About

Julie C Fitzgerald, MD, PhD, MSCE, is an Associate Professor of Anesthesiology and Critical Care at the Hospital of the University of Pennsylvania and the Children's Hospital of Philadelphia. She serves as an Attending Physician in Pediatric Critical Care at the Children's Hospital of Philadelphia, where she also co-directs the Pediatric Sepsis Program, a creation funded through a CHOP Department of Pediatrics Chair's Initiative. Additionally, she holds the position of Associate Chief of Research in the Division of Critical Care Medicine at the Children's Hospital of Philadelphia and is the Faculty Director of the CTSA@CHOP Center for Phenomic Science Clinical Research Unit. Her educational background includes a BA in Biology from the University of Pennsylvania, obtained in 1997, a PhD in Cell & Molecular Biology from the same institution in 2005, an MD from the University of Pennsylvania Perelman School of Medicine in 2005, an MSCE in Clinical Epidemiology from the University of Pennsylvania in 2017, and a Certification in Research Mentor Training from the University of Pennsylvania Perelman School of Medicine in 2022.

Research topics

• Medicine
• Internal medicine
• Immunology
• Pathology
• Intensive care medicine
• Cardiology
• Biology
• Oncology
• Cell biology
• Radiology
• Virology

Selected publications

• Balanced Fluid or 0.9% Saline in Children Treated for Septic Shock

  New England Journal of Medicine · 2026-04-23 · 1 citations

  articleOpen access

  BACKGROUND: Whether treatment with balanced crystalloid fluid leads to better outcomes than 0.9% saline in children treated for septic shock is debated. METHODS: In this pragmatic clinical trial conducted at 47 emergency departments in five countries, patients (2 months to <18 years of age) with suspected septic shock and abnormal perfusion were randomly assigned to receive fluid resuscitation with either balanced fluid or 0.9% saline for up to 48 hours. The primary outcome was a major adverse kidney event (a composite of death, new renal-replacement therapy, or persistent kidney dysfunction) at 30 days after enrollment or hospital discharge, whichever occurred first. RESULTS: Of 9041 enrolled patients, 277 (6.1%) in the balanced-fluid group and 282 (6.2%) in the 0.9%-saline group withdrew from the trial, leaving 4235 and 4247 patients, respectively, for analysis. A primary-outcome event occurred in 137 patients (3.4%) in the balanced-fluid group and in 124 (3.0%) in the 0.9%-saline group (difference, 0.4 percentage points; 95% confidence interval [CI], -0.5 to 1.3; risk ratio, 1.10; 95% CI, 0.88 to 1.40; P = 0.85). The median number of hospital-free days during 28 days after enrollment was 23 (interquartile range, 19 to 25) in both groups. Hyperchloremia occurred in 868 patients (31.4%) in the balanced-fluid group and in 1383 (49.0%) in the 0.9%-saline group; hypernatremia in 52 (1.8%) and 89 (3.1%), respectively; and hyperlactatemia in 260 (19.8%) and 228 (16.7%). No differences in other safety outcomes or adverse events were seen. CONCLUSIONS: Among children treated for septic shock, no significant difference was seen in the incidence of death, new renal-replacement therapy, or persistent kidney dysfunction when fluid resuscitation was administered with balanced fluid as compared with 0.9% saline. (Funded by Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; PRoMPT BOLUS ClinicalTrials.gov number, NCT04102371.).

  PublisherOA PDFDOI

• External Validation, Molecular Signatures, and Therapeutic Relevance of Pediatric Sepsis-Associated Acute Kidney Injury Subphenotypes

  Critical Care Medicine · 2026-03-30

  article

  OBJECTIVE: Sepsis-associated acute kidney injury (SAKI) is a heterogeneous condition that lacks disease-modifying treatments, and precision medicine approaches are needed. We previously derived two reproducible pediatric SAKI subphenotypes (pSAKI-1 and pSAKI-2) from readily available clinical data. We aimed to externally validate the prognostic relevance of these subphenotypes, evaluate their molecular signatures, and assess for heterogeneity of treatment effect (HTE) across subphenotypes with sepsis therapies. DESIGN: Secondary analysis of an ongoing multicenter, prospective, observational study of children. SETTING: Ten PICUs in the United States from January 2002 to February 2025. PATIENTS: Patients 1 week to 18 years old with early (day 1-2) SAKI. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 871 patients, 665 (76%) were assigned pSAKI-1 and 206 (24%) to pSAKI-2. On day 1-2, the pSAKI-2 cohort had greater severity of illness, including higher acute kidney injury stage and vasoactive burden, lower platelet counts, and higher lactate values and International Normalized Ratios. These pSAKI-2 patients also had uniformly worse outcomes, including independently higher odds of day 7 severe acute kidney injury (adjusted odds ratio [aOR] 3.2; 95% CI, 2.1-4.7; p < 0.001), death (aOR 2.7; 95% CI, 1.6-4.4; p < 0.001), and fewer PICU-free and vasoactive-free days (p < 0.001). The biomarker signature of pSAKI-2 was characterized by greater inflammation, endothelial dysfunction, and hyperreninemia. On propensity score matched (PSM) analysis, pSAKI-1 patients who received corticosteroids had more day 7 severe acute kidney injury (28% vs. 19%, p = 0.023), 2 fewer PICU-free days (p = 0.04) and greater mortality (10% vs. 3.7%, p = 0.008); no differences were seen in pSAKI-2 patients. Although no HTE was identified on PSM analysis for vasopressin, inverse probability treatment weighting analysis demonstrated a significant interaction between subphenotype-, vasopressin- and vasoactive-free days (p = 0.003). CONCLUSIONS: We externally validated the prognostic relevance of two pSAKI subphenotypes derived from readily available data. These subphenotypes have unique biomarker signatures and differential responses to treatment, representing a potential mechanism for bedside enrichment.

  PublisherDOI

• Quantifying “Medical Renal Disease”: A Pediatric Pilot Study Using Ultrasound Radiomics for Differentiating Acute Kidney Injury and Chronic Kidney Disease

  Diagnostics · 2025-08-21 · 1 citations

  articleOpen access

  Background: Differentiating acute kidney injury (AKI) from chronic kidney disease (CKD) in children remains a critical unmet need due to the limitations of current clinical and biochemical markers. Conventional ultrasound lacks the sensitivity to discern subtle parenchymal alterations. This study explores the application of ultrasound radiomics—a novel, non-invasive, and quantitative image analysis method—for distinguishing AKI from CKD in pediatric patients. Methods: In this retrospective cross-sectional pilot study, kidney ultrasound images were obtained from 31 pediatric subjects: 8 with oliguric AKI, 14 with CKD, and 9 healthy controls. Renal parenchyma was manually segmented, and 124 advanced texture features were extracted using the open-source ©PyFeats. Features encompassed multiple categories (e.g., GLCM, GLSZM, WP). Statistical comparisons evaluated intergroup differences. Principal Component Analysis identified the top 10 most informative features, which were used to train supervised machine learning models. Model performance used five-fold cross-validation. Results: Radiomic analysis revealed significant intergroup differences (p &lt; 0.05). CKD cases exhibited increased echogenicity and heterogeneity, particularly in GLCM and GLSZM features, consistent with chronic fibrosis. AKI cases displayed more homogeneous texture, likely reflecting edema or acute inflammation. While echogenicity separated diseased from healthy kidneys, it lacked specificity between AKI and CKD. Among ML models, XGBoost achieved the highest macro-averaged F1 score (0.90), followed closely by SVM and Random Forest, demonstrating strong classification performance. Conclusions: Radiomics-based texture analysis of grayscale ultrasound images effectively differentiated AKI from CKD in this pilot study, offering a promising, non-invasive imaging biomarker for pediatric kidney disease. These preliminary findings justify prospective validation in larger, multicenter cohorts.

  PublisherOA PDFDOI

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

  UNC Libraries · 2025-05-13

  articleOpen access

  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 &gt;7 days to &lt;1 year old hospitalized with symptomatic acute COVID-19. RESULTS: We report 232 infants &gt;7 days to &lt;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 &gt;7 days to &lt;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 &lt;1% died. CONCLUSIONS: Infants accounted for over a fifth of children &lt;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 &lt;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.

  PublisherDOI

• New sepsis-associated morbidity and mortality in pediatric oncology patients

  Frontiers in Oncology · 2025-08-27 · 1 citations

  articleOpen accessSenior authorCorresponding

  Sepsis is a leading cause of morbidity and mortality in children worldwide, yet the development of new morbidity after sepsis has not been clearly defined in high-risk subgroups such as children with cancer. Using the TOPICC (Trichotomous Outcome Prediction in Critical Care) multicenter cohort study dataset, we evaluated whether children with cancer have a higher risk of the composite outcome of death or new morbidity at hospital discharge compared to children without cancer. Among 854 children with sepsis, 88 patients (10.3%) had an underlying cancer diagnosis. Children with cancer were older (median 8.1 vs 3.7 years) and more frequently developed sepsis while in the hospital. The pattern of organ failure differed between groups, with less frequent invasive mechanical ventilation (26.1% vs 49.9%, p &amp;lt;0.001) but more frequent vasoactive infusions (47.7% vs 35.8%, p =0.03) in children with cancer compared to non-oncology patients. Children with cancer had an increased rate of death or new morbidity (22.7% vs 12.1%, p= 0.006) compared to non-oncology patients. New morbidity (defined by ΔFSS score &amp;gt;2 points) occurred in 13.9% of cancer vs 6.9% of non-cancer survivors ( p =0.03), and PICU mortality was similar between groups (10.2% vs 5.6%, p =0.09). Cancer diagnosis was independently associated with higher odds of death or new disability at discharge (adjusted odds ratio 3.71, p &amp;lt;0.001) in multivariable logistic regression, after adjusting for baseline FSS, baseline developmental delay, clinical concern for neurologic injury on PICU admission, and PICU supportive measures. These results suggest that children with cancer who develop sepsis are more likely to experience adverse outcomes at hospital discharge, even after accounting for baseline health and critical illness severity.

  PublisherOA PDFDOI

• Divergence Between Net Fluid and Weight-Based Evaluation in Calculating Cumulative Fluid Balance

  medRxiv · 2025-10-23

  preprintOpen access

  ABSTRACT Objective Although efforts have been made to standardize fluid balance calculations in the intensive care unit (ICU), there is a limited understanding of how different calculation methods relate to one another across an ICU admission. We quantified the agreement between the cumulative fluid balance calculated from fluid intake and output (CFBf) and from serial weights (CFBw) in critically ill children during the first week of ICU admission. Design Retrospective, multicenter, federated observational study. Setting Four pediatric medical-surgical ICUs (PICU) and two pediatric cardiac ICUs (PCICU) from four tertiary care centers. Patients Analysis included 8,895 pediatric patients (&lt;19 years old) representing 12,388 ICU encounters from 2023-2024. Interventions None. Measurements and Main Results A patient’s anchor weight was the weight closest to ICU admission. CFBf and CFBw were calculated at the time of new weight measurements. We assessed agreement between CFBf and CFBw using Bland-Altman analyses, stratified by ICU day and patient subgroups (neonates, early anchor weights [weight on ICU day 0], and encounters with unmeasured urine occurrences). Across all units and subgroups, CFBf exceeded CFBw (mean difference: all patients = 4.7 %CFB, early anchor weight = 4.7 %CFB, neonates = 5.9 %CFB). The mean difference increased significantly over time (days 0–3: 2.7% vs. days 4–7: 8.1%, p&lt;0.05), with greater divergence in neonates and those with early anchor weights. Conclusions CFBf consistently exceeded CFBw across all subgroups, with a greater divergence on ICU days 4-7. Clinicians should understand these differences, prioritizing early and frequent patient weights throughout ICU admission. Future studies should assess each method’s association with patient outcomes to identify the most clinically informative CFB method. Research in Context Cumulative fluid balance (CFB) is calculated by fluid (intake minus output) and weight measurements in pediatric ICU patients, but few studies have directly compared these methods across multiple institutions, unit types, and throughout PICU admission. CFB calculated using fluid measures consistently exceeded weight-based calculations, with divergence increasing later in admission and for patients with anchor weights recorded closer to PICU admissions and neonates. Divergence between CFB methods may reduce CFBf reliability later in the ICU stay, so accurate and frequent PICU weight recordings are essential for reliable fluid balance assessment. At the Bedside This multicenter study demonstrates a consistent positive divergence between CFB calculated by net fluid compared to weight-based calculations across diverse PICU and PCICU populations. Differences between methods diverged later in admission (e.g., after day 3), particularly among neonates and patients with earlier recorded anchor weights, while CFB calculated before the first unmeasured urine differed little from the overall cohort. Clinicians should understand these differences and the factors that influence them, prioritizing early and frequent patient weights throughout ICU admission to recognize when net fluid-based CFB diverges from a weight-based CFB.

  PublisherOA PDFDOI

• Association between Child Opportunity Index and paediatric sepsis recognition and treatment in a large quality improvement collaborative: a retrospective cohort study

  BMJ Quality & Safety · 2025-05-08

  article

  BACKGROUND: The Child Opportunity Index (COI) is a multidimensional measure of US neighbourhood-level conditions needed for healthy development. COI is associated with healthcare delivery and outcomes. Formal quality improvement (QI) may influence the relationship between COI, quality of care and outcomes in children. OBJECTIVE: To assess the association between COI and paediatric sepsis care delivery and outcomes and determine if baseline disparities in care change over time among hospitals in the Improving Pediatric Sepsis Outcomes (IPSO) collaborative. METHODS: Retrospective cohort study of IPSO patients probabilistically linked to the Pediatric Health Information System database from 2017 to 2021. Primary exposure was COI. We estimated differences in the proportions of patients in each COI quintile identified via standardised sepsis recognition protocols (screening tool, huddle documentation and/or order set use) and who received a bundle of recommended care (standardised sepsis recognition, plus bolus <1 hour and antibiotic <3 hours). We further assessed the timeliness of each bundle component and mortality. We evaluated changes in standardised sepsis recognition over time using generalised linear models. RESULTS: 31 260 sepsis cases from 24 hospitals were included. Cross-sectional analysis over the entire study period found patients in the Very High COI quintile were most likely to be identified via standardised recognition protocols and receive IPSO's recommended care bundle (67.7% and 46%, respectively). Over time, standardised sepsis recognition improved for all; the greatest improvements were among inpatients in the Very Low COI quintile. CONCLUSION: Disparities exist in paediatric sepsis care delivery by COI. Over the course of the IPSO collaborative, care improved most for children in the lowest COI quintile. QI collaboratives focused on standardisation and shared learning may reduce disparities.

  PublisherDOI

• Neuropathologic Autopsy Findings in Pediatric Sepsis: A Two-Center, Retrospective Study

  Pediatric Critical Care Medicine · 2025-12-31

  article

  OBJECTIVES: During sepsis, acute brain dysfunction is associated with death and morbidity. However, there are limited data on the pathophysiology of sepsis brain dysfunction. DESIGN: Retrospective cohort study. SETTING: Two quaternary free-standing children's hospitals (University of Pittsburgh Medical Center [UPMC] Children's Hospital of Pittsburgh and Children's Hospital of Philadelphia [CHOP]). SUBJECTS: Sepsis patients with a neuropathological autopsy from 2009 to 2018 at UPMC and 2011-2021 at CHOP. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 57 patients with a median (interquartile range [IQR]) age at admission of 34.5 months (IQR, 9.2-118.0 mo). Overall, 48 of 57 (84%) patients had preexisting comorbidity including: metabolic/genetic disorders (19/57, 33%), immunocompromise (12/57, 21%), and prematurity (12/57, 21%). Almost all patients required inotropes (53/57, 93%) or invasive mechanical ventilation (54/57, 95%). Forty-four percent of patients (25/57) had a cardiac arrest either before or during admission. Almost half of patients had multisite infections (25/57, 44%), with 23 of 25 having a component of bacteremia and four of 25 having a CNS infection. Gross neuropathological findings included edema in 39% (22/57), ventriculomegaly in 39% (22/57), and hemorrhage in 30% (17/57). Microscopic CNS examination results were available for 51 of 57 patients (89%) and the acute/subacute microscopic findings included: neuronal injury in 45% (23/51), acute infarction in 25% (13/51), and white matter necrosis in 25% (13/51). Most patients (49/57, 86%) had at least one acute gross or microscopic finding. In univariate analyses, premortem CNS infections, was associated with edema ( p = 0.001). Also, absence of comorbidities was associated with gross edema ( p = 0.009) and microscopic acute neuronal injury ( p = 0.008), acute infarction ( p = 0.01), and meningitis ( p = 0.004). CONCLUSIONS: In our retrospective neuropathological study of sepsis cases, we found that pathologies were common. While correlations to sepsis survivors cannot be determined, further studies are needed to develop strategies that prevent and treat neuropathological injury.

  PublisherDOI

• 37: DYSREGULATED STAT3 SIGNALING DEFINES A TARGETABLE, HIGH-MORTALITY SUBPHENOTYPE OF PEDIATRIC SEPSIS

  Critical Care Medicine · 2025-01-01

  article
  PublisherDOI

• Assessing Clinical Improvement of Infants Hospitalized for Respiratory Syncytial Virus–Related Critical Illness

  The Journal of Infectious Diseases · 2025-01-06 · 1 citations

  articleOpen access

  BACKGROUND: Pediatric respiratory syncytial virus (RSV)-related acute lower respiratory tract infection (LRTI) commonly requires hospitalization. The Clinical Progression Scale-Pediatrics (CPS-Ped) measures level of respiratory support and degree of hypoxia across a range of disease severity, but it has not been applied in infants hospitalized with severe RSV-LRTI. METHODS: We analyzed data from a prospective surveillance registry of infants hospitalized for RSV-related complications across 39 pediatric intensive care units in the United States from October through December 2022. We assigned CPS-Ped (0 = discharged home at respiratory baseline to 8 = death) at admission and days 2-7, 10, and 14. We identified predictors of clinical improvement (CPS-Ped ≤2 or 3-point decrease) by day 7 using multivariable log-binomial regression models and estimated the sample size (80% power) to detect 15% between-group clinical improvement with CPS-Ped versus hospital length of stay (LOS). RESULTS: Of 585 hospitalized infants, 138 (23.6%) received invasive mechanical ventilation (IMV) and 1 died. Failure to clinically improve by day 7 occurred in 205 (35%) infants and was associated with age <3 months, prematurity, underlying respiratory condition, and IMV in the first 24 hours in the multivariable analysis. The estimated sample size per arm required for detecting a 15% clinical improvement in a potential study was 584 using CPS-Ped clinical improvement versus 2031 for hospital LOS. CONCLUSIONS: CPS-Ped can be used to capture a range of disease severity and track clinical improvement in infants who develop RSV-related critical illness and could be useful for evaluating therapeutic interventions for RSV.

  PublisherOA PDFDOI

Recent grants

• Pediatric septic acute kidney injury: personalizing antibiotic dosing through understanding acute kidney injury risk factors and biomarker profiles

  NIH · $810k · 2020–2025

• Comparative effectiveness of balanced fluids versus normal saline to reduce acute and chronic kidney disease in children with sepsis

  NIH · $15.5M · 2017–2027

Frequent coauthors

• Scott L. Weiss

  Thomas Jefferson University

  349 shared

• Courtney M. Rowan

  Indiana University School of Medicine

  215 shared

• Deyin D. Hsing

  Cornell University

  143 shared

• Fran Balamuth

  Children's Hospital of Philadelphia

  141 shared

• Shira J. Gertz

  Hackensack University Medical Center

  120 shared

• Vinay Nadkarni

  Children's Hospital of Philadelphia

  119 shared

• Lincoln Smith

  111 shared

• Christine Duncan

  Harvard University

  108 shared