Acute respiratory failure due to pulmonary exacerbation in children with cystic fibrosis admitted in a pediatric intensive care unit: outcomes and factors associated with mortality

BACKGROUND

Children with advanced pulmonary disease due to cystic fibrosis (CF) are at risk of acute respiratory failure due to pulmonary exacerbations leading to their admission to pediatric intensive care units (PICU). The objectives of this study were to determine short and medium-term outcomes of children with CF admitted to PICU for acute respiratory failure due to pulmonary exacerbation and to identify prognosis factors.

METHODS

This retrospective monocentric study included patients less than 18 years old admitted to the PICU of a French university hospital between 2000 and 2020. Cox proportional hazard regression methods were used to determine prognosis factors of mortality or lung transplant.

RESULTS

Prior to PICU admission, the 29 patients included (median age 13.5 years) had a severe lung disease (median Forced Expiratory Volume in 1 s percentage predicted at 29%). Mortality rates were respectively 17%, 31%, 34%, 41% at discharge and at 3, 12 and 36 months post-discharge. Survival rates free of lung transplant were 34%, 32%, 24% and 17% respectively. Risk factors associated with mortality or lung transplant using the univariate analysis were female sex and higher pCO2 and chloride levels at PICU admission, and following pre admission characteristics: home respiratory and nutritional support, registration on lung transplant list and Stenotrophomonas Maltophilia bronchial colonization.

CONCLUSION

Children with CF admitted to PICU for acute respiratory failure secondary to pulmonary exacerbations are at high risk of death, both in the short and medium terms. Lung transplant is their main chance of survival and should be considered early.

Affinity fine-tuning anti-CAIX CAR-T cells mitigate on-target off-tumor side effects

One of the major hurdles that has hindered the success of chimeric antigen receptor (CAR) T cell therapies against solid tumors is on-target off-tumor (OTOT) toxicity due to sharing of the same epitopes on normal tissues. To elevate the safety profile of CAR-T cells, an affinity/avidity fine-tuned CAR was designed enabling CAR-T cell activation only in the presence of a highly expressed tumor associated antigen (TAA) but not when recognizing the same antigen at a physiological level on healthy cells. Using direct stochastic optical reconstruction microscopy (dSTORM) which provides single-molecule resolution, and flow cytometry, we identified high carbonic anhydrase IX (CAIX) density on clear cell renal cell carcinoma (ccRCC) patient samples and low-density expression on healthy bile duct tissues. A Tet-On doxycycline-inducible CAIX expressing cell line was established to mimic various CAIX densities, providing coverage from CAIX-high skrc-59 tumor cells to CAIX-low MMNK-1 cholangiocytes. Assessing the killing of CAR-T cells, we demonstrated that low-affinity/high-avidity fine-tuned G9 CAR-T has a wider therapeutic window compared to high-affinity/high-avidity G250 that was used in the first anti-CAIX CAR-T clinical trial but displayed serious OTOT effects. To assess the therapeutic effect of G9 on patient samples, we generated ccRCC patient derived organotypic tumor spheroid (PDOTS) ex vivo cultures and demonstrated that G9 CAR-T cells exhibited superior efficacy, migration and cytokine release in these miniature tumors. Moreover, in an RCC orthotopic mouse model, G9 CAR-T cells showed enhanced tumor control compared to G250. In summary, G9 has successfully mitigated OTOT side effects and in doing so has made CAIX a druggable immunotherapeutic target.

Neurologic Outcomes and Quality of Life in Children After Extracorporeal Membrane Oxygenation

RATIONALE

Use of life support with extracorporeal membrane oxygenation (ECMO) is associated with brain injury. However, the consequences of these injuries on subsequent neurologic development and health-related quality of life (HRQoL) are poorly described in children.

OBJECTIVES

The aim of this preliminary study was to describe short- and long-term neurologic outcomes in survivors of ECMO, as well as their HRQoL.

DESIGN

Retrospective identified cohort with contemporary evaluations.

SETTING

Necker Children's Hospital academic PICU.

PATIENTS

Forty survivors who underwent ECMO (October 2014 to January 2020) were included in follow-up assessments in May 2021.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

We first reviewed the outcomes of ECMO at the time of PICU discharge, which included a summary of neurology, radiology, and Pediatric Overall/Cerebral Performance Category (POPC/PCPC) scores. Then, in May 2021, we interviewed parents and patients to assess HRQoL (Pediatric Quality of Life Inventory [PedsQL]) and POPC/PCPC for children 3 years old or older, and Denver II test (DTII) for younger children. An evaluation of DTII in the youngest patients 1 year after ECMO decannulation was also added. Median age at ECMO was 1.4 years (interquartile range [IQR], 0.4-6 yr). Thirty-five children (88%) underwent a venoarterial ECMO. At PICU discharge, 15 of 40 patients (38%) had neurologic impairment. Assessment of HRQoL was carried out at median of 1.6 years (IQR, 0.7-3.3 yr) after PICU discharge. PedsQL scores were over 70 of 100 for all patients (healthy peers mean results: 80/100), and scores were like those published in patients suffering with chronic diseases. In May 2021, seven of 15 patients had a normal DTII, and 36 of 40 patients had a POPC/PCPC score less than or equal to 3.

CONCLUSIONS

None of our patients presented severe disability at long term, and HRQoL evaluation was reassuring. Considering the risk of neurologic impairment after ECMO support, a systematic follow-up of these high-risk survivor patients would be advisable.

Gasping in Dying Children: Health Care Professionals' Feelings and Knowledge

Purpose: To assess the feelings and knowledge of health care professionals (HCPs) about gasping in dying patients in neonatal intensive care units (NICUs) and pediatric intensive care units (PICUs). Methods: A 9-item questionnaire addressed to 488 HCPs (physicians, nurses, and nursing assistants) of 2 NICUs and 2 PICUs. Questions were about HCPs' feelings when confronted with gasping, their knowledge, and their opinions on what to tell family members. Results: Responses were obtained from 248 staff members. Of the respondents, 43% felt that gasping was painful to the patient and most felt that witnessing gasps was distressing for the parents, and 77% reported being distressed by witnessing gasps. Conclusions: Efforts are needed to educate HCPs about the physiology of gasping, to help them to cope with gasping, and to give better support to parents.

Visiting Policies and Parental Presence During PICU Admission: A Survey in French Units

OBJECTIVES

To describe the policies about parent visiting and involvement in care during admission to French PICUs.

DESIGN

A structured questionnaire was emailed to the chief of each of 35 French PICUs. Data about visiting policies, involvement in care, evolution of policies, and general characteristics were collected from April 2021 to May 2021. A descriptive analysis was conducted.

SETTING

Thirty-five PICUs in France.

PATIENTS

None.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Twenty-nine of 35 (83%) PICUs replied. Twenty-four-hour access for parents was reported for all PICUs responding. Other allowed visitors were grandparents (21/29, 72%) and siblings (19/29, 66%) with professional support. Simultaneous visits were restricted to two visitors in 83% (24/29) of PICUs. Family presence was always permitted during medical rounds for 20 of 29 (69%) PICUs. Most of the units rarely or never allowed parental presence during the most invasive procedures, such as central venous catheter placement (18/29, 62%) and intubation (22/29, 76%).

CONCLUSIONS

Unrestricted access to the PICU, for both parents, was available in all responding French units. There were, however, restrictions on the number of visitors and the presence of other family members at the bedside. Moreover, permission for parental presence during care procedures was heterogenous, and mainly restricted. National guidelines and educational programs are needed to support family wishes and promote acceptance by healthcare providers in French PICUs.

Abstract 886: Fine-tuned CAIX targeted CAR-T cells exhibit superior efficacy and mitigate on-target off-tumor side effects

Chimeric Antigen Receptor (CAR) T cell therapy is a new type of “living drug” that has proven to be a powerful immunotherapy for hematologic malignancies. To date, there are six CAR-T products approved by the FDA for hematologic malignancies, four targeting CD19, and two targeting B-cell maturation antigen (BCMA). However, this success has not yet been transferred to solid tumors. A major hurdle is the on-target off-tumor toxicities due to the shared expression of target antigen on normal tissues. Carbonic anhydrase IX (CAIX) is highly expressed in clear cell renal cell carcinoma (ccRCC); however, it is also expressed on bile duct at a lower physiological level leading to off-tumor toxicity of CAIX targeted therapies. The first anti-CAIX CAR-T studies, using the 1st generation G250 CAR-T cells plus IL-2 to treat patients with metastatic ccRCC, caused severe liver enzyme abnormalities in the treated patients after CAR-T cell infusions. To understand CAIX expression on tumor and normal tissues, we quantified CAIX expression on ccRCC patient samples and healthy bile duct tissues using direct stochastic optical reconstruction microscopy (dSTORM) which provides single-molecule resolution. Tet-On inducible CAIX expressing cell lines were established to mimic various CAIX densities on normal tissue and tumor samples. Using biolayer interferometry (BLI) and avidity analyzer, we identified a low-affinity, high-avidity anti-CAIX CAR G9. G9 CAR-T cells only kill CAIX high ccRCC tumor cells but not CAIX low normal cholangiocytes, and exhibited a CAIX density dependent response to Tet-On inducible CAIX expressing cell lines. Compared to high-affinity G250 CAR-T cells, G9 showed a better safety profile and a wider therapeutic window. G9 demonstrated a superior ex vivo efficacy on ccRCC patient derived organotypic tumor spheroids (PDOTS) 3D cultures which recapitulate ccRCC patient tumor microenvironment (TME), as well as low toxicity on cholangiocyte derived organotypic spheroids (CDOS). In summary, affinity/avidity fine-tuned CAIX targeted CAR-T cell therapy holds promise to achieve cures of ccRCC by efficaciously killing tumor cells and mitigating on-target off-tumor toxicity on normal tissues.

Citation Format: Yufei Wang, Alicia Buck, Gabriella Kastrunes, Rabia Abbas, Michael Lynch, Zhou Zhong, Song-My Hoang, Andras Miklosi, Kun Huang, Jae-Won Cho, Marion Grimaud, Cecile Razimbaud, Matthew Chang, Atef Fayed, Audrey Apollon, Nithyassree Murugan, Ze-Hua Li, Tran Thai, Luann Zerefa, Brandon Piel, Elena Ivanova, Amy Cameron, Quang-De Nguyen, Zhu Zhu, Kevin Wei, Yasmin Nabil Laimon, Aseman Bagheri Sheshdeh, Sabina Signoretti, David A. Braun, Catherine J. Wu, Toni K. Choueiri, Jon Wee, Cloud P. Paweletz, Martin Hemberg, Aedin C. Culhane, David A. Barbie, Gordon J. Freeman, Wayne A. Marasco. Fine-tuned CAIX targeted CAR-T cells exhibit superior efficacy and mitigate on-target off-tumor side effects [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 886.

Cerebral sinovenous thrombosis associated with head/neck infection in children: Clues for improved management

AIM

To compare paediatric patients with cerebral sinovenous thrombosis (CSVT) with and without head/neck infection to improve management of the condition.

METHOD

We conducted a bicentric retrospective study of consecutive children (neonates excluded) with radiologically confirmed CSVT, comparing children with a concurrent head/neck infection and children with other causes.

RESULTS

A total of 84 consecutive patients (46 males and 38 females) with a median age of 4 years 6 months (range 3 months-17 years 5 months) were included. Associated head/neck infection was identified in 65.4% of cases and represented the main identified CSVT aetiology. Children in the head/neck infection group displayed a milder clinical presentation and less extensive CSVT. Median time to complete recanalization was significantly shorter in this group (89 days [interquartile range 35-101] vs 112.5 days [interquartile range 83-177], p = 0.005). These findings were even more pronounced in the subgroup of patients with otogenic infection and no neurological sign.

INTERPRETATION

As CSVT in the setting of an otogenic infection and no neurological sign seems to represent a milder condition with a shorter course, these results suggest adapting current recommendations: consider earlier control imaging in paediatric otogenic CSVT, and shorter anticoagulant treatment if recanalization is obtained.

WHAT THIS PAPER ADDS

Children with cerebral sinovenous thrombosis related to head/neck infections have a milder clinical presentation. They also have a shorter recanalization time, especially if there is otogenic infection without neurological symptoms.

Abstract 2814: Anti-CAIX Immune Restoring (IR) CAR-T cells display superior antitumor activity and reverse immunosuppressive TME in a humanized ccRCC orthotopic mouse model

Chimeric Antigen Receptor (CAR) T cell therapy is a new type of “living drug” that has proven to be a powerful, clinically translatable immunotherapy for hematologic malignancies. To date, there are five CAR-T products approved by FDA, four CD19 targeted CAR-T cells, and one targeting B-cell maturation antigen (BCMA). However, this success has not yet been transferred to solid tumors. A major challenge is the immunosuppressive tumor microenvironment (TME). Development of immunotherapies has traditionally been hampered by discrepancies observed between in vitro and in vivo studies and actual clinical trial outcomes. The lack of clinically relevant mouse models for human immunotherapy testing is often seen as the primary cause. Existing clear cell renal cell carcinoma (ccRCC) in vivo models poorly recapitulate the tumor microenvironment (TME). Here we report a ccRCC orthotopic humanized NSG-SGM3 mouse model (ccRCC-hNSG-SGM3) with reconstituted human lymphocytes and bearing human ccRCC skrc-59 cells under the kidney capsule. Human leukocyte antigen (HLA) matched CD34+ human stem cells were used for the humanization to reduce T cell alloreactivity against skrc-59 human ccRCC cells. Tumors were harvested, sorted for CD45+ tumor infiltrating leukocytes (TILs) and single cell RNA sequencing (scRNAseq) was performed to profile the TME in ccRCC-hNSG-SGM3. By comparing to patient data from prospective clinical trials of the anti-PD-1 monoclonal antibody (mAb) nivolumab in advanced ccRCC, the results demonstrated that CD45+ TILs from ccRCC-hNSG-SGM3 reconstitute most CD45+ cell types, including dendritic cells, exhausted CD8 T cells, and regulatory T cells (Tregs), that are observed in advanced ccRCC patient TME. Furthermore, we generated HLA matched Immune Restoring (IR) CAR-T cells which can secrete anti-PD-L1 monoclonal antibody (mAb) locally to restore active antitumor immunity, and we assessed the efficacy and safety of IR CAR-T cells in this model. Anti-CAIX CAR-T cells armored with anti-PD-L1 mAb showed superior efficacy in tumor regression and significantly decreased TIL exhaustion compared to irrelevant CAR or irrelevant payload in this model. In addition, in situ hybridization (ISH) results showed CAR-T cells infiltration in tumor but no CAR-T cells were observed in normal tissues. In summary, the ccRCC-hNSG-SGM3 system is able to model the advanced ccRCC TME and provides a powerful tool for ccRCC TME study and immunotherapy assessment. IR CAR-T cells exhibited superior tumor regression and reversed immunosuppressive TME in humanized mice.

Citation Format: Yufei Wang, Alicia Buck, Marion Grimaud, Aedin Culhane, David Braun, Sreekumar Kodangattil, Cecile Razimbaud, Matthew Chang, Atef Fayed, Audrey Apollon, Gabriella Kastrunes, Luann Zerefa, Brandon Piel, Elena Ivanova, Dennis Bonal, Kristen Jones, Quang-De Nguyen, Zhu Zhu, Kevin Wei, Nicholas Hayden, Madison O'Donnell, Ying Huang, Rebecca Jenning, Miriam Ficial, Maura Aliezah Sticco-Ivins, Sabina Signoretti, Catherine Wu, Toni Choueiri, Jon Wee, Cloud Paweletz, David A. Barbie, Gordon Freeman, Wayne A. Marasco. Anti-CAIX Immune Restoring (IR) CAR-T cells display superior antitumor activity and reverse immunosuppressive TME in a humanized ccRCC orthotopic mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2814.

Anti-CAIX BBζ CAR4/8 T cells exhibit superior efficacy in a ccRCC mouse model

Improving CAR-T cell therapy for solid tumors requires a better understanding of CAR design and cellular composition. Here, we compared second-generation (BBζ and 28ζ) with third-generation (28BBζ) carbonic anhydrase IX (CAIX)-targeted CAR constructs and investigated the antitumor effect of CAR-T cells with different CD4/CD8 proportions in vitro and in vivo. The results demonstrated that BBζ exhibited superior efficacy compared with 28ζ and 28BBζ CAR-T cells in a clear-cell renal cell carcinoma (ccRCC) skrc-59 cell bearing NSG-SGM3 mouse model. The mice treated with a single dose of BBζ CD4/CD8 mixture (CAR4/8) showed complete tumor remission and remained tumor-free 72 days after CAR-T cells infusion. In the other CAR-T and control groups, tumor-infiltrating T cells were recovered and profiled. We found that BBζ CAR8 cells upregulated expression of major histocompatibility complex (MHC) class II and cytotoxicity-associated genes, while downregulating inhibitory immune checkpoint receptor genes and diminishing differentiation of regulatory T cells (Treg cells), leading to excellent therapeutic efficacy in vivo. Increased memory phenotype, elevated tumor infiltration, and decreased exhaustion genes were observed in the CD4/8 untransduced T (UNT) cells compared with CD8 alone, indicating that CD4/8 would be the favored cellular composition for CAR-T cell therapy with long-term persistence. In summary, these findings support that BBζ CAR4/8 cells are a highly potent, clinically translatable cell therapy for ccRCC.

Therapeutic approach to pediatric patients with acute chest syndrome: national multicenter survey of non invasive ventilation (NIV) and transfusion

BACKGROUND

Intensive care units (ICUs) have seen a spike in the use of noninvasive ventilation (NIV) for many medical conditions. We sought to investigate the attitudes and clinical practice regarding the management of acute chest syndrome (ACS) with a focus on NIV in pediatric ICUs.

METHOD

Members of the French Group for Pediatric Intensive Care Emergencies (GFRUP) were asked to complete an online survey on physicians' attitudes toward children with ACS admitted to the PICU during 2015.

RESULTS

The survey was answered by teams from 17 PICUs (240 beds). In total, 15 centers (88%) had a local transfusion unit and 14 (82%) worked in connection with a sickle cell disease (SCD) reference center. During 2015, 360 patients with SCD were managed (median: 7 per center; 21) of whom 137 (38%) for an ACS (median: 4 ACS per center; 8). The median length of PICU stay for ACS was 5 days (3.1). Among the 137 patients who presented with ACS, 73 (53%) received simple blood transfusion and 16 (12%) received exchange transfusion. For patients who required noninvasive ventilatory support, NIV with bilevel pressure (BiPAP) was the most frequent method (n = 68, 50%), followed by continuous positive airway pressure (CPAP) (n = 23, 17%) and high-flow oxygen (n = 21, 15%). The proportion of patients on BiPAP was up to 71% in the centers most frequently managing ACS patients.

CONCLUSION

BiPAP is commonly used in PICUs for SCD patients with ACS, especially in trained centers. Future physiological studies and randomized controlled trials might help to choose the best ventilatory support for ACS.

Abstract 62: Development of dual-targeted fine-tuned immune restoring (DFIR) CAR T cell therapy for clear cell renal cell carcinoma (ccRCC)

Clear cell renal cell carcinoma (ccRCC) is the major type of RCC and is among the 10 most common cancers in both men and women. Treatment of RCC has improved dramatically over the last decade, however, a curative treatment for advanced RCC remains rare. Chimeric Antigen Receptor (CAR) T cell therapy is a new type of “living drug”. The FDA approval of CAR-T cell therapies have ushered this new type of cellular immunotherapy into mainstream cancer therapy for hematologic malignancies. To date, these results have not been translatable to solid tumors due to inefficient homing of CAR-T cells, the immunosuppressive tumor microenvironment (TME), and on-target off-tumor toxicities due to shared antigens on normal tissues. Carbonic anhydrase IX (CAIX) is a therapeutic target against ccRCC that is under the control of HIF1α and becomes overexpressed on the surface of ccRCC cells because of VHL inactivation. The first anti-CAIX CAR-T study using the 1st generation G250-CD3 CAR-T cells plus IL-2 to treat patients with metastatic ccRCC was terminated due to hepatitis that developed after CAR-T cell infusions. The on-target off-tumor side effects were attributed to low expression of CAIX on healthy bile duct cells. To translate CAR-T cell therapy to ccRCC, we designed dual-targeted fine-tuned immune restoring (DFIR) CAR-T cells. The DFIR-CAR T cells secreted immune checkpoint inhibitor (ICI) monoclonal antibodies at the tumor site and exhibited superior efficacy and safety profiling. Increased efficacy is achieved through anti-CD70/CAIX dual-targeting CAR which allows the CAR-T cell activation in response to either antigen to mitigate solid tumor heterogeneity. Elevated safety is addressed through fine-tuned CARs which have the affinities of the scFv targeting moieties tailored so that they are activated only by high density tumor associated antigens (TAAs) but not the same antigens expressed at physiologic levels on normal tissues. The ICI payloads act globally on the TME, not only to prevent CAR-T cell exhaustion but also to restore anti-tumor activity of the educated tumor infiltrated lymphocytes (TILs) that have accumulated in the TME. In summary, our DFIR CAR-T cell therapy holds the promise to achieve cures of ccRCC by killing heterogenous ccRCC cells, mitigating against on-target off-tumor toxicity, reversing TME immunosuppression and restoring host anti-tumor immunity. We believe that DFIR-CAR T cells are ready to be translated to the clinic upon completion of pre-IND studies.

Citation Format: Yufei Wang, Alicia Buck, Marion Grimaud, Sreekumar Kodangattil, Cecile Razimbaud, Atef Fayed, Matthew Chang, Aedin Culhane, David A. Braun, Toni K. Choueiri, Catherine J. Wu, Kevin S. Wei, Leo L. Chan, Brandon P. Piel, Elena V. Ivanova, Cloud P. Paweletz, David A. Barbie, Rebecca Jennings, Miriam Ficial, Maura Aliezah Sticco-Ivins, Sabina Signoretti, Gordon J. Freeman, Quan K. Zhu, Wayne A. Marasco. Development of dual-targeted fine-tuned immune restoring (DFIR) CAR T cell therapy for clear cell renal cell carcinoma (ccRCC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 62.

Association of Intravenous Immunoglobulins Plus Methylprednisolone vs Immunoglobulins Alone With Course of Fever in Multisystem Inflammatory Syndrome in Children

IMPORTANCE

Multisystem inflammatory syndrome in children (MIS-C) is the most severe pediatric disease associated with severe acute respiratory syndrome coronavirus 2 infection, potentially life-threatening, but the optimal therapeutic strategy remains unknown.

OBJECTIVE

To compare intravenous immunoglobulins (IVIG) plus methylprednisolone vs IVIG alone as initial therapy in MIS-C.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study drawn from a national surveillance system with propensity score-matched analysis. All cases with suspected MIS-C were reported to the French National Public Health Agency. Confirmed MIS-C cases fulfilling the World Health Organization definition were included. The study started on April 1, 2020, and follow-up ended on January 6, 2021.

EXPOSURES

IVIG and methylprednisolone vs IVIG alone.

MAIN OUTCOMES AND MEASURES

The primary outcome was persistence of fever 2 days after the introduction of initial therapy or recrudescence of fever within 7 days, which defined treatment failure. Secondary outcomes included a second-line therapy, hemodynamic support, acute left ventricular dysfunction after first-line therapy, and length of stay in the pediatric intensive care unit. The primary analysis involved propensity score matching with a minimum caliper of 0.1.

RESULTS

Among 181 children with suspected MIS-C, 111 fulfilled the World Health Organization definition (58 females [52%]; median age, 8.6 years [interquartile range, 4.7 to 12.1]). Five children did not receive either treatment. Overall, 3 of 34 children (9%) in the IVIG and methylprednisolone group and 37 of 72 (51%) in the IVIG alone group did not respond to treatment. Treatment with IVIG and methylprednisolone vs IVIG alone was associated with lower risk of treatment failure (absolute risk difference, -0.28 [95% CI, -0.48 to -0.08]; odds ratio [OR], 0.25 [95% CI, 0.09 to 0.70]; P = .008). IVIG and methylprednisolone therapy vs IVIG alone was also significantly associated with lower risk of use of second-line therapy (absolute risk difference, -0.22 [95% CI, -0.40 to -0.04]; OR, 0.19 [95% CI, 0.06 to 0.61]; P = .004), hemodynamic support (absolute risk difference, -0.17 [95% CI, -0.34 to -0.004]; OR, 0.21 [95% CI, 0.06 to 0.76]), acute left ventricular dysfunction occurring after initial therapy (absolute risk difference, -0.18 [95% CI, -0.35 to -0.01]; OR, 0.20 [95% CI, 0.06 to 0.66]), and duration of stay in the pediatric intensive care unit (median, 4 vs 6 days; difference in days, -2.4 [95% CI, -4.0 to -0.7]).

CONCLUSIONS AND RELEVANCE

Among children with MIS-C, treatment with IVIG and methylprednisolone vs IVIG alone was associated with a more favorable fever course. Study interpretation is limited by the observational design.

Association of Cerebral Oxymetry with Short-Term Outcome in Critically ill Children Undergoing Extracorporeal Membrane Oxygenation

BACKGROUND

Acute brain injury (ABI) is a frequent complication of pediatric extracorporeal membrane oxygenation (ECMO) that could be detected by continuous neuromonitoring. Cerebral near-infrared spectroscopy (NIRS) allows monitoring of cerebral oxygenation.

OBJECTIVE

To assess whether an impaired cerebral oxygenation was associated with short-term outcome during pediatric ECMO.

METHODS

We conducted a single-center retrospective study in a pediatric intensive care unit. Children under 18 years old were included if receiving veno-venous or veno-arterial ECMO with concurrent NIRS monitoring. Cerebral saturation impairment was defined as rScO2 under 50% or 20% from the baseline for desaturation, and above 80%. Cerebral imaging (magnetic resonance imaging or CT scan) was performed in case of neurological concern. A radiologist blinded for patient history identified ABI as any hemorragic or ischemic lesion, then classified as major or minor. Primary endpoint was the outcome at hospital discharge. Poor outcome was defined as death or survival with a pediatric cerebral performance category scale (PCPC) score ≥ 3 and/or a major ABI. Good outcome was defined as survival with a PCPC score ≤ 2 and/or a minor or no ABI. Secondary endpoint was mortality before PICU discharge.

RESULTS

Sixty-three patients met inclusion criteria; 48 (76%) had veno-arterial ECMO. Mortality rate was 51%. Forty-eight of sixty-three patients (76%) evolved with a poor outcome, including 20 major ABI. Mean rScO2 in the right/left hemisphere was 73 ± 9%/75 ± 9%. Cerebral desaturation and decline of rScO₂ below 20% from the baseline, regardless of side, were each associated with poor outcome (multivariable-adjusted odds ratio (OR), 4 [95%CI 1.2; 15.1], p = 0.03, and 3.9 [95%CI 1.1; 14.9], p = 0.04, respectively), as well as a mean right rScO₂ < 70% during the ECMO course (adjusted OR, 5.6 [95%CI 1.3; 34], p = 0.04). Left rSCO₂ ≥ 80% was inversely correlated with hospital mortality (adjusted OR of 0.14 [95%CI 0.02; 0.8], p = 0.04).

CONCLUSIONS

Cerebral desaturation attested by NIRS was associated with a poor short-term outcome in children of all ages undergoing ECMO, and rScO2 > 80% seemed to be protective. NIRS monitoring might be included within multimodal neuromonitoring to assess the risk of the brain injury related to pediatric ECMO.

Simple actions to support breastfeeding can avoid unwanted weaning in infants younger than 6 months hospitalized for bronchiolitis: A before/after study (Bronchilact II)

BACKGROUND

Admission to hospital with bronchiolitis may adversely affect breastfeeding. Correct advice and support have been pointed out as a determining factor.

OBJECTIVES

We conducted a telephone survey to evaluate a set of actions to promote breastfeeding during hospitalization for acute bronchiolitis.

METHODS

Population: All patients 6 months of age or younger hospitalized with acute bronchiolitis and receiving at least partial breastfeeding were eligible for the study. Patients discharged home whose parents accepted to be contacted by phone were also included.

INTERVENTION

We established a set of actions to promote breastfeeding (posters, flyers, staff training, and equipment) in all pediatric wards attending to these patients.

COMPARISON

This was a cross-sectional study conducted during two epidemic seasons of bronchiolitis in a tertiary care hospital. Data on continued breastfeeding at 3 months (0.5-6; median, range) postdischarge were collected by telephone and compared with the same set of data collected from patients with bronchiolitis in the same setting the year before the intervention.

OUTCOME

We conducted a telephone survey to evaluate whether some actions regarding breastfeeding might diminish the risk of unwanted weaning during hospitalization for bronchiolitis. The primary outcome was the proportion of stopped or reduced breastfeeding at discharge. Secondary objectives were to evaluate whether there were factors associated with breastfeeding modification.

RESULTS

The results of the evaluation before intervention (phase 1) are published by Heilbronner et al. In Phase 1 of our study, 84 patients were included and 43 mothers (51%) reported that breastfeeding was modified by hospitalization of their child: 20.4% stopped, 14% switched to partial breastfeeding, and 16.6% reduced breastfeeding. These mothers stated that causes of breastfeeding disturbances were lack of support and advice (63%), followed by severity of the child's respiratory disease (32%), logistical hospital difficulties (30%), and personal organizational issues (9.3%). The intervention took place in September. After the intervention, 50 patients could be included in the study between October 1and December 31, 2016. Among them, 40 (80%) mothers kept breastfeeding as before, four (8%) stopped, four (8%) switched to partial breastfeeding, and two (4%) reduced breastfeeding without stopping. Bronchiolitis was more severe among patients with altered breastfeeding in terms of ventilatory support.

CONCLUSION

Bronchiolitis is a high-risk event for breastfeeding disruption but interventions to promote breastfeeding might help to prevent the risk of unwanted weaning. More severe bronchiolitis probably poses the highest risk of weaning and the need for supplementary nutrition.

High-Throughput Image Cytometry Detection Method for CAR-T Transduction, Cell Proliferation, and Cytotoxicity Assays

Chimeric antigen receptor (CAR)-T cell therapy has drawn much attention due to its recent clinical success in B-cell malignancies. In general, the CAR-T cell discovery process consists of CAR identification, T-cell activation, transduction, and expansion, as well as assessment of CAR-T cytotoxicity. The current evaluation methods for the CAR-T discovery process can be time-consuming, low-throughput and requires the preparation of multiple sacrificial samples in order to produce kinetic data. In this study, we employed the use of a plate-based image cytometer to monitor anti-CAIX (carbonic anhydrase IX) G36 CAR-T generation and assess its cytotoxic potency of direct and selective killing against CAIX⁺ SKRC-59 human renal cell carcinoma cells. The transduction efficiency and cytotoxicity results were analyzed using image cytometry and compared directly to flow cytometry and Chromium 51 (⁵¹ Cr) release assays, showing that image cytometry was comparable against these conventional methods. Image cytometry method streamlines the assays required during the CAR-T cell discovery process by analyzing a plate of T cells from CAR-T generation to in vitro functional assays with minimum disruption. The proposed method can reduce assay time and uses less cell samples by imaging and analyze the same plate over time without the need to sacrifice any cells. The ability to monitor kinetic data can allow additional insights into the behavior and interaction between CAR-T and target tumor cells. © 2020 International Society for Advancement of Cytometry.

Severe and fatal forms of COVID-19 in children

Objectives

The aim of this study was to describe severe forms of novel coronavirus disease 2019 in children, including patient characteristics, clinical, laboratory, and imaging findings, as well as the disease management and outcomes.

Methods

This was a retrospective, single-center, observational study conducted in a pediatric intensive and high-dependency care unit (PICU, HDU) in an urban hospital in Paris. All patients, aged from 1 month to 18 years, admitted for confirmed or highly suspected SARS-CoV-2 were included.

Results

We analyzed the data of 27 children. Comorbidities (n = 19, 70%) were mainly neurological (n = 7), respiratory, (n = 4), or sickle cell disease (n = 4). SARS-CoV-2 PCR results were positive in 24 children (nasopharyngeal swabs). The three remaining children had a chest CT scan consistent with COVID-19. Respiratory involvement was observed in 24 patients (89%). Supportive treatments were invasive mechanical ventilation (n = 9), catecholamine (n = 4), erythropheresis (n = 4), renal replacement therapy (n = 1), and extracorporeal membrane oxygenation (n = 1). Five children died, of whom three were without past medical history.

Conclusion

This study highlighted the large spectrum of clinical presentation and time course of disease progression as well as the non-negligible occurrence of pediatric life-threatening and fatal cases of COVID-19 mostly in patients with comorbidities. Additional laboratory investigations are needed to further analyze the mechanism underlying the variability of SARS-Cov-2 pathogenicity in children.

Acute myocarditis and multisystem inflammatory emerging disease following SARS-CoV-2 infection in critically ill children

BACKGROUND

A recent increase in children admitted with hypotensive shock and fever in the context of the COVID-19 outbreak requires an urgent characterization and assessment of the involvement of SARS-CoV-2 infection. This is a case series performed at 4 academic tertiary care centers in Paris of all the children admitted to the pediatric intensive care unit (PICU) with shock, fever and suspected SARS-CoV-2 infection between April 15th and April 27th, 2020.

RESULTS

20 critically ill children admitted for shock had an acute myocarditis (left ventricular ejection fraction, 35% (25-55); troponin, 269 ng/mL (31-4607)), and arterial hypotension with mainly vasoplegic clinical presentation. The first symptoms before PICU admission were intense abdominal pain and fever for 6 days (1-10). All children had highly elevated C-reactive protein (> 94 mg/L) and procalcitonin (> 1.6 ng/mL) without microbial cause. At least one feature of Kawasaki disease was found in all children (fever, n = 20, skin rash, n = 10; conjunctivitis, n = 6; cheilitis, n = 5; adenitis, n = 2), but none had the typical form. SARS-CoV-2 PCR and serology were positive for 10 and 15 children, respectively. One child had both negative SARS-CoV-2 PCR and serology, but had a typical SARS-CoV-2 chest tomography scan. All children but one needed an inotropic/vasoactive drug support (epinephrine, n = 12; milrinone, n = 10; dobutamine, n = 6, norepinephrine, n = 4) and 8 were intubated. All children received intravenous immunoglobulin (2 g per kilogram) with adjuvant corticosteroids (n = 2), IL 1 receptor antagonist (n = 1) or a monoclonal antibody against IL-6 receptor (n = 1). All children survived and were afebrile with a full left ventricular function recovery at PICU discharge.

CONCLUSIONS

Acute myocarditis with intense systemic inflammation and atypical Kawasaki disease is an emerging severe pediatric disease following SARS-CoV-2 infection. Early recognition of this disease is needed and referral to an expert center is recommended. A delayed and inappropriate host immunological response is suspected. While underlying mechanisms remain unclear, further investigations are required to target an optimal treatment.

Acute Heart Failure in Multisystem Inflammatory Syndrome in Children in the Context of Global SARS-CoV-2 Pandemic

BACKGROUND

Cardiac injury and myocarditis have been described in adults with coronavirus disease 2019 (COVID-19). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children is typically minimally symptomatic. We report a series of febrile pediatric patients with acute heart failure potentially associated with SARS-CoV-2 infection and the multisystem inflammatory syndrome in children as defined by the US Centers for Disease Control and Prevention.

METHODS

Over a 2-month period, contemporary with the SARS-CoV-2 pandemic in France and Switzerland, we retrospectively collected clinical, biological, therapeutic, and early outcomes data in children who were admitted to pediatric intensive care units in 14 centers for cardiogenic shock, left ventricular dysfunction, and severe inflammatory state.

RESULTS

Thirty-five children were identified and included in the study. Median age at admission was 10 years (range, 2-16 years). Comorbidities were present in 28%, including asthma and overweight. Gastrointestinal symptoms were prominent. Left ventricular ejection fraction was <30% in one-third; 80% required inotropic support with 28% treated with extracorporeal membrane oxygenation. Inflammation markers were suggestive of cytokine storm (interleukin-6 median, 135 pg/mL) and macrophage activation (D-dimer median, 5284 ng/mL). Mean BNP (B-type natriuretic peptide) was elevated (5743 pg/mL). Thirty-one of 35 patients (88%) tested positive for SARS-CoV-2 infection by polymerase chain reaction of nasopharyngeal swab or serology. All patients received intravenous immunoglobulin, with adjunctive steroid therapy used in one-third. Left ventricular function was restored in the 25 of 35 of those discharged from the intensive care unit. No patient died, and all patients treated with extracorporeal membrane oxygenation were successfully weaned.

CONCLUSIONS

Children may experience an acute cardiac decompensation caused by severe inflammatory state after SARS-CoV-2 infection (multisystem inflammatory syndrome in children). Treatment with immunoglobulin appears to be associated with recovery of left ventricular systolic function.

High glucose intake and glycaemic level in critically ill neonates with inherited metabolic disorders of intoxication

To investigate glycaemic levels in critically ill neonates with inherited metabolic disorders of intoxication. Thirty-nine neonates with a median age of 7 days (0-24) were retrospectively included (urea cycle disorders (n = 18), maple syrup disease (n = 13), organic acidemias (n = 8)). Twenty-seven neonates were intubated, 21 were haemodialysed and 6 died. During the first 3 days, median total and peak blood glucose (BG) levels were 7.1 mmol/L (0.9-50) and 10 mmol/L (5.1-50), respectively. The median glucose intake rate was 11 mg/kg/min (2.7-15.9). Fifteen and 23 neonates exhibited severe hyperglycaemia (≥2 BG levels >12 mmol/L) and mild hyperglycaemia (≥2 BG levels >7 and ≤12 mmol/L), respectively. Glycaemic levels and number of hyperglycaemic neonates decreased over the first 3 days (p < 0.001) while total glucose intake rate was stable (p = 0.11). Enteral route of glucose intake was associated with a lower number of hyperglycaemic neonates (p = 0.04) and glycaemic level (p = 0.02).

CONCLUSION

Hyperglycaemia is common in critically ill neonates receiving high glucose intake with inherited metabolic disorders of intoxication. Physicians should decrease the rate of total glucose intake and begin enteral feeding as quickly as possible in cases of persistent hyperglycaemia.

WHAT IS KNOWN

• The risk of hyperglycaemia in the acute phase of critical illness is high. What is New: • Hyperglycaemia is common in the initial management of critically ill neonates with inherited metabolic disorders of intoxication receiving high glucose intake.

[Fanconi anemia in 2012: diagnosis, pediatric follow-up and treatment]

Fanconi anemia (FA) is a rare genetic disease, transmitted in an autosomal recessive mode. The clinical phenotype is very broad and heterogeneous, related to the wide range of genes involved in this pathology. The classical triad of short height, physical abnormalities, and bone marrow failure is suggestive. The main physical abnormalities found involve the limbs, spinal column, skin, kidneys and urinary tract, and the ORL zone. Recent progress in molecular biology has identified 15 genes whose mutation causes FA chromosomal instability. FA is diagnosed by cytogenetic examination, then specified by molecular analysis. As FA patients may present multiorgan abnormalities and a high risk for neoplasia development, their medical follow-up has to be multidisciplinary and prolonged throughout life. The main challenges of the follow-up are patient information and education. Bone marrow failure, appearing during the first decade, requires close hematological monitoring and for severe cases requires hematopoietic stem cell transplantation, major and specific care with frequent serious complications and high mortality, but this is the only curative treatment in FA. Extrahematological care consists in screening for organ abnormalities and defects as well as monitoring precancerous lesions and tumors.

Germinal center analysis with the tools of mathematical morphology on graphs

Only few studies devoted to quantitative analysis of tissue architecture have been performed. The analysis of neighborhood relationships between cells, using graphs and mathematical morphology (MM), constitutes one approach. We propose to analyse quantitatively the architecture of a tissue with the tools of MM on graphs. The use of graphs seems best suited to take into account the neighborhood relationships between cells, independently from their mutual distances: two cells are considered as neighbors if no interfering cell is placed in a given sense between them. Such neighboring cells are linked by an arc in a graph. On such a graph, all tools of MM may be applied. We investigate two of them in the present work: (1) the distance transforms permits to analyse the repartition of a cellular population A relative to population B, (2) the size distribution permits to analyse the tendancy of a cell population to form clusters. We have applied this method using Gabriel's graph, derived from the Voronoï diagram, to determine the "zone of influence" of a cell. We have analysed the neighborhood relationships between cells in germinal centers (GC) from lymph nodes. Twelve hyperplastic GCs from follicular hyperplasia (FH) and 5 neoplastic GCs from small cleaved cell follicular lymphoma (++SCCFL) have been studied; 2 microns hematoxylin-eosin plastic embedded sections have been analysed. Cell nuclei have been identified manually by the observer by giving a numerical and image color code. Gabriel's graphs have been constructed with all centrofollicular cells. Subgraphs with only lymphoid cells, large cells or small cleaved cells have also been studied. The application of MM transformations on the graphs using software package Morphograph has allowed a quantitative description of cell distribution in the tissue. The distances of centrofollicular lymphoid cells from the periphery of the GCs (mantle zone), from nonlymphoid cells as macrophages located within the GCs and between large lymphoid cells and small lymphoid cells have been determined in FH and SCCFL. Using iterative closings and openings, we have detected aggregates of small and large cells and characterized their size and distribution in the GCs. The application of this method on lymph node biopsy has allowed a quantitative description and comparison of GCs in different pathological conditions.

Étude de la flash thermolyse du méthyl-5 azido-2 thiadiazole-1,3,4 par spectroscopie photoélectronique (HeI) et calculs quantiques

The flash thermolysis of 5-methyl 2-azido 1,3,4-thiadiazole (vapour phase: 10−2 mbar) was studied by ultraviolet photoelectron spectroscopy (HeI). The products detected (H2C=C=S, HCN, and N2) suggest that the unstable thiadiazole-nitrene undergoes a ring opening to form a linear thione 4, which generates the thiocetene H2C=C=S. This step was theoretically analysed by the MNDO method.

Gas phase flash pyrolysis of 3-azido-1,2,4-triazole: generation and ultraviolet photoelectron spectrum of N-cyanomethanimine

A dimer of HCN, N-cyanomethanimine 6, was prepared by flash pyrolysis (gas phase, 10−2 mbar) from 3-azido-1,2,4-triazole 1a and detected by ultraviolet photoelectron spectroscopy (HeI). Its ionization potentials were measured and the ionic states sequence proposed, with the aid of ab initio – CI (configuration interaction) calculations. The study of the MNDO potential hypersurface enabled us to propose a mechanism of the thermal reorganization of the precursor 1a. It is shown that the reaction path passes through the formation of the protomer 1b before thermal decomposition and the generation of the nitrene 2b.