Browsing by Author "Smith, PB"

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    Cytokine gene polymorphisms and the outcome of invasive candidiasis: a prospective cohort study.
    (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2012-02) Johnson, MD; Plantinga, TS; van de Vosse, E; Velez Edwards, DR; Smith, PB; Alexander, BD; Yang, JC; Kremer, D; Laird, GM; Oosting, M; Joosten, LA; van der Meer, JW; van Dissel, JT; Walsh, TJ; Perfect, JR; Kullberg, BJ; Scott, WK; Netea, MG
    BACKGROUND:  Candida bloodstream infections cause significant morbidity and mortality among hospitalized patients. Although clinical and microbiological factors affecting prognosis have been identified, the impact of genetic variation in the innate immune responses mediated by cytokines on outcomes of infection remains to be studied. METHODS:  A cohort of 338 candidemia patients and 351 noninfected controls were genotyped for single-nucleotide polymorphisms (SNPs) in 6 cytokine genes (IFNG, IL10, IL12B, IL18, IL1β, IL8) and 1 cytokine receptor gene (IL12RB1). The association of SNPs with both candidemia susceptibility and outcome were assessed. Concentrations of pro- and antiinflammatory cytokines were measured in in vitro peripheral blood mononuclear cell stimulation assays and in serum from infected patients. RESULTS:  None of the cytokine SNPs studied were associated with susceptibility to candidemia. Persistent fungemia occurred in 13% of cases. In the multivariable model, persistent candidemia was significantly associated with (odds ratio [95% confidence interval]): total parenteral nutrition (2.79 [1.26-6.17]), dialysis dependence (3.76 [1.46-8.64]), and the SNPs IL10 rs1800896 (3.45 [1.33-8.93]) and IL12B rs41292470 (5.36 [1.51-19.0]). In vitro production capacity of interleukin-10 and interferon-γ was influenced by these polymorphisms, and significantly lower proinflammatory cytokine concentrations were measured in serum from patients with persistent fungemia. CONCLUSIONS:  Polymorphisms in IL10 and IL12B that result in low production of proinflammatory cytokines are associated with persistent fungemia in candidemia patients. This provides insights for future targeted management strategies for patients with Candida bloodstream infections.
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    Evaluation of a digital microfluidic real-time PCR platform to detect DNA of Candida albicans in blood.
    (Eur J Clin Microbiol Infect Dis, 2012-09) Schell, WA; Benton, JL; Smith, PB; Poore, M; Rouse, JL; Boles, DJ; Johnson, MD; Alexander, BD; Pamula, VK; Eckhardt, AE; Pollack, MG; Benjamin, DK; Perfect, JR; Mitchell, TG
    Species of Candida frequently cause life-threatening infections in neonates, transplant and intensive care unit (ICU) patients, and others with compromised host defenses. The successful management of systemic candidiasis depends upon early, rapid diagnosis. Blood cultures are the standard diagnostic method, but identification requires days and less than half of the patients are positive. These limitations may be eliminated by using real-time polymerase chain reaction (PCR) to detect Candida DNA in the blood specimens of patients at risk. Here, we optimized a PCR protocol to detect 5-10 yeasts in low volumes of simulated and clinical specimens. We also used a mouse model of systemic candidiasis and determined that candidemia is optimally detectable during the first few days after infection. However, PCR tests are often costly, labor-intensive, and inconvenient for routine use. To address these obstacles, we evaluated the innovative microfluidic real-time PCR platform (Advanced Liquid Logic, Inc.), which has the potential for full automation and rapid turnaround. Eleven and nine of 16 specimens from individual patients with culture-proven candidemia tested positive for C. albicans DNA by conventional and microfluidic real-time PCR, respectively, for a combined sensitivity of 94%. The microfluidic platform offers a significant technical advance in the detection of microbial DNA in clinical specimens.
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    In-hospital outcomes of premature infants with severe bronchopulmonary dysplasia.
    (Journal of perinatology : official journal of the California Perinatal Association, 2017-07) Jackson, W; Hornik, CP; Messina, JA; Guglielmo, K; Watwe, A; Delancy, G; Valdez, A; MacArthur, T; Peter-Wohl, S; Smith, PB; Tolia, VN; Laughon, MM
    OBJECTIVE:To characterize in-hospital outcomes of premature infants diagnosed with severe bronchopulmonary dysplasia (BPD). STUDY DESIGN:Retrospective cohort study including premature infants with severe BPD discharged from 348 Pediatrix Medical Group neonatal intensive care units from 1997 to 2015. RESULTS:There were 10 752 infants with severe BPD, and 549/10 752 (5%) died before discharge. Infants who died were more likely to be male, small for gestational age, have received more medical interventions and more frequently diagnosed with surgical necrotizing enterocolitis, culture-proven sepsis and pulmonary hypertension following 36 weeks of postmenstrual age compared with survivors. Approximately 70% of infants with severe BPD were discharged by 44 weeks of postmenstrual age, and 86% were discharged by 48 weeks of postmenstrual age. CONCLUSIONS:A majority of infants diagnosed with severe BPD were discharged home by 44 weeks of postmenstrual age. These results may inform discussions with families regarding the expected hospital course of infants diagnosed with severe BPD.
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    Prevalence of renal anomalies after urinary tract infections in hospitalized infants less than 2 months of age.
    (J Perinatol, 2010-04) Nowell, L; Moran, C; Smith, PB; Seed, P; Alexander, BD; Cotten, CM; Wiener, JS; Benjamin Jr, DK
    OBJECTIVE: Our aim was to determine the incidence of anatomical abnormalities after a urinary tract infection (UTI) in infants <2 months of age hospitalized in the neonatal intensive care unit (NICU). STUDY DESIGN: This was a retrospective, single-center cohort study of infants <2 months of age in the NICU with a UTI and documented renal imaging. RESULT: We identified 141 infants with UTIs. The mean gestational age and birth weight were 28 weeks and 1254 g, respectively. The most commonly identified pathogen was coagulase-negative Staphylococcus (28%, 44 of 156). A major abnormality was found on at least one imaging study for 4% (5 of 118) of infants. Major abnormalities were noted on 4% (5 of 114) of renal ultrasounds and 2% (2 of 82) of voiding cystourethrography examinations. CONCLUSION: Among infants in the NICU <2 months of age at the time of a UTI, the prevalence of major anatomical abnormalities is <5%.