcitonin (PCT) were higher in the definite (WBC, 11.5 [interquartile range, 9.8-15.5]; ANC, 5.0 [3.2-7.6]; PCT, 0.4 [0.2-2.1]) versus no pneumonia (WBC, 10.0 [7.6-13.3]; ANC, 3.4 [2.1-5.4]; PCT, 0.2 [0.2-0.3]; WBC, P = 0.006; ANC, P = 0.002; PCT, P = 0.046) groups, but of unclear clinical significance. There were no cases of bacteremia in the definite pneumonia group. Viral infections were more frequent in groups with definite (25/38 [65.8%]) and possible (28/55 [50.9%]) pneumonias than no pneumonias (534/1185 [45.1%], P = 0.02). CONCLUSIONS: Radiographic pneumonias were uncommon, often had viruses detected, and were associated with ill appearance, but few other predictors, in febrile infants 60 days or younger.

Direct determination of diploid genome sequences.

Determining the genome sequence of an organism is challenging, yet fundamental to understanding its biology. Over the past decade, thousands of human genomes have been sequenced, contributing deeply to biomedical research. In the vast majority of cases, these have been analyzed by aligning sequence reads to a single reference genome, biasing the resulting analyses, and in general, failing to capture sequences novel to a given genome. Some de novo assemblies have been constructed free of reference bias, but nearly all were constructed by merging homologous loci into single "consensus" sequences, generally absent from nature. These assemblies do not correctly represent the diploid biology of an individual. In exactly two cases, true diploid de novo assemblies have been made, at great expense. One was generated using Sanger sequencing, and one using thousands of clone pools. Here, we demonstrate a straightforward and low-cost method for creating true diploid de novo assemblies. We make a single library from ∼1 ng of high molecular weight DNA, using the 10x Genomics microfluidic platform to partition the genome. We applied this technique to seven human samples, generating low-cost HiSeq X data, then assembled these using a new "pushbutton" algorithm, Supernova. Each computation took 2 d on a single server. Each yielded contigs longer than 100 kb, phase blocks longer than 2.5 Mb, and scaffolds longer than 15 Mb. Our method provides a scalable capability for determining the actual diploid genome sequence in a sample, opening the door to new approaches in genomic biology and medicine.

The genomic substrate for adaptive radiation in African cichlid fish.

Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand the molecular mechanisms underlying cichlid phenotypic diversity, we sequenced the genomes and transcriptomes of five lineages of African cichlids: the Nile tilapia (Oreochromis niloticus), an ancestral lineage with low diversity; and four members of the East African lineage: Neolamprologus brichardi/pulcher (older radiation, Lake Tanganyika), Metriaclima zebra (recent radiation, Lake Malawi), Pundamilia nyererei (very recent radiation, Lake Victoria), and Astatotilapia burtoni (riverine species around Lake Tanganyika). We found an excess of gene duplications in the East African lineage compared to tilapia and other teleosts, an abundance of non-coding element divergence, accelerated coding sequence evolution, expression divergence associated with transposable element insertions, and regulation by novel microRNAs. In addition, we analysed sequence data from sixty individuals representing six closely related species from Lake Victoria, and show genome-wide diversifying selection on coding and regulatory variants, some of which were recruited from ancient polymorphisms. We conclude that a number of molecular mechanisms shaped East African cichlid genomes, and that amassing of standing variation during periods of relaxed purifying selection may have been important in facilitating subsequent evolutionary diversification.

Ligation-assisted endoscopic mucosal resection for esophageal granular cell tumors is safe and effective.

Given their malignant potential, resection of esophageal granular cell tumors (GCTs) is often undertaken, yet the optimal technique is unknown. We present a large series of dedicated endoscopic resection using band ligation (EMR-B) of esophageal GCTs. Patients diagnosed with esophageal GCTs between 2002 and 2019 were identified using a prospectively collected pathology database. Endoscopic reports were reviewed, and patients who underwent dedicated EMR-B of esophageal GCTs were included. Medical records were queried for demographics, findings, adverse events, and follow-up. We identified 21 patients who underwent dedicated EMR-B for previously identified esophageal GCT. Median age was 39 years; 16 (76%) were female. Eight (38%) had preceding signs or symptoms, potentially attributable to the GCT. Upon endoscopic evaluation, 12 (57%) were found in the distal esophagus. Endoscopic ultrasound was used in 15 cases (71%). Median lesion size was 7 mm, interquartile range 4 mm-8 mm. The largest lesion was 12 mm. A total of 20 (95%) had en bloc resection confirmed with pathologic examination. The only patient with tumor extending to the resection margin underwent surveillance endoscopy that showed no residual tumor. No patients experienced bleeding, perforation, or stricturing in our series. No patients have had known recurrence of their esophageal GCT. EMR-B of esophageal GCT achieves complete histopathologic resection with minimal adverse events. EMR-B is safe and effective and seems prudent compared with observation for what could be an aggressive and malignant tumor. EMR-B should be considered first-line therapy when resecting esophageal GCT up to 12 mm in diameter.

Patient Factors Associated With the Decision to Transfer Adult Patients From a Pediatric Emergency Department for Definitive Care.

OBJECTIVE: Adults presenting to pediatric emergency departments are transferred to general emergency departments in proportions between 20% and 60%. How illness severity is related to the decision to transfer is poorly understood. We compared the proportion of adults with emergent and nonemergent conditions with respect to their final disposition. We also determined characteristics associated with transfer. METHODS: We conducted a retrospective review of the electronic medical record and identified all patients 25 years and older presenting to a large urban freestanding pediatric emergency department from 2008 to 2013. We collected demographic and clinical information and used a preexisting algorithm to classify visits as emergent or nonemergent. We created a multivariate logistical regression model to determine independent variables associated with transfer. RESULTS: Among 246,694 encounters, 1182 (0.5%) patients were older than 25 years. We excluded 402 (34%) because they were not categorized. Of the 780 categorized, 32% had an emergent and 68% had a nonemergent condition. Only 22% were transferred. Compared with nonurgent patients, the proportion transferred was twice as high for emergent patients (36% vs 15%), but even for emergent patients, most (63%) were retained for definitive care and/or disposition. Emergent diagnosis, age 45 to 64 years, and higher triage acuity were independently associated with the decision to transfer. CONCLUSION: Regardless of illness severity, a minority of adult patients were transferred away for definitive care. Factors independently associated with transfer were emergent condition, higher triage acuity, and older age.

Rapid Administration of Ketamine for Abscess Drainage in Children-A Dose Finding Study.

STUDY OBJECTIVE: To estimate the minimum dose and total sedation time of rapidly infused ketamine that achieves 3 to 5 minutes of effective sedation in children undergoing abscess incision and drainage in the emergency department. METHODS: The Up-Down method was used to estimate the dose of intravenous ketamine infused over 5 seconds or less that provided effective sedation in 50% (ED50) and 95% (ED95) for healthy children aged 2 to 5 years and 6 to 11 years undergoing abscess incision and drainage. None were pretreated with opioids. Three investigators blinded to ketamine dose independently graded sedation effectiveness by viewing a video recording of the first 5 minutes of sedation. Recovery was determined when patients reached a Modified Aldrete score of 10. RESULTS: We enrolled 20 children in each age group. The estimated ED50 was 0.9 and 0.6 mg/kg for the 2 to 5 years and 6 to 11 years' groups and the estimated ED95 was 1.1 mg/kg for both groups. The median time to full recovery for the 2 groups was 20.5 and 17.5 minutes when only 1 dose of ketamine was administered and 27.5 and 35 minutes when additional doses of ketamine were administered. No participants experienced serious adverse events. CONCLUSIONS: We estimated ED50 and ED95 for rapidly infused ketamine for 2 age groups undergoing abscess incision and drainage. Further studies are needed to get a more precise estimate of ED95. The total sedation time with this technique in the abscess group was shorter than most previous studies and is consistent with our previous observations in patients undergoing fracture reduction.

Failure of Indomethacin and Radiation to Prevent Blast-induced Heterotopic Ossification in a Sprague-Dawley Rat Model.

BACKGROUND: Although use of nonsteroidal antiinflammatory drugs and low-dose irradiation has demonstrated efficacy in preventing heterotopic ossification (HO) after THA and surgical treatment of acetabular fractures, these modalities have not been assessed after traumatic blast amputations where HO is a common complication that can arise in the residual limb. QUESTIONS/PURPOSES: The purpose of this study was to investigate the effectiveness of indomethacin and irradiation in preventing HO induced by high-energy blast trauma in a rat model. METHODS: Thirty-six Sprague-Dawley rats underwent hind limb blast amputation with a submerged explosive under water followed by irrigation and primary wound closure. One group (n = 12) received oral indomethacin for 10 days starting on postoperative Day 1. Another group (n = 12) received a single dose of 8 Gy irradiation to the residual limb on postoperative Day 3. A control group (n = 12) did not receive either. Wound healing and clinical course were monitored in all animals until euthanasia at 24 weeks. Serial radiographs were taken immediately postoperatively, at 10 days, and every 4 weeks thereafter to monitor the time course of ectopic bone formation until euthanasia. Five independent graders evaluated the 24-week radiographs to quantitatively assess severity and qualitatively assess the pattern of HO using a modified Potter scale from 0 to 3. Assessment of grading reproducibility yielded a Fleiss statistic of 0.41 and 0.37 for severity and type, respectively. By extrapolation from human clinical trials, a minimum clinically important difference in HO severity was empirically determined to be two full grades or progression of absolute grade to the most severe. RESULTS: We found no differences in mean HO severity scores among the three study groups (indomethacin 0.90 ± 0.46 [95% confidence interval {CI}, 0.60-1.19]; radiation 1.34 ± 0.59 [95% CI, 0.95-1.74]; control 0.95 ± 0.55 [95% CI, 0.60-1.30]; p = 0.100). For qualitative HO type scores, the radiation group had a higher HO type than both indomethacin and controls, but indomethacin was no different than controls (indomethacin 1.08 ± 0.66 [95% CI, 0.67-1.50]; radiation 1.89 ± 0.76 [95% CI, 1.38-2.40]; control 1.10 ± 0.62 [95% CI, 0.70-1.50]; p = 0.013). The lower bound of the 95% CI on mean severity in the indomethacin group and the upper bound of the radiation group barely spanned a full grade and involved only numeric grades < 2, suggesting that even if a small difference in severity could be detected, it would be less than our a priori-defined minimum clinically important difference and any differences that might be present are unlikely to be clinically meaningful. CONCLUSIONS: This work unexpectedly demonstrated that, compared with controls, indomethacin and irradiation provide no effective prophylaxis against HO in the residual limb after high-energy blast amputation in a rat model. Such an observation is contrary to the civilian experience and may be potentially explained by either a different pathogenesis for blast-induced HO or a stimulus that overwhelms conventional regimens used to prevent HO in the civilian population. CLINICAL RELEVANCE: HO in the residual limb after high-energy traumatic blast amputation will likely require novel approaches for prevention and management.

Unipolar allograft reconstruction for post-traumatic avascular necrosis of the distal tibia: A review of the literature, technique, and case series.

BACKGROUND: Avascular necrosis of the distal tibial plafond following ankle trauma is an underreported and potentially devastating phenomenon. Beyond conservative treatment options, surgical intervention has been limited to ankle arthrodesis, which sacrifices motion and may have longterm sequellae for adjacent hindfoot joints. Total ankle replacement has been historically contraindicated. Unipolar allograft reconstruction provides an option for joint salvage. We present a literature overview, implantation technique, and two cases utilizing matched unipolar distal tibial allograft. METHODS: Two younger patients underwent distal tibia allograft reconstruction for tibial plafond collapse due to post-traumatic avascular necrosis. They were followed to assess for clinical improvement and radiographic graft subsidence. RESULTS: Both patients returned to work and activity. One patient had no graft subsidence at four years, but the other patient became symptomatic with graft subsidence at one year. CONCLUSIONS: Distal tibia allograft reconstruction can be utilized as a joint salvage surgery for post-traumatic avascular necrosis with collapse of the tibial plafond in younger patients that prefer an alternative to arthrodesis. Results may be mixed and necessitate an engaged, activated patient. LEVEL OF EVIDENCE: IV.

A computational model for how the fast afterhyperpolarization paradoxically increases gain in regularly firing neurons.

The gain of a neuron, the number and frequency of action potentials triggered in response to a given amount of depolarizing injection, is an important behavior underlying a neuron's function. Variations in action potential waveform can influence neuronal discharges by the differential activation of voltage- and ion-gated channels long after the end of a spike. One component of the action potential waveform, the afterhyperpolarization (AHP), is generally considered an inhibitory mechanism for limiting firing rates. In dentate gyrus granule cells (DGCs) expressing fast-gated BK channels, large fast AHPs (fAHP) are paradoxically associated with increased gain. In this article, we describe a mechanism for this behavior using a computational model. Hyperpolarization provided by the fAHP enhances activation of a dendritic inward current (a T-type Ca2+ channel is suggested) that, in turn, boosts rebound depolarization at the soma. The model suggests that the fAHP may both reduce Ca2+ channel inactivation and, counterintuitively, enhance its activation. The magnitude of the rebound depolarization, in turn, determines the activation of a subsequent, slower inward current (a persistent Na+ current is suggested) limiting the interspike interval. Simulations also show that the effect of AHP on gain is also effective for physiologically relevant stimulation; varying AHP amplitude affects interspike interval across a range of "noisy" stimulus frequency and amplitudes. The mechanism proposed suggests that small fAHPs in DGCs may contribute to their limited excitability. NEW & NOTEWORTHY The afterhyperpolarization (AHP) is canonically viewed as a major factor underlying the refractory period, serving to limit neuronal firing rate. We recently reported that enhancing the amplitude of the fast AHP (fAHP) in a relatively slowly firing neuron (vs. fast spiking neurons) expressing fast-gated BK channels augments neuronal excitability. In this computational study, we present a novel, quantitative hypothesis for how varying the amplitude of the fAHP can, paradoxically, influence a subsequent spike tens of milliseconds later.

Epidemiology of Bacteremia in Febrile Infants Aged 60 Days and Younger.

STUDY OBJECTIVE: To describe the current epidemiology of bacteremia in febrile infants 60 days of age and younger in the Pediatric Emergency Care Applied Research Network (PECARN). METHODS: We conducted a planned secondary analysis of a prospective observational study of febrile infants 60 days of age and younger presenting to any of 26 PECARN emergency departments (2008 to 2013) who had blood cultures obtained. We excluded infants with significant comorbidities or critically ill appearance. The primary outcome was prevalence of bacteremia. RESULTS: Of 7,335 screened infants, 4,778 (65.1%) had blood cultures and were enrolled. Of these patients, 84 had bacteremia (1.8%; 95% confidence interval [CI] 1.4% to 2.2%). The prevalence of bacteremia in infants aged 28 days or younger (47/1,515) was 3.1% (95% CI 2.3% to 4.1%); in infants aged 29 to 60 days (37/3,246), 1.1% (95% CI 0.8% to 1.6%). Prevalence differed by week of age for infants 28 days of age and younger (0 to 7 days: 4/156, 2.6%; 8 to 14 days: 19/356, 5.3%; 15 to 21 days: 15/449, 3.3%; and 22 to 28 days: 9/554, 1.6%). The most common pathogens were Escherichia coli (39.3%; 95% CI 29.5% to 50.0%) and group B streptococcus (23.8%; 95% CI 16.0% to 33.9%). Bacterial meningitis occurred in 19 of 1,515 infants 28 days of age and younger (1.3%; 95% CI 0.8% to 2.0%) and 5 of 3,246 infants aged 29 to 60 days (0.2%; 95% CI 0.1% to 0.4%). Of 84 infants with bacteremia, 36 (42.9%; 95% CI 32.8% to 53.5%) had urinary tract infections (E coli 83%); 11 (13.1%; 95% CI 7.5% to 21.9%) had bacterial meningitis. CONCLUSION: The prevalence of bacteremia and meningitis among febrile infants 28 days of age and younger is high and exceeds that observed in infants aged 29 to 60 days. E coli and group B streptococcus are the most common bacterial pathogens.

The genomic basis of adaptive evolution in threespine sticklebacks.

Marine stickleback fish have colonized and adapted to thousands of streams and lakes formed since the last ice age, providing an exceptional opportunity to characterize genomic mechanisms underlying repeated ecological adaptation in nature. Here we develop a high-quality reference genome assembly for threespine sticklebacks. By sequencing the genomes of twenty additional individuals from a global set of marine and freshwater populations, we identify a genome-wide set of loci that are consistently associated with marine-freshwater divergence. Our results indicate that reuse of globally shared standing genetic variation, including chromosomal inversions, has an important role in repeated evolution of distinct marine and freshwater sticklebacks, and in the maintenance of divergent ecotypes during early stages of reproductive isolation. Both coding and regulatory changes occur in the set of loci underlying marine-freshwater evolution, but regulatory changes appear to predominate in this well known example of repeated adaptive evolution in nature.

Characteristics of youth agreeing to electronic sexually transmitted infection risk assessment in the emergency department.

OBJECTIVES: Adolescents and young adults are at high risk for sexually transmitted infections (STIs). We previously reported an increase in STI testing of adolescents in our ED by obtaining a sexual history using an Audio-enhanced Computer-Assisted Self-Interview (ACASI). We now examine associations among demographics, sexual behaviour, chief complaint and willingness to be tested. METHODS: This was a prospective study conducted in a paediatric ED between April and December 2011. After triage, eligible patients between 15 and 21 years presenting with non-life-threatening conditions were asked to participate in the study. Consenting participants used an ACASI to provide their demographic data and answer questions about their sexual history and willingness to be tested. Our primary outcome was the association of demographics, chief complaint and ACASI recommendation with the participant's willingness to be tested. RESULTS: We approached 1337 patients, of whom 800 (59%) enrolled and completed the ACASI. Eleven who did not answer questions related to their sexual history were excluded from analysis. Of 789 participants, 461 (58.4%) were female and median age was 16.9 years (IQR 16.0-17.8); 509 (64.5%) endorsed a history of anal, oral and/or vaginal intercourse. Disclosing a sexual history and willingness to be tested did not differ significantly by gender. 131 (16.6%) had a chief complaint potentially referable to an STI; among the 658 participants with non-STI-related complaints, 412 (62.6%) were sexually active, many of whom disclosed risky behaviours, including multiple partners (46.4%) and inconsistent condom use (43.7%). The ACASI identified 419 patients as needing immediate STI testing; the majority (81%) did not have a chief complaint potentially related to STIs. 697 (88.3%) participants were willing to receive STI testing. Most (94.6%) of the patients with STI-related complaints were willing to be tested, and 92.1% of patients with a recommendation for immediate testing by the ACASI indicated a willingness to be tested. CONCLUSIONS: Adolescents were willing to disclose sexual activity via electronic questionnaires and were willing to receive STI testing, even when their chief complaint was not STI related. The ACASI facilitated identification of adolescent ED patients needing STI testing regardless of chief complaint.

Cervical Spine Injuries in Children Associated With Sports and Recreational Activities.

OBJECTIVE: The aim of this study was to ascertain potential factors associated with cervical spine injuries in children injured during sports and recreational activities. METHODS: This is a secondary analysis of a multicenter retrospective case-control study involving children younger than 16 years who presented to emergency departments after blunt trauma and underwent cervical spine radiography. Cases had cervical spine injury from sports or recreational activities (n = 179). Comparison groups sustained (1) cervical spine injury from other mechanisms (n = 361) or (2) other injuries from sports and recreational activities but were free of cervical spine injury (n = 180). RESULTS: For children with sport and recreational activity-related cervical spine injuries, common injury patterns were subaxial (49%) and fractures (56%). These children were at increased odds of spinal cord injury without radiographic abnormalities compared with children with cervical spine injuries from other mechanisms (25% vs 6%). Children with sport and recreational activity-related trauma had increased odds of cervical spine injury if they had focal neurologic findings (odds ratio [OR], 5.7; 95% confidence interval [CI], 3.5-9.4), had complaints of neck pain (OR, 3.1; 95% CI, 1.9-5.0), were injured diving (OR, 43.5; 95% CI, 5.9-321.3), or sustained axial loading impacts (OR, 2.2; 95% CI, 1.3-3.5). Football (22%), diving (20%), and bicycle crashes (11%) were the leading activities associated with cervical spine injury. CONCLUSIONS: In children injured during sports and recreational activities, focal neurologic findings, neck pain, axial loading impacts, and the possibility of spinal cord injury without radiographic abnormality should guide the diagnostic evaluation for potential cervical spine injuries. Certain activities have a considerable frequency of cervical spine injury, which may benefit from activity-specific preventive measures.

Rectal Indomethacin Reduces Pancreatitis in High- and Low-Risk Patients Undergoing Endoscopic Retrograde Cholangiopancreatography.

BACKGROUND & AIMS: Rectal indomethacin reduces the risk of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). Most studies of its efficacy included high-risk cohorts and excluded low-risk patients, including those with malignant biliary obstruction. We investigated the potential of rectal indomethacin to prevent post-ERCP pancreatitis (PEP) in a variety of patients. METHODS: We performed a retrospective cohort study of 4017 patients who underwent ERCP at the Hospital of the University of Pennsylvania, from 2009 and 2015, including 823 patients with malignant biliary obstruction. After June 2012, with a few exceptions, patients received indomethacin after their procedure. We collected data from patients' records on demographic and clinical features, procedures, and development of PEP. PEP was defined by consensus criteria. Multivariable logistic regression was used to determine adjusted odds ratios (ORs) for the association between indomethacin and PEP. RESULTS: Rectal indomethacin reduced the odds of PEP by 65% (OR, 0.35; 95% confidence interval [CI], 0.24-0.51; P < .001) and moderate-to-severe PEP by 83% (OR, 0.17; 95% CI, 0.09-0.32; P < .001). In patients with malignant obstruction, rectal indomethacin reduced the risk of PEP by 64% (OR, 0.36; 95% CI, 0.17-0.75; P < .001) and moderate-to-severe PEP by 80% (OR, 0.20; 95% CI, 0.07-0.63; P < .001). Among patients with malignant obstruction, rectal indomethacin provided the greatest benefit to patients with pancreatic adenocarcinoma: 2.31% of these patients who received rectal indomethacin developed PEP vs 7.53% who did not receive rectal indomethacin (P < .001) and 0.59% of these patients who received rectal indomethacin developed moderate-to-severe PEP vs 4.32% who did not receive rectal indomethacin (P = .001). CONCLUSIONS: In a large retrospective cohort study of patients undergoing ERCP that included low-risk patients and patients with malignant biliary obstruction, rectal indomethacin was associated with a significant decrease in the absolute rate and severity of pancreatitis.