Culture-Documented Invasive Mold Infections at MD Anderson Cancer Center in Houston, Texas, Pre- and Post-Hurricane Harvey.

BACKGROUND: Extensive floodwater damage following hurricane Harvey raised concerns of excess mold infections in immunocompromised patients. This study sought to evaluate the impact of hurricane Harvey on the incidence of culture-positive invasive mold infections (cIMIs) in patients treated at MD Anderson Cancer Center (MDACC; Houston, TX). METHODS: All mold-positive culture results in the Microbiology Laboratory at MDACC in a 12-month period before and after hurricane Harvey were reviewed. cIMI cases were defined according to European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group criteria. Rates and causative agents of cIMIs pre- and post-Harvey were compared. In addition, we evaluated institution-wide trends in the use of systemically administered mold-active antifungal agents by segmented regression analysis. RESULTS: Inpatient cIMI rates per 1000 patient-days were comparable in the pre- and post-Harvey observation period (0.17 vs 0.21, P = .36). During both surveillance periods, the vast majority of cIMI cases were due to Aspergillus spp., Fusarium spp., or Mucorales. No emergence of unusual mold infections was seen, and the relative frequencies of mold genera recovered from cultures at the MDACC Microbiology Laboratory remained largely unaltered. The overall use of posaconazole was significantly higher in the post-Harvey period and the use of both voriconazole and liposomal amphotericin B began to increase significantly immediately after Harvey. CONCLUSIONS: Our monocentric study employing stringent culture-based definitions of mold infections found no excess cases of IMIs in MDACC's immunosuppressed patient population in the aftermath of a major flooding event. Increased use of some mold-active antifungals in the aftermath of hurricane Harvey was observed institutionally.

What Is the Real Rate of Surgical Site Infection?

PURPOSE: Surgical site infections (SSIs) are associated with patient morbidity and increased health care costs. Although several national organizations including the University HealthSystem Consortium (UHC), the National Surgical Quality Improvement Program (NSQIP), and the National Healthcare Safety Network (NHSN) monitor SSI, there is no standard reporting methodology. METHODS: We queried the UHC, NSQIP, and NHSN databases from July 2012 to June 2014 for SSI after gynecologic surgery at our institution. Each organization uses different definitions and inclusion and exclusion criteria for SSI. The rate of SSI was also obtained from chart review from April 1 to June 30, 2014. SSI was classified as superficial, deep, or organ space infection. The rates reported by the agencies were compared with the rates obtained by chart review using Fisher's exact test. RESULTS: Overall SSI rates for the databases were as follows: UHC, 1.5%; NSQIP, 8.8%; and NHSN, 2.8% (P < .001). The individual databases had wide variation in the rate of deep infection (UHC, 0.7%; NSQIP, 4.7%; NHSN, 1.3%; P < .001) and organ space infection (UHC, 0.4%; NSQIP, 4.4%; NHSN, 1.4%; P < .001). In agreement with the variation in reporting methodology, only 19 cases (24.4%) were included in more than one database and only one case was included in all three databases (1.3%). CONCLUSION: There is discordance among national reporting agencies tracking SSI. Adopting standardized metrics across agencies could improve consistency and accuracy in assessing SSI rates.

Association of increased influenza vaccination in health care workers with a reduction in nosocomial influenza infections in cancer patients.

BACKGROUND: Vaccination of health care workers (HCWs) remains a key strategy to reduce the burden of influenza infections in cancer patients. METHODS: In this 8-year study, we evaluated the effect of a multifaceted approach, including a mandatory influenza vaccination program, on HCW vaccination rates and its effect on nosocomial influenza infections in cancer patients. RESULTS: The influenza vaccination rate of all employees significantly increased from 56% (8,762/15,693) in 2006-2007 to 94% (17,927/19,114) in 2013-2014 (P < .0001). The 2009 mandatory participation program increased HCW vaccination rates in the targeted groups (P < .0001), and the addition of an institutional policy in 2012 requiring influenza vaccination or surgical mask use with each patient contact further increased vaccination rates by 10%-18% for all groups in 1 year. The proportion of nosocomial influenza infections significantly decreased (P = .045) during the study period and was significantly associated with increased HCW vaccination rates in the nursing staff (P = .043) and in personnel working in high-risk areas (P = .0497). CONCLUSIONS: Multifaceted influenza vaccination programs supported by institutional policy effectively increased HCW vaccination rates. Increased HCW vaccination rates were associated with a reduction in the proportion of nosocomial influenza infections in immunocompromised cancer patients.

Healthcare-associated outbreaks due to Mucorales and other uncommon fungi.

BACKGROUND: Healthcare-associated outbreaks of fungal infections, especially with uncommon and emerging fungi, have become more frequent in the past decade. MATERIALS AND METHOD: Here, we reviewed the history and definition of healthcare-associated outbreaks of uncommon fungal infections and discussed the principles of investigating, containing and treatment of these outbreaks. RESULTS: In case of these uncommon diseases, occurrence of two or more cases in a short period is considered as an outbreak. Contaminated medical devices and hospital environment are the major sources of these outbreaks. Care must be taken to differentiate a real infection from colonization or contamination. Defining and identifying cases, describing epidemiologic feature of cases, finding and controlling the source of the outbreak, treating patients, and managing asymptomatic exposed patients are main steps for outbreak elimination. These fungal outbreaks are not only difficult to detect but also hard to treat. Early initiation of appropriate antifungal therapy is strongly associated with improved outcomes in infected patients. Choice of antifungal drugs should be made based on spectrum, pharmacodynamic and pharmacokinetic characteristics and adverse effects of available drugs. Combination antifungal therapy and surgical intervention may be also helpful in selected cases. CONCLUSIONS: A multidisciplinary approach and close collaboration between all key partners are necessary for successful control of fungal outbreaks.

Timing of infectious complications following breast-conserving therapy with catheter-based accelerated partial breast irradiation.

BACKGROUND: Accelerated partial breast irradiation (APBI) has been used as an alternative to whole-breast irradiation as part of breast-conserving therapy. Indications and outcomes are topics of ongoing investigation. Previous publications have focused on early postoperative infections and reported low rates of delayed infection. We investigated the pattern of infection after catheter-based APBI at our institution. METHODS: Patients who underwent single-entry catheter-based APBI were identified from an institutional prospective registry including data regarding comorbidities and outcomes. Time of infection was calculated from the date of definitive catheter insertion and classified as early (≤30 days) or delayed. RESULTS: A total of 91 breast cancer patients were treated with APBI and enrolled in the registry from 2009 to 2011. The median follow-up was 484 days. Breast infection occurred in 13 (14.3 %), with 3 (3.3 %) occurring within 30 days of catheter placement and 10 (11.0 %) in a delayed fashion. Four patients required hospital admission, five underwent percutaneous aspiration, and one underwent incision and drainage. Eight were treated as outpatients with oral antibiotics alone. CONCLUSIONS: Consistent with other reports, we found an overall infection rate of 14.3 % with single-entry catheter-based APBI. There were substantially fewer infections in the early postoperative period than reported elsewhere, but there were more delayed infections. The intensive follow-up in our study likely identified late infections that may not have otherwise been recognized. Vigilance for infectious complications must continue beyond the immediate treatment period in patients undergoing catheter-based APBI. These infections can range in severity but typically can be managed in an outpatient setting.

Perioperative antimicrobial prophylaxis for intra-abdominal surgery in patients with cancer: a retrospective study comparing ertapenem and nonertapenem antibiotics.

BACKGROUND: To evaluate the role of ertapenem versus other standard antibiotic prophylaxis in patients with cancer undergoing intra-abdominal surgery. METHODS: Our study was a retrospective cohort study consisting 615 patients who underwent intra-abdominal surgery at our institution between January 2007 and December 2010. The groups were divided among patients who received ertapenem as perioperative prophylaxis (ertapenem group) and patients who received other antibiotics (nonertapenem group). Groups were similar with respect to age, gender, and type of surgery. RESULTS: A total of 315 patients underwent colorectal and 300 noncolorectal surgeries. In a multivariate logistic regression model, the main factors associated with risk of surgical site infections (SSI) were as follows: antibiotics within 3 months of surgery (odds ratio [OR] 1.2, 95% confidence interval [CI] 1.04-1.54; p = 0.05), prior hospitalization within 1 year (OR 1.21, 95% CI 1.02-1.43; p = 0.05), diabetes mellitus (OR 2.1, 95% CI 1.7-3.4; p = 0.04), and perioperative prophylaxis other than ertapenem (OR 1.7, 95% CI 1.2-2.3; p = 0.04). Notably, patients who underwent colorectal surgery and received ertapenem had a lower rate of SSI (4% ertapenem vs. 13% nonertapenem, p = 0.01), whereas the frequency of infections was not different in patients who underwent other intra-abdominal surgery whether they received ertapenem or not. CONCLUSIONS: The use of ertapenem for perioperative prophylaxis in patients with colorectal surgery was associated with lower rates of SSI, while there was no difference in rates of infection in other intra-abdominal surgery.

Characteristics and outcomes of methicillin-resistant Staphylococcus aureus surgical-site infections in patients with cancer: a case-control study.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infections remain a significant cause of morbidity and mortality. We experienced an increased incidence of MRSA surgical-site infections (MRSA SSIs) at our institution. However, to our knowledge, no studies have evaluated the risk factors and outcomes of MRSA SSIs in cancer patients. METHODS: We conducted a case-control study and identified all patients who had developed MRSA SSIs at our institution from July 1, 2002 to July 30, 2003, and all patients who had undergone surgery by the same surgical team during the same time period but who had not developed MRSA SSIs. Cases and controls were age-matched at 1:2 ratio. RESULTS: The study included 29 cases and 58 controls. Mean interval between surgery and MRSA SSI onset was 17.8 days (range 3-75 days). Cases were more likely than controls to have progressive cancer (72 versus 38%), have received antibiotics (mainly quinolones) within 24 h of surgery (17 versus 2%), have had ongoing infection (10 versus 0%), and have had longer hospital and intensive care unit stays (11.0 versus 7.8 days and 3.4 versus 1.5 days) (all P < 0.05). In a multivariate logistic regression analysis, significant predictors of MRSA SSI in cancer patients were antibiotics use <24 h of surgery and progressive cancer. No surgical factors (i.e., procedure time or timing of perioperative antibiotics) were associated with increased risk of MRSA SSI. CONCLUSIONS: Several clinical and postoperative factors were associated with increased risk of MRSA SSI in cancer patients, but antibiotic use before surgery (especially quinolones) and progressive cancer were the only independent predictors.

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.

The role of molecular methods in the prevention of nosocomial methicillin-resistant Staphylococcus aureus clusters in cancer patients.

In 2002, an increased incidence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) in our institution triggered a conventional investigation that failed to identify a common source. Molecular typing of the 70 nosocomial MRSA isolates obtained identified a predominant health care-associated clone A in the first trimester. Aggressive infection control measures led to a significant decrease in the number of isolates per 10,000 hospital days between the first trimester and the last 2 trimesters of 2003 (6.4 vs 3.8; P = .04). This was attributed to a decrease in clone A: SCCmec II, USA100, PVL gene-negative (2.3 per 10.000 patient-days vs 0.1 per 10,000 patient-days; P = .004). However, in 2003, 23% of the nosocomial isolates were SCCmec IV, USA300, PVL gene-positive. At that time, molecular methods allowed the detection and prevention of a nosocomial MRSA outbreak caused by a health care-associated clone; however, the community strains (SCCmec IV) have become a frequent cause of nosocomial infection in our institution.

Chest tube-related empyema due to methicillin-resistant Staphylococcus aureus: could the chest tube be coated with antiseptics?

We reviewed the epidemiology, clinical manifestations, and outcomes of 3 cases of chest tube-related empyema due to methicillin-resistant Staphylococcus aureus (MRSA). Antiseptic-impregnated chest tubes were inserted in cultures containing MRSA isolates from these 3 patients, and zone of inhibition were measured. Chest tube-related MRSA empyema might complicate tube thoracostomy, and coating the chest tube with antiseptic agents could prevent this complication.

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

BACKGROUND: 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. METHODS: Patients with cancer who were infected with multidrug-resistant P. aeruginosa with polyclonal DNA restriction patterns were used as the case group. Two control groups were used: one group of cancer patients who were infected with multidrug-susceptible P. aeruginosa and another group of cancer patients who had the same underlying disease and the same intensive care unit exposure as patients in the case group but who were not infected or colonized by P. aeruginosa. RESULTS: Risk factors that were associated significantly with multidrug-resistant P. aeruginosa infection were the use of carbapenem for > or = 7 days, a history of P. aeruginosa infection during the preceding year, and a history of chronic obstructive pulmonary disease (P < 0.01). CONCLUSIONS: Carbapenems may need to be used more judiciously as first-line empirical therapy for cancer patients with prior pseudomonal infection or chronic obstructive pulmonary disease who require hospitalization, and alternative, antipseudomonal antibiotic regimens may need to be considered, especially in this patient population.

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.

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.