Methicillin-Sensitive Staphylococcus aureus Co-infection in Adolescent Patients With Delta-Variant SARS-CoV-2 Acute Respiratory Failure.

We report a series of five pediatric patients admitted with acute respiratory failure due to delta-variant SARS-CoV-2, found to have a methicillin-sensitive Staphylococcus aureus (MSSA) co-infection. All five patients required escalation of their respiratory support within 24 hours of discovering the MSSA infections. Four out of the five patients received immune-modulating therapies. Four patients required extracorporeal membrane oxygenation support. One patient died, and the other four survived until hospital discharge. Clinicians should consider secondary bacterial infections in patients with COVID-19 treated with immune modulators. MSSA co-infection can lead to increased morbidity and mortality in patients with COVID-19.

Association Between Elevated RBC Distribution Width and Multiple Organ Dysfunction in Pediatric Critical Illness.

OBJECTIVES: RBC distribution width, a part of the complete blood count, has been shown in several published studies to be a strong biomarker of adverse outcomes. We sought to determine the association between admission RBC distribution width value and clinical outcomes including multiple organ dysfunction, mechanical ventilation days, PICU length of stay, and hospital length of stay in children admitted to the PICU. DESIGN: Single center, retrospective study. SETTING: A tertiary pediatric hospital in the United States. PATIENTS: All subjects admitted to the PICU from 2016 to 2017. EXCLUSIONS: Greater than 21 years old, pregnancy, and history of packed RBC transfusion within 120 days prior to admission. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One-thousand five-hundred one subjects were screened and 856 were included in data analysis. RBC distribution width value was categorized into four separate groups: group I (RBC distribution width < 13.4%), group II (13.4-14.3%), group III (14.4-15.7%), and group IV (RBC distribution width > 15.7%). Increased RBC distribution width at admission was associated with multiple organ dysfunction syndrome in the first 7 days (group I = 11.8% vs group IV = 30.1%; p < 0.0001) (odds ratio, 3.22; 95% CI, 1.95-5.30; p < 0.0001). Increased RBC distribution width was associated with increased median mechanical ventilation duration (group IV = 7 d vs group I = 5 d; p = 0.001), median hospital length of stay (group IV = 13 d vs group I = 5 d; p < 0.0001), and median PICU length of stay (group IV = 4 d vs group I = 3 d; p = 0.01). Mortality was not statistically associated with admission RBC distribution width (p = 0.12). CONCLUSIONS: PICU admission RBC distribution width values greater than 15.7% obtained upon admission to the PICU in patients who have not received a RBC transfusion are associated with multiple organ dysfunction syndrome in the first 7 days of admission, increased duration of mechanical ventilation, and increased hospital length of stay.

Platelet Glycoprotein VI Haplotypes and the Presentation of Paediatric Sepsis.

Sepsis triggers a complex series of pathophysiologic events involving inflammatory responses and coagulation abnormalities. While circulating blood platelets are well-characterized for their contributions to coagulation, increasingly platelet-dependent effects on inflammation are being recognized. Here, we focus on the platelet membrane receptor, glycoprotein VI (GPVI), and its role in platelet microparticle (pMP) release. The GPVI receptor is a platelet-specific collagen membrane receptor that, upon ligand binding, facilitates the release of pMPs. As membrane-bound platelet fragments of less than 1 µm, pMPs are known to have both pro-inflammatory and pro-coagulant properties. Thus, pMPs are potentially impacting sepsis at multiple stages of the inflammatory response. Studies are presented documenting the impact of the most common GPVI haplotypes, GPVIa and GPVIb, on pMP levels and release in healthy individuals (n = 49). The GPVIa haplotype corresponds to an approximately twofold increase in circulating pMPs as a percentage of total microparticles in healthy individuals along with a heightened in vitro release of pMPs. Additionally, patients admitted to a paediatric intensive care unit (ICU) (n = 73) with an initial diagnosis of sepsis were recruited and their GPVI haplotypes determined. Septic patients of the GPVIa haplotype (n = 59) were statistically more likely to present with a diagnosis of severe sepsis or septic shock, as compared with GPVIb individuals (n = 14). Independent disease classification via PELOD-2 and Pediatric Risk of Mortality III scores confirmed individuals with the GPVIa haplotype were more likely to have significant organ failure. Thus, GPVI haplotypes influence pMP levels in the circulation and are predictive of sepsis severity when presenting to the ICU.

von Willebrand factor multimers in pediatric extracorporeal membrane oxygenation support.

Acquired von Willebrand factor (vWF) disease is associated with a decrease in the amount of circulating high molecular weight (HMW) vWF multimers. vWF has not been previously investigated in children on extracorporeal membrane oxygenation (ECMO) support. We hypothesized that HMW vWF multimers and vWF activity decrease over the course of ECMO support in these patients. This prospective, single center, observational, cohort pilot study was carried out between December 2010 and April 2011 and included patients 0 to 18 years old requiring ECMO support at our institution. Blood samples were tested for various aspects of vWF. Mean and standard deviation were estimated for vWF activity and multimers, whereas a generalized linear model was developed to estimate multimer changes over time.The study included six pediatric patients. The mean age of the patients was 54.9 ± 55.3 (mean ± standard deviation) months. The mean HMW vWF multimer percentage was 23.4 ± 7.3 in the pre-ECMO samples and significantly decreased over time (p<0.003). There was no significant change in low molecular weight vWF multimer percentage. An immediate decrease in vWF HMW multimers as a percentage of all multimers once ECMO is initiated was noted and persisted across the study period.

High-dose argatroban for heparin-induced thrombocytopenia in a child using a ventricular assist device.

A 10-year-old boy who was receiving support from a ventricular assist device (VAD) experienced heparin-induced thrombocytopenia that was successfully treated with high-dose argatroban infusion to attain therapeutic activated partial thromboplastin time in spite of high serum argatroban levels. This case also highlights bolus argatroban dosing for VAD change in the setting of persistent ventricular fibrillation.