Assessment of blood-brain barrier penetration of miltefosine used to treat a fatal case of granulomatous amebic encephalitis possibly caused by an unusual Balamuthia mandrillaris strain.

Balamuthia mandrillaris, a free-living ameba, causes rare but frequently fatal granulomatous amebic encephalitis (GAE). Few patients have survived after receiving experimental drug combinations, with or without brain lesion excisions. Some GAE survivors have been treated with a multi-drug regimen including miltefosine, an investigational anti-leishmanial agent with in vitro amebacidal activity. Miltefosine dosing for GAE has been based on leishmaniasis dosing because no data exist in humans concerning its pharmacologic distribution in the central nervous system. We describe results of limited cerebrospinal fluid (CSF) and serum drug level testing performed during clinical management of a child with fatal GAE who was treated with a multiple drug regimen including miltefosine. Brain biopsy specimens, CSF, and sera were tested for B. mandrillaris using multiple techniques, including culture, real-time polymerase chain reaction, immunohistochemical techniques, and serology. CSF and serum miltefosine levels were determined using a liquid chromatography method coupled to tandem mass spectrometry. The CSF miltefosine concentration on hospital admission day 12 was 0.4 µg/mL. The serum miltefosine concentration on day 37, about 80 h post-miltefosine treatment, was 15.3 µg/mL. These are the first results confirming some blood-brain barrier penetration by miltefosine in a human, although with low-level CSF accumulation. Further evaluation of brain parenchyma penetration is required to determine optimal miltefosine dosing for Balamuthia GAE, balanced with the drug's toxicity profile. Additionally, the Balamuthia isolate was evaluated by real-time polymerase chain reaction (PCR), demonstrating genetic variability in 18S ribosomal RNA (18S rRNA) sequences and possibly signaling the first identification of multiple Balamuthia strains with varying pathogenicities.

Creation of an empiric tool to predict ECMO deployment in pediatric respiratory or cardiac failure.

PURPOSE: To create a real-time prediction tool to predict probability of ECMO deployment in children with cardiac or pulmonary failure. MATERIALS AND METHODS: Patients ≤18 years old admitted to an ICU that participated in the Virtual Pediatric Systems database (2009-2015) were included. Logistic regression models using adaptive lasso methodology were used to identify independent factors associated with ECMO use. RESULTS: A total of 538,202 ICU patients from 140 ICUs qualified for inclusion. ECMO was deployed in 3484 patients (0.6%) with a mortality of 1450 patients (41.6%). The factors associated with increased probability of ECMO use included: younger age, pulmonary hypertension, congenital heart disease, high-complexity cardiac surgery, cardiomyopathy, acute lung injury, shock, renal failure, cardiac arrest, use of nitric oxide, use of either conventional mechanical ventilation or high frequency oscillatory ventilation, and higher annual ECMO center volume. The area under the receiver operating curve for this model was 0.90 (95% CI: 0.85-0.93). This tool can be accessed at https://soipredictiontool.shinyapps.io/ECMORisk/. CONCLUSIONS: Here, we present a tool to predict ECMO deployment among critically ill children; this tool will help create real-time risk stratification among critically ill children, and it will help with benchmarking, family counseling, and research.

Cytochrome P450 mediated-drug metabolism is reduced in children with sepsis-induced multiple organ failure.

OBJECTIVE: Antipyrine metabolism is a "gold standard" measure of mixed cytochrome P450 (CYP) mediated drug metabolism in humans. Cytokines (e.g., interleukin-6) and nitric oxide reduce CYP 450 activity in vitro and in vivo. Because interleukin-6 and nitric oxide production increases in children with sepsis-induced multiple organ failure, we hypothesized impaired CYP 450 mediated drug metabolism in this population. METHODS: Fifty-one consecutive children with sepsis and six critically ill children without sepsis were enrolled and given 18 mg/kg antipyrine per NG. Plasma antipyrine elimination rate, elimination half-life, and apparent oral clearance were measured and calculated. Plasma interleukin-6 and nitrite plus nitrate levels were measured and organs failing scored on days 1-3 of sepsis. RESULTS: Children with sepsis had a twofold reduction in antipyrine clearance. Children with persistent failure of three or more organs had a fourfold reduction in antipyrine clearance. Antipyrine clearance was inversely correlated to circulating interleukin-6 and nitrite plus nitrate levels and to number of organ failures. CONCLUSIONS: Interpretation CYP 450 mediated drug metabolism is decreased in children with sepsis, related in part to the degree of inflammation and organ failure. For drugs metabolized by CYP 450 enzymes there is an urgent need to reevaluate the use of standard drug dosage schedules in the sepsis population

Procalcitonin is persistently increased among children with poor outcome from bacterial sepsis.

OBJECTIVE: To examine the relationships between procalcitonin, bacterial infection, sepsis-induced multiple organ failure, and mortality rate in children. DESIGN: Cohort study. SETTING: A multidisciplinary, tertiary-care pediatric intensive care unit. PATIENTS: Seventy-eight children meeting criteria for sepsis or septic shock and 12 critically ill children without sepsis. INTERVENTIONS: Venous or arterial blood sampling. MEASUREMENTS AND MAIN RESULTS: Demographic, epidemiologic, and outcome data were recorded. Plasma from children with sepsis were collected on days 1 and 3, and procalcitonin concentrations were measured by immunoluminometric assay. Organ failure index scores were determined, and multiple organ failure was defined as organ failure index > or = 3. Persistent multiple organ failure was defined by presence of multiple organ failure on day 3. Procalcitonin concentrations (median [25th percentile-75th percentile]) were increased among children with sepsis on day 1 (2.4 ng/mL [0.2-24.2], p < .01) but not on day 3 (0.8 ng/mL [0.1-8.1], p = nonsignificant) vs. controls (0.2 ng/mL [0.1-0.5]). This increase in procalcitonin concentration was particularly robust among children with bacterial sepsis on day 1 (7.1 ng/mL [0.9-44.8], p < .001) and on day 3 (2.9 ng/mL [0.1-32.4], p < .05). Procalcitonin concentrations were not increased among children with fungal, viral, or culture-negative sepsis vs. controls. Procalcitonin concentrations were persistently increased over time among patients with bacterial sepsis who had persistent multiple organ failure (p < .05) and who died (p < .01) but not among patients with nonbacterial sepsis. CONCLUSIONS: Procalcitonin is persistently increased among children with poor outcome from bacterial sepsis. Further study is needed to better delineate this differential procalcitonin response to bacterial vs. nonbacterial sepsis and to characterize any mechanistic role that procalcitonin might play in the development of bacterial sepsis-induced multiple organ failure and mortality.