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Lisa Saiman

Publications and source records attributed to Lisa Saiman.

At least 19 recordsLinked to original sources

Antimicrobial susceptibility and synergy studies of Burkholderia cepacia complex isolated from patients with cystic fibrosis.

Susceptibility (18 antimicrobial agents including high-dose tobramycin) and checkerboard synergy (23 combinations) studies were performed for 2,621 strains of Burkholderia cepacia complex isolated from 1,257 cystic fibrosis patients. Minocycline, meropenem, and ceftazidime were the most active, inhibiting 38%, 26%, and 23% of strains, respectively. Synergy was rarely noted (range, 1% to 15% of strains per antibiotic combination).

Anti-Bacterial Agents↗

Impact of staffing on bloodstream infections in the neonatal intensive care unit.

OBJECTIVE: To examine the association between registered nurse staffing and healthcare-associated bloodstream infections in infants in the neonatal intensive care unit (NICU). DESIGN: Prospective cohort study. SETTING: Two level III-IV NICUs in New York, NY, from March 1, 2001, through January 31, 2003. PARTICIPANTS: A total of 2675 infants admitted to the NICUs for more than 48 hours and all registered nurses who worked in the same NICUs during the study period. Intervention Hours of care provided by registered nurses. Main Outcome Measure Time to first episode of healthcare-associated bloodstream infection. RESULTS: A total of 224 infants had an infection that met the study definition of healthcare-associated bloodstream infection. In a multivariate analysis, after controlling for infants' intrinsic and extrinsic risk factors, a greater number of hours of care provided by registered nurses in NICU 2 was associated with a decreased risk of bloodstream infection in these infants (hazard ratio, 0.21; 95% confidence interval, 0.06-0.79). CONCLUSION: Our findings suggest that registered nurse staffing is associated with the risk of bloodstream infection in infants in the NICU.

Birth Weight↗

Effectiveness of barrier precautions and surveillance cultures to control transmission of multidrug-resistant organisms: a systematic review of the literature.

BACKGROUND: Despite the priority placed on preventing transmission of multidrug-resistant organisms (MDROs) in health care facilities, there is a lack of consensus among recommended infection control guidelines. We focused on control measures that have a great potential to affect patient care, patient services, and hospital cost/resources: barrier precautions/patient isolation and surveillance cultures. METHODS: We conducted a systematic review of the literature and published English-language guidelines pertaining to the use of barrier precautions/patient isolation and surveillance cultures to prevent the transmission of MDROs. The recommendations made by the published guidelines were summarized and compared. The primary research studies identified through our literature search were evaluated for study quality. We then summarized the outcomes of the studies with the highest quality scores and made recommendations for future work. RESULTS: A total of 29 studies were included in our assessment of study quality; of those, 7 studies were of high quality. CONCLUSION: This systematic review identified key gaps in the literature including a need for greater monitoring of implementation of the interventions, more cost analyses of interventions, determining the independent contribution of specific interventions, and identifying the minimum interventions needed to reduce transmission.

Bacteria↗

A low incidence of nontuberculous mycobacterial infections in pediatric hematopoietic stem cell transplantation recipients.

Hematopoietic stem cell transplantation (HSCT) is being used to treat a wide spectrum of clinical disorders but opportunistic infection remains an important factor determining outcomes for these patients. Nontuberculous mycobacterial (NTM) infections are being reported more frequently in HSCT recipients and the incidence of NTM infections in adult recipients is reported to be 0.4%-4.9%. However, the incidence and severity of NTM infections are less well described in pediatric HSCT recipients. Centers for Disease Control and Prevention guidelines were used to define definite and probable NTM infection among 132 children undergoing 169 HSCT between January 2000 and December 2004 at our institution. NTM infection was diagnosed in 5 of 132 pediatric recipients (3.8%). There were no NTM infections diagnosed in the autologous HSCT recipients and the incidence of NTM in allogeneic HSCT recipients was 6.4% (95% confidence interval, 0.8-11.9). The mean age of the HSCT recipients who developed NTM infections was 8 years (range, 2-19 years); 3 were male and 2 were female. Four conditioning regimens included alemtuzumab and 3 had antithymocyte globulin. Of the 5 patients with NTM infections, 2 met the criteria for definite infection and 3 for probable infection. Of the 2 patients with definite NTM infection, 1 had disseminated disease with Mycobacterium avium complex and the other had Mycobacterium chelonae catheter-related bloodstream infection. The probable NTM infections were 1 skin infection with Mycobacterium kansasii and 2 lower respiratory tract infections with M avium complex. Median time to NTM infection was 115 days (range, 14-269 days) after HSCT. Two patients had graft-versus-host disease at the time of NTM infection. All 5 patients received 3-4 antimycobacterial drugs and all NTM infections resolved. In summary, the incidence of NTM infection in pediatric HSCT recipients appears similar to that described in adult HSCT recipients and the outcome appears to be excellent with the proper antibiotic therapy. The increased use of anti-T cell antibodies appears to be associated with an increased risk of NTM infections in pediatric HSCT recipients. Multicenter studies are needed to identify the risk factors, early diagnostic criteria, and optimal therapy.

Adolescent↗

Prevalence of methicillin-sensitive and methicillin-resistant Staphylococcus aureus in pregnant women.

OBJECTIVE: To estimate the extent of Staphylococcus aureus vaginal-rectal colonization among pregnant women as severe S aureus infections have emerged in pregnant and postpartum women and infants. METHODS: We conducted a prospective surveillance study for methicillin-sensitive S aureus and methicillin-resistant S aureus on all routine de-identified vaginal-rectal prenatal group B streptococcus (GBS) screening cultures submitted to the microbiology laboratory of a tertiary-care facility from January to July 2005. Standard microbiologic techniques and molecular analyses were used to detect community-associated methicillin-resistant S aureus strains. As opposed to health care-associated methicillin-resistant S aureus isolates, community-associated methicillin-resistant S aureus isolates were defined as those possessing the type IV or type V staphylococcal chromosomal cassette mec element and usually lacking a multidrug-resistant phenotype. RESULTS: A total of 2,963 GBS screening cultures were analyzed, from which 743 (25.1%, 95% confidence interval [CI] 23.5-26.7%) GBS isolates and 507 (17.1%, 95% CI 15.7-18.5%) S aureus isolates were identified. Group B streptococcus colonization was significantly associated with S aureus colonization (prevalence odds ratio 2.1, 95% CI 1.7-2.5, P < .001). Of the S aureus isolates, 14 (2.8%, 95% CI 1.4-4.2%) were methicillin-resistant, and 13 of these were determined to be community-associated methicillin-resistant S aureus. CONCLUSION: The prevalence of S aureus colonization identified in GBS screening cultures from pregnant women was substantial and associated with GBS co-colonization. Although we do not advocate routine screening of pregnant women for methicillin-sensitive S aureus and methicillin-resistant S aureus colonization, we recommend continued monitoring of both methicillin-sensitive S aureus and methicillin-resistant S aureus infections in this population and their infants.

Anti-Bacterial Agents↗

Risk factors for late onset gram-negative sepsis in low birth weight infants hospitalized in the neonatal intensive care unit.

BACKGROUND: Gram-negative bloodstream infections (BSIs) cause 20-30% of late onset sepsis in neonatal intensive care unit (NICU) patients and have mortality rates of 30-50%. We investigated risk factors for late onset Gram-negative sepsis in very low birth weight (<1500 g) NICU patients. METHODS: We performed a case-control study as part of a larger 2-year clinical trial that examined the effects of hand hygiene practices on hospital-acquired infections. In this substudy, a case was a very low birth weight infant with a hospital-acquired Gram-negative BSI; control subjects, matched on study site and hand hygiene product, were chosen randomly from the patients who did not have Gram-negative BSIs. Potential risk factors were analyzed by Mantel-Haenszel methods and conditional logistic regression. RESULTS: There were 48 cases of Gram-negative BSI. In multivariate analysis, we found that the following variables were significantly associated with Gram-negative BSI: central venous catheterization duration of >10 days; nasal cannula continuous positive airway pressure use; H2 blocker/proton pump inhibitor use; and gastrointestinal tract pathology. CONCLUSIONS: These analyses provide insights into potential strategies to reduce Gram-negative BSIs. Catheters should be removed as possible and H2 blockers/proton pump inhibitors should be used judiciously in NICU patients. The association between nasal cannula continuous positive airway pressure and Gram-negative BSIs requires further investigation. The association of gastrointestinal tract pathology with Gram-negative BSIs identifies a high risk group of neonates who may benefit from enhanced preventative strategies.

Age of Onset↗

Nontuberculous mycobacterial infections in pediatric hematopoietic stem cell transplant recipients: case report and review of the literature.

Nontuberculous mycobacterial (NTM) infections are rarely diagnosed in hematopoietic stem cell transplant (HSCT) recipients. We describe a case of disseminated Mycobacterium avium complex with gastrointestinal tract involvement in a HSCT recipient. We reviewed NTM infections among pediatric HSCT patients at our institution from 2000-2004 and identified 2 additional cases. Fourteen published case reports of NTM disease in children are reviewed.

Adolescent↗

Strategies for prevention of nosocomial sepsis in the neonatal intensive care unit.

PURPOSE OF REVIEW: Infants hospitalized in the neonatal intensive care unit, particularly preterm infants, have very high rates of nosocomial sepsis (also referred to as late onset sepsis or healthcare-associated sepsis). Today's preventive strategies for nosocomial sepsis focus on augmenting the immunologic and functional immaturities of premature infants and ameliorating the risks of extrinsic factors by the use of prophylactic antibiotics and best clinical practices. RECENT FINDINGS: Topical emollients improved neonatal skin condition, but were associated with an increased risk of nosocomial bacterial sepsis and coagulase negative staphylococcal infections, and thus should not be used in extremely-low-birth-weight infants. Single-center studies have shown that probiotics containing anaerobic bacteria may reduce the rate of necrotizing enterocolitis, the severity of necrotizing enterocolitis, and/or bacterial sepsis. Single-center studies have shown that prophylactic fluconazole reduces the rates of invasive candidiasis and/or colonization of extremely-low-birth-weight infants. Quality improvement projects to improve adherence to appropriate hand hygiene and best practices for central venous catheter insertion and maintenance can reduce rates of nosocomial sepsis. SUMMARY: The safety and efficacy of probiotics and prophylactic fluconazole require large multicenter trials. Quality improvement initiatives, however, can be performed now and can reduce the rates of nosocomial sepsis in the neonatal intensive care unit.

Antifungal Agents↗

Compliance of clinical microbiology laboratories in the United States with current recommendations for processing respiratory tract specimens from patients with cystic fibrosis.

Respiratory tract specimens from patients with cystic fibrosis (CF) require unique processing by clinical microbiology laboratories to ensure detection of all potential pathogens. The present study sought to determine the compliance of microbiology laboratories in the United States with recently published recommendations for CF respiratory specimens. Microbiology laboratory protocols from 150 of 190 (79%) CF care sites were reviewed. Most described the use of selective media for Burkholderia cepacia complex (99%), Staphylococcus aureus (82%), and Haemophilus influenzae (89%) and identified the species of all gram-negative bacilli (87%). Only 52% delineated the use of agar diffusion assays for susceptibility testing of Pseudomonas aeruginosa. Standardizing laboratory practices will improve treatment, infection control, and our understanding of the changing epidemiology of CF microbiology.

Bacteria↗

Heterogeneity of treatment response to azithromycin in patients with cystic fibrosis.

RATIONALE: We recently reported a randomized, placebo-controlled trial of azithromycin in patients with cystic fibrosis (CF) that demonstrated a 6.2% improvement in the 168-d relative change in FEV1 among azithromycin participants compared with placebo participants. OBJECTIVES: In the current analyses, heterogeneity of treatment response and the association between FEV1 and the risk of pulmonary exacerbations were investigated. METHODS: The time to first pulmonary exacerbation, hospitalization rates, and antibiotic use were compared between participants categorized by their relative change in FEV1 % predicted (>or= 5 vs. < 5% improvement) at Day 168. Pulmonary function and exacerbation responses were compared in subgroups of participants characterized by long-term concomitant medications and baseline lung function. MEASUREMENTS: All available data from the 185 randomized participants in the azithromycin trial were included in these analyses. MAIN RESULTS: Compared with placebo participants, a reduced risk of pulmonary exacerbations was observed both among azithromycin participants with >or= 5% and those with < 5% relative improvement in FEV1. Similarly, decreased hospitalization rates and decreased use of oral quinolone and nonquinolone antibiotics were observed in azithromycin participants regardless of improvement in FEV1. Subgroup analyses demonstrated that overall, participants on long-term aerosolized tobramycin and/or rhDNase had worse baseline lung function, but still benefited from azithromycin, as evidenced by a lower risk of exacerbations. CONCLUSIONS: Azithromycin participants experienced benefits in exacerbation parameters regardless of FEV1 response or subgroup. These data have implications for clinical practice and the design of clinical trials.

Anti-Bacterial Agents↗

Effect of antiseptic handwashing vs alcohol sanitizer on health care-associated infections in neonatal intensive care units.

BACKGROUND: The Centers for Disease Control and Prevention, Atlanta, Ga, recommend use of waterless alcohol hand products in lieu of traditional handwashing for patient care, but there are few data demonstrating the impact of this recommendation on health care-associated infections. OBJECTIVE: To compare the effect of 2 hand hygiene regimens on infection rates and skin condition and microbial counts of nurses' hands in neonatal intensive care units. DESIGN, SETTING, AND PARTICIPANTS: Clinical trial using a crossover design in 2 neonatal intensive care units in Manhattan, NY, from March 1, 2001, to January 31, 2003, including 2932 neonatal hospital admissions (51 760 patient days) and 119 nurse participants. INTERVENTION: Two hand hygiene products were tested: a traditional antiseptic handwash and an alcohol hand sanitizer. Each product was used for 11 consecutive months in each neonatal intensive care unit in random order. RESULTS: After adjusting for study site, birth weight, surgery, and follow-up time, there were no significant differences in neonatal infections between the 2 products; odds ratios for alcohol compared with handwashing were 0.98 (95% confidence interval [CI], 0.77-1.25) for any infection, 0.99 (95% CI, 0.77-1.33) for bloodstream infections, 1.61 (95% CI, 0.57-5.54) for pneumonia, 1.78 (95% CI, 0.94-3.37) for skin and soft tissue infections, and 1.26 (95% CI, 0.42-3.76) for central nervous system infections. The skin condition of participating nurses was significantly improved during the alcohol phase (P = .02 and P = .049 for observer and self-assessments, respectively), but there were no significant differences in mean microbial counts on nurses' hands (3.21 and 3.11 log(10) colony-forming units for handwashing and alcohol, respectively; P = .38). CONCLUSIONS: Infection rates and microbial counts on nurses' hands were equivalent during handwashing and alcohol phases, and nurses' skin condition was improved using alcohol. However, assessing the impact on infection rates of a single intervention is challenging because of multiple contributory factors such as patient risk, unit design, and staff behavior. Other practices such as frequency and quality of hand hygiene are likely to be as important as product in reducing risk of cross-transmission.

Adult↗

Genetic relatedness of Staphylococcus epidermidis from infected infants and staff in the neonatal intensive care unit.

BACKGROUND: The genetic relatedness of Staphylococcus epidermidis associated with infections in infants and cultured from the hands of nurses was assessed. METHODS: From March 2001 to January 2002, infections caused by S. epidermidis were prospectively monitored. Participating nurses had hand cultures performed quarterly following hand hygiene. Pulsed-field gel electrophoresis was performed to determine genetic relatedness of strains from infants and nurses. RESULTS: During the study period, S. epidermidis caused 42 of 143 (29%) and 26 of 100 (26%) infant infections and was cultured from the clean hands of 51 of 61 (84%) and 53 of 58 (91%) nurses in neonatal intensive care unit (NICU)-1 and NICU-2, respectively. Fifty-eight clones of S. epidermidis were identified among 173 isolates typed: 38 of 173 isolates (22%) were unique clones detected in a single infant (n=10) or nurse (n=28); 42 of 173 (24%) isolates were defined as belonging to small cluster clones (n=15), ie, were detected in 2 to 4 nurses and/or infants; and 93 of 173 (54%) isolates belonged to large cluster clones (n=4), ie, detected in 7 to 64 nurses and/or infants. CONCLUSIONS: These data suggested that most S. epidermidis isolates were shared between infants and nurses. Hand hygiene alone is inadequate to prevent S. epidermidis infections, and additional strategies are needed to prevent cross transmission in NICU populations.

Carrier State↗

Tuberculosis in children.

The epidemiology of pediatric tuberculosis (TB) is shaped by risk factors such as age, race, immigration, poverty, overcrowding, and HIV/AIDS. Once infected, young children are at increased risk of TB disease and progression to extrapulmonary disease. Primary disease and its complications are more common in children than in adults, leading to differences in clinical and radiographic manifestations. Difficulties in diagnosing children stem from the low yield of mycobacteriology cultures and the subsequent reliance on clinical case definitions. Inadequately treated TB infection and TB disease in children today is the future source of disease in adults.

Child↗

Risk factors for candidemia in critically ill infants: a matched case-control study.

OBJECTIVE: To determine risk factors for late-onset candidemia among infants in the neonatal intensive care unit (NICU). STUDY DESIGN: We performed a matched case-control study from March 2001 to January 2003 in 2 level III-IV NICUs. Case subjects had candidemia diagnosed more than 48 hours after hospitalization. Control subjects (3 per case) were matched by study site, birth weight, study year, and date of enrollment. Potential risk factors included medical devices, medications, gastrointestinal (GI) pathology (congenital anomalies or necrotizing enterocolitis) and previous bacterial bloodstream infections (BSIs). RESULTS: Forty-five cases of candidemia occurred during the study period and accounted for 15% of BSIs. C. albicans caused 62% of infections (28/45); C. parapsilosis, 31% (14/45). Multivariate analysis revealed that catheter use (odds ratio [OR]=1.06 per day of use; 95% confidence interval [CI]=1.02 to 1.10), previous bacterial BSIs (OR=8.02; 95% CI=2.76 to 23.30) and GI pathology (OR=4.57; 95% CI=1.62 to 12.92) were significantly associated with candidemia. In all, 26/45 cases (58%) of candidemia occurred in infants who would not have qualified for fluconazole prophylaxis according to the Kaufman criteria. CONCLUSIONS: We confirmed previous risk factors (catheter-days) and identified novel risk factors (previous BSI and GI pathology) for candidemia in critically ill infants that could guide future targeted antifungal prophylaxis strategies.

Candidiasis↗

Epidemiology and diagnosis of hospital-acquired conjunctivitis among neonatal intensive care unit patients.

BACKGROUND: Few recent reports describe the epidemiology and risk factors for health care-associated conjunctivitis among neonatal intensive care unit (NICU) patients in developed countries. Reporting may be inaccurate in this population given that the National Nosocomial Infection Surveillance System (NNIS) definition is largely dependent on a positive culture, whereas clinical practice often consists of empiric treatment. OBJECTIVES: We describe the epidemiology of conjunctivitis among neonates in 2 level III-IV NICUs and compare the NNIS definition with our study definition: eye drainage and empiric treatment with or without a culture. METHODS: Patient demographics, clinical, device usage and conjunctivitis data collected prospectively from March 2001 through January 2003 were analyzed. RESULTS: Conjunctivitis occurred in 5% (n = 154/2935) of infants, of whom 51% (n =79) were in NICU 1 and 49% (n =75) in NICU 2. Predominant pathogens included coagulase-negative staphylococci (25%), Staphylococcus aureus (19%) and Klebsiella spp. (10%). Significant predictors of conjunctivitis included low birth weight, use of ventilator or nasal cannula continuous positive airway pressure and study year. Ophthalmologic examination was an additional predictor of infection in NICU 1. Eye examination data were unavailable for NICU 2. Only 62% of cases that met the study definition for conjunctivitis met the NNIS definition, because many infants received empiric treatment. CONCLUSIONS: Clinical conjunctivitis was associated with low birth weight and patient care factors that could lead to contamination of the eye with respiratory tract secretions. The NNIS definition failed to detect 38% of clinical infections. Consideration should be given to revising the definition of conjunctivitis for the NICU population.

Conjunctivitis, Bacterial↗

Gram-negative bacilli associated with catheter-associated and non-catheter-associated bloodstream infections and hand carriage by healthcare workers in neonatal intensive care units.

OBJECTIVE: Bloodstream infections caused by Gram-negative bacilli are a substantial cause of morbidity and mortality in infants in neonatal intensive care units. This study describes the species of Gram-negative bacilli causing bloodstream infections in two neonatal intensive care units, compares characteristics of catheter-related and non-catheter-related bloodstream infections, and compares species and antibiotic resistance patterns of these organisms with those isolated from the hands of nurses working in the same neonatal intensive care units. DESIGN: Interventional study. SETTING: Two high-risk neonatal intensive care units. PATIENTS: Neonates hospitalized for >or =24 hrs. INTERVENTIONS: Prospective surveillance for bloodstream infections was performed in two neonatal intensive care units from March 2001 to January 2003. Hand cultures were obtained quarterly from participating nurses immediately after they performed hand hygiene. MEASUREMENTS AND MAIN RESULTS: There were 298 episodes of bloodstream infections among 2,935 admissions (5.75 episodes per 1,000 patient-days); 77 of 298 (26%) episodes were caused by Gram-negative bacilli. Among these, 47 (61.0%) were catheter-related bloodstream infections (2.61 episodes per 1,000 catheter-days). Eleven and 24 Gram-negative bacilli species were isolated from neonates and nurses, respectively. The most common Gram-negative bacilli causing bloodstream infections were Klebsiella pneumoniae (38.7%), Escherichia coli (21.2%), Enterobacter cloacae (11.2%), and Serratia marcescens (11.2%). In contrast, Acinetobacter lwoffi (18.1%), K. pneumoniae (11.7%), E. cloacae (10.6%), K. oxytoca (10.6%), and Pseudomonas spp. (7.4%) were most commonly isolated from hands of nurses. E. coli, P. aeruginosa, E. cloacae, and E. aerogenes were significantly more likely to cause bloodstream infections than to be isolated from nurses' hands (all p < .001). Although 39% of bloodstream infections were non-catheter-related, there were no significant differences in types of organisms or antimicrobial resistance patterns between catheter-related bloodstream infections and non-catheter-related bloodstream infections (all p > or = .35). Resistance patterns were similar between Gram-negative bacilli isolates from neonates and nurses' hands except for a significantly higher proportion of resistance to cefotaxime and gentamicin among neonatal isolates of K. pneumoniae (p < .05). CONCLUSIONS: Gram-negative bacilli species isolated from neonatal bloodstream infections and nurses' hands varied significantly. Clean hands of providers are an unlikely source of endemic Gram-negative bacilli, suggesting that prevention strategies should focus more on control of endogenous neonatal flora or environmental sources.

Bacteremia↗

In vitro activity of doripenem (S-4661) against multidrug-resistant gram-negative bacilli isolated from patients with cystic fibrosis.

Doripenem 50% inhibitory concentrations (MIC50) and 90% inhibitory concentrations (MIC90) for multidrug-resistant strains of mucoid Pseudomonas aeruginosa (n=200 strains), nonmucoid P. aeruginosa (n=200), and Burkholderia cepacia complex (n=200) isolated from patients with cystic fibrosis were 8 and 32, 8 and 64, and 8 and 32 microg/ml, respectively. Doripenem had somewhat better activity than established antimicrobial agents.

Anti-Bacterial Agents↗