Firearm-Related Juvenile Death Rates Correlate With Gun Ownership Rates, Measures of Guns in Circulation, and Leniency of Existing Firearm Laws Among U.S. States.

INTRODUCTION: Firearms now represent the leading cause of death in U.S. children. Therefore, this study aimed to determine if state-level rates of gun ownership, guns in circulation, and strictness of firearm-related laws are related to firearm-related mortality among both juveniles and overall populations. MATERIALS AND METHODS: State firearm mortality rates among the juvenile and overall populations were obtained from 2010 to 2020. The number of weapons registered with the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) and federal firearms licensees for each state were also recorded. Giffords Law Center Scorecard Rankings, a relative measure of the restrictiveness of each state's gun laws, were also collected. Unadjusted linear regressions modeled the relationships between firearm-associated mortality and ATF-registered weapons, federal firearm licensees, Giffords Center rankings, and gun ownership rates. Multivariable (adjusted) analyses were performed to control for poverty, unemployment, and poor mental health. RESULTS: Unadjusted analyses demonstrated that higher gun ownership rates and more lenient gun laws were associated with increased firearm-associated mortality among juveniles. Similarly, these measures as well as increased ATF-registered weapons and ATF federal firearm licensees were associated with increased firearm mortality in the overall population. In the adjusted analyses, more ATF-registered weapons, more ATF federal firearm licensees, higher gun ownership rates, and more lenient firearm laws were associated with increased firearm-related mortality in the overall population, while increased gun ownership and higher Giffords Center rankings were associated with increased firearm-associated mortality in the pediatric population. CONCLUSIONS: To reduce the toll of gun violence in the United States, policymakers should focus on implementing more restrictive firearm laws and reducing the prevalence of guns in their communities.

Single-agent Bevacizumab in the Treatment of Symptomatic Newly Diagnosed and Recurrent/Refractory Pediatric Cervicomedullary Brainstem Low-grade Gliomas: A Single Institutional Experience.

Bevacizumab-based therapies have been utilized as single or combination therapy of refractory/recurrent pediatric low-grade gliomas. Its efficacy for symptomatic cervicomedullary low-grade gliomas (cmLGGs) in the upfront and the recurrent setting is less known. We report our retrospective single institutional experience from 2015 to 2021 with single-agent bevacizumab for symptomatic cmLGG. Six consecutive patients (4 female, ages 2 to 12 y) with newly diagnosed (n=3) and recurrent/refractory (n=3) symptomatic nondisseminated cmLGG (5/6 biopsy-proven, 2 BRAFV600E, 2 BRAF-KIAA1549) were treated with single-agent bevacizumab. All demonstrated radiographic response most pronounced on post-gadolinium T1-weighted magnetic resonance imaging (2 complete, 4 partial) at a median of 8 weeks (range: 2 to 12 wk). Clinical response was seen in all patients with improvement in cranial nerve abnormalities (3 recurrent/refractory, 1 newly diagnosed), strength (2 recurrent/refractory, 2 newly diagnosed), pain (2 recurrent/refractory), and anorexia (1 newly diagnosed). Four patients (2 recurrent/refractory, 2 newly diagnosed) experienced disease progression on subsequent adjunct therapies, 2 of which (the 2 newly diagnosed patients) are currently being rechallenged. At a mean follow-up of 7 months, all patients are clinically stable without disease progression. Single-agent bevacizumab may be effective in the management of symptomatic newly diagnosed and recurrent/refractory cmLGG and warrants further evaluation in a clinical trial setting.

Atypical Molecular Features of Pediatric Tectal Glioma: A Single Institutional Series.

We present 4 children (diagnosed between 1 and 8 y, 3 females and 1 male) with molecularly distinct tectal gliomas (2 KRAS mutant, 1 EGFR mutant, 1 SRGAP3-RAF-1 fusion) that contributes to the growing literature of this uncommonly biopsied tumor. The patient with EGFR R222C mutation had a more severe course, earlier diagnosis, subsequent leptomeningeal metastatic disease, required more aggressive therapies, and died 9 years after diagnosis. Patients with KRAS mutations and SRGAP3-RAF-1 fusion had a more indolent course. Our series expands the molecular phenotype of tectal glioma with the potential for leptomeningeal dissemination. Future studies on establishing genotypic/phenotypic correlation from those who undergo biopsy are needed.

Lessons Learned on a High-Altitude Expedition to Mount Kilimanjaro.

High-altitude expeditions expose teams to particular medical, environmental, and social challenges that can have unintended and severe consequences for crew members. In June 2017, the 9-d Equal Playing Field (EPF) expedition to Mount Kilimanjaro to set a world record for the highest-altitude soccer match ever played demonstrated the variety of challenges that may arise during these types of trips. This trip included a full-length soccer match at 5714 m (18,746 ft), leading to additional challenges for expedition members participating in the athletic event. The EPF medical team identified the challenges that occurred during the expedition and documented the methods used to resolve these challenges in real time. From the challenges faced during the expedition, we describe the lessons learned for future expeditions to Mount Kilimanjaro and other high-altitude environments. Challenges arose with medical tent visibility, medical disqualification, underreporting of medical events, and acute pain management, while anticipated challenges with interpersonal conflict did not occur. The rigorous preparation and anticipation by the EPF medical team prior to expedition departure may have helped mitigate this conflict as well as prevented unintended severe medical events from occurring.

The role of methylation profiling in histologically diagnosed neurocytoma: a case series.

PURPOSE: To highlight the clinical, neuroradiographic, neuropathologic, and molecular features of histologically identified neurocytoma in a pediatric cohort and highlight the evolving use methylation profiling in providing diagnostic clarity in difficult to diagnosis pediatric brain tumors. METHODS: Five consecutive children (ages 9-13, 2 girls 3 boys) were histologically diagnosed with neurocytoma at Rady Children's Hospital San Diego from 2012 to 2018. Clinical and molecular features were analyzed with regards to treatment course and outcome. RESULTS: Presenting symptoms included seizures (n = 2), syncope (n = 1), headache (n = 2), visual disturbances (n = 2) and emesis (n = 2). Tumor location included intraventricular (n = 2), intraventricular with parenchymal spread (n = 1), and extraventricular (n = 2). Magnetic resonance imaging demonstrated reduced diffusivity (2/5), signal abnormality on susceptibility-weighted sequences (3/5), and varying degrees of contrast enhancement (4/5). All patients underwent surgical resection alone. Recurrence occurred in four children that were treated with surgery (4/4), adjuvant radiation (2/4), and chemoradiation (1/4). Neuropathologic features included positivity for GFAP (4/5), synaptophysin (4/5), NSE (2/2), NeuN (4/4), and variable Ki-67 (< 1% to 15%). Next generation sequencing (3/5) and microarray (3/5) collectively were abnormal in four of five tumors. Methylation profiling was successfully performed on four of five samples which led to modification of diagnosis in two patients and the others were either unclassifiable or confirmatory with the histologic diagnosis. Mean time to follow up was 77 months (range 44-112 months). Mean progression free survival and overall survival were 24 months (range 6 to 52 months) and 100% respectively. CONCLUSION: Neurocytomas are a rare clinical entity that warrants further investigation into molecular and pathologic prognosticating features. Methylation profiling may aid in differentiation of neurocytoma from other difficult to diagnose tumors who share similar histologic features.

State-level political partisanship strongly correlates with health outcomes for US children.

The Cook Partisan Voting Index (PVI) determines how strongly a state leans toward the Democratic or Republican Party in US presidential elections compared to the nation. We set out to determine the correlation between childhood health outcomes and state-level partisanship using PVI. Sixteen measures of childhood health were obtained from several US governmental agencies for 2003-2017. The median PVI for every state was calculated for the same time period. Pearson's rho determined the correlation between PVI and each health outcome. Multiple regression was also conducted, adjusting for educational attainment and percentage of non-White residents. We also compared childhood health in moderately Democratic and Republican states (5-9.9% more Democratic/Republican than the national mean) and, similarly, for extremely Democratic and Republican states (10% or more Democratic/Republican than the national mean), using Wilcoxon tests. For all 16 health measures, the median values in Democratic-leaning states represented better outcomes than Republican-leaning states (9/16 had a beta value for linear regression associated with P < 0.05). When compared to Republican states, the median values in moderately Democratic states represented better outcomes for 14 of 16 health measures (9/14 associated with P < 0.05). Similarly, the median values for extremely Democratic states represented better outcomes with regard to all 16 health measures, when compared to Republican-leaning states (8/16 associated with P < 0.05).Conclusions: Democratic-leaning states displayed superior outcomes for multiple childhood health measures when compared to Republican counterpart states. Future research should investigate the significance of these findings and attempt to determine which state-level policies may have contributed to such disparate health outcomes. What is Known: • In the United States, many health disparities exist among children along racial, economic and geographic lines. • Many US states lean strongly towards either the Democratic or Republican political parties in federal elections. What is New: • Trends for multiple measures of childhood health vary in association with the political partisanship of the state being examined. • Multiple barometers of childhood health are superior in Democratic-leaning states, while no measures are better in Republican-leaning states.

Preliminary Evidence-Based Method of Medical Kit Design for Wilderness Expeditions Modeled by a High-Altitude Expedition to Mount Kilimanjaro.

BACKGROUND: Wilderness expeditions require extensive planning and the correct medical supplies to ensure clinical care is possible in the event of illness or injury. There are gaps in the literature regarding evidence-based methods for medical kit design. OBJECTIVES: This report describes a preliminary method for predicting medical events to determine medical supply requirements for a wilderness expedition. The performance of this method was evaluated using data from the 2017 Equal Playing Field (EPF) expedition to Mount Kilimanjaro. METHODS: Eight reports documenting medical events during wilderness expeditions were reviewed. Incidence data were consolidated into a new dataset, and a subset of data from adventure race expeditions (ARS) was created. The cumulative incidence of medical events was then predicted for the 9-day EPF expedition. The medical supply list was determined based on indication. The effectiveness of the full dataset and ARS to predict the cumulative incidence of medical events by category during the EPF expedition was evaluated using regression analysis. RESULTS: The ARS predicted a higher incidence rate of medical events than the full dataset did but underestimated the EPF expedition incidence rate. The full dataset was a weak predictor of the cumulative incidence of medical events by category during the EPF expedition, while the ARS was a strong predictor. The finalized medical kit overestimated all nonreusable supplies. CONCLUSIONS: The medical kit created using this method managed all medical events in the field. This report demonstrates the potential utility of using a tailored, evidence-based approach to design a medical kit for wilderness expeditions.

Trametinib-based Treatment of Pediatric CNS Tumors: A Single Institutional Experience.

MEK inhibitors are an emerging therapy with increasing use in mitogen-activated protein kinase-driven central nervous system (CNS) tumors. There is limited data regarding efficacy and toxicity in pediatric patients. We report our clinical experience with trametinib-based therapy for the treatment of 14 consecutive pediatric patients with recurrent low-grade glioma (N=11) or high-grade CNS tumors (N=3) with MAP kinase pathway mutations. Patients received trametinib as monotherapy (N=9) or in combination (N=5) with another antineoplastic agent. Nine patients (64%) were progression free during treatment. Five patients showed a partial response, while 4 had stable disease. Two patients (14%) progressed on therapy. All partial responses were in patients with low-grade tumors. The remaining 3 patients were not evaluable due to toxicity limiting duration of therapy. Two of 3 patients with low-grade glioma with leptomeningeal dissemination showed radiographic treatment response. Five patients reported improved clinical symptoms while on trametinib. Adverse events on trametinib-based therapy included dermatologic, mouth sores, fever, gastrointestinal, infection, neutropenia, headache, and fatigue, and were more common in patients using combination therapy. Trametinib-based therapy demonstrated signals of efficacy in our single institutional cohort of pediatric patients with mitogen-activated protein kinase-driven CNS tumors. Our observations need to be confirmed in a clinical trial setting.

Deep Vein Thrombosis in a Young, Healthy Baseball Catcher: A Case Report and Review of the Literature.

Venous thromboembolism is becoming increasingly recognized as a significant cause of morbidity and mortality in the hospitalized pediatric population. However, young healthy athletes can present with unique risk factors for deep vein thrombosis (DVT) that can be overlooked. Here we report a case of an adolescent male with no inherited risk factors or prior history of DVTs who developed a right femoral vein DVT in the context of playing catcher in baseball after recovering from a bout of streptococcal pharyngitis. We review the evidence that suggests that repetitive squatting-induced compression of the femoral vein can cause the venous stasis and endothelial microtrauma that contributed to the formation of this thrombus.

Treatment of Recurrent Refractory Pediatric Pre-B Acute Lymphoblastic Leukemia Using Inotuzumab Ozogamicin Monotherapy Resulting in CD22 Antigen Expression Loss as a Mechanism of Therapy Resistance.

BACKGROUND: Inotuzumab ozogamicin is a novel antibody-drug conjugate that targets CD22, a common antigen on pre-B acute lymphoblastic leukemia cells. OBSERVATIONS: A 7-year-old boy with pre-B acute lymphoblastic leukemia in his second relapse was given 2 cycles of inotuzumab ozogamicin. He responded morphologically with a negative bone marrow evaluation. However, he relapsed in cycle 3 of therapy with a loss of CD22 expression on his lymphoblast population. CONCLUSION: To our knowledge, this is the first published case of CD22 expression loss as a mechanism of therapy resistance for inotuzumab ozogamicin.

Hematologic Manifestations of Nutritional Deficiencies: Early Recognition is Essential to Prevent Serious Complications.

Nutritional deficiencies, including deficiencies of vitamin B12, copper, and vitamin C, may result in cytopenias and hematologic symptoms. Early recognition of these deficiencies is imperative for prompt treatment and improvement in hematologic and other manifestations. We describe 5 cases which illustrate the hematologic manifestations of nutritional deficiencies and challenges to initial diagnosis and management. Supplementation of the deficient vitamin or micronutrient in all of these cases resulted in rapid resolution of cytopenias, hemorrhage, and other associated hematologic symptoms. We also review other nutritional deficiencies that manifest with hematologic symptoms and compile recommendations on treatment and expected time to response.

Treatment rate of strabismus and amblyopia is associated with the location of pediatric ophthalmologists in the United States.

PURPOSE: To determine whether the geographic density of pediatric ophthalmologists is associated with the rate of children treated for strabismus and amblyopia. METHODS: This cross-sectional study included children treated for strabismus and amblyopia 0-17 years of age with commercial insurance who were included in the Vision and Eye Health Surveillance System. Additionally, pediatric ophthalmologists by state were determined using the American Association for Pediatric Ophthalmology and Strabismus website. Unadjusted linear regression was used to compare the geographic density of pediatric ophthalmologists and the rate of children treated for strabismus and amblyopia by state in 2016. This was repeated using multivariable linear regression, controlling for race, poverty, non-English-speaking children, and insurance coverage for children by state. RESULTS: New York and Mississippi had the highest and lowest rates of treatment of strabismus and amblyopia, with 3.97 and 0.83 children treated per 100 children, respectively. The geographic density of pediatric ophthalmologists was associated with the rate of children treated for strabismus and amblyopia in unadjusted analyses (ß = 0.62, P < 0.001). Further, the geographic density of pediatric ophthalmologists was associated with the rate of children treated for strabismus and amblyopia in adjusted analyses (ß = 0.61, P < 0.001). CONCLUSIONS: The geographic density of pediatric ophthalmologists by state was positively associated with the rate of children treated for strabismus and amblyopia.

Modeling the Relationship Between Firearm Restrictions, Medicaid Expansion, and Political Partisanship with Pediatric Firearm Mortality Costs.

INTRODUCTION: Firearms are now the leading cause of pediatric mortality in the U.S., but few studies have investigated the economic impact of these deaths. Thus, this study determined whether multiple different gun-related measures, political partisanship and Medicaid expansion were related to the costs of pediatric gun deaths. METHODS: Each states' medical costs, years of potential life lost (YPLL), and value of statistical life (VSL) lost due to pediatric gun deaths were extracted from the WISQARS database from 2015 to 2020. Seven firearm laws or restrictiveness measures (assault weapons bans, child access prevention laws, firearm registration and permit to purchase requirements, safe storage laws, Giffords Law Center ranking, and the number of firearm provisions), the Cook Partisan Voting Index (PVI), and Medicaid expansion status were determined across states. Unadjusted analyses compared each measure and (1) medical costs, (2) VSL, and (3) YPLL for each state. These were repeated using adjusted analyses, controlling for poverty, educational attainment, poor mental health, and race. RESULTS: Of the 9 variables assessed, unadjusted analyses revealed that 8 variables were significantly associated with increased medical costs, all 9 were associated with higher VSL and 8 were associated with higher YPLL due to pediatric firearm-related mortality. Multivariable analyses revealed that 7 variables were associated with medical costs, 7 were associated with VSL and 6 were associated with YPLL. CONCLUSION: States with fewer gun laws and those which have not adopted Medicaid expansion were more likely to experience a higher economic burden due to pediatric gun deaths. Quantifying the costs of these deaths can demonstrate the social toll of gun violence to policymakers and the general public. LEVEL OF EVIDENCE: III.

Does KUB play a role in the diagnosis of bladder bowel dysfunction?

INTRODUCTION: Kidney ureter bladder radiography (KUB) is widely used for the evaluation of constipation in children with bladder and bowel dysfunction (BBD); however, there is varying evidence to support its routine diagnostic use. One drawback to KUB is radiation exposure. The dangers of radiation in children are well-documented, and per As Low As Reasonably Achievable, non-beneficial radiation should be avoided. This risk is especially high in children who undergo repeated imaging in the follow up of constipation treatment. OBJECTIVE: We sought to assess the utility of KUB in diagnosing children with BBD by comparing it to four diagnostic tests and/or validated instruments: the Dysfunctional Voiding Symptom Score (DVSS), Rome IV criteria, rectal diameter on ultrasound (RD), and the Bristol Stool Form Score (BSFS). STUDY DESIGN: We prospectively enrolled a cohort of patients presenting to an academic pediatric urology practice with symptoms of BBD. Severity of stool burden on KUB (mild, moderate, or severe), RD on ultrasound (≥3.4 cm), DVSS, Rome IV, and BSFS were obtained for each patient. All imaging was interpreted by a pediatric radiologist and pediatric urologist. Primary outcomes were the association between the four diagnostic tests and KUB stool burden. Bivariate analysis of all individual variables versus KUB was performed, as well as multivariate regressions to determine if multiple measures were predictive of KUB stool burden when combined. RESULTS: Between October 2020 and May 2022, 50 patients were enrolled. All children were under the age of 18, with a median age of 8 years (IQR 3-13). 38 % were male. Median BMI-for-age-percentile was 80.8 (IQR 50.3-98.3). When comparing individual variables to KUB in bivariate analyses, it was found that RD on ultrasound is predictive of significant stool burden on KUB (p = 0.03). No other individual variables were predictive. In the multivariate analyses, no combination of tests was found to be predictive of KUB. DISCUSSION: We compared the effectiveness of four commonly used diagnostic tests in children with BBD to validate the use of KUB. In conclusion, our results support the use of RD on ultrasound as a non-radiating alternative to KUB to assess stool burden. Data also suggest that KUB for fecal load does not correlate with urinary (DVSS) or bowel (Rome IV, BSFS) symptoms in BBD, and that symptoms scores should still be used independently for diagnosis and monitoring of treatment response. CONCLUSION: In conclusion, KUB has a limited role in the diagnosis of BBD.

Associations between Statin Use and Glaucoma in the All of Us Research Program.

PURPOSE: To investigate associations between statin use and glaucoma in the 2017-2022 All of Us (AoU) Research Program. DESIGN: Cross-sectional, population-based. PARTICIPANTS: 79,742 adult participants aged ≥ 40 years with hyperlipidemia and with electronic health record (EHR) data in the AoU database. METHODS: Hyperlipidemia, glaucoma status, and statin use were defined by diagnoses and medication information in EHR data collected by AoU. Logistic regression analysis was performed to evaluate the association between statin use and glaucoma likelihood. Logistic regression modeling was used to examine associations between glaucoma and all covariates included in adjusted analysis. Serum low-density lipoprotein cholesterol (LDL-C) was used to assess hyperlipidemia severity. Analyses stratified by LDL-C level and age were performed. MAIN OUTCOME MEASURES: Any glaucoma as defined by International Classification of Diseases (ICD) codes found in EHR data. RESULTS: Of 79,742 individuals with hyperlipidemia in AoU, there were 6,365 (8.0%) statin users. Statin use was associated with increased glaucoma prevalence when compared with statin non-use (adjusted odds ratio [aOR]: 1.13, 95% confidence interval [CI]: 1.01-1.26). Higher serum levels of LDL-C were associated with increased odds of glaucoma (aOR: 1.003, 95% CI: 1.003, 1.004). Statin users had significantly higher LDL-C levels compared to nonusers (144.9 mg/dL versus 136.3 mg/dL, p-value < 0.001). Analysis stratified by LDL-C identified positive associations between statin use and prevalence of glaucoma among those with optimal (aOR = 1.39, 95% CI = 1.05-1.82) and high (aOR = 1.37, 95% CI = 1.09-1.70) LDL-C levels. Age-stratified analysis showed a positive association between statin use and prevalence of glaucoma in individuals aged 60-69 years (aOR = 1.28, 95% CI = 1.05-1.56). CONCLUSIONS: Statin use was associated with increased glaucoma likelihood in the overall adult AoU population with hyperlipidemia, in individuals with optimal or high LDL-C levels, and in individuals 60-69 years old. Findings suggest that statin use may be an independent risk factor for glaucoma, which may furthermore be affected by one's lipid profile and age.

State Gun Regulations and Reduced Gun Ownership are Associated with Fewer Firearm-Related Suicides Among Both Juveniles and Adults in the USA.

BACKGROUND: Few studies have investigated the relationship between specific gun regulations and gun ownership with the firearm-related suicide rate among juveniles and adults across U.S. states. Therefore, this study seeks to determine if gun ownership rates and gun restrictions are related to the firearm-related suicide rate in both the pediatric and adult populations. METHODS: Fourteen measures of state gun law restrictions and gun ownership were collected. These included Giffords Center ranking, gun ownership percentages, and 12 specific firearm laws. Unadjusted linear regressions modeled the relationship between each individual variable and the rate of firearm-related suicides for adults and children across states. This was repeated using a multivariable linear regression adjusting for poverty, poor mental health, race, gun ownership, and divorce rates by state. P values of <0.004 were considered significant. RESULTS: In the unadjusted linear regression, 9 of 14 firearm-related measures were statistically associated with fewer firearm-related suicides in adults. Similarly, 9 of 14 measures were found to be associated with fewer firearm-related suicides in the pediatric population. In the multivariable regression, 6 of 14 vs. 5 of 14 measures were statistically associated with fewer firearm-related suicides in the adult and pediatric populations, respectively. CONCLUSIONS: Ultimately, this study found that increased state gun restrictions and lower gun ownership rates were associated with fewer firearm related suicides among juveniles and adults in the US. This paper provides objective data to help lawmakers as they create gun control legislation that can potentially decrease the rate of fire-arm related suicide. LEVELS OF EVIDENCE: II.

An Assessment of the Relationship Between BMI and Children Undergoing Surgical Procedures: A Retrospective Study.

Background: While multiple studies have documented that obesity increases the risk of operative complications among adults, little data exist on how obesity impacts surgical outcomes among children. We aimed to determine if children with obesity have different postoperative outcomes than their peers. Methods: A retrospective chart review was conducted of 875 patients aged between 2 and 18 years who underwent surgery during 2018. Patients were stratified, based on BMI percentile for age, as having less than healthy weight (<5th percentile), healthy weight (5th-84th percentile), excess weight (85th-94th percentile), or obesity (≥95th percentile). Demographic information and data on medical comorbidities and postoperative complications were collected. All analyses were conducted using chi-square or Kruskal-Wallis testing. Results: Eighty-two patients were excluded due to lack of BMI data and 56 were excluded as they had below healthy weight. Of the remaining 737 patients, 475 (64.4%) had healthy weight, 124 (16.8%) had excess weight, and 138 (18.70%) had obesity. Children with obesity had more tonsillectomy/adenoidectomy (p < 0.01) and vascular access (p = 0.04) procedures compared with peers. Additionally, patients with obesity were more likely to have a pre-existing history of liver disease (p < 0.01) and more frequently developed postoperative wound dehiscence (p < 0.01). No other complications occurred more frequently among children with obesity. Conclusions: Children with obesity required more tonsillectomy/adenoidectomy and vascular access procedures. Wound dehiscence was the only complication that was associated with obesity. This suggests that children with obesity are not inherently more prone to experience surgical complications and therefore elective procedures should likely not be deferred until preoperative weight loss is achieved.

Does Fever Response to Acetaminophen Predict Bloodstream Infections in Febrile Neutropenia?

BACKGROUND: There is a need to identify clinical parameters for early and effective risk stratification and prediction of bacterial bloodstream infections (BSIs) in patients with febrile neutropenia (FN). Acetaminophen is used widely to treat fever in FN; however, little research exists on whether fever response to acetaminophen can be used as a predictor of BSIs. OBJECTIVES: Investigate the relationship between fever response to acetaminophen and bacteremia in FN. DESIGN/METHOD: A retrospective review of patients (1-21 years old) presenting with FN and bacteremia at Rady Children's Hospital (2012-2018) was performed. Demographic information, presenting signs/symptoms, degree of neutropenia (absolute neutrophil count (ANC) > 500 or < 500 cells/µL), absolute monocyte count, blood culture results, temperatures one, two, and six hours after acetaminophen, and timing of antibiotic administration were examined. Patients were stratified into three malignancy categories: leukemia/lymphoma, solid tumor, and hematopoietic stem cell transplant. Patients were matched with culture-negative controls based on sex, age, malignancy category, and degree of neutropenia. RESULTS: Thirty-five case-control pairs met inclusion criteria (70 presentations of FN). The mean age of the cases was 10.7 years (± 6.3) vs. 10.0 years (± 5.9) for the controls. Twenty were female (57%). Twenty-three pairs were categorized as leukemia/lymphoma (66%), eight as solid tumors (23%), and four as HSCT (11%). Thirty-four pairs (97%) had a presenting ANC < 500 cells/µL. Higher temperature one-hour post-acetaminophen was associated with bacteremia (p = 0.04). Logistic regression demonstrated that temperature one-hour post-acetaminophen had a significant predictive value for bacteremia (p = 0.011). The area under the receiver operating characteristic curves for logistic regression and classification and regression tree analysis were 0.70 and 0.71, respectively. CONCLUSION: While temperature one-hour post-acetaminophen was higher among patients with bacteremia and was a significant predictor of bacteremia, fever response in isolation lacks sufficient predictive value to impact clinical decision-making. Future studies are needed to assess fever responsiveness as an adjunct to existing modalities of FN risk stratification.