Pre-existing Immunocompromising Conditions and Outcomes of Acute COVID-19 Patients Admitted for Pediatric Intensive Care.

BACKGROUND: We aimed to determine if pre-existing immunocompromising conditions (ICCs) were associated with the presentation or outcome of patients with acute coronavirus disease 2019 (COVID-19) admitted for pediatric intensive care. METHODS: 55 hospitals in 30 U.S. states reported cases through the Overcoming COVID-19 public health surveillance registry. Patients <21 years admitted March 12, 2020-December 30, 2021 to the pediatric intensive care unit (PICU) or high acuity unit for acute COVID-19 were included. RESULTS: Of 1,274 patients, 105 (8.2%) had an ICC including 33 (31.4%) hematologic malignancies, 24 (22.9%) primary immunodeficiencies and disorders of hematopoietic cells, 19 (18.1%) nonmalignant organ failure with solid organ transplantation, 16 (15.2%) solid tumors and 13 (12.4%) autoimmune disorders. Patients with ICCs were older, had more underlying renal conditions, and had lower white blood cell and platelet counts than those without ICCs, but had similar clinical disease severity upon admission. In-hospital mortality from COVID-19 was higher (11.4% vs. 4.6%, p = 0.005) and hospitalization was longer (p = 0.01) in patients with ICCs. New major morbidities upon discharge were not different between those with and without ICC (10.5% vs 13.9%, p = 0.40). In patients with ICC, bacterial co-infection was more common in those with life-threatening COVID-19. CONCLUSIONS: In this national case series of patients <21 years of age with acute COVID-19 admitted for intensive care, existence of a prior ICCs were associated with worse clinical outcomes. Reassuringly, most patients with ICCs hospitalized in the PICU for severe acute COVID-19 survived and were discharged home without new severe morbidities.

Extracorporeal Membrane Oxygenation Characteristics and Outcomes in Children and Adolescents With COVID-19 or Multisystem Inflammatory Syndrome Admitted to U.S. ICUs.

OBJECTIVES: Extracorporeal membrane oxygenation (ECMO) has been used successfully to support adults with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related cardiac or respiratory failure refractory to conventional therapies. Comprehensive reports of children and adolescents with SARS-CoV-2-related ECMO support for conditions, including multisystem inflammatory syndrome in children (MIS-C) and acute COVID-19, are needed. DESIGN: Case series of patients from the Overcoming COVID-19 public health surveillance registry. SETTING: Sixty-three hospitals in 32 U.S. states reporting to the registry between March 15, 2020, and December 31, 2021. PATIENTS: Patients less than 21 years admitted to the ICU meeting Centers for Disease Control criteria for MIS-C or acute COVID-19. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The final cohort included 2,733 patients with MIS-C ( n = 1,530; 37 [2.4%] requiring ECMO) or acute COVID-19 ( n = 1,203; 71 [5.9%] requiring ECMO). ECMO patients in both groups were older than those without ECMO support (MIS-C median 15.4 vs 9.9 yr; acute COVID-19 median 15.3 vs 13.6 yr). The body mass index percentile was similar in the MIS-C ECMO versus no ECMO groups (89.9 vs 85.8; p = 0.22) but higher in the COVID-19 ECMO versus no ECMO groups (98.3 vs 96.5; p = 0.03). Patients on ECMO with MIS-C versus COVID-19 were supported more often with venoarterial ECMO (92% vs 41%) for primary cardiac indications (87% vs 23%), had ECMO initiated earlier (median 1 vs 5 d from hospitalization), shorter ECMO courses (median 3.9 vs 14 d), shorter hospital length of stay (median 20 vs 52 d), lower in-hospital mortality (27% vs 37%), and less major morbidity at discharge in survivors (new tracheostomy, oxygen or mechanical ventilation need or neurologic deficit; 0% vs 11%, 0% vs 20%, and 8% vs 15%, respectively). Most patients with MIS-C requiring ECMO support (87%) were admitted during the pre-Delta (variant B.1.617.2) period, while most patients with acute COVID-19 requiring ECMO support (70%) were admitted during the Delta variant period. CONCLUSIONS: ECMO support for SARS-CoV-2-related critical illness was uncommon, but type, initiation, and duration of ECMO use in MIS-C and acute COVID-19 were markedly different. Like pre-pandemic pediatric ECMO cohorts, most patients survived to hospital discharge.

Community-Onset Bacterial Coinfection in Children Critically Ill With Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

Background: Community-onset bacterial coinfection in adults hospitalized with coronavirus disease 2019 (COVID-19) is reportedly uncommon, though empiric antibiotic use has been high. However, data regarding empiric antibiotic use and bacterial coinfection in children with critical illness from COVID-19 are scarce. Methods: We evaluated children and adolescents aged <19 years admitted to a pediatric intensive care or high-acuity unit for COVID-19 between March and December 2020. Based on qualifying microbiology results from the first 3 days of admission, we adjudicated whether patients had community-onset bacterial coinfection. We compared demographic and clinical characteristics of those who did and did not (1) receive antibiotics and (2) have bacterial coinfection early in admission. Using Poisson regression models, we assessed factors associated with these outcomes. Results: Of the 532 patients, 63.3% received empiric antibiotics, but only 7.1% had bacterial coinfection, and only 3.0% had respiratory bacterial coinfection. In multivariable analyses, empiric antibiotics were more likely to be prescribed for immunocompromised patients (adjusted relative risk [aRR], 1.34 [95% confidence interval {CI}, 1.01-1.79]), those requiring any respiratory support except mechanical ventilation (aRR, 1.41 [95% CI, 1.05-1.90]), or those requiring invasive mechanical ventilation (aRR, 1.83 [95% CI, 1.36-2.47]) (compared with no respiratory support). The presence of a pulmonary comorbidity other than asthma (aRR, 2.31 [95% CI, 1.15-4.62]) was associated with bacterial coinfection. Conclusions: Community-onset bacterial coinfection in children with critical COVID-19 is infrequent, but empiric antibiotics are commonly prescribed. These findings inform antimicrobial use and support rapid de-escalation when evaluation shows coinfection is unlikely.

Life-Threatening Complications of Influenza vs Coronavirus Disease 2019 (COVID-19) in US Children.

BACKGROUND: Clinical differences between critical illness from influenza infection vs coronavirus disease 2019 (COVID-19) have not been well characterized in pediatric patients. METHODS: We compared demographics, clinical characteristics, and outcomes of US children (aged 8 months to 17 years) admitted to the intensive care or high-acuity unit with influenza or COVID-19. Using mixed-effects models, we assessed the odds of death or requiring life support for influenza vs COVID-19 after adjustment for age, sex, race and Hispanic origin, and underlying conditions including obesity. RESULTS: Children with influenza (n = 179) were younger than those with COVID-19 (n = 381; median, 5.2 years vs 13.8 years), less likely to be non-Hispanic Black (14.5% vs 27.6%) or Hispanic (24.0% vs 36.2%), and less likely to have ≥1 underlying condition (66.4% vs 78.5%) or be obese (21.4% vs 42.2%), and a shorter hospital stay (median, 5 days vs 7 days). They were similarly likely to require invasive mechanical ventilation (both 30.2%), vasopressor support (19.6% and 19.9%), or extracorporeal membrane oxygenation (2.2% and 2.9%). Four children with influenza (2.2%) and 11 children with COVID-19 (2.9%) died. The odds of death or requiring life support in children with influenza vs COVID-19 were similar (adjusted odds ratio, 1.30; 95% confidence interval, .78-2.15; P = .32). CONCLUSIONS: Despite differences in demographics and clinical characteristics of children with influenza or COVID-19, the frequency of life-threatening complications was similar. Our findings highlight the importance of implementing prevention measures to reduce transmission and disease severity of influenza and COVID-19.

Tachyarrhythmias During Hospitalization for COVID-19 or Multisystem Inflammatory Syndrome in Children and Adolescents.

Background Cardiac complications related to COVID-19 in children and adolescents include ventricular dysfunction, myocarditis, coronary artery aneurysm, and bradyarrhythmias, but tachyarrhythmias are less understood. The goal of this study was to evaluate the frequency, characteristics, and outcomes of children and adolescents experiencing tachyarrhythmias while hospitalized for acute severe COVID-19 or multisystem inflammatory syndrome in children. Methods and Results This study involved a case series of 63 patients with tachyarrhythmias reported in a public health surveillance registry of patients aged <21 years hospitalized from March 15, 2020, to December 31, 2021, at 63 US hospitals. Patients with tachyarrhythmias were compared with patients with severe COVID-19-related complications without tachyarrhythmias. Tachyarrhythmias were reported in 22 of 1257 patients (1.8%) with acute COVID-19 and 41 of 2343 (1.7%) patients with multisystem inflammatory syndrome in children. They included supraventricular tachycardia in 28 (44%), accelerated junctional rhythm in 9 (14%), and ventricular tachycardia in 38 (60%); >1 type was reported in 12 (19%). Registry patients with versus without tachyarrhythmia were older (median age, 15.4 [range, 10.4-17.4] versus 10.0 [range, 5.4-14.8] years) and had higher illness severity on hospital admission. Intervention for treatment of tachyarrhythmia was required in 37 (59%) patients and included antiarrhythmic medication (n=31, 49%), electrical cardioversion (n=11, 17%), cardiopulmonary resuscitation (n=8, 13%), and extracorporeal membrane oxygenation (n=9, 14%). Patients with tachyarrhythmias had longer hospital length of stay than those who did not, and 9 (14%) versus 77 (2%) died. Conclusions Tachyarrhythmias were a rare complication of acute severe COVID-19 and multisystem inflammatory syndrome in children and adolescents and were associated with worse clinical outcomes, highlighting the importance of close monitoring, aggressive treatment, and postdischarge care.

A Description of COVID-19-Directed Therapy in Children Admitted to US Intensive Care Units 2020.

BACKGROUND: It is unclear how acute coronavirus disease 2019 (COVID-19)-directed therapies are used in children with life-threatening COVID-19 in US hospitals. We described characteristics of children hospitalized in the intensive care unit or step-down unit (ICU/SDU) who received COVID-19-directed therapies and the specific therapies administered. METHODS: Between March 15, 2020 and December 27, 2020, children <18 years of age in the ICU/SDU with acute COVID-19 at 48 pediatric hospitals in the United States were identified. Demographics, laboratory values, and clinical course were compared in children who did and did not receive COVID-19-directed therapies. Trends in COVID-19-directed therapies over time were evaluated. RESULTS: Of 424 children in the ICU/SDU, 235 (55%) received COVID-19-directed therapies. Children who received COVID-19-directed therapies were older than those who did not receive COVID-19-directed therapies (13.3 [5.6-16.2] vs 9.8 [0.65-15.9] years), more had underlying medical conditions (188 [80%] vs 104 [55%]; difference = 25% [95% CI: 16% to 34%]), more received respiratory support (206 [88%] vs 71 [38%]; difference = 50% [95% CI: 34% to 56%]), and more died (8 [3.4%] vs 0). Of the 235 children receiving COVID-19-directed therapies, 172 (73%) received systemic steroids and 150 (64%) received remdesivir, with rising remdesivir use over the study period (14% in March/April to 57% November/December). CONCLUSION: Despite the lack of pediatric data evaluating treatments for COVID-19 in critically ill children, more than half of children requiring intensive or high acuity care received COVID-19-directed therapies.

Frequency, Characteristics and Complications of COVID-19 in Hospitalized Infants.

BACKGROUND: Previous studies of severe acute respiratory syndrome coronavirus 2 infection in infants have incompletely characterized factors associated with severe illness or focused on infants born to mothers with coronavirus disease 2019 (COVID-19). Here we highlight demographics, clinical characteristics and laboratory values that differ between infants with and without severe acute COVID-19. METHODS: Active surveillance was performed by the Overcoming COVID-19 network to identify children and adolescents with severe acute respiratory syndrome coronavirus 2-related illness hospitalized at 62 sites in 31 states from March 15 to December 27, 2020. We analyzed patients >7 days to <1 year old hospitalized with symptomatic acute COVID-19. RESULTS: We report 232 infants >7 days to <1 year of age hospitalized with acute symptomatic COVID-19 from 37 US hospitals in our cohort from March 15 to December 27, 2020. Among 630 cases of severe COVID-19 in patients >7 days to <18 years old, 128 (20.3%) were infants. In infants with severe illness from the entire study period, the median age was 2 months, 66% were from racial and ethnic minority groups, 66% were previously healthy, 73% had respiratory complications, 13% received mechanical ventilation and <1% died. CONCLUSIONS: Infants accounted for over a fifth of children <18 years of age hospitalized for severe acute COVID-19, commonly manifesting with respiratory symptoms and complications. Although most infants hospitalized with COVID-19 did not suffer significant complications, longer term outcomes remain unclear. Notably, 75% of infants with severe disease were <6 months of age in this cohort study period, which predated maternal COVID-19 vaccination, underscoring the importance of maternal vaccination for COVID-19 in protecting the mother and infant.

Data-driven clustering identifies features distinguishing multisystem inflammatory syndrome from acute COVID-19 in children and adolescents.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) consensus criteria were designed for maximal sensitivity and therefore capture patients with acute COVID-19 pneumonia. METHODS: We performed unsupervised clustering on data from 1,526 patients (684 labeled MIS-C by clinicians) <21 years old hospitalized with COVID-19-related illness admitted between 15 March 2020 and 31 December 2020. We compared prevalence of assigned MIS-C labels and clinical features among clusters, followed by recursive feature elimination to identify characteristics of potentially misclassified MIS-C-labeled patients. FINDINGS: Of 94 clinical features tested, 46 were retained for clustering. Cluster 1 patients (N = 498; 92% labeled MIS-C) were mostly previously healthy (71%), with mean age 7·2 ± 0·4 years, predominant cardiovascular (77%) and/or mucocutaneous (82%) involvement, high inflammatory biomarkers, and mostly SARS-CoV-2 PCR negative (60%). Cluster 2 patients (N = 445; 27% labeled MIS-C) frequently had pre-existing conditions (79%, with 39% respiratory), were similarly 7·4 ± 2·1 years old, and commonly had chest radiograph infiltrates (79%) and positive PCR testing (90%). Cluster 3 patients (N = 583; 19% labeled MIS-C) were younger (2·8 ± 2·0 y), PCR positive (86%), with less inflammation. Radiographic findings of pulmonary infiltrates and positive SARS-CoV-2 PCR accurately distinguished cluster 2 MIS-C labeled patients from cluster 1 patients. INTERPRETATION: Using a data driven, unsupervised approach, we identified features that cluster patients into a group with high likelihood of having MIS-C. Other features identified a cluster of patients more likely to have acute severe COVID-19 pulmonary disease, and patients in this cluster labeled by clinicians as MIS-C may be misclassified. These data driven phenotypes may help refine the diagnosis of MIS-C.

Multisystem Inflammatory Syndrome in Children - Initial Therapy and Outcomes.

BACKGROUND: The assessment of real-world effectiveness of immunomodulatory medications for multisystem inflammatory syndrome in children (MIS-C) may guide therapy. METHODS: We analyzed surveillance data on inpatients younger than 21 years of age who had MIS-C and were admitted to 1 of 58 U.S. hospitals between March 15 and October 31, 2020. The effectiveness of initial immunomodulatory therapy (day 0, indicating the first day any such therapy for MIS-C was given) with intravenous immune globulin (IVIG) plus glucocorticoids, as compared with IVIG alone, was evaluated with propensity-score matching and inverse probability weighting, with adjustment for baseline MIS-C severity and demographic characteristics. The primary outcome was cardiovascular dysfunction (a composite of left ventricular dysfunction or shock resulting in the use of vasopressors) on or after day 2. Secondary outcomes included the components of the primary outcome, the receipt of adjunctive treatment (glucocorticoids in patients not already receiving glucocorticoids on day 0, a biologic, or a second dose of IVIG) on or after day 1, and persistent or recurrent fever on or after day 2. RESULTS: A total of 518 patients with MIS-C (median age, 8.7 years) received at least one immunomodulatory therapy; 75% had been previously healthy, and 9 died. In the propensity-score-matched analysis, initial treatment with IVIG plus glucocorticoids (103 patients) was associated with a lower risk of cardiovascular dysfunction on or after day 2 than IVIG alone (103 patients) (17% vs. 31%; risk ratio, 0.56; 95% confidence interval [CI], 0.34 to 0.94). The risks of the components of the composite outcome were also lower among those who received IVIG plus glucocorticoids: left ventricular dysfunction occurred in 8% and 17% of the patients, respectively (risk ratio, 0.46; 95% CI, 0.19 to 1.15), and shock resulting in vasopressor use in 13% and 24% (risk ratio, 0.54; 95% CI, 0.29 to 1.00). The use of adjunctive therapy was lower among patients who received IVIG plus glucocorticoids than among those who received IVIG alone (34% vs. 70%; risk ratio, 0.49; 95% CI, 0.36 to 0.65), but the risk of fever was unaffected (31% and 40%, respectively; risk ratio, 0.78; 95% CI, 0.53 to 1.13). The inverse-probability-weighted analysis confirmed the results of the propensity-score-matched analysis. CONCLUSIONS: Among children and adolescents with MIS-C, initial treatment with IVIG plus glucocorticoids was associated with a lower risk of new or persistent cardiovascular dysfunction than IVIG alone. (Funded by the Centers for Disease Control and Prevention.).

Neurologic Involvement in Children and Adolescents Hospitalized in the United States for COVID-19 or Multisystem Inflammatory Syndrome.

Importance: Coronavirus disease 2019 (COVID-19) affects the nervous system in adult patients. The spectrum of neurologic involvement in children and adolescents is unclear. Objective: To understand the range and severity of neurologic involvement among children and adolescents associated with COVID-19. Setting, Design, and Participants: Case series of patients (age <21 years) hospitalized between March 15, 2020, and December 15, 2020, with positive severe acute respiratory syndrome coronavirus 2 test result (reverse transcriptase-polymerase chain reaction and/or antibody) at 61 US hospitals in the Overcoming COVID-19 public health registry, including 616 (36%) meeting criteria for multisystem inflammatory syndrome in children. Patients with neurologic involvement had acute neurologic signs, symptoms, or diseases on presentation or during hospitalization. Life-threatening involvement was adjudicated by experts based on clinical and/or neuroradiologic features. Exposures: Severe acute respiratory syndrome coronavirus 2. Main Outcomes and Measures: Type and severity of neurologic involvement, laboratory and imaging data, and outcomes (death or survival with new neurologic deficits) at hospital discharge. Results: Of 1695 patients (909 [54%] male; median [interquartile range] age, 9.1 [2.4-15.3] years), 365 (22%) from 52 sites had documented neurologic involvement. Patients with neurologic involvement were more likely to have underlying neurologic disorders (81 of 365 [22%]) compared with those without (113 of 1330 [8%]), but a similar number were previously healthy (195 [53%] vs 723 [54%]) and met criteria for multisystem inflammatory syndrome in children (126 [35%] vs 490 [37%]). Among those with neurologic involvement, 322 (88%) had transient symptoms and survived, and 43 (12%) developed life-threatening conditions clinically adjudicated to be associated with COVID-19, including severe encephalopathy (n = 15; 5 with splenial lesions), stroke (n = 12), central nervous system infection/demyelination (n = 8), Guillain-Barré syndrome/variants (n = 4), and acute fulminant cerebral edema (n = 4). Compared with those without life-threatening conditions (n = 322), those with life-threatening neurologic conditions had higher neutrophil-to-lymphocyte ratios (median, 12.2 vs 4.4) and higher reported frequency of D-dimer greater than 3 µg/mL fibrinogen equivalent units (21 [49%] vs 72 [22%]). Of 43 patients who developed COVID-19-related life-threatening neurologic involvement, 17 survivors (40%) had new neurologic deficits at hospital discharge, and 11 patients (26%) died. Conclusions and Relevance: In this study, many children and adolescents hospitalized for COVID-19 or multisystem inflammatory syndrome in children had neurologic involvement, mostly transient symptoms. A range of life-threatening and fatal neurologic conditions associated with COVID-19 infrequently occurred. Effects on long-term neurodevelopmental outcomes are unknown.

Characteristics and Outcomes of US Children and Adolescents With Multisystem Inflammatory Syndrome in Children (MIS-C) Compared With Severe Acute COVID-19.

Importance: Refinement of criteria for multisystem inflammatory syndrome in children (MIS-C) may inform efforts to improve health outcomes. Objective: To compare clinical characteristics and outcomes of children and adolescents with MIS-C vs those with severe coronavirus disease 2019 (COVID-19). Setting, Design, and Participants: Case series of 1116 patients aged younger than 21 years hospitalized between March 15 and October 31, 2020, at 66 US hospitals in 31 states. Final date of follow-up was January 5, 2021. Patients with MIS-C had fever, inflammation, multisystem involvement, and positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase-polymerase chain reaction (RT-PCR) or antibody test results or recent exposure with no alternate diagnosis. Patients with COVID-19 had positive RT-PCR test results and severe organ system involvement. Exposure: SARS-CoV-2. Main Outcomes and Measures: Presenting symptoms, organ system complications, laboratory biomarkers, interventions, and clinical outcomes. Multivariable regression was used to compute adjusted risk ratios (aRRs) of factors associated with MIS-C vs COVID-19. Results: Of 1116 patients (median age, 9.7 years; 45% female), 539 (48%) were diagnosed with MIS-C and 577 (52%) with COVID-19. Compared with patients with COVID-19, patients with MIS-C were more likely to be 6 to 12 years old (40.8% vs 19.4%; absolute risk difference [RD], 21.4% [95% CI, 16.1%-26.7%]; aRR, 1.51 [95% CI, 1.33-1.72] vs 0-5 years) and non-Hispanic Black (32.3% vs 21.5%; RD, 10.8% [95% CI, 5.6%-16.0%]; aRR, 1.43 [95% CI, 1.17-1.76] vs White). Compared with patients with COVID-19, patients with MIS-C were more likely to have cardiorespiratory involvement (56.0% vs 8.8%; RD, 47.2% [95% CI, 42.4%-52.0%]; aRR, 2.99 [95% CI, 2.55-3.50] vs respiratory involvement), cardiovascular without respiratory involvement (10.6% vs 2.9%; RD, 7.7% [95% CI, 4.7%-10.6%]; aRR, 2.49 [95% CI, 2.05-3.02] vs respiratory involvement), and mucocutaneous without cardiorespiratory involvement (7.1% vs 2.3%; RD, 4.8% [95% CI, 2.3%-7.3%]; aRR, 2.29 [95% CI, 1.84-2.85] vs respiratory involvement). Patients with MIS-C had higher neutrophil to lymphocyte ratio (median, 6.4 vs 2.7, P < .001), higher C-reactive protein level (median, 152 mg/L vs 33 mg/L; P < .001), and lower platelet count (<150 ×103 cells/µL [212/523 {41%} vs 84/486 {17%}, P < .001]). A total of 398 patients (73.8%) with MIS-C and 253 (43.8%) with COVID-19 were admitted to the intensive care unit, and 10 (1.9%) with MIS-C and 8 (1.4%) with COVID-19 died during hospitalization. Among patients with MIS-C with reduced left ventricular systolic function (172/503, 34.2%) and coronary artery aneurysm (57/424, 13.4%), an estimated 91.0% (95% CI, 86.0%-94.7%) and 79.1% (95% CI, 67.1%-89.1%), respectively, normalized within 30 days. Conclusions and Relevance: This case series of patients with MIS-C and with COVID-19 identified patterns of clinical presentation and organ system involvement. These patterns may help differentiate between MIS-C and COVID-19.

The Impact of Preintubation Noninvasive Ventilation on Outcomes in Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVES: There is evidence that noninvasive ventilation decreases the need for invasive mechanical ventilation. However, children with pediatric acute respiratory distress syndrome who fail noninvasive ventilation may have worse outcomes than those who are intubated without exposure to noninvasive ventilation. Our objective was to evaluate the impact of preintubation noninvasive ventilation on children with pediatric acute respiratory distress syndrome. DESIGN: Secondary analysis of data from the Randomized Evaluation of Sedation Titration for Respiratory Failure trial. SETTING: Thirty-one PICUs in the United States. PATIENTS: Children 2 weeks to 17 years old with pediatric acute respiratory distress syndrome receiving invasive mechanical ventilation, excluding those admitted with tracheostomies. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 2,427 subjects receiving invasive mechanical ventilation, preintubation noninvasive ventilation was used in 995 (41%). Compared with subjects without preintubation noninvasive ventilation use, subjects with preintubation noninvasive ventilation use were more likely to have a history of seizures (10% vs 8%; p = 0.04) or cancer (11% vs 6%; p < 0.001) and have moderate or severe pediatric acute respiratory distress syndrome by the end of their first full day of invasive mechanical ventilation (68% vs 60%; p < 0.001). Adjusting for age, severity of illness on PICU admission, and baseline functional status, preintubation noninvasive ventilation use resulted in longer invasive mechanical ventilation duration (median 7.0 vs 6.0 d), longer PICU (10.8 vs 8.9 d), and hospital (17 vs 14 d) lengths of stay, and higher 28-day (5% vs 4%) and 90-day (8% vs 5%) inhospital mortalities (all comparisons p < 0.001). Longer duration of noninvasive ventilation before intubation was associated with worse outcomes. CONCLUSIONS: In children with pediatric acute respiratory distress syndrome, preintubation noninvasive ventilation use is associated with worse outcomes when compared with no preintubation noninvasive ventilation use. These data can be used to inform the design of clinical studies to evaluate best noninvasive ventilation practices in children with pediatric acute respiratory distress syndrome.

Evaluation of Mannose Binding Lectin Gene Variants in Pediatric Influenza Virus-Related Critical Illness.

Background: Mannose-binding lectin (MBL) is an innate immune protein with strong biologic plausibility for protecting against influenza virus-related sepsis and bacterial co-infection. In an autopsy cohort of 105 influenza-infected young people, carriage of the deleterious MBL gene MBL2_Gly54Asp("B") mutation was identified in 5 of 8 individuals that died from influenza-methicillin-resistant Staphylococcus aureus (MRSA) co-infection. We evaluated MBL2 variants known to influence MBL levels with pediatric influenza-related critical illness susceptibility and/or severity including with bacterial co-infections. Methods: We enrolled children and adolescents with laboratory-confirmed influenza infection across 38 pediatric intensive care units from November 2008 to June 2016. We sequenced MBL2 "low-producer" variants rs11003125("H/L"), rs7096206("Y/X"), rs1800450Gly54Asp("B"), rs1800451Gly57Glu("C"), rs5030737Arg52Cys("D") in patients and biologic parents. We measured serum levels and compared complement activity in low-producing homozygotes ("B/B," "C/C") to HYA/HYA controls. We used a population control of 1,142 healthy children and also analyzed family trios (PBAT/HBAT) to evaluate disease susceptibility, and nested case-control analyses to evaluate severity. Results: We genotyped 420 patients with confirmed influenza-related sepsis: 159 (38%) had acute lung injury (ALI), 165 (39%) septic shock, and 30 (7%) died. Although bacterial co-infection was diagnosed in 133 patients (32%), only MRSA co-infection (n = 33, 8% overall) was associated with death (p < 0.0001), present in 11 of 30 children that died (37%). MBL2 variants predicted serum levels and complement activation as expected. We found no association between influenza-related critical illness susceptibility and MBL2 variants using family trios (633 biologic parents) or compared to population controls. MBL2 variants were not associated with admission illness severity, septic shock, ALI, or bacterial co-infection diagnosis. Carriage of low-MBL producing MBL2 variants was not a risk factor for mortality, but children that died did have higher carriage of one or more B alleles (OR 2.3; p = 0.007), including 7 of 11 with influenza MRSA-related death (vs. 2 of 22 survivors: OR 14.5, p = 0.0002). Conclusions:MBL2 variants that decrease MBL levels were not associated with susceptibility to pediatric influenza-related critical illness or with multiple measures of critical illness severity. We confirmed a prior report of higher B allele carriage in a relatively small number of young individuals with influenza-MRSA associated death.

Lower respiratory tract viral infections in pediatric abdominal organ transplant recipients: a single hospital inpatient cohort study.

Respiratory viral infections are a major cause of morbidity and mortality in solid organ transplant recipients. Early detection of a viral etiology of a LRTI in a febrile transplant recipient can theoretically reduce the use of antibiotics, trigger modification of immunosuppression and prompt appropriate isolation procedures to reduce nosocomial infections. We retrospectively evaluated pediatric abdominal organ transplant recipients hospitalized with respiratory illnesses to determine the viral pathogens identified by various methods including multiplex RT-PCR performed on nasopharyngeal or endotracheal aspirates. Among 30 symptomatic subjects (median age, 2.5 yr) evaluated using this methodology, 25 (83%) were positive for at least one virus. Rhinovirus was the most frequently identified virus (14 subjects). RSV was identified in five subjects with associated mortality of 40%. Parainfluenza, influenza, metapneumovirus, and adenovirus were also identified. This study indicates that rhinovirus is a significant cause of morbidity in this single center cohort of pediatric abdominal organ transplant recipients.

Nonsurgical care of intestinal and multivisceral transplant recipients: a review for the intensivist.

Intestinal and multivisceral transplantation has evolved from an experimental procedure to the treatment of choice for patients with irreversible intestinal failure and serious complications related to long-term parenteral nutrition. Increased numbers of transplant recipients and improved survival rates have led to an increased prevalence of this patient population in intensive care units. Management of intestinal and multivisceral transplant recipients is uniquely challenging because of complications arising from the high incidence of transplant rejection and its treatment. Long-term comorbidities, such as diabetes, hypertension, chronic kidney failure, and neurological sequelae, also develop in this patient population as survival improves. This article is intended for intensivists who provide care to critically ill recipients of intestinal and multivisceral transplants. As perioperative care of intestinal/multivisceral transplant recipients has been described elsewhere, this review focuses on common nonsurgical complications with which one should be familiar in order to provide optimal care. The article is both a review of the current literature on multivisceral and isolated intestinal transplantation as well as a reflection of our own experience at the University of Miami.

Adenosine receptor antagonism in acute tacrolimus toxicity.

BACKGROUND: Calcineurin inhibitors induce renal vasoconstriction and oliguria during acute toxicity. We previously demonstrated that the non-specific adenosine receptor antagonist theophylline improved glomerular filtration rate (GFR) and renal blood flow in the setting of acute tacrolimus (TAC) toxicity. This study was undertaken to determine which of the known adenosine receptor subtypes is responsible for the observed effect of theophylline. METHODS: The GFR was measured by clearance of 51Cr-EDTA in anaesthetized, instrumented Sprague-Dawley rats at three time points: at baseline, 60 min after intravenous administration of TAC (0.05 mg/kg) or vehicle (V) and at 100 min after TAC or V. Either DMSO (n = 5) or one of the three available specific adenosine receptor subtype antagonists 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 2 mg/kg, n = 5), a selective A1 receptor antagonist, 8-(3-chlorostyryl) caffeine (CSC, 2 mg/kg, n = 4), a selective A2a receptor antagonist and 3-ethyl-5-benzyl-2-methyl-4-phenylethynyl-6-phenyl-1,4-dihydropyridine-3,5 dicarboxylate (MRS1191, 1 mg/kg, n = 5), a selective A3 receptor antagonist, was administered intra-peritoneally prior to the final GFR measurement. Repeated measures analysis of variance was used to detect differences between groups (P < 0.05). RESULTS: Measured GFR declined by 30% from baseline 60 min after TAC. In DMSO treated animals, GFR decreased 51% from baseline at 100 min after TAC, but increased 45% from baseline at 100 min after TAC + MRS1191. CONCLUSIONS: Only administration of the A3 adenosine antagonist increased GFR following TAC, suggesting that this receptor mediates the effect of theophylline on GFR.

Reversal of oliguric tacrolimus nephrotoxicity in children.

BACKGROUND: Acute tacrolimus toxicity is manifest by oliguria and elevated serum creatinine. Various vasoregulatory molecules have been implicated in calcineurin inhibitor-mediated nephrotoxicity, including calcium, adenosine and endothelin. Theophylline (THEO), a non-specific adenosine-receptor antagonist prevents renal dysfunction from various nephrotoxins which mediate vasoconstriction. In the setting of acute tacrolimus toxicity, we demonstrated that administration of THEO along with a loop diuretic (LD) enhanced diuresis. This randomized, controlled trial was undertaken to confirm these earlier findings under more rigorous conditions. METHODS: Children with non-renal visceral transplant(s) and evidence of tacrolimus nephrotoxicity oliguria with a 25% increase in serum creatinine concentration from baseline, a whole blood tacrolimus concentration >20 ng/dl and oliguria resistant to therapy with a LD were randomized to receive either THEO (n = 10) or normal saline placebo (n = 8). Using pre and post (6 h) timed urine collections and coincident plasma concentrations the following were measured or calculated: urine flow rate, net fluid balance, creatinine clearance, fractional excretion of chloride, free water clearance and distal delivery of chloride. RESULTS: These patients had markedly impaired creatinine clearance at the onset of tacrolimus toxicity. Urine flow increased in the LD + THEO group by 110% over baseline, but was unchanged in the LD + NS group. An increase in creatinine clearance did not reach statistical significance (P = 0.09). Fractional excretion of chloride and distal solute delivery increased after THEO treatment. CONCLUSIONS: THEO induced a solute diuresis during furosemide-resistant oliguric tacrolimus toxicity in paediatric patients with a trend towards improved renal function.

Open lung biopsy in pediatric patients with respiratory failure after abdominal transplantation.

To understand the utility of open lung biopsy (OLB) in the evaluation of respiratory failure in pediatric abdominal organ transplant we reviewed the records of nine children in this patient population who underwent an OLB. Eight of nine patients had undergone a previous non-diagnostic bronchoalveolar lavage. Biopsies were performed at the bedside in the pediatric intensive care unit and tissue was processed by the Department of Pathology with special stains for infectious agents. There were no significant complications of OLB. A specific treatable etiology was identified in four patients (respiratory syncytial virus, adenovirus, graft-vs.-host disease and post-transplant lymphoproliferative disease), leading to a change in therapy and survival in two. Overall survival was 44%. Given the low morbidity, OLB as performed in this study appears appropriate in this patient population.

Intestinal transplantation in children: a summary of clinical outcomes and prognostic factors in 108 patients from a single center.

We performed 124 intestinal transplants on 108 children (median age, 1.5 years) since 1994. Initial graft types included isolated intestine (I) (n=26), liver and intestine (LI) (n=26), multivisceral (MV) (n=50), and multivisceral without liver (MMV) (n=6). Four groups were defined by type of induction therapy: none, OKT3, or cyclophosphamide (August 1994-December 1997, n=25), early experience with daclizumab (January 1998-December 2000, n=26), recent experience with daclizumab (January 2001-April 2004, n=40), and Campath-1H (January 2001-April 2004, n=17). Actuarial patient survival at 1 year for groups 1-4 was 44%+/-10%, 54%+/-10%, 83%+/-6%, and 41%+/-12%, respectively, with group 3 having the most favorable survival (P=0.0004). Using Cox stepwise regression, the hazard rate of developing severe rejection was significantly higher in patients with transplant type I or LI (P=0.0002), with no difference between these groups (P=0.24) but a significantly higher rate for LI versus MV (P=0.005). Three factors associated with improved patient survival were recipient of MV or MMV (P=0.008), age at transplantation greater than 1 year (P=0.01), and use of daclizumab (P=0.0006). Cause-specific hazard analysis revealed a decreased rate of rejection-related mortality for recipients of MV or MMV (P=0.0007), whereas age greater than 1 year indicated a lower rate of infection-related mortality (P=0.0009). Pediatric intestinal transplantation provides an increasingly realistic chance of survival, particularly with the more recent use of daclizumab and multivisceral transplantation. A protective effect of multivisceral transplantation appears to exist with respect to the development of severe rejection.

Reversal of acute tacrolimus-induced renal vasoconstriction by theophylline in rats.

OBJECTIVE: To determine whether theophylline, a nonselective adenosine receptor antagonist and phosphodiesterase inhibitor, reverses the acute declines in renal blood flow and glomerular filtration rate induced by high-dose tacrolimus in rats. DESIGN: Prospective, randomized, placebo-controlled experimental study. SETTING: University-based basic science research laboratory. SUBJECTS: Adult male Sprague-Dawley rats. INTERVENTIONS: After mechanical ventilation and instrumentation under isoflurane and nitrous oxide anesthesia, animals received either tacrolimus 0.5 mg/kg intravenously or vehicle and 1 hr later either theophylline 4 mg/kg intravenously or vehicle. MEASUREMENTS AND MAIN RESULTS: By using radiolabeled microspheres, renal blood flow was measured in three groups: control (n = 5), tacrolimus plus vehicle (n = 6), and tacrolimus plus theophylline (n = 6) at four time points-baseline and 60, 75, and 90 mins after tacrolimus or vehicle (the latter two time points being 15 and 30 mins after theophylline or vehicle, respectively). Whole blood tacrolimus and serum theophylline concentrations were measured. In a separate group of animals, by using (51)Cr-EDTA, glomerular filtration rate was measured in two groups: tacrolimus plus vehicle (n = 5) and tacrolimus plus theophylline (n = 5) at baseline and over two consecutive 20-min time periods beginning 61 mins posttacrolimus. Urine flow rate also was measured. Following tacrolimus, both renal blood flow and glomerular filtration rate declined in parallel by approximately 33% and 50% from baseline after 75 and 90 mins, respectively (p <.05 by two-way repeated-measures analysis of variance). Theophylline completely reversed these tacrolimus-induced decreases in renal blood flow and glomerular filtration rate. Urine flow rate also increased in response to theophylline. CONCLUSIONS: Low-dose theophylline reverses tacrolimus-induced declines in renal blood flow and glomerular filtration rate observed in an acute model of tacrolimus toxicity. Theophylline's effect in chronic toxicity remains to be determined.