Candida endocarditis: contemporary cases from the International Collaboration of Infectious Endocarditis Merged Database (ICE-mD)

Candida infective endocarditis (IE) is increasingly common, yet most reports have been single-center reviews. We evaluated 16 patients with Candida IE nested within a cohort of 2,022 patients with IE. Prosthetic valve IE was more common in patients with Candida (50% vs 17%); mortality was 37% for patients with Candida.

Racial differences are seen in blood pressure response to fosinopril in hypertensive children

BACKGROUND

Few antihypertensive therapies have been systematically studied in children and dosages for many agents are either extrapolated from adult studies or obtained from small homogenous pediatric populations. It is well established that adult patients of different races show disparate response to angiotensin-converting enzyme (ACE) inhibitors, however no such studies have been performed in children.

METHODS

Two hundred fifty three children ages 6-16 with hypertension or with high normal blood pressure with an associated medical condition requiring antihypertensive therapy were enrolled at 78 clinical sites in the US, Russia, and Israel in a double blind study to evaluate the efficacy of fosinopril compared to placebo.

RESULTS

The racial composition of the cohort included 60.1% white (152/253), 20.6% black (52/253), 13.8% Hispanic (35/253), 2.0% Asian (5/253), 0.4% Native American (1/253), and 3.2% (8/253) children classified as other or of mixed race. After adjusting for baseline blood pressure and body surface area (BSA) there was no significant dose response seen in non-black patients. Non-blacks randomized to the low, medium, and high dosages of fosinopril all had a mean decrease of 12 mm Hg in their sequential systolic BP (SBP). Blacks, however, demonstrated a significant dose response to fosinopril; those who received the low dosage had a 5 mm Hg decrease in SBP, and those who received the high dosage had a mean 13 mm Hg decrease in SBP.

CONCLUSIONS

Fosinopril was effective in treating hypertension, but black children required a higher dose per body weight in order to achieve adequate control. This suggests that black children treated with fosinopril for hypertension on average require higher doses to achieve adequate systolic blood pressure control that non-black children.

Population pharmacokinetics of intravenous acyclovir in preterm and term infants

BACKGROUND

Acyclovir is used to treat herpes infections in preterm and term infants; however, the influence of maturation on drug disposition and dosing requirements is poorly characterized in this population.

METHODS

We administered intravenous acyclovir to preterm and term infants <31 days postnatal age and collected plasma samples. We performed a population pharmacokinetic analysis. The primary pharmacodynamic target was acyclovir concentration ≥3 mg/L for ≥50% of the dosing interval. The final model was simulated using infant data from a clinical database.

RESULTS

The analysis included 28 infants (median 30 weeks gestation). Acyclovir pharmacokinetics was described by a 1-compartment model: clearance (L/h/kg) = 0.305 × [postmenstrual age (PMA)/31.3 weeks]. This equation predicts a 4.5-fold increase in clearance from 25 to 41 weeks PMA. With proposed dosing, the pharmacodynamic target was achieved in 91% of infants: 20 mg/kg every 12 hours in infants <30 weeks PMA; 20 mg/kg every 8 hours in infants 30 to <36 weeks PMA and 20 mg/kg every 6 hours in infants 36-41 weeks PMA.

CONCLUSIONS

Acyclovir clearance increased with infant maturation. A dosing strategy based on PMA accounted for developmental changes in acyclovir disposition to achieve the surrogate pharmacodynamic target in many infants.

Thirty-day postoperative death rate at an academic medical center

OBJECTIVE

To improve understanding of perioperative deaths at an academic medical center.

SUMMARY BACKGROUND DATA

Because published data have typically focused on specific patient populations, diagnoses, or procedures, there are few data regarding surgical deaths and complications in institutional or regional studies. Specifically, surgical adverse events and errors are generally not studied comprehensively. This limits the overall understanding of complications and deaths.

METHODS

Data from all operations performed in the main operating suite of the University of Virginia Health Sciences Center from January 1 to June 30, 1999, were compared with state death records to gain a dataset of patients dying within 30 days of surgery. All clinical records from patients who died were screened for adverse events and subsequently reviewed by three surgeons who identified adverse events and errors and performed comparisons with survivors.

RESULTS

One hundred nineteen deaths followed 7,379 operations performed on 6,296 patients, yielding a patient death rate of 1.9%. Patients dying within 30 days of surgery were older and had higher American Society of Anesthesiologists scores. Of 119 deaths, 86 (72.3%) were attributable to the patient's primary disease. Twenty-three patient deaths (19.3% of all deaths, 0.37% of all patients) could not be attributed to the patient's primary disease and thus were suspicious for an adverse event (AE) as the cause of the death. Of the 23 deaths suspicious for AE, 15 (12.6% of all deaths, and 65.2% of AE deaths) followed an error in care and thus were classified as potentially preventable, affecting 0.24% of the study population.

CONCLUSIONS

Overall, the 30-day postoperative death rate was low in the total surgical population at an academic medical center. Errors and AEs were associated with 12.6% and 19.3% of deaths, respectively. Retrospective review inadequately characterized the nature of AEs and failed to determine causality. Prospective audits of outcomes will enhance our understanding of surgical AEs.

Caspofungin for the treatment of azole resistant candidemia in a premature infant

Candidemia is common in extremely low birth weight infants and is associated with substantial mortality and morbidity. Treatment options have traditionally been limited to amphotericin B deoxycholate or fluconazole. We present a case of a premature infant with persistent candidemia despite antifungal treatment that responded to therapy with caspofungin, an echinocandin antifungal. The infant's Candida isolate developed resistance to azoles during fluconazole administration and also suffered from severe hypercalcemia during the initiation of caspofungin therapy.

Simulated Assessment of Pharmacokinetically Guided Dosing for Investigational Treatments of Pediatric Patients With Coronavirus Disease 2019

IMPORTANCE

Children of all ages appear susceptible to severe acute respiratory syndrome coronavirus 2 infection. To support pediatric clinical studies for investigational treatments of coronavirus disease 2019 (COVID-19), pediatric-specific dosing is required.

OBJECTIVE

To define pediatric-specific dosing regimens for hydroxychloroquine and remdesivir for COVID-19 treatment.

DESIGN, SETTING, AND PARTICIPANTS

Pharmacokinetic modeling and simulation were used to extrapolate investigated adult dosages toward children (March 2020-April 2020). Physiologically based pharmacokinetic modeling was used to inform pediatric dosing for hydroxychloroquine. For remdesivir, pediatric dosages were derived using allometric-scaling with age-dependent exponents. Dosing simulations were conducted using simulated pediatric and adult participants based on the demographics of a white US population.

INTERVENTIONS

Simulated drug exposures following a 5-day course of hydroxychloroquine (400 mg every 12 hours × 2 doses followed by 200 mg every 12 hours × 8 doses) and a single 200-mg intravenous dose of remdesivir were computed for simulated adult participants. A simulation-based dose-ranging study was conducted in simulated children exploring different absolute and weight-normalized dosing strategies.

MAIN OUTCOMES AND MEASURES

The primary outcome for hydroxychloroquine was average unbound plasma concentrations for 5 treatment days. Additionally, unbound interstitial lung concentrations were simulated. For remdesivir, the primary outcome was plasma exposure (area under the curve, 0 to infinity) following single-dose administration.

RESULTS

For hydroxychloroquine, the physiologically based pharmacokinetic model analysis included 500 and 600 simulated white adult and pediatric participants, respectively, and supported weight-normalized dosing for children weighing less than 50 kg. Geometric mean-simulated average unbound plasma concentration values among children within different developmental age groups (32-35 ng/mL) were congruent to adults (32 ng/mL). Simulated unbound hydroxychloroquine concentrations in lung interstitial fluid mirrored those in unbound plasma and were notably lower than in vitro concentrations needed to mediate antiviral activity. For remdesivir, the analysis included 1000 and 6000 simulated adult and pediatric participants, respectively. The proposed pediatric dosing strategy supported weight-normalized dosing for participants weighing less than 60 kg. Geometric mean-simulated plasma area under the time curve 0 to infinity values among children within different developmental age-groups (4315-5027 ng × h/mL) were similar to adults (4398 ng × h/mL).

CONCLUSIONS AND RELEVANCE

This analysis provides pediatric-specific dosing suggestions for hydroxychloroquine and remdesivir and raises concerns regarding hydroxychloroquine use for COVID-19 treatment because concentrations were less than those needed to mediate an antiviral effect.

Pharmacokinetics of Clindamycin in Obese and Nonobese Children

Although obesity is prevalent among children in the United States, pharmacokinetic (PK) data for obese children are limited. Clindamycin is a commonly used antibiotic that may require dose adjustment in obese children due to its lipophilic properties. We performed a clindamycin population PK analysis using data from three separate trials. A total of 420 samples from 220 children, 76 of whom had a body mass index greater than or equal to the 95th percentile for age, were included in the analysis. Compared to other metrics, total body weight (TBW) was the most robust measure of body size. The final model included TBW and a sigmoidal maturation relationship between postmenstrual age (PMA) and clearance (CL): CL (liters/hour) = 13.8 × (TBW/70)0.75 × [PMA2.83/(39.52.83+PMA2.83)]; volume of distribution (V) was associated with TBW, albumin (ALB), and alpha-1 acid glycoprotein (AAG): V (liters) = 63.6 × (TBW/70) × (ALB/3.3)-0.83 × (AAG/2.4)-0.25 After accounting for differences in TBW, obesity status did not explain additional interindividual variability in model parameters. Our findings support TBW-based dosing for obese and nonobese children.

Neonatal candidiasis

In neonates born weighing less than 750 g, invasive candidates is common and often fatal. This situation provides an opportunity to study antifungal prophylaxis and treatment in this patient population, in which the pharmacokinetics, safety, and efficacy of antifungal products are unknown. The disease is less prevalent in larger, more mature, infants. Although some pharmacokinetic data for some products are available for term and near-term infants, optimal product choice, closing, and other treatment strategies also are unknown in this older age group.

Group B streptococcal meningitis: cerebrospinal fluid parameters in the era of intrapartum antibiotic prophylaxis

OBJECTIVE

Describe cerebrospinal fluid parameters in infants with culture-proven Group B streptococcal meningitis in the era of intrapartum antibiotic prophylaxis.

STUDY DESIGN

Cohort study of the first lumbar puncture from 13,495 infants cared for at 150 neonatal intensive care units. We compared cerebrospinal fluid parameters [white blood cell count, red blood cell count, glucose, and protein], demographics, and outcomes between infants with and without Group B streptococcal meningitis.

RESULTS

We identified 46 infants with Group B streptococcal meningitis. The median cerebrospinal fluid white blood cell count was 271 cells/mm(3) for infants with Group B streptococcal meningitis and 6 cells/mm(3) for infants without meningitis (p=0.0001). Of the infants with Group B streptococcal meningitis, 9/46 (20%) had negative blood cultures. Meningitis complicated 22/145 (15%) of episodes of early-onset Group B streptococcal sepsis and 13/23 (57%) of episodes of late-onset Group B streptococcal sepsis.

CONCLUSIONS

Group B streptococcal meningitis occurs in the presence of negative blood cultures. In hospitalized infants who undergo a lumbar puncture, Group B streptococcal sepsis is frequently complicated by GBS meningitis.

Neonatal candidiasis: diagnosis, prevention, and treatment

Infection with Candida species is associated with significant morbidity and mortality in infants. The incidence of Candida infection varies widely across centers, likely due to differences in practice related to modifiable risk factors such as exposure to empiric antibiotics and length of parenteral nutrition. Early diagnosis of Candida and prompt treatment with appropriate antifungal agents, such as fluconazole, amphotericin B deoxycholate, and micafungin, are critical for improved outcomes. This paper reviews the current literature relating to the prevention, diagnosis, and treatment of Candida infections in the neonatal intensive care unit.

Prevalence and safety of diazoxide in the neonatal intensive care unit

OBJECTIVE

Diazoxide is used to treat infants with persistent hypoglycemia, but the prevalence of its use and adverse effects are not well described. We report demographic and clinical characteristics of infants treated with diazoxide in neonatal intensive care units (NICUs).

STUDY DESIGN

Retrospective cohort study of infants 24-41 weeks' gestation admitted to 392 NICUs from 1997-2016, comparing characteristics between hypoglycemic infants exposed/not exposed to diazoxide. For diazoxide courses > 1 day, we report percentages of infants starting diuretics and/or developing new ventilator/oxygen requirement during therapy.

RESULTS

Among 1,249,466 infants, 185,832 had hypoglycemia; 1066/185,832 (0.57%) received diazoxide. Diazoxide use increased over time (P = 0.001). Infants receiving diazoxide varied from 0-14.9% among centers. New diuretic courses were associated with 91/664 (14%), and new oxygen or ventilator requirement during therapy was associated with 64/556 (12%) and 34/647 (5%), respectively.

CONCLUSIONS

Diazoxide use in NICU settings has increased over time. Infants receiving diazoxide commonly received diuretics.

Probiotic Use and Safety in the Neonatal Intensive Care Unit: A Matched Cohort Study

OBJECTIVE

To determine the prevalence of probiotic administration in infants born preterm over time, as well as the association between probiotic administration and select adverse outcomes.

STUDY DESIGN

We performed a multicenter cohort study of infants 23-29 weeks of gestational age admitted to 289 neonatal intensive care units from 1997 to 2016. We evaluated the type of probiotics given and prevalence of exposure to probiotics over time and by site. We matched infants exposed to probiotics by several factors to unexposed infants receiving enteral feeds on the same postnatal day. We performed conditional logistic regression to evaluate the association between probiotics exposure and adverse outcomes, including necrotizing enterocolitis (NEC), bloodstream infections, meningitis, and death.

RESULTS

Of 78 076 infants, 3626 (4.6%) received probiotics. Probiotic use increased over the study period and varied among neonatal intensive care units. We matched 2178 infants exposed to probiotics to 33 807 without exposure. Probiotic administration was associated with a decrease in NEC (OR 0.62, 95% CI 0.48-0.80) and death (OR 0.52, 95% CI 0.39-0.70), an increase in Candida infection (OR 2.23, 95% CI 1.29-3.85), but no increase in bloodstream infection (OR 0.86, 95% CI 0.70-1.05) or meningitis (OR 1.18, 95% CI 0.40-3.46).

CONCLUSIONS

Probiotic use increased over time and was associated with decreased odds of NEC and death. Prospective, randomized-controlled studies of specific probiotic products are needed to further investigate the safety and efficacy of probiotics in preterm infants.

Early sepsis does not increase the risk of late sepsis in very low birth weight neonates

OBJECTIVE

To examine whether preterm very low birth weight (VLBW) infants have an increased risk of late-onset sepsis (LOS) following early-onset sepsis (EOS).

STUDY DESIGN

Retrospective analysis of VLBW infants (401-1500 g) born September 1998 through December 2009 who survived >72 hours and were cared for within the National Institute of Child Health and Human Development Neonatal Research Network. Sepsis was defined by growth of bacteria or fungi in a blood culture obtained ≤ 72 hours of birth (EOS) or >72 hours (LOS) and antimicrobial therapy for ≥ 5 days or death <5 days while receiving therapy. Regression models were used to assess risk of death or LOS by 120 days and LOS by 120 days among survivors to discharge or 120 days, adjusting for gestational age and other covariates.

RESULTS

Of 34,396 infants studied, 504 (1.5%) had EOS. After adjustment, risk of death or LOS by 120 days did not differ overall for infants with EOS compared with those without EOS [risk ratio (RR): 0.99 (0.89-1.09)] but was reduced in infants born at <25 weeks gestation [RR: 0.87 (0.76-0.99), P = .048]. Among survivors, no difference in LOS risk was found overall for infants with versus without EOS [RR: 0.88 (0.75-1.02)], but LOS risk was reduced in infants with birth weight 401-750 g who had EOS [RR: 0.80 (0.64-0.99), P = .047].

CONCLUSIONS

Risk of LOS after EOS was not increased in VLBW infants. Surprisingly, risk of LOS following EOS appeared to be reduced in the smallest, most premature infants, underscoring the need for age-specific analyses of immune function.

Improved neurodevelopmental outcomes following long-term high-dose oral acyclovir therapy in infants with central nervous system and disseminated herpes simplex disease

OBJECTIVE

Infants with neonatal herpes, classified as central nervous system or disseminated disease, have a high incidence of moderate and severe neurologic deficits despite standard acute therapy.

STUDY DESIGN

Following completion of parenteral therapy, infants with central nervous system and/or disseminated disease received 2 years of continuous oral acyclovir therapy. Target minimum peak serum acyclovir concentrations were >2 microg/ml for the first three patients, and >3 microg/ml for the subsequent 13 patients. Safety assessments were made every 3 months. We evaluated neurodevelopmental outcomes with Bayley Scales of Infant Development.

RESULTS

A total of 16 consecutive herpes simplex virus-infected infants born during 1990 to 2003 received the treatment plan; 13/16 infants had central nervous system disease; 3 had disseminated disease without central nervous system involvement. A total of 69% (11/16) had Bayley scores in the normal range for mental development and 79% (11/14) had motor scores in the normal range. At the final assessment, five children had developmental delays. One child had severe mental delay with normal motor development. Four children had mild mental delays, with severe motor delays in three. All children were independently mobile, without seizure disorder, had normal vision, and had speech development. During the 2-year course of treatment, five children had brief recurrences of dermal lesions, and none had evidence of neurologic deterioration. There were no serious or sustained adverse drug reactions.

CONCLUSION

This pilot study reports improved outcomes in a small cohort of infants with a prolonged course of oral acyclovir. A minority of these children exhibited mild or significant developmental delays. Further investigation of this approach to treatment is warranted.

Invasive Candida infections in the neonate

Advances in medical therapy have increased premature infant survival. A rise in Candida infections in neonatal intensive care units (NICUs) has followed. Once considered a contaminant, Candida is now recognized as a major cause of mortality and morbidity within these units. We will examine what is known about the epidemiology, risk factors and end-organ involvement of Candida infections with a focus on invasive disease. In addition, diagnostic alternatives to traditional blood culture, experience with antifungal agents for prophylaxis and therapeutic options, including newer antifungal agents, will be presented.

Timing of Multiorgan Dysfunction among Hospitalized Infants with Fatal Fulminant Sepsis

Objective Identify the progression of specific signs of multiorgan dysfunction among infants with fatal sepsis. Study Design Cohort study of 679 infants who died within 3 days of the start of a late-onset sepsis (LOS) episode in neonatal intensive care units from 1997 to 2012. We extracted clinical and laboratory data on the day of death (day 0) and the preceding 5 days (days -5 to -1). Results Median (25th percentile-75th percentile) gestational age was 25 (24-28) weeks. Compared with day -1, day 0 was characterized by an increased requirement for mechanical ventilation and higher mean fraction of inspired oxygen. Measures of cardiorespiratory support and the proportion of infants with neutropenia began to rise on day -2. Conclusion Hospitalized infants with fatal LOS manifest respiratory, cardiovascular, renal, immune, and hematologic dysfunction. Knowledge of these factors and their timing may be important for the development and testing of novel therapeutics to reduce sepsis mortality.

Population Pharmacokinetics of Fluconazole in Premature Infants with Birth Weights Less than 750 Grams

Fluconazole is an effective agent for prophylaxis of invasive candidiasis in premature infants. The objective of this study was to characterize the population pharmacokinetics (PK) and dosing requirements of fluconazole in infants with birth weights of <750 g. As part of a randomized clinical trial, infants born at <750 g birth weight received intravenous (i.v.) or oral fluconazole at 6 mg/kg of body weight twice weekly. Fluconazole plasma concentrations from samples obtained by either scheduled or scavenged sampling were measured using a liquid chromatography-tandem mass spectrometry assay. Population PK analysis was conducted using NONMEM 7.2. Population PK parameters were allometrically scaled by body weight. Covariates were evaluated by univariable screening followed by multivariable assessment. Fluconazole exposures were simulated in premature infants using the final PK model. A population PK model was developed from 141 infants using 604 plasma samples. Plasma fluconazole PK were best described by a one-compartment model with first-order elimination. Only serum creatinine was an independent predictor for clearance in the final model. The typical population parameter estimate for oral bioavailability in the final model was 99.5%. Scavenged samples did not bias the parameter estimates and were as informative as scheduled samples. Simulations indicated that the study dose maintained fluconazole troughs of >2,000 ng/ml in 80% of simulated infants at week 1 and 59% at week 4 of treatment. Developmental changes in fluconazole clearance are best predicted by serum creatinine in this population. A twice-weekly dose of 6 mg/kg achieves appropriate levels for prevention of invasive candidiasis in extremely premature infants.

Cough in pediatric patients receiving angiotensin-converting enzyme inhibitor therapy or angiotensin receptor blocker therapy in randomized controlled trials

The incidence of cough in children receiving antihypertension therapy with angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs) is unknown. We analyzed patient-level data from eight randomized trials for the treatment of pediatric hypertension, six of them involving ACEis and two involving ARBs. The incidence of cough in children receiving ACEis (reported cough, 3.2%) was similar to that in children receiving ARBs (reported cough, 1.8%) (P = 0.34). Reports of cough were lower in children than in adults.

Simultaneous determination of trimethoprim and sulfamethoxazole in dried plasma and urine spots

BACKGROUND

Trimethoprim-sulfamethoxazole (TMP-SMX) is an antimicrobial drug combination commonly prescribed in children and adults. The study objectives were to validate and apply an HPLC-MS/MS method to quantify TMP-SMX in dried plasma spots (DPS) and dried urine spots (DUS), and perform a comparability analysis with liquid matrices.

RESULTS

For TMP the validated range was 100-50,000 ng/ml for DPS and 500-250,000 ng/ml for DUS; for SMX, the validated range was 1000-500,000 ng/ml for both DPS and DUS. Good agreement was noted between DPS/DUS and liquid plasma and urine samples for TMP, while only modest agreement was observed for SMX in both matrices.

CONCLUSION

A precise, accurate and reproducible method was developed to quantify TMP-SMX in DPS and DUS samples.

Sports medicine and ethics

Physicians working in the world of competitive sports face unique ethical challenges, many of which center around conflicts of interest. Team-employed physicians have obligations to act in the club's best interest while caring for the individual athlete. As such, they must balance issues like protecting versus sharing health information, as well as issues regarding autonomous informed consent versus paternalistic decision making in determining whether an athlete may compete safely. Moreover, the physician has to deal with an athlete's decisions about performance enhancement and return to play, pursuit of which may not be in the athlete's long-term best interests but may benefit the athlete and team in the short term. These difficult tasks are complicated by the lack of evidence-based standards in a field influenced by the lure of financial gains for multiple parties involved. In this article, we review ethical issues in sports medicine with specific attention paid to American professional football.

Electronic Health Records and Pharmacokinetic Modeling to Assess the Relationship between Ampicillin Exposure and Seizure Risk in Neonates

OBJECTIVE

To evaluate the relationship between ampicillin dosing, exposure, and seizures.

STUDY DESIGN

This was a retrospective observational cohort study of electronic health record (EHR) data combined with pharmacokinetic model derived drug exposure predictions. We used the EHR from 348 Pediatrix Medical Group neonatal intensive care units from 1997 to 2012. We included all infants 24-41 weeks gestational age, 500-5400 g birth weight, first exposed to ampicillin prior to 25 days postnatal age. Using a 1-compartment pharmacokinetic model and EHR data, we simulated maximum ampicillin concentration at steady state (Cmaxss, µg/mL) and area under the concentration time curve from 0 to 24 hours (AUC24, µg*h/dL). Using multivariable logistic regression, we evaluated association between ampicillin dosing, exposure, and seizures as documented in the EHR.

RESULTS

We identified 131 723 infants receiving 134 041 courses of ampicillin for 653 506 infant-days of exposure. The median daily dose was 200 mg/kg/d (25th, 75th percentile; 100, 200). Median Cmaxss and AUC24 were 256.6 µg/mL (164.3, 291.5) and 2593 µg*h/dL (1917, 3334). On multivariable analysis, dosing was not associated with seizures. However increasing Cmaxss (OR = 1.10, 95% CI 1.03, 1.17) and AUC24 (OR 1.11, 95% CI 1.05, 1.18) were associated with increased odds of seizures.

CONCLUSIONS

In this cohort of hospitalized infants, higher ampicillin exposure was associated with seizures as documented in the EHR.

Antifungal agents and therapy for infants and children with invasive fungal infections: a pharmacological perspective

Invasive fungal infections, although relatively rare, are life-threatening diseases in premature infants and immunocompromised children. While many advances have been made in antifungal therapeutics in the last two decades, knowledge of the pharmacokinetics and pharmacodynamics of antifungal agents for infants and children remains incomplete. This review summarizes the pharmacology and clinical utility of currently available antifungal agents and discusses the opportunities and challenges for future research.

Neonatal Escherichia coli Bloodstream Infections: Clinical Outcomes and Impact of Initial Antibiotic Therapy

BACKGROUND

Escherichia coli is a common cause of bloodstream infections (BSIs) in infants and is associated with high mortality and morbidity among survivors. The clinical significance of antibiotic resistance and timing of appropriate antimicrobial therapy in this population is poorly understood.

METHODS

We identified all infants with E. coli BSIs discharged from 77 neonatal intensive care units managed by the Pediatrix Medical Group in 2012. We used multivariable logistic regression to evaluate the association between 30-day mortality and ampicillin-resistant E. coli BSI, as well as the number of active empiric antimicrobial agents administered, controlling for gestational age, small-for-gestational age status, early-onset versus late-onset BSI, oxygen requirement, ventilator support and inotropic support on the day of the first positive blood culture.

RESULTS

We identified 258 episodes of E. coli BSI, including 123 (48%) ampicillin-resistant isolates. Unadjusted 30-day mortality did not significantly differ between infants with ampicillin-resistant versus ampicillin-susceptible E. coli BSI [11 of 123 (9%) vs. 7 of 135 (5%); P = 0.33; adjusted odds ratio = 1.37 (95% confidence interval: 0.39, 4.77)]. Among ampicillin-resistant E. coli BSIs, 30-day mortality was not significantly lower for infants treated with at least one empiric antimicrobial active against ampicillin-resistant E. coli versus infants receiving no active empiric agent [adjusted odds ratio = 1.50 (0.07, 33.6)].

CONCLUSIONS

In this population of infants with E. coli BSI, ampicillin resistance was not associated with significantly increased mortality. Among the subset of infants with ampicillin-resistant E. coli, appropriate empirical antibiotic therapy was not associated with lower mortality.

Safety of micafungin in infants: insights into optimal dosing

INTRODUCTION

Invasive Candida infections are a leading cause of mortality and morbidity in neonatal intensive care units (NICUs). Micafungin is a promising therapeutic option for treatment of invasive fungal infections in infants given its safety profile in older children and adults. Understanding micafungin safety in infants is particularly important because antifungals are most often used in premature infants with multiple underlying medical conditions in a critical care setting.

AREAS COVERED

This article reviews the literature evaluating the safety profile of micafungin in infants and offers recommendations for optimal dosing for treatment of invasive candidiasis in the NICU setting. The review has been performed using a Medline search in September 2010 for related articles from 1990 to the present with the Mesh related terms 'micafungin' and 'safety' in combination with the free words 'antifungal', 'candidiasis', 'drug toxicity', 'infant, premature' and 'infant, newborn'.

EXPERT OPINION

Despite the limitations of the existing literature, we believe micafungin dosing of 10 mg/kg/day for all term and preterm infants is a viable treatment option in the NICU setting for management of invasive candidiasis. Although the number of infants for whom safety data are reported is small, higher doses of micafungin appear safe and well tolerated in this population.

Rational testing of the HIV-exposed infant

OBJECTIVES

The objectives of this study were 1) to evaluate testing regimens of human immunodeficiency virus (HIV)-exposed infants and 2) to determine optimal methods of follow-up by enzyme-linked immunosorbent assay (ELISA) testing.

METHODS

We reviewed the results from 742 HIV-exposed infants in the state of North Carolina; 2474 samples were tested for HIV by DNA polymerase chain reaction (PCR) at the University of North Carolina Retrovirology Core Laboratory. We then reviewed the utility and costs of ELISA testing of all HIV-exposed infants who were seen at the Duke University Pediatric Infectious Disease Clinic between January 1, 1993, and May 5, 1998. We used likelihood ratios to model probability of HIV infection given 3 negative DNA (PCR) tests and to provide recommendations on the use of ELISA follow-up.

RESULTS

The overall sensitivity of the DNA PCR was 87.1%, and its specificity was 99.9%. We evaluated 224 HIV-exposed infants who were seen at Duke University and who had at least 3 negative diagnostic tests using either DNA PCR tests or HIV blood cultures. All 178 infants who subsequently underwent ELISA testing ultimately demonstrated seroreversion. The Duke University Pediatric Infectious Disease Clinic transferred the care of 65 patients to primary care physicians before ELISA testing and retained the care of the remaining 159 patients. Children who remained in Duke's care were more likely to have documentation of seroreversion (158 of 159 vs 20 of 65). We reviewed costs of travel, physician appointment, and HIV antibody testing in a tertiary care setting. Given 3 negative PCR tests, the expected cost per case of HIV detected by a positive ELISA assay is $23.8 million.

CONCLUSIONS

Documentation of seroreversion in this cohort was nearly complete in the multidisciplinary subspecialty clinic but not when such responsibility was left to the primary care physician. Given the low probability of disease in patients who have had 3 negative PCR tests, documentation of a negative ELISA may not be an appropriate use of medical resources.