Follicular helper- and peripheral helper-like T cells drive autoimmune disease in human immune system mice.

Human immune system (HIS) mice constructed in various ways are widely used for investigations of human immune responses to pathogens, transplants and immunotherapies. In HIS mice that generate T cells de novo from hematopoietic progenitors, T cell-dependent multisystem autoimmune disease occurs, most rapidly when the human T cells develop in the native NOD.Cg- Prkdc scid Il2rg tm1Wjl (NSG) mouse thymus, where negative selection is abnormal. Disease develops very late when human T cells develop in human fetal thymus grafts, where robust negative selection is observed. We demonstrate here that PD-1 + CD4 + peripheral (Tph) helper-like and follicular (Tfh) helper-like T cells developing in HIS mice can induce autoimmune disease. Tfh-like cells were more prominent in HIS mice with a mouse thymus, in which the highest levels of IgG were detected in plasma, compared to those with a human thymus. While circulating IgG and IgM antibodies were autoreactive to multiple mouse antigens, in vivo depletion of B cells and antibodies did not delay the development of autoimmune disease. Conversely, adoptive transfer of enriched Tfh- or Tph-like cells induced disease and autoimmunity-associated B cell phenotypes in recipient mice containing autologous human APCs without T cells. T cells from mice with a human thymus expanded and induced disease more rapidly than those originating in a murine thymus, implicating HLA-restricted T cell-APC interactions in this process. Since Tfh, Tph, autoantibodies and LIP have all been implicated in various forms of human autoimmune disease, the observations here provide a platform for the further dissection of human autoimmune disease mechanisms and therapies.

Population Pharmacokinetics of Single Bolus Dose Fentanyl in Obese Children.

BACKGROUND: Childhood obesity is a significant problem. Obesity may alter the pharmacokinetics (PKs) of medications. Fentanyl is commonly used for procedural sedation, but there is a paucity of bolus dose fentanyl PK data in obese children. Better understanding of fentanyl PK in obese children would facilitate dosing recommendations. We conducted a study involving children with and without obesity to assess the potential differences in bolus dose fentanyl PK between the 2 groups. METHODS: We enrolled children 2 to 12 years of age with and without obesity, defined as >95th percentile body mass index (BMI) for age and sex, undergoing elective tonsillectomy ± adenoidectomy. After induction, subjects had 2 intravenous (IV) lines placed in 2 different extremities: 1 for medications and IV fluids and 1 for obtaining blood aliquots for fentanyl concentration analysis. After administration of 1 mcg/kg of fentanyl based on total body weight (TBW), blood sample collections for fentanyl concentration analysis were attempted at 5, 15, 30, 60, 90, and 120 minutes. Five-minute fentanyl concentrations were compared between obese and nonobese cohorts. Population PK analysis to examine the differences between obese and nonobese children was performed and included various body size descriptors, such as TBW, BMI, and fat-free mass (FFM), to examine their influence on model parameters. RESULTS: Half of the 30 subjects were obese. Mean fentanyl concentrations at 5 minutes were 0.53 ng/mL for the nonobese group and 0.88 ng/mL for the obese group, difference 0.35 ng/mL (95% CI, 0.08-0.61 ng/mL; P = .01). Population PK analysis showed that FFM was a significant covariate for the central volume of distribution. The potential clinical effect of an IV bolus dose of fentanyl based on TBW versus FFM in an obese child was assessed in a simulation using our model. 1 mcg/kg fentanyl dose based on TBW resulted in an approximately 60% higher peak fentanyl effect site concentration than dosing based on FFM. CONCLUSIONS: Our data demonstrated higher peak plasma fentanyl concentrations in obese compared to nonobese subjects. Population PK analysis found that FFM was a significant covariate for the central volume of distribution. Model simulation showed dosing of fentanyl in obese children based on TBW resulted in significantly higher peak concentrations than dosing based on FFM. Based on this modeling and the known concentration-effect relationship between fentanyl and adverse effects, our results suggest that bolus dosing of fentanyl in obese children should be based on FFM rather than TBW, particularly for procedures of short duration.

Sintomas Cardiopulmonares Pós-COVID-19: Preditores e Características de Imagem de Pacientes após a Alta Hospitalar / Post-COVID-19 Cardiopulmonary Symptoms: Predictors and Imaging Features in Patients after Hospital Discharge

Resumo Fundamento A maioria da evidência sobre o impacto da síndrome COVID pós-aguda (PACS, do inglês, post-acute COVID-19 syndrome) descreve sintomas individuais sem correlacioná-los com exames de imagens. Objetivos Avaliar sintomas cardiopulmonares, seus preditores e imagens relacionadas em pacientes com COVID-19 após alta hospitalar. Métodos Pacientes consecutivos, que sobreviveram à COVID-19, foram contatados 90 dias após a alta hospitalar. A equipe de desfechos clínicos (cega quanto aos dados durante a internação) elaborou um questionário estruturado avaliando sintomas e estado clínico. Uma análise multivariada foi realizada abordando a evolução da COVID-19, comorbidades, ansiedade, depressão, e estresse pós-traumático durante a internação, e reabilitação cardíaca após a alta. O nível de significância usado nas análises foi de 5%. Resultados Foram incluídos 480 pacientes (idade 59±14 anos, 67,5% do sexo masculino) que receberam alta hospitalar por COVID-19; 22,3% necessitaram de ventilação mecânica. A prevalência de pacientes com sintomas cardiopulmonares relacionados à PACS (dispneia, cansaço/fadiga, tosse e desconforto no peito) foi de 16,3%. Vários parâmetros de tomografia computadorizada do tórax e de ecocardiograma foram similares entre os pacientes com e sem sintomas cardiopulmonares. A análise multivariada mostrou que sintomas cardiopulmonares foram relacionados de maneira independente com sexo feminino (OR 3,023; IC95% 1,319-6,929), trombose venosa profunda durante a internação (OR 13,689; IC95% 1,069-175,304), nível elevado de troponina (OR 1,355; IC95% 1,048-1,751) e de proteína C reativa durante a internação (OR 1,060; IC95% 1,023-1,097) e depressão (OR 6,110; IC95% 2,254-16,558). Conclusão Os sintomas cardiopulmonares relacionados à PACS 90 dias após a alta hospitalar são comuns e multifatoriais. Além dos marcadores trombóticos, inflamatórios e de lesão miocárdica durante a internação, sexo feminino e depressão foram associados independentemente com sintomas cardiopulmonares relacionados à PACS. Esses resultados destacaram a necessidade de uma abordagem multifacetada direcionada a pacientes susceptíveis.

Abstract Background Most of the evidence about the impact of the post-acute COVID-19 Syndrome (PACS) reports individual symptoms without correlations with related imaging. Objectives To evaluate cardiopulmonary symptoms, their predictors and related images in COVID-19 patients discharged from hospital. Methods Consecutive patients who survived COVID-19 were contacted 90 days after discharge. The Clinic Outcome Team structured a questionnaire evaluating symptoms and clinical status (blinded for hospitalization data). A multivariate analysis was performed to address the course of COVID-19, comorbidities, anxiety, depression, and post-traumatic stress during hospitalization, and cardiac rehabilitation after discharge. The significance level was set at 5%. Results A total of 480 discharged patients with COVID-19 (age: 59±14 years, 67.5% males) were included; 22.3% required mechanical ventilation. The prevalence of patients with PACS-related cardiopulmonary symptoms (dyspnea, tiredness/fatigue, cough, and chest discomfort) was 16.3%. Several parameters of chest computed tomography and echocardiogram were similar in patients with and without cardiopulmonary symptoms. The multivariate analysis showed that PACS-related cardiopulmonary-symptoms were independently related to female sex (OR 3.023; 95% CI 1.319-6.929), in-hospital deep venous thrombosis (OR 13.689; 95% CI 1.069-175.304), elevated troponin I (OR 1.355; 95% CI 1.048-1.751) and C-reactive protein during hospitalization (OR 1.060; 95% CI 1.023-1.097) and depression (OR 6.110; 95% CI 2.254-16.558). Conclusion PACS-related cardiopulmonary symptoms 90 days post-discharge are common and multifactorial. Beyond thrombotic and markers of inflammation/myocardial injury during hospitalization, female sex and depression were independently associated with cardiopulmonary-related PACS. These results highlighted the need for a multifaceted approach targeting susceptible patients.

Human stem cell-derived thymic epithelial cells enhance human T-cell development in a xenogeneic thymus.

BACKGROUND: Generation of thymic tissue from pluripotent stem cells would provide therapies for acquired and congenital thymic insufficiency states. OBJECTIVES: This study aimed to generate human thymic epithelial progenitors from human embryonic stem cells (hES-TEPs) and to assess their thymopoietic function in vivo. METHODS: This study differentiated hES-TEPs by mimicking developmental queues with FGF8, retinoic acid, SHH, Noggin, and BMP4. Their function was assessed in reaggregate cellular grafts under the kidney capsule and in hybrid thymi by incorporating them into swine thymus (SwTHY) grafts implanted under the kidney capsules of immunodeficient mice that received human hematopoietic stem and progenitor cells (hHSPCs) intravenously. RESULTS: Cultured hES-TEPs expressed FOXN1 and formed colonies expressing EPCAM and both cortical and medullary thymic epithelial cell markers. In thymectomized immunodeficient mice receiving hHSPCs, hES-TEPs mixed with human thymic mesenchymal cells supported human T-cell development. Hypothesizing that support from non-epithelial thymic cells might allow long-term function of hES-TEPs, the investigators injected them into SwTHY tissue, which supports human thymopoiesis in NOD severe combined immunodeficiency IL2Rγnull mice receiving hHSPCs. hES-TEPs integrated into SwTHY grafts, enhanced human thymopoiesis, and increased peripheral CD4+ naive T-cell reconstitution. CONCLUSIONS: This study has developed and demonstrated in vivo thymopoietic function of hES-TEPs generated with a novel differentiation protocol. The SwTHY hybrid thymus model demonstrates beneficial effects on human thymocyte development of hES-TEPs maturing in the context of a supportive thymic structure.

Mechanisms of differential desensitization of metabotropic glutamate receptors.

G protein-coupled receptors (GPCRs) interact with intracellular transducers to control both signal initiation and desensitization, but the distinct mechanisms that control the regulation of different GPCR subtypes are unclear. Here we use fluorescence imaging and electrophysiology to examine the metabotropic glutamate receptor (mGluR) family. We find distinct properties across subtypes in both rapid desensitization and internalization, with striking differences between the group II mGluRs. mGluR3, but not mGluR2, undergoes glutamate-dependent rapid desensitization, internalization, trafficking, and recycling. We map differences between mGluRs to variable Ser/Thr-rich sequences in the C-terminal domain (CTD) that control interaction with both GPCR kinases and ß-arrestins. Finally, we identify a cancer-associated mutation, G848E, within the mGluR3 CTD that enhances ß-arrestin coupling and internalization, enabling an analysis of mGluR3 ß-arrestin-coupling properties and revealing biased variants. Together, this work provides a framework for understanding the distinct regulation and functional roles of mGluR subtypes.

Whole-Proteome Differential Screening Identifies Novel Vaccine Candidates for Schistosomiasis japonica.

Schistosomiasis remains a leading cause of chronic morbidity in endemic regions despite decades of widespread mass chemotherapy with praziquantel. Using our whole proteome differential screening approach, and plasma and epidemiologic data from a longitudinal cohort of individuals living in a Schistosoma japonicum-endemic region of the Philippines, we interrogated the parasite proteome to identify novel vaccine candidates for Schistosoma japonicum. We identified 16 parasite genes which encoded proteins that were recognized by immunoglobulin G or immunoglobulin E antibodies in the plasma of individuals who had developed resistance to reinfection, but were not recognized by antibodies in the plasma of individuals who remained susceptible to reinfection. Antibody levels to Sj6-8 and Sj4-1 measured in the entire cohort (N = 505) 1 month after praziquantel treatment were associated with significantly decreased risk of reinfection and lower intensity of reinfection over 18 months of follow-up.

Role of the thymus in spontaneous development of a multi-organ autoimmune disease in human immune system mice.

We evaluated the role of the thymus in development of multi-organ autoimmunity in human immune system (HIS) mice. T cells were essential for disease development and the same T cell clones with varying phenotypes infiltrated multiple tissues. De novo-generated hematopoietic stem cell (HSC)-derived T cells were the major disease drivers, though thymocytes pre-existing in grafted human thymi contributed if not first depleted. HIS mice with a native mouse thymus developed disease earlier than thymectomized mice with a thymocyte-depleted human thymus graft. Defective structure in the native mouse thymus was associated with impaired negative selection of thymocytes expressing a transgenic TCR recognizing a self-antigen. Disease developed without direct recognition of antigens on recipient mouse MHC. While human thymus grafts had normal structure and negative selection, failure to tolerize human T cells recognizing mouse antigens presented on HLA molecules may explain eventual disease development. These new insights have implications for human autoimmunity and suggest methods of avoiding autoimmunity in next-generation HIS mice.

Targeting dual signalling pathways in concert with immune checkpoints for the treatment of pancreatic cancer.

OBJECTIVE: This study exploits the intersection between molecular-targeted therapies and immune-checkpoint inhibition to define new means to treat pancreatic cancer. DESIGN: Patient-derived cell lines and xenograft models were used to define the response to CDK4/6 and MEK inhibition in the tumour compartment. Impacts relative to immunotherapy were performed using subcutaneous and orthotopic syngeneic models. Single-cell RNA sequencing and multispectral imaging were employed to delineate effects on the immunological milieu in the tumour microenvironment. RESULTS: We found that combination treatment with MEK and CDK4/6 inhibitors was effective across a broad range of PDX models in delaying tumour progression. These effects were associated with stable cell-cycle arrest, as well as the induction of multiple genes associated with interferon response and antigen presentation in an RB-dependent fashion. Using single-cell sequencing and complementary approaches, we found that the combination of CDK4/6 and MEK inhibition had a significant impact on increasing T-cell infiltration and altering myeloid populations, while potently cooperating with immune checkpoint inhibitors. CONCLUSIONS: Together, these data indicate that there are canonical and non-canonical features of CDK4/6 and MEK inhibition that impact on the tumour and immune microenvironment. This combination-targeted treatment can promote robust tumour control in combination with immune checkpoint inhibitor therapy.

Chemotherapy impacts on the cellular response to CDK4/6 inhibition: distinct mechanisms of interaction and efficacy in models of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a therapy recalcitrant disease characterized by the aberrations in multiple genes that drive pathogenesis and limit therapeutic response. While CDK4/6 represents a downstream target of both KRAS mutation and loss of the CDKN2A tumor suppressor in PDAC, clinical and preclinical studies indicate that pharmacological CDK4/6 inhibitors are only modestly effective. Since chemotherapy represents the established backbone of PDAC treatment we evaluated the interaction of CDK4/6 inhibitors with gemcitabine and taxanes that are employed in the treatment of PDAC. Herein, we demonstrate that the difference in mechanisms of actions of chemotherapeutic agents elicit distinct effects on the cellular response to CDK4/6 inhibition. Gemcitabine largely ablates the function of CDK4/6 inhibition in S-phase arrested cells when administered contemporaneously; although, when cells recover from S-phase block they exhibit sensitivity to CDK4/6 inhibition. In contrast, pharmacological inhibition of CDK4/6 yields a cooperative cytostatic effect in combination with docetaxel and prevents adaptation and cell cycle re-entry, which is a common basis for resistance to such agents. Importantly, using organoid and PDX models we could confirm the cooperative effects between chemotherapy and CDK4/6 inhibition in vivo. These data indicate that the combination of cytotoxic and cytostatic agents could represent an important modality in those tumor types that are relatively resistant to CDK4/6 inhibitors.

Does Tonsillectomy Increase Obesity Risk in Children with Down Syndrome?

OBJECTIVES: To examine weight changes relative to surgical success in children with Down syndrome and obstructive sleep apnea (OSA). STUDY DESIGN: Retrospective chart review of children with Down syndrome undergoing tonsillectomy from 2005 to 2016 for OSA at a tertiary care children's hospital. Only patients with pre-and postoperative polysomnogram within 6 months of tonsillectomy were included. Demographics, weight, height, and polysomnogram data were collected. Body mass index (BMI), expressed as a percentage of the 95th percentile (%BMIp95), was calculated for 24 months prior to and following surgery. Pre-and postoperative OSA severity were also recorded. The postoperative obstructive/hypopnea index identified subjects with resolution of obstruction (obstructive/hypopnea index <2 events/hour) or persistent mild/moderate/severe obstructive apnea. Regression analyses were used to compare %BMIp95 pre- and post-tonsillectomy with %BMIp95 by OSA status following tonsillectomy. RESULTS: A total of 78 patients with Down syndrome whose mean age was 5.29 years at time of tonsillectomy were identified. There was no difference between best-fit curves of %BMI p95 pre-and post-tonsillectomy. There was no difference between best-fit curves of %BMI p95 in patients who saw resolution of OSA after tonsillectomy vs patients with residual OSA. CONCLUSIONS: Tonsillectomy neither alters the BMI trajectory of children with Down syndrome, nor changes differentially the risk for obesity in children whose OSA did or did not resolve after surgery.

Pediatric Obstructive Sleep-Disordered Breathing: Updated Polysomnography Practice Patterns.

OBJECTIVE: To assess the current practice patterns of pediatric otolaryngologists in managing obstructive sleep-disordered breathing 6 years following the 2011 publication of the clinical practice guideline "Polysomnography for Sleep-Disordered Breathing prior to Tonsillectomy in Children." STUDY DESIGN: Cross-sectional survey. SETTING: American Society of Pediatric Otolaryngology (ASPO) members. SUBJECTS AND METHODS: An electronic survey to assess ASPO members' adherence to polysomnography guidelines prior to tonsillectomy. RESULTS: Forty percent (170 of 427) of ASPO members completed the survey, with 73% in academic practice and 27% in private practice. Snoring represented, on average, 48% of the respondents' practices. The percentage of respondents who requested a polysomnogram prior to tonsillectomy ≥90% of the time was 55% (n = 94) for Down syndrome, 41% (n = 69) for a child <2 years old, and 29% (n = 49) for obese children. A total of 109 (73%) and 112 (75%) respondents admit at least 90% of the time for a child with Down syndrome and for a child <3 years of age, respectively, but only 52 (35%) have a similar practice for an obese child. Only 37% adhere to the inpatient admission recommendation for children with documented obstructive sleep apnea on polysomnogram. CONCLUSION: The current polysomnogram practice patterns for responding pediatric otolaryngologists are not aligned with the clinical practice guideline of the American Academy of Otolaryngology-Head and Neck Surgery Foundation. The threshold for overnight observation when a preoperative polysomnogram has not been performed may be too low. A campaign is necessary to educate clinicians who take care of children with obstructive sleep-disordered breathing and to obtain more evidence to further define best practice.

Cell cycle plasticity driven by MTOR signaling: integral resistance to CDK4/6 inhibition in patient-derived models of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC), like many KRAS-driven tumors, preferentially loses CDKN2A that encodes an endogenous CDK4/6 inhibitor to bypass the RB-mediated cell cycle suppression. Analysis of a panel of patient-derived cell lines and matched xenografts indicated that many pancreatic cancers have intrinsic resistance to CDK4/6 inhibition that is not due to any established mechanism or published biomarker. Rather, there is a KRAS-dependent rapid adaptive response that leads to the upregulation of cyclin proteins, which participate in functional complexes to mediate resistance. In vivo, the degree of response is associated with the suppression of a gene expression signature that is strongly prognostic in pancreatic cancer. Resistance is associated with an adaptive gene expression signature that is common to multiple kinase inhibitors, but is attenuated with MTOR inhibitors. Combination treatment with MTOR and CDK4/6 inhibitors had potent activity across a large number of patient-derived models of PDAC underscoring the potential clinical efficacy.

Dornase Alfa Ototoxic Effects in Animals and Efficacy in the Treatment of Clogged Tympanostomy Tubes in Children: A Preclinical Study and a Randomized Clinical Trial.

Importance: Many treatments for clogged tympanostomy tubes (TTs) have been proposed, but none have met scientific rigor for safety and efficacy, including the popular empirical use of ototopical antibiotic drops. Dornase alfa, a recombinant molecule with the unique property of cleaving DNA, may be ideal in treating clogged TTs because both middle-ear effusion and the plug are abundant with DNA. Objective: To investigate the ototoxic effects of dornase alfa in a chinchilla model and its efficacy in a clinical trial in children with clogged TTs. Design, Setting, and Participants: The safety profiles of dornase alfa (full-strength and 1:10 strength) were evaluated in chinchilla middle ears using serial auditory brainstem response. The efficacy of ototopical dornase alfa (full-strength) was evaluated in children with clogged TTs in a prospective, single-blind randomized clinical trial. The animal study included 21 chinchillas and was conducted at Loma Linda University, Loma Linda, California, and the clinical trial was conducted at Children's Hospital Colorado, Aurora. A total of 40 children (50 ears with tubes) were enrolled. Interventions: In the animal study, chinchillas were assigned to 3 groups: controls (saline), full-strength dornase alfa, or 1:10 dornase alfa dilution. Children were randomly assigned to receive either topical dornase alfa or ofloxacin for clogged TT, 5 drops each ear twice a day for 7 days. Main Outcomes and Measures: Animal study: Auditory brainstem responses. Randomized trial of children participants: The primary outcome was patency of TT at day 14 assessed by otoscopy and tympanometry. Results: The chinchilla study showed similar auditory brainstem response degradation during a 6-hour period between the control (n = 5) and treatment groups (n = 21). In the clinical trial, a total of 40 clogged TTs (in 33 children, including 25 boys [76%]; mean age, 4.3 years; median [range] age, 3.4 [1.0-14.3] years) were analyzed. The number of unclogged TTs was higher in the dornase alfa group (13 [59%]) compared with the ofloxacin group (8 [44%]), with a difference of 15% (odds ratio, 1.8; 95% CI, 0.54-6.72). Conclusions and Relevance: The chinchilla model suggests that dornase alfa is likely nonototoxic. The pilot clinical trial failed to show efficacy of dornase alfa to unclog TTs. With the difference seen between the treatment groups, a sample size estimate could be calculated for a future large-scale trial. Trial Registration: ClinicalTrials.gov identifier: NCT00419380.

Accuracy of Parental Perception of Nighttime Breathing in Children with Down Syndrome.

Objective In 2011, the American Academy of Pediatrics published a guideline for children with Down syndrome (DS), recommending a polysomnogram (PSG) by age 4 years regardless of symptoms. Their rationale was based on 2 publications with small cohorts, where at least 50% of the children had no obstructive sleep apnea (OSA) symptoms but their PSG results were abnormal. The American Academy of Otolaryngology-Head and Neck Surgery Foundation published a clinical practice guideline recommending PSG prior to adenotonsillectomy for these children. This study aimed to assess parents' accuracy of their children's breathing patterns as compared with PSGs in a larger cohort of children with DS. Study Design Case series with chart review. Setting Tertiary care academic pediatric hospital. Subjects and Methods Sleep intake forms assessing frequency of parent-observed apnea, snoring, and restless sleep were analyzed. None of the children had a previous tonsillectomy. Two groups were analyzed according to symptoms: infrequent (<3 nights per week on all questions answered) and frequent (≥6 nights per week on at least 1 question). OSA severity was categorized as follows: normal, <2 events per hour; mild, 2 to 4.9; moderate, 5 to 9.9; and severe, ≥10. Results A total of 113 children met inclusion criteria: 34% (n = 38) had infrequent symptoms, and 66% (n = 75) had frequent symptoms. Parents were unable to predict the presence or absence of OSA by nighttime symptoms ( P = .60). The risk of OSA for children with frequent symptoms versus those with infrequent symptoms was 1.04 (95% CI, 0.89-1.3). Conclusion Parents of DS children are unable to predict the presence or absence of OSA by nighttime symptoms, nor are they able to determine its severity.

Composite analysis of immunological and metabolic markers defines novel subtypes of triple negative breast cancer.

Cancer biology is influenced by the tumor microenvironment, which impacts disease prognosis and therapeutic interventions. The inter-relationship of tumor-infiltrating lymphocytes, immune response regulators, and a glycolytic tumor environment was evaluated in a cohort of 183 largely consecutive patients with triple negative breast cancer diagnosis. High levels of tumor-infiltrating lymphocytes were associated with improved survival of triple negative breast cancer cases. However, elevated levels of PD-L1, CD163, and FOXP3 were individually associated with significantly decreased overall survival. These three determinants were significantly correlated, and could serve to differentiate the prognostic significance of tumor-infiltrating lymphocytes. Interestingly, a glycolytic tumor environment, as determined by the expression of MCT4 in the tumor stroma, was associated with the immune evasive environment and poor prognosis. Clustering of all markers defined four distinct triple negative breast cancer subtypes that harbored prognostic significance in multivariate analysis. Immune and metabolic markers stratified triple negative breast cancer into subtypes that have prognostic significance and implications for therapies targeting immune checkpoints and tumor metabolism.

Success of Tonsillectomy for Obstructive Sleep Apnea in Children With Down Syndrome.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is common in children with Down syndrome (DS) and associated with significant morbidity. In the current study we examined polysomnographic outcomes of children with DS who underwent tonsillectomy. METHODS: A retrospective chart review of children with DS who underwent a tonsillectomy between 2009-2015 was performed. All children had either a concurrent adenoidectomy or had previously underwent an adenoidectomy. Children with preoperative and postoperative polysomnograms within 6 months of surgery were included in the analysis. Preoperative OSA severity was categorized by obstructive apnea-hypopnea index (OAHI) as follows: mild = 1.5-4.9 events/h; moderate = 5-9.9 events/h; severe ≥ 10 events/h. RESULTS: Seventy-five children with DS met inclusion criteria. The cohort included 41 males and 34 females with mean age of 5.1 years (± 3.6 years), range of 0.51-16.60 years. Preoperative OSA severity was as follows, mild = 8/75; moderate = 16/75; severe = 51/75. Cure rates varied depending on definition: 12% for OAHI < 1 event/h and 21% for OAHI < 2 events/h. 48% had residual OAHI < 5 events/h. On postoperative PSG 16/75 saw resolution (OAHI < 2) in OSA; mild = 21/75; moderate = 20/75; severe = 18/75. 48% moderate/severe patients saw conversion to mild or cure. Overall, tonsillectomy resulted in significant improvements in multiple respiratory parameters, including OAHI (OAHI; 21.3 ± 19.7 to 8.0 ± 8.1, P < .001), percent sleep time with oxygen saturations < 90% (19.0 ± 25.0 to 6.1 ± 10.1, P < .001), and percent sleep time with end-tidal carbon dioxide above 50 mmHg (7.7 ± 18.0 to 1.8 ± 6.6, P = .001). Average asleep oxygen saturation was associated with postoperative OSA severity. CONCLUSIONS: Children with DS and OSA who undergo tonsillectomy experience improvements in both respiratory event frequency and gas exchange but approximately half still have moderate to severe residual OSA.

The current state of pediatric drug-induced sleep endoscopy.

OBJECTIVES/HYPOTHESIS: The purpose of this investigation was to assess current drug-induced sleep endoscopy (DISE) practice patterns at centers that have published on the technique, to identify areas of agreement, and to identify areas of disagreement that may represent opportunities for improvement and standardization. STUDY DESIGN: Multi-institutional survey. METHODS: A survey was designed in two phases to evaluate preoperative assessment, intraoperative performance, and postoperative management of patients undergoing DISE. The survey was constructed iteratively in consultation with the all of the coauthors, each selected as an expert owing to their previous publication of one or more articles pertaining to pediatric DISE. In the first phase of survey creation, each expert was asked to provide narrative answers to questions pertaining to DISE. These responses served as the basis for a second survey. This second survey was then administered to all pediatric otolaryngologists at each respective institution. RESULTS: Overall, there was a low rate of agreement (33%) among the respondents; however, there was substantial agreement within institution, particularly for the use of anesthetic medications, the use of cine magnetic resonance imaging, and performance of bronchoscopy along with DISE. There was strong agreement among all respondents for performing DISE in a child with severe obstructive sleep apnea following adenotonsillectomy, regardless of comorbidities. CONCLUSION: This multi-institutional survey demonstrated a lack of consensus between experts and multiple opportunities for improvement. In general, there was agreement regarding the workup prior to DISE performance and the endoscopic protocol but disagreement regarding anesthetic protocol and management decisions. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:266-272, 2017.

A Pediatric Grading Scale for Lingual Tonsil Hypertrophy.

Lingual tonsil hypertrophy (LTH) is a common finding for children with residual obstructive sleep apnea (OSA) following an adenotonsillectomy. Secondary to the significant morbidity associated with OSA, identification and treatment of residual OSA are paramount. A dedicated LTH grading scale for children does not exist. The current adult LTH scale is impractical for children. Imaging is not routine for children, since it frequently requires sedation. We present a pediatric LTH grading scale with substantial interrater reliability to facilitate standardization of endoscopy findings and promote outcomes-based research for OSA surgery in children.

Multidisciplinary care of children with repaired esophageal atresia and tracheoesophageal fistula.

OBJECTIVES: Children with congenital esophageal atresia with tracheoesophageal fistula (TEF) require complex medical and surgical care, but few guidelines exist to guide the long term care of this population. The purpose of this study is to describe the findings and initial management of a comprehensive aerodigestive team in order to understand the ongoing needs of children with repaired TEF. METHODS: A retrospective chart review was performed on children with TEF who were seen in the multidisciplinary Aerodigestive Clinic at Children's Hospital Colorado. Diagnostic studies were ordered based on physician discretion. RESULTS: Twenty-nine children with TEF were evaluated (mean age 3.8 years) between 2010 and 2014. All children had symptoms attributed to breathing, swallowing, and digestive difficulties. Less than half of the children had seen a pulmonary or gastrointestinal specialist in the past year. Tracheomalacia was diagnosed in all children who had a bronchoscopy (23/23), and the presence of dysphagia was correlated with severe tracheomalacia. 7/25 children who had a swallow study had aspiration. 7/25 children had a diagnosis of active reflux despite current management. Four patients were diagnosed with bronchiectasis as a result of the multidisciplinary evaluation. CONCLUSION: Although all children had persistent aerodigestive symptoms, over 50% had not been seen by an appropriate subspecialist in the year prior to the clinic visit. The multidisciplinary evaluation resulted in new diagnoses of bronchiectasis and active reflux, which can both lead to long-term morbidity and mortality. Children with TEF require evaluation by multiple subspecialists to manage not only current symptoms but also long term risks. Ongoing care should be guided by protocols based on known risks. Pediatr Pulmonol. 2016;51:576-581. © 2015 Wiley Periodicals, Inc.

Characteristics of children under 2 years of age undergoing tonsillectomy for upper airway obstruction.

INTRODUCTION: To study characteristics of children less than 2 years who underwent a tonsillectomy for sleep disordered breathing (SDB) or obstructive sleep apnea (OSA) to assess for factors associated with requesting a preoperative polysomnogram (PSG) and to identify predictors of upper airway obstruction in this group. MATERIALS AND METHODS: A retrospective chart review of children under 2 years who underwent a tonsillectomy over a 7-year period at a tertiary care pediatric hospital was undertaken. Patient demographics, characteristics and polysomnography results, when applicable, were collected. In order to determine if the gathered demographics of our cohort differed from the non-surgical population, we compared our data with available Colorado data for each variable. Children were stratified by OSA severity using their obstructive apnea-hypopnea index (OAHI). RESULTS: 197 (2.2%) of 9038 patients who underwent tonsillectomy for SDB or OSA were ≤ 24 months. The proportions of male, African-American, Hispanic, obese, underweight, premature, syndromic and daycare patients in our cohort were significantly different than in the general population. In a multivariate model, the odds of African-Americans having severe OSA were 12.5 times greater than the odds of Caucasians. The odds of patients with syndromes or craniofacial anomalies were 11 times greater (p < 0.0001), and the odds of patients in daycare were 2.2 times lower (p = 0.04) of undergoing a PSG before tonsillectomy. Weight did not influence polysomnogram requests. CONCLUSIONS: In children under 2 years, ethnicity seems to be a predictor of OSA severity. African-American, prematurity, daycare and Down syndrome patients were significantly more represented in our study population. PSG is more likely to be requested for syndromic children.