Cheryl Perego

Zygomycosis in a Tertiary-Care Cancer Center in the Era of Aspergillus-Active Antifungal Therapy: A Case-Control Observational Study of 27 Recent Cases

BACKGROUND Anecdotal evidence suggests a rise in zygomycosis in association with voriconazole (VRC) use in immunosuppressed patients. METHODS We performed prospective surveillance of patients with zygomycosis (group A; n = 27) and compared them with contemporaneous patients with invasive aspergillosis (group B; n = 54) and with matched contemporaneous high-risk patients without fungal infection (group C; n = 54). We also performed molecular typing and in vitro susceptibility testing of Zygomycetes isolates. RESULTS Nearly all patients with zygomycosis either had leukemia (n = 14) or were allogeneic bone marrow transplant recipients (n = 13). The Zygomycetes isolates (74% of which were of the genus Rhizopus) had different molecular fingerprinting profiles, and all were VRC resistant. In multivariate analysis of groups A and C, VRC prophylaxis (odds ratio [OR], 10.37 [95% confidence interval [CI]], 2.76-38.97]; P = .001), diabetes (OR, 8.39 [95% CI, 2.04-34.35]; P = .003), and malnutrition (OR, 3.70 [95% CI, 1.03-13.27]; P = .045) were found to be independent risk factors for zygomycosis. Between patients with zygomycosis (after excluding 6 patients with mixed mold infections) and patients with aspergillosis, VRC prophylaxis (OR, 20.30 [95% CI, 3.85-108.15]; P = .0001) and sinusitis (OR, 76.72 [95% CI, 6.48-908.15]; P = .001) were the only factors that favored the diagnosis of zygomycosis. CONCLUSIONS Zygomycosis should be considered in immunosuppressed patients who develop sinusitis while receiving VRC prophylaxis, especially those with diabetes and malnutrition.

Aspergillus terreus: an emerging amphotericin B-resistant opportunistic mold in patients with hematologic malignancies.

Invasive aspergillosis (IA) has emerged as a common cause of morbidity and mortality among immunocompromised patients. At The University of Texas M. D. Anderson Cancer Center (Houston, TX), Aspergillus terreus is second to A. fumigatus as the most common cause of IA. In the current study, the authors compared the risk factors and outcomes associated with IA caused by A. terreus and IA caused by A. fumigatus.

Risk factors for infections with multidrug‐resistant Pseudomonas aeruginosa in patients with cancer

Pseudomonas aeruginosa is responsible for a wide range of infections. In immunocompromised patients with cancer, the emergence of multidrug resistant P. aeruginosa may have grave consequences.

Geoclimatic Influences on Invasive Aspergillosis after Hematopoietic Stem Cell Transplantation

BACKGROUND Aspergillus species are ubiquitous. We hypothesized that climatic variables that affect airborne mold counts affect the incidence of invasive aspergillosis (IA). METHODS Patients who received hematopoietic stem cell transplants (HSCTs) in geographically and climatically diverse regions (Seattle, WA, and Houston, TX) were examined. Cumulative incidence function, Kaplan-Meier analysis, and Cox proportional hazards regression were performed to examine the association between IA and season. Poisson regression analysis was performed to evaluate the seasonal patterns in IA rates and association with spore counts and climate. RESULTS In Seattle, the 3-month incidence of IA was 4.6% (5.7% in allograft recipients and 0.8% in autograft recipients). During the 10-year study period, there was a decrease in the incidence of IA among allogeneic HSCT recipients, corresponding to decreased risks during the nonsummer months; receipt of HSCTs during the summer months was associated with an increased hazard for IA (hazard ratio, 1.87; 95% confidence interval, 1.25-2.81) after adjustment for other known risks. The person-month IA rate in Seattle was positively associated with environmental spore counts, which increased with high temperature and low precipitation. No seasonal effect on IA was observed in Houston, where total spore counts were lower and not variable by climate. CONCLUSIONS Climatic variables differentially affect airborne spore counts and IA risk in geographically disparate centers.

Clinical experience with minocycline and rifampin-impregnated central venous catheters in bone marrow transplantation recipients: efficacy and low risk of developing staphylococcal resistance.

In this retrospective evaluation of the 4-year clinical use of minocycline and rifampin-impregnated catheters in bone marrow transplantation (BMT) patients, we report low risk of development of staphylococcal resistance to the antibiotics coating the catheters and efficacy in preventing primary staphylococcal bloodstream infections.

Impact of Surveillance for Vancomycin-Resistant Enterococci on Controlling a Bloodstream Outbreak among Patients with Hematologic Malignancy

OBJECTIVE To determine the impact of stool surveillance cultures of critically ill patients on controlling vancomycin-resistant enterococci (VRE) outbreak bacteremia. DESIGN Stool surveillance cultures were performed on patients who had hematologic malignancy or were critically ill at the time of hospital admission to identify those colonized with VRE. Hence, contact isolation was initiated. SETTING A tertiary-care cancer center with a high prevalence of VRE. PARTICIPANTS All patients with hematologic malignancy who were admitted to the hospital as well as all of those admitted to the intensive care unit were eligible. RESULTS Active stool surveillance cultures performed between 1997 and 2001 decreased the incidence density of VRE bacteremias eightfold while vancomycin use remained constant. In fiscal year (FY) 1997 and FY 1998, there were five and three VRE outbreak bacteremias, respectively. The outbreak clones were responsible for infection in 69% of those patients with VRE bacteremia. However, the stool surveillance program resulted in the complete control of VRE bacteremia by FY 1999 until the end of the study. CONCLUSION Despite the steady use of vancomycin, the active surveillance program among high-risk patients with hematologic malignancy and those who were critically ill resulted in the complete control of VRE outbreak bacteremia at our institution.

Detection and control of a nosocomial respiratory syncytial virus outbreak in a stem cell transplantation unit: the role of palivizumab.

Respiratory syncytial virus (RSV) is a common community-acquired virus that causes upper and lower respiratory tract infections in children, hematologic malignancy patients, and hematopoietic stem cell transplant (HSCT) recipients. Nosocomial transmission of RSV in immunocompromised patients can significantly affect morbidity, mortality, and duration of hospitalization. Stringent infection control measurements are needed to control further hospital transmission. Prophylactic palivizumab was found to result in a significant reduction in hospitalization rates in high-risk children. In this article, we report a nosocomial outbreak of RSV in an adult HSCT unit (4 pods) from January 16 to February 4, 2004, including the infection control interventions used and the prophylactic administration of palivizumab in high-risk patients. Active surveillance identified 5 cases, a substantial increase from previous seasons (2 or 3 cases per season). All infected patients were isolated to 1 nursing pod and placed on contact isolation. All patients on the HSCT unit underwent rapid RSV antigen screening using nasal washes; this was repeated 1 week later, and 1 additional RSV case was identified. Patients identified to be at increased risk for RSV infection received prophylactic palivizumab. Routine screenings of the staff and visitors were undertaken. All patient and visitor areas were thoroughly cleaned with bleach. We educated health care workers about RSV transmission, highlighting proper hand hygiene and contact precautions. Four of 6 patients with RSV infection developed RSV pneumonia, and 2 of these patients died. Staff and visitors with upper respiratory symptoms were screened, and all were negative for RSV. Prophylactic palivizumab was administered in 16 patients who tested negative for RSV, but were considered to be at increased risk for RSV infection. None of these patients developed RSV infections. An RSV outbreak was controlled using prompt preventive measures, including cohorting patients, with a dedicated health care staff; contact isolation of patients; strict adherence to hand hygiene; and screening of visitors, family members, and health care staff for upper respiratory infection symptoms. Immunoprophylaxis with palivizumab, administered to high-risk patients, complemented strict infection control intervention. Thus, the role of palivizumab in the control of RSV hospital outbreaks merits further investigation.

The role of interventional molecular epidemiology in controlling clonal clusters of multidrug resistant Pseudomonas aeruginosa in critically ill cancer patients.

BACKGROUND Pseudomonas aeruginosa is one of the leading causes of hospital-acquired infections in intensive care units (ICUs). The objective was to evaluate the impact of molecular identification of clonal multidrug-resistant (MDR) P aeruginosa strains and the implementation of infection control measures. METHODS One hundred seventy-seven strains from ICU patients infected or colonized with MDR P aeruginosa from May 2001 to April 2006 were collected. In vitro susceptibility to 16 antibiotics was done. Pulsed-field gel electrophoresis was performed to identify clonal strains. Nosocomial outbreak was defined as the presence of > or =3 MDR P aeruginosa over < or =3 consecutive months. RESULTS During the 5 years of the study, 25 infected and 14 colonized patients with a clonal strain of MDR P aeruginosa were distributed among 5 episodic clusters. These strains were only susceptible to ceftazidime and colistin. Molecular biology identification, diligent monitoring, and multidisciplinary infection control interventions were implemented to suppress this clonal strain after each cluster. Even more, after the last outbreak (June-August 2005), the infection control measures were able to reduce the MDR P aeruginosa to zero during the last 8 months of this study. CONCLUSION Interventional molecular epidemiology combined with early identification, monitoring, and implementation of multidisciplinary infection control measures can control temporarily the transmission of MDR P aeruginosa infection in ICUs.

Unit-Based Staff Hand Hygiene (HH) Monitors To Improve Compliance in a Comprehensive Cancer Center

ISSUE: Both the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) patient safety goal and the Centers for Disease Control and Preventions (CDC) guidelines recommend monitoring of hand hygiene adherence and providing feedback to patient care staff. In order to advance patient safety and HH compliance, a three-pronged approach was implemented to enhance HH education, observation and measurement of HH compliance. PROJECT: Three components were implemented to improve compliance with HH practices: Education Component (Phase I) Development and implementation of a mandatory computer-based learning module on hand hygiene for all patient care staff that included HHs “Top Ten List” based on CDCs Guideline for Hand Hygiene in Health-Care Settings, 2002 Focused and targeted educational program for fellows, residents and mid-level providers including staff in invasive procedural areas Special educational HH program in Spanish for spanish-speaking staff Training of unit-based HH observers (100) using the Train-the-Trainer model Focus on HH compliance during Patient Safety Week Campaign in March 2005 Evaluation Component (Phase II) Three HH observational periods for assessment of HH compliance by trained HH monitors and infection control practitioners in all patient care areas Monthly self-assessment in patient care area units and diagnostic areas Communication and Feedback of Results Component (Phase III) Communication to staff, managers and administration regarding HH violations and compliance rates Prompt follow-up with re-education in patient care areas where HH violations rates were lower than expected. RESULTS: In Phase I, 100% of patient care staff complied with HH computer-based training. A total of 100 unit-based HH observers were trained using the Train-the-Trainer approach with education on HH basics, use of HH tool and feedback to colleagues and peers. In Phases II and III, observational periods with assessment of HH compliance were implemented by the trained HH observer of each clinical area. Data from observation periods, demonstrated an incremental improvement in HH practices with an initial baseline of 79% and an average of 91% in subsequent periods. LESSONS LEARNED: A coordinated systems approach that includes patient care staff, physicians, committees and administration is essential when initiating a process change. Providing education and feedback to staff and physicians will improve compliance. Identification of areas where additional education and feedback on HH is required and will also improve compliance.