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Summary Background Disparities in involuntary psychiatric hospitalisation between population subgroups have been identified in adults, but little is known about the factors associated with involuntary hospitalisation in children or adolescents. We did a systematic review, meta-analysis, and narrative synthesis to investigate the social and clinical factors associated with involuntary psychiatric hospitalisation among children and adolescents. Methods We searched MEDLINE, PsycINFO, Embase, and the Cochrane Central Register of Controlled Trials for studies of any type up to July 22, 2020, that compared the characteristics of voluntary and involuntary psychiatric inpatients (mean age of sample ≤18 years). We synthesised results using random effects meta-analysis on unadjusted data and by narrative synthesis. Heterogeneity between studies was calculated using I2. This study is registered on PROSPERO, CRD42020099892. Findings 23 studies from 11 countries were included in the systematic review and narrative synthesis, of which 19 studies (n=31 212) were included in the meta-analysis. On meta-analysis, involuntary rather than voluntary hospitalisation of minors was associated with a diagnosis of psychosis (eight studies; odds ratio 3·63, 95% CI 2·43–5·44, p

This article provides an organization of various kinds of biases that can occur in the AI pipeline starting from dataset creation and problem formulation to data analysis and evaluation. It highlights the challenges associated with the design of bias-mitigation strategies, and it outlines some best practices suggested by researchers. Finally, a set of guidelines is presented that could aid ML developers in identifying potential sources of bias, as well as avoiding the introduction of unwanted biases. The work is meant to serve as an educational resource for ML developers in handling and addressing issues related to bias in AI systems.

Summary Objective To compare early hip osteoarthritis (OA) features on magnetic resonance imaging (MRI) in high-impact athletes with and without hip and/or groin pain, and to evaluate associations between early hip OA features, the International Hip Outcome Tool (iHOT33) and Copenhagen Hip and Groin Outcome Score (HAGOS). Design This case-control study evaluated data of the femoroacetabular impingement and hip osteoarthritis cohort (FORCe). One hundred and eighty-two symptomatic (hip and/or groin pain >6 months and positive flexion-adduction-internal-rotation (FADIR) test) and 55 pain-free high-impact athletes (soccer or Australian football (AF)) without definite radiographic hip OA underwent hip MRI. The Scoring Hip Osteoarthritis with MRI (SHOMRI) method quantified and graded the severity of OA features. Each participant completed the iHOT33 and HAGOS. Results Hip and/or groin pain was associated with higher total SHOMRI (0–96) (mean difference 1.4, 95% CI: 0.7–2.2), labral score (adjusted incidence rate ratio (aIRR) 1.33, 95% CI: 1.1–1.6). Differences in prevalence of cartilage defects, labral tears and paralabral cysts between symptomatic and pain-free participants were inconclusive. There was a lower prevalence of effusion-synovitis in symptomatic participants when compared to pain-free participants (adjusted odds ratio (aOR) 0.46 (95% CI: 0.3–0.8). Early hip OA features were not associated with iHOT33 or HAGOS. Conclusions A complex and poorly understood relationship exists between hip and/or groin pain and early hip OA features present on MRI in high-impact athletes without radiographic OA. Hip and/or groin pain was associated with higher SHOMRI and labral scores.

BackgroundCognitive mechanisms that characterize or precede depressive symptoms are poorly understood. We investigated cross-sectional and longitudinal associations between risk taking to obtain reward and adolescent depressive symptoms in a large prospective cohort, using the Cambridge Gambling Task (CGT). We also explored sex differences.MethodsThe Millennium Cohort Study (MCS) is an ongoing UK study, following the lives of 19 000 individuals born 2000/02. The CGT was completed at ages 11 (n = 12 355) and 14 (n = 10 578). Our main exposure was the proportion of points gambled, when the odds of winning were above chance (risk-taking to obtain reward). Outcomes were emotional symptoms (Strengths and Difficulties Questionnaire, SDQ) at age 11 and depressive symptoms (short Mood and Feelings Questionnaire, sMFQ) at age 14. We calculated cross-sectional and longitudinal associations, using linear regressions.ResultsIn univariable models, there was evidence of cross-sectional associations between risk-taking and SDQ/sMFQ scores, but these associations disappeared after we adjusted for sex. Longitudinally, there was weak evidence of an association between risk-taking and depressive symptoms in females only [a 20-point increase in risk-taking at age 11 was associated with a reduction of 0.31 sMFQ points at age 14 (95% CI −0.60 to −0.02)]. At both time-points, females were less risk-taking than males.ConclusionsWe found no convincing evidence of a relationship between risk-taking to obtain reward and depressive symptoms. There were large sex differences in risk-taking, but these do not appear to contribute to the female preponderance of depressive symptoms in adolescence.

Fallopian tube fistula with the bladder can mimic an enterovaginal fistula. A 34-year-old woman presented with continuous urinary incontinence after hysterectomy. A cystogram confirmed a vesicovaginal fistula and a possible additional intestinal communication. Further imaging, however, ruled out an enterovaginal fistula and diagnosed a fallopian tube prolapse with salpingovesicovaginal fistula. This case demonstrates the importance of multiple imaging modalities in identifying and clearly delineating the anatomy of gynecologic fistulous connections. The case illustrates the fact that while salpingovesical fistula is a rare complication of hysterectomy, it is an important consideration in one's differential diagnosis.

BACKGROUND Accurate interpretation of hip MRI is time-intensive and difficult, prone to inter- and intrareviewer variability, and lacks a universally accepted grading scale to evaluate morphological abnormalities. PURPOSE To 1) develop and evaluate a deep-learning-based model for binary classification of hip osteoarthritis (OA) morphological abnormalities on MR images, and 2) develop an artificial intelligence (AI)-based assist tool to find if using the model predictions improves interreader agreement in hip grading. STUDY TYPE Retrospective study aimed to evaluate a technical development. POPULATION A total of 764 MRI volumes (364 patients) obtained from two studies (242 patients from LASEM [FORCe] and 122 patients from UCSF), split into a 65-25-10% train, validation, test set for network training. FIELD STRENGTH/SEQUENCE 3T MRI, 2D T2 FSE, PD SPAIR. ASSESSMENT Automatic binary classification of cartilage lesions, bone marrow edema-like lesions, and subchondral cyst-like lesions using the MRNet, interreader agreement before and after using network predictions. STATISTICAL TESTS Receiver operating characteristic (ROC) curve, area under curve (AUC), specificity and sensitivity, and balanced accuracy. RESULTS For cartilage lesions, bone marrow edema-like lesions and subchondral cyst-like lesions the AUCs were: 0.80 (95% confidence interval [CI] 0.65, 0.95), 0.84 (95% CI 0.67, 1.00), and 0.77 (95% CI 0.66, 0.85), respectively. The sensitivity and specificity of the radiologist for binary classification were: 0.79 (95% CI 0.65, 0.93) and 0.80 (95% CI 0.59, 1.02), 0.40 (95% CI -0.02, 0.83) and 0.72 (95% CI 0.59, 0.86), 0.75 (95% CI 0.45, 1.05) and 0.88 (95% CI 0.77, 0.98). The interreader balanced accuracy increased from 53%, 71% and 56% to 60%, 73% and 68% after using the network predictions and saliency maps. DATA CONCLUSION We have shown that a deep-learning approach achieved high performance in clinical classification tasks on hip MR images, and that using the predictions from the deep-learning model improved the interreader agreement in all pathologies. LEVEL OF EVIDENCE 3 TECHNICAL EFFICACY STAGE: 1 J. Magn. Reson. Imaging 2020;52:1163-1172.

Purpose The purpose of this paper is to assess whether clinicians have an accurate perception of the preventability of their patients’ mortality. Case note review estimates that approximately 5 percent of inpatient deaths are preventable. Design/methodology/approach The design involved in the study is a prospective audit of inpatient mortality in a single NHS hospital trust. The case study includes 979 inpatient mortalities. A number of outcome measures were recorded, including a Likert scale of the preventability of death- and NCEPOD-based grading of care quality. Findings Clinicians assessed only 1.4 percent of deaths as likely to be preventable. This is significantly lower than previously published values (p Research limitations/implications The implications of objective assessment of the preventability of mortality are essential to drive quality improvement in this area. Practical implications There is a wide disparity between independent case note review and clinicians assessing the care of their own patients. This may be due to a “knowledge gap” between reviewers and treating clinicians, or an “objectivity gap” meaning clinicians may not recognize preventability of death of patients under their care. Social implications This study gives some insight into deficiencies in clinical governance processes. Originality/value No similar study has been performed. This has significant implications for the idea of the preventability of mortality.

Group social skills interventions (GSSIs) are a commonly offered treatment for children with high functioning ASD. We critically evaluated GSSI randomised controlled trials for those aged 6-25 years. Our meta-analysis of outcomes emphasised internal validity, thus was restricted to trials that used the parent-report social responsiveness scale (SRS) or the social skills rating system (SSRS). Large positive effect sizes were found for the SRS total score, plus the social communication and restricted interests and repetitive behaviours subscales. The SSRS social skills subscale improved with moderate effect size. Moderator analysis of the SRS showed that GSSIs that include parent-groups, and are of greater duration or intensity, obtained larger effect sizes. We recommend future trials distinguish gains in children's social knowledge from social performance.

Importance: Novel sensitive methods for detection and monitoring of residual disease can improve postoperative risk stratification with implications for patient selection for adjuvant chemotherapy (ACT), ACT duration, intensity of radiologic surveillance, and, ultimately, outcome for patients with colorectal cancer (CRC). Objective: To investigate the association of circulating tumor DNA (ctDNA) with recurrence using longitudinal data from ultradeep sequencing of plasma cell-free DNA in patients with CRC before and after surgery, during and after ACT, and during surveillance. Design, Setting, and Participants: In this prospective, multicenter cohort study, ctDNA was quantified in the preoperative and postoperative settings of stages I to III CRC by personalized multiplex, polymerase chain reaction-based, next-generation sequencing. The study enrolled 130 patients at the surgical departments of Aarhus University Hospital, Randers Hospital, and Herning Hospital in Denmark from May 1, 2014, to January 31, 2017. Plasma samples (n = 829) were collected before surgery, postoperatively at day 30, and every third month for up to 3 years. Main Outcomes and Measures: Outcomes were ctDNA measurement, clinical recurrence, and recurrence-free survival. Results: A total of 130 patients with stages I to III CRC (mean [SD] age, 67.9 [10.1] years; 74 [56.9%] male) were enrolled in the study; 5 patients discontinued participation, leaving 125 patients for analysis. Preoperatively, ctDNA was detectable in 108 of 122 patients (88.5%). After definitive treatment, longitudinal ctDNA analysis identified 14 of 16 relapses (87.5%). At postoperative day 30, ctDNA-positive patients were 7 times more likely to relapse than ctDNA-negative patients (hazard ratio [HR], 7.2; 95% CI, 2.7-19.0; P

Purpose Non-epileptic seizures are paroxysmal events which to an observer resemble epileptic seizures. Proposed risk factors incorporate biopsychosocial aspects including factors in the affected individual. Unexpectedly high rates of autism spectrum disorder (ASD) occurred in the clinical population reported here. Although elevated levels of psychiatric co-morbidity are known to be present in patients with NES, ASD has only been previously described in a single case report. Methods This case series captures rates of ASD in 59 children and young people who were referred to a specialist paediatric mental health service at Great Ormond Street Hospital, London, UK for assessment and treatment of non-epileptic seizures between 2012 and 2016. Results 10/59 (16.9%) of the children and young people with non-epileptic seizures also had ASD, with 5/10 (50%) of these undiagnosed with ASD before referral. Children and young people with ASD were significantly more likely to have tics or attention-deficit hyperactivity disorder than those without ASD. Conclusion ASD may be a common co-morbidity in non-epileptic seizures. Careful clinical assessment with consideration of ASD traits is therefore important in the non-epileptic seizures population. It is beneficial to diagnose ASD early as its presence is likely to require a modified approach to assessment and treatment of non-epileptic seizures. Study of the development of non-epileptic seizures in ASD may suggest hypotheses for the pathogenesis of non-epileptic seizures in the wider population.

PURPOSE Novel sensitive methods for early detection of relapse and for monitoring therapeutic efficacy may have a huge impact on risk stratification, treatment, and ultimately outcome for patients with bladder cancer. We addressed the prognostic and predictive impact of ultra-deep sequencing of cell-free DNA in patients before and after cystectomy and during chemotherapy. PATIENTS AND METHODS We included 68 patients with localized advanced bladder cancer. Patient-specific somatic mutations, identified by whole-exome sequencing, were used to assess circulating tumor DNA (ctDNA) by ultra-deep sequencing (median, 105,000×) of plasma DNA. Plasma samples (n = 656) were procured at diagnosis, during chemotherapy, before cystectomy, and during surveillance. Expression profiling was performed for tumor subtype and immune signature analyses. RESULTS Presence of ctDNA was highly prognostic at diagnosis before chemotherapy (hazard ratio, 29.1; P = .001). After cystectomy, ctDNA analysis correctly identified all patients with metastatic relapse during disease monitoring (100% sensitivity, 98% specificity). A median lead time over radiographic imaging of 96 days was observed. In addition, for high-risk patients (ctDNA positive before or during treatment), the dynamics of ctDNA during chemotherapy was associated with disease recurrence ( P = .023), whereas pathologic downstaging was not. Analysis of tumor-centric biomarkers showed that mutational processes (signature 5) were associated with pathologic downstaging ( P = .024); however, no significant correlation for tumor subtypes, DNA damage response mutations, and other biomarkers was observed. Our results suggest that ctDNA analysis is better associated with treatment efficacy compared with other available methods. CONCLUSION ctDNA assessment for early risk stratification, therapy monitoring, and early relapse detection in bladder cancer is feasible and provides a basis for clinical studies that evaluate early therapeutic interventions.

Background\ud \ud The phenotype of children with XXYY has predominantly been defined by comparison to other sex chromosome aneuploidies trisomies affecting male children; however, the intellectual ability of children with XXYY is lower than children with other sex chromosome aneuploidies trisomies. It is not known to what extent the phenotype identified to date is specific to XXYY, rather than a reflection of lower IQ. This study evaluates the mental health and behaviour of children with XXYY, in comparison to children with intellectual disabilities of heterogeneous genetic origin.\ud \ud \ud Methods\ud \ud Fifteen children with XXYY and 30 controls matched for age (4–14 years), sex and intellectual ability were ascertained from the IMAGINE ID study. IMAGINE ID participants have intellectual disabilities due to genetic anomalies confirmed by National Health Service Regional Genetic Centre laboratories. The mental health and behaviour of participants was examined with the Development and Well‐being Assessment and the Strengths and Difficulties Questionnaire.\ud \ud \ud Results\ud \ud Children with XXYY experienced significantly more frequent and intense temper outbursts than the control group.\ud \ud \ud Conclusion\ud \ud Our results suggest that temper outbursts may be specifically associated with the XXYY phenotype. These problems have a significant impact on the daily lives of boys with XXYY and their families. It is crucial to ensure that families are well supported to manage these difficulties.

The purpose of this study was to evaluate the sensitivity, tumor conspicuity, and image quality of different material decomposition images of phantoms and patients with nearly isodense bone metastases using rapid-kilovoltage-switching dual-energy CT (DECT).Fifty-one semianthropomorphic lumbar spine phantoms embedded with 75 simulated tumors were scanned without and with outer torso-attenuating encasement under the same scan settings. Two radiologists independently reviewed the 70-keV virtual monochromatic and material decomposition images (hydroxyapatite-water, water-hydroxyapatite, cortical bone-water, water-cortical bone). The sensitivity of tumor detection, tumor conspicuity (on a 3-point scale), and image quality (on a 3-point scale) were recorded by two independent readers. McNemar and Wilcoxon signed rank tests were used to compare results between the image reconstructions. Six clinical abdominopelvic DECT scans (three men, three women; mean age, 52 years) with nine nearly isodense lumbar spine tumors missed in the clinical report but confirmed on other scans were also evaluated.The hydroxyapatite-water material decomposition algorithm showed improved sensitivity for isodense lesion detection (without torso phantom encasement, 94% vs 82%, p = 0.031; with torso phantom encasement, 38% vs 18%, p = 0.013), and higher tumor conspicuity scores (p0.0001) compared with 70-keV virtual monoenergetic images. Artifacts were more prevalent with all material decomposition images than with 70-keV virtual monoenergetic images. Similar results were seen in the patient study.Dual-energy CT with hydroxyapatite-water material decomposition may improve the detection of bone marrow metastases, especially for subtle isodense tumors. Further study in prospective clinical scans is warranted.

Antibiotics are majorly used in food animals for growth promotion and prophylactic purposes in public health and environment. The aim of this review is mainly to discuss about the antibiotics usage in poultry, livestock and aquaculture sectors, particularly in India, and the identification of antibiotic resistance in animals, their corresponding antibiotic resistance genes (ARGs) (if investigated) and their dissemination among environmental compartments in various parts of the country. It also discusses about the classification and mechanism of action of different antibiotics. It reports the risks, benefits, ARGs development mechanisms from food animals to humans and to the environment. Most of the current studies are done in the medical field on regulating/restricting antibiotic usage and tracking the propagation of ARGs in bacterial samples of sick patients and also report the identification of antibiotics and ARGs in wastewater treatment plant effluents across various countries. This study mainly reviews the evolution and transportation of ARGs in detail for Indian scenario.

Background There are few population-based cohort studies of the emergence, development, and persistence of mental health problems in sexual minorities compared with heterosexuals. We compared trajectories of depressive symptoms in sexual-minority adolescents and heterosexual adolescents from when they were aged 10 to 21 years, and examined self-harm at ages 16 and 21 years. Methods The study included 4828 adolescents born between April 1, 1991, and Dec 31, 1992, from the Avon Longitudinal Study of Parents and Children birth cohort (Bristol, UK) who reported their sexual orientation when aged 16 years. Depressive symptoms were assessed with the short Mood and Feelings Questionnaire at seven timepoints between ages 10 and 21 years. A self-harm questionnaire was completed at ages 16 and 21 years. Analyses were linear multilevel models with growth curves (depressive symptoms), logistic multilevel models (self-harm in the previous year at ages 16 and 21 years), and multinomial regression (lifetime self-harm with and without suicidal intent at age 21 years). Findings At age 10, depressive symptoms were higher in sexual minorities than in heterosexuals and increased with age to a larger extent. Depressive symptoms increased at each timepoint by 0·31 points in hetereosexuals, and by 0·49 points in sexual minorities. Sexual-minority adolescents were more likely than heterosexual adolescents to report self-harm in the previous year at ages 16 and 21 years, with no evidence that this estimate decreased with age. At aged 21, sexual minorities were more likely to report lifetime self-harm (ie, on at least one previous occasion) with suicidal intent than heterosexuals. Interpretation Mental health disparities between heterosexuals and sexual minorities are present early in adolescence and increase throughout the school years, persisting to young adulthood. Prevention of these mental health problems and early intervention must be a priority.

Anterior cruciate ligament (ACL) tears are common injuries that if left untreated can result in chronic instability, cartilage damage, meniscal tears, and ligamentous injuries, eventually leading to early osteoarthritis. ACL reconstruction surgeries are therefore increasingly being performed. Despite the fact that most patients achieve excellent postoperative results, patients can present with recurrent instability and pain. These patients often undergo imaging with radiographs, magnetic resonance imaging, and/or computed tomography. An understanding of the imaging appearance of the normal ACL reconstruction and common causes of failure is therefore essential for the interpreting radiologist. This article reviews surgical techniques for ACL reconstruction, highlighting recent technical advances, the normal imaging appearance after ACL reconstruction, etiologies for reconstruction failure, and the diagnosis of these with the aid of imaging.

Conversational user interfaces (CUIs) are rapidly evolving towards being ubiquitous as human-machine interfaces. Often, CUI backends are powered by a combination of human and machine intelligence, to address queries efficiently. Depending on the type of conversation issue, human-to-human conversations in CUIs (i.e. a human end-user conversing with the human in the CUI backend) could involve varying amounts of emotional content. While some of these emotions could be expressed through the conversation, others are experienced internally within the individual. Understanding the relationship between these two emotion modalities in the end-user could help to analyze and address the conversation issue better. Towards this, we propose an emotion analytic metric that can estimate experienced emotions based on its knowledge about expressed emotions in a user. Our findings point to the possibility of augmenting CUIs with an algorithmically guided emotional sense, which would help in having more effective conversations with end-users.

Background Circulating tumor DNA (ctDNA) analysis is an emerging field for diagnosis, monitoring of treatment efficacy and detection of disease recurrence in various cancers. In bladder cancer, previous work has demonstrated prognostic value of ctDNA for early stage cancers and early detection of recurrence following radical cystectomy (CX), however more extensive investigation of the potential impact of ctDNA analysis on clinical decision making remains to be carried out. Methods A total of 68 patients with localized advanced bladder cancer to be treated with neoadjuvant chemotherapy (NAC) and CX were prospectively included. We performed RNA-Seq to identify RNA subtypes and whole exome sequencing to identify somatic mutations for ctDNA analysis. Based on allele frequency and sequence context, 16 somatic mutations were selected for each patient for multiplex PCR and subsequent ultra-deep sequencing (median coverage of 114,000x). The sample-level analytical sensitivity was determined to be >95% at 0.01% ctDNA concentration level when at least 2/16 mutations were detected. The protocol was applied to detect ctDNA in 618 blood samples procured at diagnosis, during NAC, before CX and during surveillance following CX. Results The presence of ctDNA was highly prognostic already at diagnosis before initiation of NAC (HR=31.7, p=0.001). Analysis of ctDNA dynamics during NAC revealed that clearance of ctDNA was associated with pathological downstaging (≤TaN0 at CX) and reduced disease recurrence. Conversely, continually detectable ctDNA during NAC was associated with lack of pathological downstaging and later disease recurrence (p=0.023). Our results suggest that ctDNA dynamics during NAC may offer superior predictive value compared to clinical parameters and tumor centric molecular markers such as DNA damage response mutations and RNA subtypes. Following CX, ctDNA analysis identified 92% of metastatic relapse (100% specificity) during disease monitoring (100% positive- and 98% negative predictive value). The positive lead-time over radiographic imaging was 100 days on average (range: -17-245 days). Conclusions ctDNA analysis of blood samples procured throughout the disease course of patients with bladder cancer demonstrates novel evidence of early risk stratification and monitoring of treatment efficacy, which adds to the already strong evidence of ctDNA-based recurrence detection. Collectively, this paves the way for novel ctDNA-based clinical trials. Citation Format: Emil Christensen, Karin Birkenkamp-Demtröder, Himanshu Sethi, Svetlana Shchegrova, Raheleh Salari, Iver Nordentoft, Hsin-Ta Wu, Michael Knudsen, Philippe Lamy, Sia V. Lindskrog, Ann Taber, Mustafa Balcioglu, Søren Vang, Zoe Assaf, Shruti Sharma, Antony S. Tin, Ramya Srinivasan, Dina Hafez, Thomas Reinert, Samantha Navarro, Alexander Olson, Rosie Ram, Scott Dashner, Matthew Rabinowitz, Paul Billings, Styrmir Sigurjonsson, Claus L. Andersen, Ryan Swenerton, Alexey Aleshin, Bernhard G. Zimmermann, Mads Agerbæk, Cheng-Ho J. Lin, Jørgen B. Jensen, Lars Dyrskjøt. Early detection of metastatic relapse and monitoring of therapeutic efficacy by ultra-deep sequencing of plasma cell-free DNA in patients with urothelial bladder carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 913.

The first metatarsophalangeal joint and hallucal-sesamoid complex are critical structures in weightbearing and susceptible to several pathologies including turf toe, sesamoiditis, degenerative or inflammatory arthritides, infection, and avascular necrosis. This review article summarizes the complex anatomy of the region, covers common pathologies while clarifying terms such as turf toe and sesamoiditis, reviews imaging techniques, and discusses management.

Setting: A specialist multi-disciplinary outpatient eating disorders centre in Australia. Patients: Adolescents aged 12-18 years with a diagnosis of anorexia nervosa (AN) or partial AN based on DSM-IV criteria (excluding amenorrhoea) living with at least one parent. Those who presented with severe medical or psychiatric comorbidity were excluded. Those who had previously received family-based treatment (FBT) were also excluded. Intervention: Manualised outpatient treatment delivered as 18 sessions over 6 months. FBT which included the entire family and the adolescent in treatment sessions was compared with PFT. This involved sessions with the same focus as FBT but attended by the parents only, without the adolescent or siblings present. Outcomes: Remission was defined as increase in weight to >95% median BMI at the end of treatment and Global Eating Disorder Examination (EDE) within 1 SD of community norms. Follow-up period: Participants were …

markdownabstractIntroduction: Femoroacetabular impingement syndrome is a common cause of hip-related pain in active young adults. It comprises a triad of imaging findings, symptoms and signs, and is usually characterised by extra bone formation at the femoral head-neck junction known as ‘cam morphology’. Cam morphology is theorised to create hip impingement in hip flexion activities, place stress on hip joint structures, and increase the risk of hip osteoarthritis over time.

According to World Health Organization statistics of 2011, infectious diseases remain in the top five causes of mortality worldwide. However, despite sophisticated research tools for microbial detection, rapid and accurate molecular diagnostics for identification of infection in humans have not been extensively adopted. Time-consuming culture-based methods remain to the forefront of clinical microbial detection. The 16S rRNA gene, a molecular marker for identification of bacterial species, is ubiquitous to members of this domain and, thanks to ever-expanding databases of sequence information, a useful tool for bacterial identification. In this study, we assembled an extensive repository of clinical isolates (n = 617), representing 30 medically important pathogenic species and originally identified using traditional culture-based or non-16S molecular methods. This strain repository was used to systematically evaluate the ability of 16S rRNA for species level identification. To enable the most accurate species level classification based on the paucity of sequence data accumulated in public databases, we built a Naïve Bayes classifier representing a diverse set of high-quality sequences from medically important bacterial organisms. We show that for species identification, a model-based approach is superior to an alignment based method. Overall, between 16S gene based and clinical identities, our study shows a genus-level concordance rate of 96% and a species-level concordance rate of 87.5%. We point to multiple cases of probable clinical misidentification with traditional culture based identification across a wide range of gram-negative rods and gram-positive cocci as well as common gram-negative cocci.