Clinical practice guidelines for the management of candidiasis: 2009 update by the Infectious Diseases Society of America

Guidelines for the management of patients with invasive candidiasis and mucosal candidiasis were prepared by an Expert Panel of the Infectious Diseases Society of America. These updated guidelines replace the previous guidelines published in the 15 January 2004 issue of Clinical Infectious Diseases and are intended for use by health care providers who care for patients who either have or are at risk of these infections. Since 2004, several new antifungal agents have become available, and several new studies have been published relating to the treatment of candidemia, other forms of invasive candidiasis, and mucosal disease, including oropharyngeal and esophageal candidiasis. There are also recent prospective data on the prevention of invasive candidiasis in high-risk neonates and adults and on the empiric treatment of suspected invasive candidiasis in adults. This new information is incorporated into this revised document.

Prolonged duration of initial empirical antibiotic treatment is associated with increased rates of necrotizing enterocolitis and death for extremely low birth weight infants

OBJECTIVES

Our objectives were to identify factors associated with the duration of the first antibiotic course initiated in the first 3 postnatal days and to assess associations between the duration of the initial antibiotic course and subsequent necrotizing enterocolitis or death in extremely low birth weight infants with sterile initial postnatal culture results.

METHODS

We conducted a retrospective cohort analysis of extremely low birth weight infants admitted to tertiary centers in 1998-2001. We defined initial empirical antibiotic treatment duration as continuous days of antibiotic therapy started in the first 3 postnatal days with sterile culture results. We used descriptive statistics to characterize center practice, bivariate analyses to identify factors associated with prolonged empirical antibiotic therapy (> or =5 days), and multivariate analyses to evaluate associations between therapy duration, prolonged empirical therapy, and subsequent necrotizing enterocolitis or death.

RESULTS

Of 5693 extremely low birth weight infants admitted to 19 centers, 4039 (71%) survived >5 days, received initial empirical antibiotic treatment, and had sterile initial culture results through the first 3 postnatal days. The median therapy duration was 5 days (range: 1-36 days); 2147 infants (53%) received prolonged empirical therapy (center range: 27%-85%). Infants who received prolonged therapy were less mature, had lower Apgar scores, and were more likely to be black. In multivariate analyses adjusted for these factors and center, prolonged therapy was associated with increased odds of necrotizing enterocolitis or death and of death. Each empirical treatment day was associated with increased odds of death, necrotizing enterocolitis, and the composite measure of necrotizing enterocolitis or death.

CONCLUSION

Prolonged initial empirical antibiotic therapy may be associated with increased risk of necrotizing enterocolitis or death and should be used with caution.

10 x '20 Progress--development of new drugs active against gram-negative bacilli: an update from the Infectious Diseases Society of America

Infections caused by antibiotic-resistant bacteria, especially the "ESKAPE" pathogens, continue to increase in frequency and cause significant morbidity and mortality. New antimicrobial agents are greatly needed to treat infections caused by gram-negative bacilli (GNB) resistant to currently available agents. The Infectious Diseases Society of America (IDSA) continues to propose legislative, regulatory, and funding solutions to this continuing crisis. The current report updates the status of development and approval of systemic antibiotics in the United States as of early 2013. Only 2 new antibiotics have been approved since IDSA's 2009 pipeline status report, and the number of new antibiotics annually approved for marketing in the United States continues to decline. We identified 7 drugs in clinical development for treatment of infections caused by resistant GNB. None of these agents was included in our 2009 list of antibacterial compounds in phase 2 or later development, but unfortunately none addresses the entire spectrum of clinically relevant GNB resistance. Our survey demonstrates some progress in development of new antibacterial drugs that target infections caused by resistant GNB, but progress remains alarmingly elusive. IDSA stresses our conviction that the antibiotic pipeline problem can be solved by the collaboration of global leaders to develop creative incentives that will stimulate new antibacterial research and development. Our aim is the creation of a sustainable global antibacterial drug research and development enterprise with the power in the short term to develop 10 new, safe, and efficacious systemically administered antibiotics by 2020 as called for in IDSA's "10 × '20 Initiative."

Neonatal candidiasis among extremely low birth weight infants: risk factors, mortality rates, and neurodevelopmental outcomes at 18 to 22 months

BACKGROUND

Neonatal candidiasis is associated with substantial morbidity and mortality rates. Neurodevelopmental follow-up data for a large multicenter cohort have not been reported.

METHODS

Data were collected prospectively for neonates born at <1000 g at National Institute of Child Health and Human Development-sponsored Neonatal Research Network sites between September 1, 1998, and December 31, 2001. Uniform follow-up evaluations, including assessments of mental and motor development with the Bayley Scales of Infant Development II, were completed for all survivors at corrected ages of 18 to 22 months. We evaluated risk factors for the development of neonatal candidiasis, responses to antifungal therapy, and the association between candidiasis and subsequent morbidity and death.

RESULTS

The cohort consisted of 4579 infants; 320 of 4579 (7%) developed candidiasis; 307 of 320 had Candida isolated from blood, 27 of 320 had Candida isolated from cerebrospinal fluid, and 13 (48%) of 27 of those with meningitis had negative blood cultures. In multivariate analysis of risk factors on day of life 3, birth weight, cephalosporins, gender, and lack of enteral feeding were associated with development of candidiasis. After diagnosis, most neonates had multiple positive cultures despite antifungal therapy, and 10% of neonates had candidemia for > or =14 days. Death or neurodevelopmental impairment (NDI) was observed for 73% of extremely low birth weight infants who developed candidiasis. Death and NDI rates were greater for infants who had delayed removal or replacement of central catheters (>1 day after initiation of antifungal therapy), compared with infants whose catheters were removed or replaced promptly.

CONCLUSIONS

Blood cultures were negative for approximately one half of the infants with Candida meningitis. Persistent candidiasis was common. Delayed catheter removal was associated with increased death and NDI rates.

Early and late onset sepsis in very-low-birth-weight infants from a large group of neonatal intensive care units

BACKGROUND

Very-low-birth-weight (VLBW, <1500 g birth weight) infants are at high risk for both early- and late-onset sepsis. Prior studies have observed a predominance of Gram-negative organisms as a cause of early-onset sepsis and Gram-positive organisms as a cause of late-onset sepsis. These reports are limited to large, academic neonatal intensive care units (NICUs) and may not reflect findings in other units. The purpose of this study was to determine the risk factors for sepsis, the causative organisms, and mortality following infection in a large and diverse sample of NICUs.

METHODS

We analysed the results of all cultures obtained from VLBW infants admitted to 313 NICUs from 1997 to 2010.

RESULTS

Over 108,000 VLBW infants were admitted during the study period. Early-onset sepsis occurred in 1032 infants, and late-onset sepsis occurred in 12,204 infants. Gram-negative organisms were the most commonly isolated pathogens in early-onset sepsis, and Gram-positive organisms were most commonly isolated in late-onset sepsis. Early- and late-onset sepsis were associated with increased risk of death controlling for other confounders (odds ratio 1.45 [95% confidence interval [CI] 1.21,1.73], and OR 1.30 [95%CI 1.21, 1.40], respectively).

CONCLUSIONS

This is the largest report of sepsis in VLBW infants to date. Incidence for early-onset sepsis and late-onset sepsis has changed little over this 14-year period, and overall mortality in VLBW infants with early- and late-onset sepsis is higher than in infants with negative cultures.

Early predictors of in-hospital death in infective endocarditis

BACKGROUND

Data on early determinants of outcome in infective endocarditis (IE) are limited. We evaluated the prognostic significance of early clinical characteristics in a large, prospective cohort of patients with IE.

METHODS AND RESULTS

Two hundred sixty-seven consecutive patients with definite or possible IE by modified Duke criteria and echocardiography performed within 7 days of presentation were evaluated. Acute physiology was assessed by the Acute Physiology, Age, Chronic Health Evaluation II (APACHE II) score at the time of presentation, and early heart failure was diagnosed by Framingham criteria. In-hospital mortality rate in the cohort was 19% and similar for patients with definite or possible IE (20% versus 16%, respectively; P=0.464). Independent predictors of death determined by logistic regression modeling were diabetes mellitus (OR 2.48; 95% CI, 1.24 to 4.96), Staphylococcus aureus as causative organism (OR, 2.06; 95% CI, 1.01 to 4.20), APACHE II score (OR, 1.07; 95% CI, 1.01 to 1.12), and embolic event (OR, 2.79; 95% CI, 1.15 to 6.80). Early echocardiographic findings of the Duke criteria were not predictive of death.

CONCLUSIONS

Early in the course of IE, readily available clinical characteristics that reflect the host-pathogen interaction are predictive of in-hospital death. These factors may identify those patients with IE for more aggressive treatment.

Use of Vancomycin or First-Generation Cephalosporins for the Treatment of Hemodialysis-Dependent Patients with Methicillin-Susceptible Staphylococcus aureus Bacteremia

BACKGROUND

Because of its ease of dosing, vancomycin is commonly used to treat methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia in patients undergoing long-term hemodialysis. Clinical outcomes resulting from such a therapeutic strategy have not been well defined.

METHODS

We prospectively identified patients undergoing long-term hemodialysis who received a diagnosis of MSSA bacteremia. Clinical outcomes were grouped according to the predominant antibiotic received during their therapy (vancomycin or a first-generation cephalosporin [cefazolin]). Treatment failure (defined as death or recurrent infection) was determined at 12 weeks after the initial positive blood culture results. A multivariable analysis was used to adjust for confounders.

RESULTS

During an 84-month period, 123 hemodialysis-dependent patients with MSSA bacteremia were identified. Patients receiving vancomycin (n=77) tended to be younger (51 vs. 57 years; P=.06) and had a lower rates of metastatic complications at presentation (11.7% vs. 36.7%; P=.001) than did those receiving cefazolin (n=46). The 2 groups were similar with regard to Acute Physiology and Chronic Health Evaluation II scores, comorbidities, source of infection, type of hemodialysis access, and access removal rates. Treatment failure was more common among patients receiving vancomycin (31.2% vs. 13%; P=.02). In the multivariable analysis, factors independently associated with treatment failure included vancomycin use (odds ratio, 3.53; 95% confidence interval, 1.15-13.45) and retention of the hemodialysis access (odds ratio, 4.99; 95% confidence interval, 1.89-13.76).

CONCLUSIONS

Hemodialysis-dependent patients with MSSA bacteremia treated with vancomycin are at a higher risk of experiencing treatment failure than are those receiving cefazolin. In the absence of patient specific circumstances (e.g., allergy to beta-lactams), vancomycin should not be continued beyond empirical therapy for hemodialysis-dependent patients with MSSA bacteremia.

Infections Due to Aspergillus terreus: A Multicenter Retrospective Analysis of 83 Cases

Current in vitro and in vivo data indicate that invasive aspergillosis due to Aspergillus terreus is resistant to treatment with amphotericin B. Because little clinical data are available to guide therapy, we performed a retrospective cohort study of cases of invasive A. terreus infections from 1997-2002 to determine whether the use of voriconazole, compared with use of other antifungal therapies, led to an improved patient outcome. We analyzed a total of 83 cases of proven or probable invasive A. terreus infection (47% and 53%, respectively). A total of 66.3% of patients (55 of 83) died during management of IA, with 55.8% mortality (19 of 34 patients) in the voriconazole group and 73.4% mortality (36 of 49) in the group that received therapy with other antifungals. By use of Cox proportional hazards modeling, decreased mortality at 12 weeks was observed in those patients who received voriconazole (hazard ratio, 0.29; 95% CI, 0.15-0.56). Voriconazole is likely to be a better treatment choice for A. terreus infection than is a polyene.

Medication use in the neonatal intensive care unit

OBJECTIVE

The aim of the article is to provide an update on medication use in infants admitted to the neonatal intensive care unit (NICU) in the United States and examine how use has changed over time.

STUDY DESIGN

We performed a retrospective review (2005-2010) of a large prospectively collected administrative database.

RESULT

Medications most commonly administered during the study period were ampicillin, gentamicin, caffeine citrate, vancomycin, beractant, furosemide, fentanyl, dopamine, midazolam, and calfactant (56-681 exposures per 1,000 infants). Those with the greatest relative increase in use included azithromycin, sildenafil, and milrinone. Medications with the greatest relative decrease in use included theophylline, metoclopramide, and doxapram.

CONCLUSION

Medication use in the NICU has changed substantially over time, and only 35% of the most commonly prescribed medications are Food and Drug Administration -approved in infants.

The association of third-generation cephalosporin use and invasive candidiasis in extremely low birth-weight infants

OBJECTIVES

Previous studies have shown that incidence of invasive candidiasis varies substantially among centers, and previous use of broad-spectrum antibiotics is a risk factor for candidiasis in extremely low birth-weight infants. Differences in center practices, such as antibiotic strategies and the effects of these strategies on center incidence of candidiasis, are not reflected in assessments of an individual's risk of candidiasis. We evaluated the relationship between empirical antibiotic practices for extremely low birth-weight infants and center incidence of candidiasis.

METHODS

We studied a cohort of extremely low birth-weight infants who survived > or = 72 hours and were admitted to 1 of 12 tertiary centers between 1998 and 2001. Multivariable logistic regression was used to validate previous broad-spectrum antibiotics use as a risk factor for subsequent candidiasis in individual infants. We calculated correlation coefficients to assess the relationship between center incidence of candidiasis with antibiotic practice patterns.

RESULTS

There were 3702 infants from 12 centers included, and 284 (7.7%) developed invasive candidiasis. Broad-spectrum antibiotics use was associated with candidiasis for individual infants. Center candidiasis incidence ranged from 2.4% to 20.4%. Center incidence of candidiasis was correlated with average broad-spectrum antibiotics use per infant and average use of broad-spectrum antibiotics with negative cultures per infant.

CONCLUSIONS

Center incidences of invasive candidiasis differ substantially, and antibiotic practice differences are possible contributors to center variation in candidiasis risk.

Neonatal candidiasis: epidemiology, risk factors, and clinical judgment

OBJECTIVE

Invasive candidiasis is a leading cause of infection-related morbidity and mortality in extremely low birth weight (<1000-g) infants. We quantified risk factors that predict infection in premature infants at high risk and compared clinical judgment with a prediction model of invasive candidiasis.

METHODS

The study involved a prospective observational cohort of infants≤1000 g birth weight at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. At each sepsis evaluation, clinical information was recorded, cultures were obtained, and clinicians prospectively recorded their estimate of the probability of invasive candidiasis. Two models were generated with invasive candidiasis as their outcome: (1) potentially modifiable risk factors; and (2) a clinical model at time of blood culture to predict candidiasis.

RESULTS

Invasive candidiasis occurred in 137 of 1515 (9.0%) infants and was documented by positive culture from ≥1 of these sources: blood (n=96); cerebrospinal fluid (n=9); urine obtained by catheterization (n=52); or other sterile body fluid (n=10). Mortality rate was not different for infants who had positive blood culture compared with those with isolated positive urine culture. Incidence of candida varied from 2% to 28% at the 13 centers that enrolled≥50 infants. Potentially modifiable risk factors included central catheter, broad-spectrum antibiotics (eg, third-generation cephalosporins), intravenous lipid emulsion, endotracheal tube, and antenatal antibiotics. The clinical prediction model had an area under the receiver operating characteristic curve of 0.79 and was superior to clinician judgment (0.70) in predicting subsequent invasive candidiasis.

CONCLUSION

Previous antibiotics, presence of a central catheter or endotracheal tube, and center were strongly associated with invasive candidiasis. Modeling was more accurate in predicting invasive candidiasis than clinical judgment.

Analysis of the impact of early surgery on in-hospital mortality of native valve endocarditis: use of propensity score and instrumental variable methods to adjust for treatment-selection bias

BACKGROUND

The impact of early surgery on mortality in patients with native valve endocarditis (NVE) is unresolved. This study sought to evaluate valve surgery compared with medical therapy for NVE and to identify characteristics of patients who are most likely to benefit from early surgery.

METHODS AND RESULTS

Using a prospective, multinational cohort of patients with definite NVE, the effect of early surgery on in-hospital mortality was assessed by propensity-based matching adjustment for survivor bias and by instrumental variable analysis. Patients were stratified by propensity quintile, paravalvular complications, valve perforation, systemic embolization, stroke, Staphylococcus aureus infection, and congestive heart failure. Of the 1552 patients with NVE, 720 (46%) underwent early surgery and 832 (54%) were treated with medical therapy. Compared with medical therapy, early surgery was associated with a significant reduction in mortality in the overall cohort (12.1% [87/720] versus 20.7% [172/832]) and after propensity-based matching and adjustment for survivor bias (absolute risk reduction [ARR] -5.9%, P<0.001). With a combined instrument, the instrumental-variable-adjusted ARR in mortality associated with early surgery was -11.2% (P<0.001). In subgroup analysis, surgery was found to confer a survival benefit compared with medical therapy among patients with a higher propensity for surgery (ARR -10.9% for quintiles 4 and 5, P=0.002) and those with paravalvular complications (ARR -17.3%, P<0.001), systemic embolization (ARR -12.9%, P=0.002), S aureus NVE (ARR -20.1%, P<0.001), and stroke (ARR -13%, P=0.02) but not those with valve perforation or congestive heart failure.

CONCLUSIONS

Early surgery for NVE is associated with an in-hospital mortality benefit compared with medical therapy alone.

Calcineurin controls growth, morphology, and pathogenicity in Aspergillus fumigatus

Calcineurin is implicated in a myriad of human diseases as well as homeostasis and virulence in several major human pathogenic microorganisms. The fungus Aspergillus fumigatus is a leading cause of infectious death in the rapidly expanding immunocompromised patient population. Current antifungal treatments for invasive aspergillosis are often ineffective, and novel therapeutic approaches are urgently needed. We demonstrate that a mutant of A. fumigatus lacking the calcineurin A (cnaA) catalytic subunit exhibited defective hyphal morphology related to apical extension and polarized growth, which resulted in drastically decreased filamentation. The delta cnaA mutant lacked the extensive lattice of invading hyphae seen with the wild-type and complemented strains. Sporulation was also affected in the delta cnaA mutant, including morphological conidial defects with the absence of surface rodlets and the added presence of disjunctors creating long conidial chains. Infection with the delta cnaA mutant in several distinct animal models with different types of immunosuppression and inoculum delivery led to a profound attenuation of pathogenicity compared to infection with the wild-type and complemented strains. Lung tissue from animals infected with the delta cnaA mutant showed a complete absence of hyphae, in contrast to tissue from animals infected with the wild-type and complemented strains. Quantitative fungal burden and pulmonary infarct scoring confirmed these findings. Our results support the clinical observation that substantially decreasing fungal growth can prevent disease establishment and decrease mortality. Our findings reveal that calcineurin appears to play a globally conserved role in the virulence of several pathogenic fungi and yet plays specialized roles in each and can be an excellent target for therapeutic intervention.

Incidence and Secondary Transmission of SARS-CoV-2 Infections in Schools

BACKGROUND

In an effort to mitigate the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), North Carolina closed prekindergarten through grade 12 public schools to in-person instruction on March 14, 2020. On July 15, 2020, North Carolina's governor announced schools could open via remote learning or a hybrid model that combined in-person and remote instruction. In August 2020, 56 of 115 North Carolina school districts joined The ABC Science Collaborative (ABCs) to implement public health measures to prevent SARS-CoV-2 transmission and share lessons learned. We describe secondary transmission of SARS-CoV-2 within participating school districts during the first 9 weeks of in-person instruction in the 2020-2021 academic year.

METHODS

From August 15, 2020 to October 23, 2020, 11 of 56 school districts participating in ABCs were open for in-person instruction for all 9 weeks of the first quarter and agreed to track incidence and secondary transmission of SARS-CoV-2. Local health department staff adjudicated secondary transmission. Superintendents met weekly with ABCs faculty to share lessons learned and develop prevention methods.

RESULTS

Over 9 weeks, 11 participating school districts had >90 000 students and staff attend school in person. Among these students and staff, 773 community-acquired SARS-CoV-2 infections were documented by molecular testing. Through contact tracing, health department staff determined an additional 32 infections were acquired within schools. No instances of child-to-adult transmission of SARS-CoV-2 were reported within schools.

CONCLUSIONS

In the first 9 weeks of in-person instruction in North Carolina schools, we found extremely limited within-school secondary transmission of SARS-CoV-2, as determined by contact tracing.

Risk factors for hematogenous complications of intravascular catheter-associated Staphylococcus aureus bacteremia

BACKGROUND

The role of both host and pathogen characteristics in hematogenous seeding following Staphylococcus aureus bacteremia is incompletely understood.

METHODS

Consecutive patients with intravascular catheter-associated Staphylococcus aureus bacteremia were prospectively recruited over a 91-month period. The corresponding bloodstream isolates were examined for the presence of 35 putative virulence determinants. Patient and bacterial characteristics associated with the development of hematogenous complications (HCs) (i.e., septic arthritis, vertebral osteomyelitis, or endocarditis) were defined.

RESULTS

HC occurred in 42 (13%) of 324 patients. Patient characteristics at diagnosis that were associated with HC included community onset (relative risk [RR], 2.25; 95% confidence interval [CI], 1.24-4.07; P=.007), increased symptom duration (odds ratio for each day, 1.14; 95% CI, 1.06-1.2; P<.001), presence of a long-term intravascular catheter or noncatheter prosthesis (RR, 4.02; 95% CI, 1.74-9.27; P<.001), hemodialysis dependence (RR, 3.84; 95% CI, 2.08-7.10; P<.001), and higher APACHE II score (P=.02). Bacterial characteristics included sea (RR, 2.03; 95% CI, 1.16-3.55; P=.011) and methicillin-resistant S. aureus (MRSA) (RR, 2.09; 95% CI, 1.19-3.67; P=.015). Subsequent failure to remove a catheter was also associated with HC (RR, 2.28; 95% CI, 1.22-4.27; P=.011). On multivariable analysis, symptom duration, hemodialysis dependence, presence of a long-term intravascular catheter or a noncatheter device, and infection with MRSA remained significantly associated with HC.

CONCLUSIONS

This investigation identifies 4 host- and pathogen-related risk factors for hematogenous bacterial seeding and reaffirms the importance of prompt catheter removal.

Safety and pharmacokinetics of intravenous anidulafungin in children with neutropenia at high risk for invasive fungal infections

Anidulafungin is an echinocandin with activity against Candida species and Aspergillus species. Adult dosages under study are 50 mg/day for esophageal candidiasis and 100 mg/day for invasive candidiasis and aspergillosis. Little is known, however, about the safety and pharmacokinetics of anidulafungin in children. A multicenter, ascending-dosage study of neutropenic pediatric patients was therefore conducted. Patients were divided into two age cohorts (2 to 11 years and 12 to 17 years) and were enrolled into sequential groups to receive 0.75 or 1.5 mg/kg of body weight/day. Blood samples were obtained following the first and fifth doses. Anidulafungin was assayed in plasma, and pharmacokinetic parameters were determined. Safety was assessed using National Cancer Institute (NCI) common toxicity criteria. Pharmacokinetic parameters were determined for 12 patients at each dosage (0.75 mg/kg/day or 1.5 mg/kg/day). Concentrations and drug exposures were similar for patients between age cohorts, and weight-adjusted clearance was consistent across age. No drug-related serious adverse events were observed. One patient had fever (NCI toxicity grade of 3), and one patient had facial erythema, which resolved with slowing the infusion rate. Anidulafungin in pediatric patients was well tolerated and can be dosed based on body weight. Pediatric patients receiving 0.75 mg/kg/day or 1.5 mg/kg/day have anidulafungin concentration profiles similar to those of adult patients receiving 50 or 100 mg/day, respectively.

Neonatal meningitis: what is the correlation among cerebrospinal fluid cultures, blood cultures, and cerebrospinal fluid parameters?

BACKGROUND

Meningitis is a substantial cause of morbidity and mortality in neonates. Clinicians frequently use the presence of positive blood cultures to determine whether neonates should undergo lumbar puncture. Abnormal cerebrospinal fluid (CSF) parameters are often used to predict neonatal meningitis and determine length and type of antibiotic therapy in neonates with a positive blood culture and negative CSF culture.

METHODS

We evaluated the first lumbar puncture of 9111 neonates at > or =34 weeks' estimated gestational age from 150 NICUs, managed by the Pediatrix Medical Group, Inc. CSF culture results were compared with results of blood cultures and CSF parameters (white blood cells [WBCs], glucose, and protein) to establish the concordance of these values in culture-proven meningitis. CSF cultures positive for coagulase-negative staphylococci and other probable contaminants, as well as fungal and viral pathogens, were excluded from analyses.

RESULTS

Meningitis was confirmed by culture in 95 (1.0%) neonates. Of the 95 patients with meningitis, 92 had a documented blood culture. Only 57 (62%) of 92 patients had a concomitant-positive blood culture; 35 (38%) of 92 had a negative blood culture. In neonates with both positive blood and CSF cultures, the organisms isolated were discordant in 2 (3.5%) of 57 cases. In each case, the CSF pathogen required different antimicrobial therapy than the blood pathogen. For culture-proven meningitis, CSF WBC counts of >0 cells per mm3 had sensitivity at 97% and specificity at 11%. CSF WBC counts of >21 cells per mm3 had sensitivity at 79% and specificity at 81%. Culture-proven meningitis was not diagnosed accurately by CSF glucose or by protein.

CONCLUSIONS

Neonatal meningitis frequently occurs in the absence of bacteremia and in the presence of normal CSF parameters. No single CSF value can reliably exclude the presence of meningitis in neonates. The CSF culture is critical to establishing the diagnosis of neonatal meningitis.

Cumulative radiation exposure and cancer risk estimation in children with heart disease

BACKGROUND

Children with heart disease are frequently exposed to imaging examinations that use ionizing radiation. Although radiation exposure is potentially carcinogenic, there are limited data on cumulative exposure and the associated cancer risk. We evaluated the cumulative effective dose of radiation from all radiation examinations to estimate the lifetime attributable risk of cancer in children with heart disease.

METHODS AND RESULTS

Children ≤6 years of age who had previously undergone 1 of 7 primary surgical procedures for heart disease at a single institution between 2005 and 2010 were eligible for the study. Exposure to radiation-producing examinations was tabulated, and cumulative effective dose was calculated in millisieverts. These data were used to estimate lifetime attributable risk of cancer above baseline using the approach of the Committee on Biological Effects of Ionizing Radiation VII. The cohort included 337 children exposed to 13 932 radiation examinations. Conventional radiographs represented 92% of examinations, whereas cardiac catheterization and computed tomography accounted for 81% of cumulative exposure. Overall median cumulative effective dose was 2.7 mSv (range, 0.1-76.9 mSv), and the associated lifetime attributable risk of cancer was 0.07% (range, 0.001%-6.5%). Median lifetime attributable risk of cancer ranged widely depending on surgical complexity (0.006%-1.6% for the 7 surgical cohorts) and was twice as high in females per unit exposure (0.04% versus 0.02% per 1-mSv effective dose for females versus males, respectively; P<0.001).

CONCLUSIONS

Overall radiation exposures in children with heart disease are relatively low; however, select cohorts receive significant exposure. Cancer risk estimation highlights the need to limit radiation dose, particularly for high-exposure modalities.

Naltrexone reverses ethanol-induced dopamine release in the nucleus accumbens in awake, freely moving rats

The effect of the opioid receptor antagonist, naltrexone, on ethanol-induced changes in extracellular dopamine and serotonin in the nucleus accumbens was investigated using in vivo microdialysis in awake, freely moving rats. Locally applied ethanol (5% infused transprobe) resulted in substantial increases in dopamine in dialysate. Administration of naltrexone (cumulative dosing with 0.25-1.0 mg/kg i.p.) during ethanol administration dose-dependently reversed ethanol-induced increases in extracellular dopamine and its metabolite homovanillic acid but not serotonin. These data demonstrate an essential role for the endogenous opioid system in stimulation of dopamine release by ethanol in a brain area associated with reward and support the opioid system as a prime target for pharmacological modulation of the rewarding effects and consumption of ethanol.

HIF-1α Is an Essential Mediator of IFN-γ-Dependent Immunity to Mycobacterium tuberculosis

The cytokine IFN-γ coordinates macrophage activation and is essential for control of pathogens, including Mycobacterium tuberculosis However, the mechanisms by which IFN-γ controls M. tuberculosis infection are only partially understood. In this study, we show that the transcription factor hypoxia-inducible factor-1α (HIF-1α) is an essential mediator of IFN-γ-dependent control of M. tuberculosis infection both in vitro and in vivo. M. tuberculosis infection of IFN-γ-activated macrophages results in a synergistic increase in HIF-1α protein levels. This increase in HIF-1α levels is functionally important, as macrophages lacking HIF-1α are defective for IFN-γ-dependent control of infection. RNA-sequencing demonstrates that HIF-1α regulates nearly one-half of all IFN-γ-inducible genes during infection of macrophages. In particular, HIF-1α regulates production of important immune effectors, including inflammatory cytokines and chemokines, eicosanoids, and NO. In addition, we find that during infection HIF-1α coordinates a metabolic shift to aerobic glycolysis in IFN-γ-activated macrophages. We find that this enhanced glycolytic flux is crucial for IFN-γ-dependent control of infection in macrophages. Furthermore, we identify a positive feedback loop between HIF-1α and aerobic glycolysis that amplifies macrophage activation. Finally, we demonstrate that HIF-1α is crucial for control of infection in vivo as mice lacking HIF-1α in the myeloid lineage are strikingly susceptible to infection and exhibit defective production of inflammatory cytokines and microbicidal effectors. In conclusion, we have identified HIF-1α as a novel regulator of IFN-γ-dependent immunity that coordinates an immunometabolic program essential for control of M. tuberculosis infection in vitro and in vivo.

Comparative safety of amphotericin B lipid complex and amphotericin B deoxycholate as aerosolized antifungal prophylaxis in lung-transplant recipients

BACKGROUND

Aerosolized administrations of amphotericin B deoxycholate (AmBd) and amphotericin B lipid complex (ABLC) in lung transplant recipients were compared for safety and tolerability. The incidence of invasive fungal infections in patients receiving aerosolized amphotericin B formulations as sole prophylaxis was determined.

METHODS

A prospective, randomized (1:1), double-blinded trial was conducted with 100 subjects. AmBd and ABLC were administered postoperatively by nebulizer at doses of 25 mg and 50 mg, respectively, which were doubled in mechanically ventilated patients. The planned treatment was once every day for 4 days, then once per week for 7 weeks. Treatment-related adverse events and invasive fungal infections were quantitated for 2 months after study drug initiation.

RESULTS

Intent-to-treat analysis revealed study drug was discontinued for intolerance in 6 of 49 (12.2%) and 3 of 51 (5.9%) patients in the AmBd- and ABLC-treated groups, respectively (p=0.313). Subjects receiving AmBd were more likely to have experienced an adverse event (odds ratio 2.16, 95% confidence interval 1.10, 4.24, p=0.02). Primary prophylaxis failure within 2 months of study drug initiation was observed in 7 of 49 (14.3%) AmBd-treated patients and 6 of 51 (11.8%) ABLC-treated patients. No fungal pneumonias were observed. Only two (2%) patients experienced documented primary prophylaxis failure with Aspergillus infections within the follow-up period.

CONCLUSIONS

Both aerosol AmBd and ABLC appear to be associated with a low rate of invasive pulmonary fungal infection in the early posttransplant period. Patients receiving ABLC were less likely to experience a treatment-related adverse event.

Neonatal candidemia and end-organ damage: a critical appraisal of the literature using meta-analytic techniques

OBJECTIVE

Neonatal candidemia is an increasing cause of infant morbidity and mortality. We evaluated the current medical literature in an effort to critique the literature and to document the reported prevalences of end-organ damage after neonatal candidemia.

METHODS

We analyzed all peer-reviewed articles of neonatal candidemia published in the English language; inclusion criteria included a cohort limited to all neonatal intensive care unit admissions or all episodes of candidemia in neonates. Articles that also incorporated older patients, did not define a numerator and a denominator for at least 1 form of end-organ damage, included patients from other reports, or did not include all episodes of candidemia in the source population were excluded from the analysis.

RESULTS

Thirty-four articles reported episodes of candidemia and mortality; 21 articles reported prevalence for at least 1 form of end-organ damage. Only 4 (19%) of 21 articles reported prevalence for >4 forms of end-organ damage from the following list: endophthalmitis, meningitis, brain parenchyma invasion, endocarditis, renal abscesses, positive cultures from other normally sterile body fluids, or hepatosplenic abscesses. The median reported prevalence of endophthalmitis was 3% (interquartile range [IQR]: 0%-17%), of meningitis was 15% (IQR: 3%-23%), of brain abscess or ventriculitis was 4% (IQR: 3%-21%), of endocarditis was 5% (IQR: 0%-13%), of positive renal ultrasound was 5% (IQR: 0%-14%), and of positive urine culture was 61% (IQR: 40%-76%). The medical literature concerning end-organ evaluation after episodes of neonatal candidemia is heterogeneous and consists largely of single-center retrospective studies. Year that the data were collected and prevalence of neonates infected with Candida albicans were associated with observed heterogeneity.

CONCLUSIONS

Given the heterogeneity of the medical literature, precise estimates of the frequencies of end-organ damage are not possible and a prospective multicenter trial is warranted, but the data from the published literature suggest that the prevalence of neonates with end-organ damage not only is greater than 0 but also is high enough that until such a prospective trial is completed, end-organ studies should be considered before the conclusion of antifungal therapy.

Bacteremia, central catheters, and neonates: when to pull the line

OBJECTIVES

Physicians who treat neonates who become bacteremic while dependent on central venous catheters face a serious and common dilemma. We sought 1) to evaluate the relationship between central venous catheter removal and outcome in bacteremic neonates, 2) to determine species of bacteria that are associated with an increased risk of infectious complications if the central catheter is not removed promptly, and 3) to provide evidence-based recommendations for central catheter management.

METHOD

A retrospective cohort study of all neonates who had central venous access and developed bacteremia between July 1, 1995, and July 31, 1999, was conducted in the Duke University neonatal intensive care unit.

RESULTS

The outcome for patients in whom the central catheter was not removed within 24 hours of organism identification was significantly worse (odds ratio = 9.8) than it was for those whose catheters were removed promptly. For patients who were infected with Staphylococcus aureus or with nonenteric Gram-negative rods, delayed removal of the central catheter was associated with complicated bacteremia. Catheter sterilization was attempted in 27 neonates who were infected with enteric Gram-negative rods; only 10 of these infants retained their catheters without infection-related complications. Infants who had 4 consecutive blood cultures that were positive for coagulase-negative staphylococcus (CoNS) were at significantly increased risk for end-organ damage and death, compared with infants who had 3 or fewer positive blood culture for CoNS (odds ratio = 29.58).

CONCLUSIONS

Bacteremic infants experienced fewer infection-related complications when the central catheter was removed promptly. One positive blood culture for S aureus or a Gram-negative rod warrants central line removal in a neonate. Clinicians who are faced with a neonate who has 1 positive culture for CoNS may attempt medical management without central catheter removal, but documentation of subsequent negative blood cultures is crucial. Once a neonate has 3 positive blood cultures for CoNS, the central catheter should be removed.central line, neonate, bacteremia, bacteria, umbilical catheter, Broviac, percutaneous.

Empirical therapy for neonatal candidemia in very low birth weight infants

OBJECTIVE

Neonatal candidemia is often fatal. Empirical antifungal therapy is associated with improved survival in neonates and patients with fever and neutropenia. Although guidelines for empirical therapy exist for patients with fever and neutropenia, these do not exist for neonates.

METHODS

A multicenter, retrospective, cohort study was conducted of neonatal intensive care unit patients (N = 6172) who had a blood culture (N = 21,233) after day of life 3 and whose birth weight was <or=1250 g. We performed multivariable conditional logistic regression of risk factors for candidemia. From the regression modeling coefficients, we developed a candidemia score.

RESULTS

In multivariable modeling, thrombocytopenia (odds ratio [OR]: 3.56; 95% confidence interval [CI]: 2.68-4.74) and cephalosporin or carbapenem use in the 7 days before obtaining the blood culture (OR: 1.77; 95% CI: 1.33-2.29) were risk factors for subsequent candidemia. Children who were 25 to 27 weeks' estimated gestational age (OR: 2.02; 95% CI: 1.52-3.05) and children who were born at <25 weeks (OR: 4.15; 95% CI: 3.12-6.29) were at higher risk of developing candidemia than were children who were born at >or=28 weeks. We developed a candidemia score on the basis of the ORs from the multivariable model. Children with a candidemia score >or=2 points were classified as having a "positive" score, and a score of >or=2 points had a sensitivity of 85% and a specificity of 47%.

CONCLUSIONS

We developed a clinical predictive model for neonatal candidemia with high sensitivity and moderate specificity for candidemia. On the basis of our model, when a physician obtains a blood culture, the physician should consider providing antifungal therapy to neonates who are <25 weeks' estimated gestational age and to neonates who have thrombocytopenia at the time of blood culture. In addition, if a physician obtains a blood culture from a child who is 25 to 27 weeks' estimated gestational age and is not thrombocytopenic but has a history of third-generation cephalosporin or carbapenem exposure in the 7 days before the blood culture, then the physician should consider administration of empirical antifungal therapy.