Vancomycin drug monitoring in infants with CoNS sepsis-target attainment, microbiological response and nephrotoxicity

OBJECTIVES

To characterize residual vancomycin concentrations (Cmin) and assess the relationships between Cmin, the risk of nephrotoxicity and persistent CoNS sepsis.

METHODS

In this 5-year retrospective study among infants treated with vancomycin, the primary outcome was the proportion of those with a steady state Cmin between 10 and 20 mg/L. The secondary outcomes were nephrotoxicity and persistent CoNS sepsis.

RESULTS

Of 120 infants included, the median first steady state Cmin was 12.4 mg/L and 77 (64%) had a Cmin between 10 and 20 mg/L. Six percent developed nephrotoxicity. This risk was not associated with Cmin. Of the 30 infants with CoNS sepsis, 17 (57%) had persistent bacteremia, and this risk did not correlate significantly with Cmin, CoNS minimal inhibitory concentration (MIC) for vancomycin, or Cmin/MIC.

CONCLUSIONS

The majority of infants achieved targeted levels of vancomycin, but persistent bacteremia was common. We did not identify a Cmin threshold associated with nephrotoxicity, nor with microbiological clearance.

Effect of fluconazole prophylaxis on Candida fluconazole susceptibility in premature infants

OBJECTIVES

Extremely premature infants are at high risk of developing invasive candidiasis; fluconazole prophylaxis is safe and effective for reducing invasive candidiasis in this population but further study is needed. We sought to better understand the effect of prophylactic fluconazole on a selection of fluconazole-resistant Candida species.

METHODS

We evaluated the susceptibility to fluconazole of Candida isolates from premature infants (<750 g birth weight) enrolled in a multicentre, randomized, placebo-controlled trial of fluconazole prophylaxis. Candida species were isolated through surveillance cultures at baseline (study day 0-7), period 1 (study day 8-28) and period 2 (study day 29-49). Fluconazole MICs were determined for all Candida isolates.

RESULTS

Three hundred and sixty-one infants received fluconazole (n = 188) or placebo (n = 173). After the baseline period, Candida colonization was significantly lower in the fluconazole group compared with placebo during periods 1 (5% versus 27%; P < 0.001) and 2 (3% versus 27%; P < 0.001). After the baseline period, two infants (1%) were colonized with at least one fluconazole-resistant Candida in each group. Median fluconazole MIC was similar in both treatment groups at baseline and period 1. However, in period 2, median MIC was higher in the fluconazole group compared with placebo (1.00 versus 0.50 mg/L, P = 0.01). There was no emergence of resistance observed and no patients developed invasive candidiasis with a resistant Candida isolate.

CONCLUSIONS

Fluconazole prophylaxis decreased Candida albicans and 'non-albicans' Candida colonization and was associated with a slightly higher fluconazole MIC for colonizing Candida isolates.

1601. Effect of Preemptive Rituximab Therapy on Epstein–Barr Reactivation in Allogenic Hematopoietic Stem Cell Pediatric Transplants

Background

Children with Epstein–Barr virus (EBV) viremia after hematopoietic stem cell transplantation (HSCT) are at increased risk of post-transplant lymphoproliferative disease (PTLD). Our aim was to assess whether pre-emptive rituximab reduced EBV-viral load (EBV-VL) and the risk of developing PTLD.

Methods

We retrospectively included all children who had a positive EBV-VL within 12 months after an allogenic HSCT (2007–2015) in a single tertiary pediatric hospital. Whole blood EBV-VL was monitored weekly using a real-time PCR, during the first 100 days after HSCT and then monthly until 6 months post-HSCT or until EBV-VL became undetectable. EBV-VL clearance was defined as two negative EBV-VL at least 1 week apart. Pre-emptive rituximab was defined as a treatment administered before the occurrence of PTLD. We determined the impact of pre-emptive rituximab on EBV-VL clearance, using a marginal structural cox model, adjusting for age at transplant, time between transplant and first positive EBV-VL, in-vivo T-cell depletion at induction, value of EBV-VL at the first dose of rituximab, and the EBV-VL value at the current and previous time point.

Results

Of 214 children who underwent allogenic HSCT, EBV DNA was detected in 87 (41%) children. Children who received rituximab after diagnosis of PTLD were excluded, leading to a cohort of 78 children. Twenty-two (28%) children received pre-emptive rituximab. Mean (SD) age was similar in both groups (10 [5] year). First post-transplant positive EBV-VL was earlier in the pre-emptive rituximab group (mean of 55 [54] vs. 113 [96] days; P < 0.05) and first positive EBV-VL was higher in the pre-emptive rituximab group (mean of 3.4 [0.6] vs. 3.0 [0.6] log₁₀/mL; P < 0.05). In adjusted analyses, pre-emptive rituximab was associated with a higher likelihood of EBV-VL clearance (hazard ratio 1.86; 95% confidence interval 1.10–3.14; Figure 1). Of the 10 children who developed PTLD, none had received pre-emptive rituximab.

Conclusion

EBV viremia is frequent in children with allogenic HSCT. Our results suggest that pre-emptive rituximab is associated with more rapid EBV-VL clearance. The effect of rituximab on the risk of PTLD needs to be better defined.

Disclosures

All authors: No reported disclosures.

Profile of resistance to IVIG treatment in patients with Kawasaki disease and concomitant infection

INTRODUCTION

Kawasaki disease (KD) can be associated with concomitant viral or bacterial infections. Children with persistent or recurrent fever 36 hours after the end of intravenous immunoglobulin (IVIG) are considered to be resistant to treatment and are at increased risk for coronary complications. Although concomitant infection does not affect coronary outcome, it is unknown how it influences the response to IVIG treatment.

METHODOLOGY

Retrospective cohort study between 2008 and 2016 in a tertiary pediatric university hospital, including 154 children, of which 59 (38%) had concomitant infection.

RESULTS

Children with concomitant infection were more likely to have fever 48 hours after initial IVIG treatment (36% vs 20%, p = 0.05) and to be treated with a second dose (33% vs 18%, p = 0.04). Children with infection had higher C-reactive protein at the time of diagnosis (148 vs 112 mg/L, p = 0.04), and 48 hours after IVIG administration (111 vs 59 mg/L, p = 0.003). Nevertheless, there was no statistically significant difference in the prevalence of coronary complications (Z-score > 2.5) between children with and without concomitant infection (36% vs 39%, p = 0.68).

CONCLUSION

Children with KD and concomitant infection are more likely to have persistent fever and elevated inflammatory markers after treatment. This association increases the likelihood of receiving a second dose of IVIG but not the risk of coronary complication. Accordingly, prospective studies to distinguish true IVIG resistance from infection induced persistent fever is warranted.

Antifungal Susceptibility and Clinical Outcome in Neonatal Candidiasis

BACKGROUND

Invasive candidiasis is an important cause of sepsis in extremely low birth weight infants (ELBW, < 1000 g), is often fatal, and frequently results in neurodevelopmental impairment (NDI) among survivors. We sought to assess the antifungal minimum inhibitory concentration (MIC) distribution for Candida in ELBW infants and evaluate the association between antifungal resistance and death or NDI.

METHODS

This was a secondary analysis of a National Institute of Child Health and Human Development Neonatal Research Network study. MIC values were determined for fluconazole, amphotericin B and micafungin. NDI was assessed at 18-22 months adjusted age using the Bayley Scales of Infant Development. An infant was defined as having a resistant Candida isolate if ≥ 1 positive cultures from normally sterile sites (blood, cerebrospinal fluid, or urine) were resistant to ≥ 1 antifungal agent. In addition to resistance status, we categorized fungal isolates according to MIC values (low and high). The association between death/NDI and MIC level was determined using logistic regression, controlling for gestational age and Bayley Scales of Infant Development (II or III).

RESULTS

Among 137 ELBW infants with IC, MICs were determined for 308 isolates from 110 (80%) infants. Three Candida isolates from 3 infants were resistant to fluconazole. None were resistant to amphotericin B or micafungin. No significant difference in death, NDI, or death/NDI between groups with low and high MICs was observed.

CONCLUSIONS

Antifungal resistance was rare among infecting Candida isolates, and MIC level was not associated with increased risk of death or NDI in this cohort of ELBW infants.

Assessing effect of catheter type and position on central line-associated bloodstream infections in the NICU

BACKGROUND

Central venous catheter usage in NICU remains associated with serious complications such as bloodstream infection. Also, low position (underdiaphragmatic) of umbilical venous catheter (UVC) is tolerated despite not recommended. To our knowledge, no previous study assessed the effect of such a position on central line associated bloodstream infections (CLABSI) rates in the NICU.

OBJECTIVES

The primary objectives of this study were to assess global CLABSI rates for each central catheter subtype and position, and specific rates according to birth weight and gestational age. Dwell time before infection and microorganisms involved were also evaluated.

DESIGN/METHODS

For this retrospective cohort study, all neonates hospitalized in Level 3 NICU, from April 1st 2011 to March 31st 2016, in whom a central line was inserted, were included. Data about catheter insertion, demographic characteristics and bloodstream infections was extracted from local CVC database, local CLABSI database, patient medical record, post catheter insertion X-rays and Canadian Neonatal Network database. Difference in CLABSI rates and type of microorganisms involved were analyzed using Cox regression and Chi2. Difference in dwell time was analyzed using a one-way ANOVA and evolution in time of the proportion of each type of catheter presented as observational data.

RESULTS

A total of 1577 neonates were included and 2440 CVC were studied. Median gestational age (GA) was 30 2/7 [26 6/, 37] weeks and birth weight (BW) was 1310 [680, 2796] g. Of the 2440 neonates, 1308 were boys (53.6%). There was a total of 197 CLABSI. Total number of catheter days over the study period was 23 479 days. CLABSI rate for high UVC was 11.49 per 1000 catheter days compared to 6.92 for PICC line (p < 0.001) and 5.14 for femoral CVC (p = 0.008). CLABSI rate for low UVC was 17.31 per 1000 catheter days (p = 0.002 when compared to high UVC). Median dwell time before infection is 7 days for high UVC, 5 days for low UVC and 11 days for PICC (p < 0.001). Microorganism involved in CLABSI was a majority of Coagulase-negative Staphylococcus in 57.1–71.9% without a statistically significant difference between groups (p= 0.33).

CONCLUSION

Evolution of CVC usage over years remained stable. CLABSI rates are significantly higher with all UVC compared with PICC line and femoral CVC, particularly for newborn < 1500g and < 32 weeks of GA. Low UVC are associated to higher CLABSI rates than high UVC. Health professionals should be cautious with indwelling UVC, especially when in low position. They might conisder replacing low lines by a PICC as soon as possible.

A PAN-CANADIAN STUDY ON THE COMPOUNDED MEDICINES MOST IN NEED OF COMMERCIALIZED ORAL PEDIATRIC FORMULATIONS

BACKGROUND

A large number of drugs administered to children have no commercially available formulations. As a result, health care providers and parents manipulate dosage forms designed for adults. Although compounding is essential to increase access to medicines for children, it can result in adverse events or therapeutic failure. There is an urgent need to undertake a mapping of the needs for child-friendly medicines in Canada.

OBJECTIVES

To determine: 1) the most frequently compounded medicines in Canadian paediatric hospitals; 2) the challenges associated with drug compounding; and 3) medicines most in need of commercialized oral paediatric formulations.

DESIGN/METHODS

Sixteen Canadian paediatric academic hospitals were contacted to participate in a telephone survey including 12 open-, close-ended or Likert-scale questions.

RESULTS

Thirteen centers participated in the survey (81.3%). Fifty-three drugs were identified as most in need of a commercialized oral paediatric formulation. Of those, 12 were reported by ≥4 hospitals as a priority (Table). The most frequently reported compounding challenges were: lack of standardization, bad taste, lack of awareness of prescribers, stability of the formulation, and availability of compounding pharmacies.

CONCLUSION

This study highlights which drugs are most needed for paediatric oral formulations in Canada. For compounded medicines with paediatric formulations available in other countries we are currently assessing their adequacy and partnering with pharmaceutical industry to bring them to the Canadian market. As for those medicines without paediatric formulations in Canada or abroad we are looking for partners interested in developing such formulations. Furthermore, harmonized regulations and data-sharing should be pursued to facilitate access to child-friendly medicines.

PROFILE OF RESISTANCE TO IVIG TREATMENT IN PATIENT WITH KAWASAKI DISEASE AND CONCOMITANT INFECTION

BACKGROUND

Kawasaki disease (KD) is a paediatric systemic vasculitis that can be associated with concomitant viral or bacterial infections. Patients with persistent or recurrent fever 36 hours after the end of intravenous immunoglobulin (IVIG) are considered to be resistant to treatment and are at increased risk for coronary complications.

OBJECTIVES

However, it is unknown how concomitant infection influences the response to IVIG treatment. The aim of this study was to determine the impact of concurrent infection on the prevalence of IVIG resistance and coronary outcome.

DESIGN/METHODS

Retrospective study of 154 children (mean age at diagnosis: 3.4 ± 2.8 years) diagnosed with KD, between 2008–2016 in a tertiary paediatric university hospital, of which 59 (38%) had concomitant infection.

RESULTS

Delay in diagnosis (>10 days of fever) was similar between patients with and without concomitant infection (7% vs 7%, p=0.89). Patients with concomitant infection were more likely to have fever 48 hours after initial treatment (36% vs 20%, p=0.05) and to be treated with a second dose of IVIG (33% vs 18%, p=0.04). Patients with infection had higher C-reactive protein at the time of diagnosis (148 vs 112 mg/L, p=0.04), which persisted after IVIG administration (111 vs 59 mg/L at 48 hours, p=0.003). However, there was no statistically significant difference in the prevalence of coronary artery (CA) complications (coronary artery Z-score > 2.5) between patients with and without concomitant infection (36% vs 39%, p=0.68).

CONCLUSION

Children with KD and concomitant infection are more likely to have persistent fever and elevated inflammatory markers after treatment requiring a second dose of IVIG. Nevertheless, this is not associated with an increased risk of CA complications. Larger scale studies are needed to help distinguish IVIG resistance from infection in children with persistent fever and guide management of this population.

Table/Chart or graphic upload

Population Pharmacokinetics of Trimethoprim-Sulfamethoxazole in Infants and Children

Trimethoprim (TMP)-sulfamethoxazole (SMX) is used to treat various types of infections, including community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) and Pneumocystis jirovecii infections in children. Pharmacokinetic (PK) data for infants and children are limited, and the optimal dosing is not known. We performed a multicenter, prospective PK study of TMP-SMX in infants and children. Separate population PK models were developed for TMP and SMX administered by the enteral route using nonlinear mixed-effects modeling. Optimal dosing was determined on the basis of the matching adult TMP exposure and attainment of the surrogate pharmacodynamic (PD) target for efficacy, a free TMP concentration above the MIC over 50% of the dosing interval. Data for a total of 153 subjects (240 samples for PK analysis) with a median postnatal age of 8 years (range, 0.1 to 20 years) contributed to the analysis for both drugs. A one-compartment model with first-order absorption and elimination characterized the TMP and SMX PK data well. Weight was included in the base model for clearance (CL/F) and volume of distribution (V/F). Both TMP and SMX CL/F increased with age. In addition, TMP and SMX CL/F were inversely related to the serum creatinine and albumin concentrations, respectively. The exposure achieved in children after oral administration of TMP-SMX at 8/40 mg/kg of body weight/day divided into administration every 12 h matched the exposure achieved in adults after administration of TMP-SMX at 320/1,600 mg/day divided into administration every 12 h and achieved the PD target for bacteria with an MIC of 0.5 mg/liter in >90% of infants and children. The exposure achieved in children after oral administration of TMP-SMX at 12/60 and 15/75 mg/kg/day divided into administration every 12 h matched the exposure achieved in adults after administration of TMP-SMX at 640/3,200 mg/day divided into administration every 12 h in subjects 6 to <21 years and 0 to <6 years of age, respectively, and was optimal for bacteria with an MIC of up to 1 mg/liter.

Posaconazole Plasma Monitoring in Immunocompromised Children

Plasma posaconazole exposure was assessed in 13 children who underwent a hematopoietic stem cell transplant. The median dosage was 12.5 mg/kg per day, divided into 3 doses. Of these 13 patients, 46.2% (6) and 30.8% (4) achieved concentrations higher than 0.7 and 1.25 mg/L, respectively. In children at high risk, a higher dosage might be needed to achieve target concentrations.

Comparative effectiveness of linezolid versus vancomycin as definitive antibiotic therapy for heterogeneously resistant vancomycin-intermediate coagulase-negative staphylococcal central-line-associated bloodstream infections in a neonatal intensive care unit

Objectives

Heterogeneously resistant vancomycin-intermediate coagulase-negative staphylococci (hVICoNS) are emerging pathogens causing central-line-associated bloodstream infections (CLABSIs) in neonatal intensive care unit (NICU) patients. Given the burden of disease associated with CLABSI and the current lack of therapeutic guidelines, we aimed to compare the effectiveness of linezolid versus vancomycin used as the definitive antibiotic therapy for hVICoNS CLABSI.

Methods

We performed a retrospective cohort study of infants with hVICoNS CLABSI from a single NICU between 2009 and 2014, treated with either linezolid or vancomycin as definitive antibiotic therapy. CLABSI duration, early and late recurrence and in-hospital mortality were compared using propensity score-adjusted proportional hazards and logistic regression models.

Results

Of 89 infants with hVICoNS CLABSI, 33 (37.1%) treated with linezolid were compared with 56 (62.9%) treated with vancomycin. The median duration of CLABSI was 5 (range 1-12) versus 4 days (range 0-14) ( P  =   0.11), early recurrences were 3.0% versus 7.1% ( P  =   0.42), late recurrences 0% versus 14.3% ( P  =   0.02) and mortality 27.3% versus 28.6% ( P  =   0.90), when treated with linezolid versus vancomycin, respectively. When adjusting using a continuous propensity score, linezolid had an HR of 0.78 (95% CI 0.48-1.27) for CLABSI duration, an OR of 0.23 (95% CI 0.02-2.56) for early recurrence and an OR of 0.9 (95% CI 0.3-2.67) for mortality, relative to vancomycin.

Conclusions

There was no statistically significant difference between linezolid and vancomycin when used as definitive treatment for hVICoNS CLABSI in NICU patients, in terms of CLABSI duration, recurrence or all-cause mortality.

Safety and Ergogenic Properties of Combined Aminophylline and Ambrisentan in Hypoxia

We hypothesized that concomitant pharmacological inhibition of the endothelin and adenosine pathway is safe and improves exercise performance in hypoxic humans, via a mechanism that does not involve augmentation of blood oxygenation. To test this hypothesis, we established safety and drug interactions for aminophylline (500 mg) plus ambrisentan (5 mg) in normoxic volunteers. Subsequently, a placebo-controlled study was employed to test the combination in healthy resting and exercising volunteers at simulated altitude (4,267 m). No serious adverse events occurred. Drug interaction was minimal or absent. Aminophylline alleviated hypoxia-induced headaches. Aminophylline, ambrisentan, and their combination all significantly (P < 0.05 vs. placebo) improved submaximal hypoxic exercise performance (19.5, 20.6, and 19.1% >placebo). Single-dose ambrisentan increased blood oxygenation in resting, hypoxic subjects. We conclude that combined aminophylline and ambrisentan offer promise to safely increase exercise capacity in hypoxemic humans without relying on increasing blood oxygen availability.

Dose-Exposure Simulation for Piperacillin-Tazobactam Dosing Strategies in Infants and Young Children

BACKGROUND

Extended piperacillin-tazobactam (TZP) infusions have been associated with favourable outcomes. There are currently no pediatric dosing recommendations.

OBJECTIVES

To determine appropriate TZP dosing strategies in children 2 months - 6 years according to age and different minimal inhibitory concentrations (MICs).

METHODS

Age and weight were simulated for 1000 children. Post-hoc pharmacokinetic parameter estimates were generated using published clearance and volume of distribution data. For different dosing regimens, we estimated the probability of target attainment (PTA) over a range of MICs from 4 to 128 mg/L. The pharmacodynamic (PD) target was defined as free piperacillin concentrations above the MIC for ≥ 50% of the dosing interval. A PTA ≥ 90% was defined as optimal.

RESULTS

PTA decreased as MIC and age increased. In all age groups, standard dosing regimens (240-300 mg/kg/day, 0.5h infusions) failed to reach PTAs ≥ 90% at MICs ≥ 16 mg/L. Standard 0.5h infusions reached PTAs ≥ 90% at MICs up to 8 mg/L in infants > 2 to 6m. No 0.5h infusion reached PTAs ≥ 90% for MICs ≥ 4 mg/L in children > 6m. While none of the tested regimens were optimal at MICs > 16 mg/L in children > 6m, 100 mg/kg/dose every 6h as a 3h infusion reached PD target at MICs of 32 mg/L in infants > 2 to 6m.

CONCLUSIONS

Up to MICs of 16 mg/L, 90 mg/kg/dose every 8h as a 2h infusion in infants > 2 to 6m and 100 mg/kg/dose every 8h as a 4h infusion in children > 6m-6y achieved PTAs ≥ 90%.

Safety of High-dose Acyclovir in Infants With Suspected and Confirmed Neonatal Herpes Simplex Virus Infections

BACKGROUND

Acyclovir is used to treat herpes simplex virus disease in infants. Treatment with high-dose acyclovir, 60 mg/kg/d, is recommended; however, the safety of this dosage has not been assessed in the past 15 years, and this dosage is not currently approved for infants by the US Food and Drug Administration.

METHODS

We included infants with neonatal herpes simplex virus disease treated with ≥14 days of intravenous acyclovir starting in the first 120 days of life admitted to 1 of 42 neonatal intensive care units managed by the Pediatrix Medical Group between 2002 and 2012. We determined the frequency and proportion of infants with clinical and laboratory adverse events (AEs) as well as the number and proportion of infant days with laboratory AEs occurring during acyclovir exposure.

RESULTS

We identified 89 infants during the study period with 1658 days of acyclovir exposure. Almost all received high-dose acyclovir therapy (79/89, 89%). The most common clinical AEs were hypotension and seizure, both occurring in 9% of infants. Thrombocytopenia was the most common laboratory AE occurring in 25% of infants and on 9% of infant-days. Elevated creatinine occurred in 2% of infants and 0.2% of infant-days and no infants developed renal failure requiring dialysis. Overall, 45% of infants had ≥1 AE.

CONCLUSIONS

In this cohort of infants treated during the high-dose acyclovir era, AEs were common but usually not severe. Many of the AEs reported in this cohort may be related to the underlying infection rather than due to acyclovir exposure.

N-terminal pro-B-type natriuretic peptide diagnostic algorithm versus American Heart Association algorithm for Kawasaki disease

BACKGROUND

Diagnosis of Kawasaki disease (KD) can be challenging in the absence of a confirmatory test or pathognomonic finding, especially when clinical criteria are incomplete. We recently proposed serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) as an adjunctive diagnostic test.

METHODS

We retrospectively tested a new algorithm to help KD diagnosis based on NT-proBNP, coronary artery dilation (CAD) at onset, and abnormal serum albumin or C-reactive protein (CRP). The goal was to assess the performance of the algorithm and compare its performance with that of the 2004 American Heart Association (AHA)/American Academy of Pediatrics (AAP) algorithm.

RESULTS

The algorithm was tested on 124 KD patients with NT-proBNP measured on admission at the present institutions between 2007 and 2013. Age at diagnosis was 3.4 ± 3.0 years, with a median of five diagnostic criteria; and 55 of the 124 patients (44%) had incomplete KD. CA complications occurred in 64 (52%), with aneurysm in 14 (11%). Using this algorithm, 120/124 (97%) were to be treated, based on high NT-proBNP alone for 79 (64%); on onset CAD for 14 (11%); and on high CRP or low albumin for 27 (22%). Using the AHA/AAP algorithm, 22/47 (47%) of the eligible patients with incomplete KD would not have been referred for treatment, compared with 3/55 (5%) with the NT-proBNP algorithm (P < 0.001).

CONCLUSION

This NT-proBNP-based algorithm is efficient to identify and treat patients with KD, including those with incomplete KD. This study paves the way for a prospective validation trial of the algorithm.

Lactic Acidosis with Chloramphenicol Treatment in a Child with Cystic Fibrosis

Children with cystic fibrosis are commonly colonized with multi-resistant bacteria. In such patients, infectious exacerbation may require salvage therapy with uncommonly used antimicrobials, including chloramphenicol. Chloramphenicol is rarely used nowadays because of the associated severe adverse events. We describe the case of a 15-year-old female with terminal cystic fibrosis who required intravenous (IV) chloramphenicol treatment for a Burkholderia cepacia (B. cepacia) exacerbation. The child subsequently developed lactic acidosis and secondary respiratory compensation adding to her baseline respiratory distress. Based on the Naranjo scale, the probability of chloramphenicol being the cause of the hyperlactatemia and associated respiratory distress was rated as probable, as the adverse effects resolved upon discontinuation of the drug. Subsequent genotyping for mitochondrial polymorphism (G3010A) confirmed a possible susceptibility to lactic acidosis from mitochondrial RNA-inhibiting agents such as chloramphenicol. Hyperlactatemia is a rare but life threatening adverse effect that has been previously reported with chloramphenicol exposure, but is not generally thought of. Clinicians should be aware of this potentially life threatening, but reversible adverse event. Lactate should be monitored under chloramphenicol and it should be discontinued as soon as this complication is suspected, especially in patients with low respiratory reserve.

Evaluation of a New Strategy for Clean-Catch Urine in Infants

BACKGROUND AND OBJECTIVES

A new noninvasive bladder stimulation technique has been described to obtain clean-catch urine (CCU) in infants aged <30 days. Objectives were (1) to determine proportion and predictive factors for successful CCU collections using a stimulation maneuver technique among infants <6 months and (2) to determine the proportion of bacterial contamination with this method.

METHODS

A prospective cohort study was conducted in a tertiary pediatric emergency department among infants <6 months needing a urine sample. CCU samples were collected using a standardized stimulation technique. Invasive technique was performed after CCU for three specific conditions. Primary outcomes were proportions of successful CCU specimens and bacterial contamination. We determined associations between successful urine samples and 4 predictive factors (age, sex, low oral intake, and recent voiding).

RESULTS

A total of 126 infants were included (64 boys, median age: 55 days). The CCU procedure was effective in 62 infants (49%; median time: 45 seconds). Infants 0 to 29 days; 30 to 59 days, and 60 to 89 days had more successful procedures, compared with infants >89 days (odds ratios [95% confidence interval (CI)]: 4.3 [1.4 to 13.4]; 3.2 [1.2 to 8.4]; and 4.44 [1.5 to 13.3], respectively). The contamination proportion was 16% (95% CI: 8% to 27%) in the CCU group. This proportion was not statistically different compared with the invasive method group (6%, 95% CI: 3% to 15%).

CONCLUSIONS

The CCU procedure is a quick and effective noninvasive method in children aged <90 days. Contamination proportions were similar to those reported in the literature for urethral catheterization. Circumstances for which the CCU procedure could be performed are proposed.

Staphylococcal infections in infants: updates and current challenges

Staphylococci are common pathogens in the neonatal period. Increased survival of premature infants leads to prolonged hospital stay with associated risk factors for developing invasive staphylococcal disease. Challenges of diagnosing coagulase-negative staphylococcal infections result in conflicting definitions and inconsistent clinical practice. Resistance to methicillin influences the choice of empirical therapy.

Anaerobic antimicrobial therapy after necrotizing enterocolitis in VLBW infants

OBJECTIVE

To evaluate the effect of anaerobic antimicrobial therapy for necrotizing enterocolitis (NEC) on clinical outcomes in very low birth weight (≤1500 g) infants.

METHODS

We identified very low birth weight infants with NEC from 348 US NICUs from 1997 to 2012. Anaerobic antimicrobial therapy was defined by antibiotic exposure on the first day of NEC. We matched (1:1) infants exposed to anaerobic antimicrobial therapy with infants who were not exposed by using a propensity score stratified by NEC severity (medical and surgical). The primary composite outcome was in-hospital death or intestinal stricture. We assessed the relationship between anaerobic antimicrobial therapy and outcome by using a conditional logistic regression on the matched cohort.

RESULTS

A total of 1390 infants exposed to anaerobic antimicrobial therapy were matched with 1390 infants not exposed. Mean gestational age and birth weight were 27 weeks and 946 g, respectively, and were similar in both groups. We found no significant difference in the combined outcome of death or strictures, but strictures as a single outcome were more common in the anaerobic antimicrobial therapy group (odds ratio 1.73; 95% confidence interval, 1.11-2.72). Among infants with surgical NEC, mortality was less common with anaerobic antimicrobial therapy (odds ratio 0.71; 95% confidence interval, 0.52-0.95).

CONCLUSIONS

Anaerobic antimicrobial therapy was not associated with the composite outcome of death or strictures but was associated with an increase in intestinal strictures. This higher incidence of intestinal strictures may be explained by the fact that death is a competing outcome for intestinal strictures, and mortality was slightly lower in the anaerobic cohort. Infants with surgical NEC who received anaerobic antimicrobial therapy had lower mortality.