Investigation and control of aspergillosis and other filamentous fungal infections in solid organ transplant recipients

Filamentous fungal infections are associated with high morbidity and mortality in solid organ transplant patients, and prevention is warranted whenever possible. An increase in invasive aspergillosis was detected among solid organ transplant recipients in our institution during 1991–92. Rates of Aspergillus infection (18.2%) and infection or colonization (42%) were particularly high among lung transplant recipients. Epidemiologic investigation revealed cases to be both nosocomial and community‐acquired, and preventative efforts were directed at both sources. Environmental controls were implemented in the hospital, and itraconazole prophylaxis was given in the early period after lung transplantation. The rate of Aspergillus infection in solid organ transplant recipients decreased from 9.4% to 1.5%, and mortality associated with this disease decreased from 8.2% to 1.8%. The rate of Aspergillus infection or colonization among lung transplant recipients decreased from 42% to 22.5%; nosocomial Aspergillus infection decreased from 9% to 3.2%. Cases of aspergillosis in lung transplant recipients were more likely to be early infections in the pre‐intervention period. Early mortality in lung transplant recipients decreased from 15% to 3.2%. Two cases of dematiaceous fungal infection were detected, and no further cases occurred after environmental controls. The use of environmental measures that resulted in a decrease in airborne fungal spores, as well as antifungal prophylaxis, was associated with a decrease in aspergillosis and associated mortality in these patients. Ongoing surveillance and continuing intervention is needed for prevention of infection in high‐risk solid organ transplant patients.     

Filtering hospital air decreases Aspergillus spore counts.

We performed counts of airborne spores in a hospital with filtered air where a decrease in nosocomial infection with Aspergillus organisms had been documented. For comparison, similar studies were performed at a nearby general hospital in a ward with open windows. The total spore count inside the hospital with filtered air was significantly less than inside the ward with open windows. The total count of Aspergillus organisms in the filtered air was significantly less than that in the room with open windows. We conclude that the decrease in nosocomial infections with Aspergillus organisms in the hospital with filtered air is probably associated with fewer airborne spores.     

Endemic and epidemic aspergillosis associated with in-hospital replication of Aspergillus organisms

When a new hospital opened in 1983, environmental culturing for Aspergillus organisms and surveillance for nosocomial aspergillosis cases were begun to characterize the relationship between environmental contamination and infection. Monthly air sampling demonstrated increasing concentrations of Aspergillus flavus and Aspergillus fumigatus to mean levels greater than 1 cfu/m3 during 1986-1987, accompanied by a progressive increase in incidence of aspergillosis to 1.2% in immunocompromised patients. This prompted an inspection that revealed heavy growth of Aspergillus organisms on air filters. Subsequent inspections of hospital wards showed small foci of A. flavus growth on other materials. Removal of the contaminated filters and improved environmental maintenance were associated with reduction in A. flavus and A. fumigatus to 0.01 cfu/m3 and a fourfold decline in aspergillosis incidence during the next 2 years. These findings, together with laboratory studies that showed aspergilli could proliferate on common hospital materials when moistened, indicate a need for careful environmental maintenance.     

APACHEⅢ评分与老年冠状动脉移植术后IABP辅助治疗的医院感染

目的分析冠状动脉移植术后主动脉内球囊反搏辅助的老年患者的医院感染情况与APACHEⅢ评分的相关性。方法回顾性收集、分析我院2006年4月至2009年2月冠状动脉移植术后IABP辅助治疗的老年（≥65岁）患者的医院感染资料,并进行APACHEⅢ评分系统评估。结果 111例患者,年龄69.9±3.8岁,男77例,女34例。医院感染29例,感染率26.1%。患者平均APACHEⅢ评分为60.8±14.0,高分组患者的医院感染率和住院死亡率均高于低分组。结论医院感染是老年冠状动脉移植术后IABP辅助患者的死亡危险因素之一,APACHEⅢ评分系统可作为预测医院感染发生的方法之一。     

Intracerebral hemorrhage due to nosocomial aspergillosis following neurosurgery

A unique case of nosocomial aspergillosis following neurosurgery in a 10 year old girl was documented. She presented with intracerebral hemorrhage after three weeks of operation for evacuation of craniopharyngioma. To our knowledge, this is the first reported case of intracerebral hemorrhage due to nosocomial aspergillosis following neurosurgery.     

Prospective surveillance applying the national nosocomial infection surveillance methods in a Brazilian pediatric public hospital

BACKGROUND: A hospital-wide, traditional prospective surveillance for nosocomial infections was commenced in 1992 in Centro Geral de Pediatria in Minas Gerais, Brazil, to describe the epidemiology of nosocomial infection in this pediatric hospital and to implement cross-infection prevention and control policies. METHODS: We performed a prospective cohort nosocomial infection surveillance of all patients receiving acute care according to the hospital-wide and intensive care unit components of the National Nosocomial Infections Surveillance System from January 1993 to December 1997 (14,892 discharges; 131,764 patient-days). The Centers for Disease Control and Prevention (Atlanta) 1988-definitions and the Brazilian Ministry of Health-Legislation 930 (1992) were used. RESULTS: The average overall nosocomial infection rate per 1000 patient-days was 8.9 in units 2 and 3 and 16.4 in the pediatric intensive care unit. Over time, the overall hospital infection rate decreased from 16.6 nosocomial infections per 1000 patient-days in 1993 to 7.0 in 1997 (P <.05). We believe this can be attributed to interventions and data reporting during the period. The five most frequent sites of infections were eye-ear-nose-throat (38%), skin (22%), pneumonia (12%), soft tissue (5%) and laboratory-confirmed bloodstream infection (4%). In the pediatric intensive care unit, the most frequent nosocomial infection sites were pneumonia related to mechanical ventilators (22%), with rates ranging from 0 to 42 per 1000 ventilator-days; and sepsis related to central lines (11%), with rates ranging from 0 to 32 per 1000 central line-days. CONCLUSIONS: Describing the epidemiology of nosocomial infections in this hospital enabled us to establish infection occurrence, distribution, and expected incidence, as well as to recognize trends and keep track of possible outbreaks. The knowledge acquired through this surveillance allowed us to target more specific and continuous quality improvement projects, to upgrade health care quality in pediatric public hospitals in Brazil, and to implement preventive strategies. Methods from the National Nosocomial Infections Surveillance System can be successfully applied in pediatric public hospitals in Brazil.     

儿科住院病人医院感染危险因素的病例对照调查

目的探讨儿科病房医院感染发生率及其危险因素。方法选择某医院2003～2005年1352例患儿为研究对象,以其中医院感染者为病例组,非医院感染者为对照组进行病例对照研究。病例组和对照组按1︰1配比设立对照,以条件logistic法筛选出儿科病房医院感染的危险因素。结果儿科病房医院感染率为7.7%。单因素和多因素分析发现,住院时间、不合理使用抗生素、侵袭性操作、重症监护等是医院感染的危险因素。结论合理使用抗生素、缩短住院时间、减少侵袭性操作将有利于预防和控制儿科医院感染。     

Fever and cavitary infiltrate in a renal transplant recipient

Aspergillus infection is a rare but devastating complication following organ transplantation with high mortality rate. Aspergillus fumigatus is the most common cause of invasive aspergillosis. This fungus is present in the environment worldwide. Aspergillus infection is mainly acquired by inhalation of spores and several nosocomial infections in transplant recipient have been associated with construction work at hospitals. Risk factors for invasive aspergillosis include administration of steroid boluses, history of cytomegalovirus infection, neutropenia and prolonged antibiotic use after transplantation. Successful treatment depends on three factors: early diagnosis, aggressive antifungal therapy and decrease or removal of immunosuppression. Amphotericin deoxycholate has been the standard treatment for many years but lipid preparations for amphotericin are now used due to their significantly fewer adverse effects. A number of new antifungal drugs are now being developed including new azoles such as voriconazol and echinocandin. Invasive aspergillosis has a high mortality rate more than 95% when cerebral dissemination is demonstrated. We report the case of a 47 years old woman who received a cadaveric renal graft and developed pulmonary aspergillosis with fulminant cerebral dissemination two months later. The diagnosis of pulmonary aspergillosis was by culture isolation obtained from bronchioalveolar lavage. Removal of immunosuppresive agents and liposomal amphotericin B therapy were started shortly after admission. Brain CT scan performed on the 12th day showed cerebral dissemination. The recipient died two days later. Our patient had several risk factors such as the administration of steroid boluses and cytomegalovirus infection. Invasive aspergillosis must be always included in the differential diagnosis of fever and pulmonary disease in the renal transplant recipient.     

综合重症监护病房老年患者医院感染现状及危险因素分析

目的 了解综合重症监护病房(intensive care unit,ICU)老年患者医院感染现状,探讨老年患者发生医院感染的危险因素.方法 回顾性调查2015年1月-2019年6月期间在上海市某三甲医院综合ICU内年龄≥65岁的老年住院患者发生医院感染的情况,分析主要感染类型和检出病原菌种类,采用病例对照研究方法,比较...     

Methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii: An unexpected difference in epidemiologic behavior

Background: The Dutch guideline on hospital policy for the prevention of nosocomial spread of methicillin-resistant Staphylococcus aureus (MRSA) states that patients transferred from hospitals abroad must be placed in strict isolation immediately on admission to a hospital in the Netherlands. Three patients colonized with both MRSA and a multiresistant Acinetobacter were transferred from hospitals in Mediterranean countries to 3 different hospitals in the Netherlands. Despite isolation precautions, Acinetobacter spread in 2 of the 3 hospitals, whereas nosocomial spread of MRSA did not occur. Methods: For outbreak analysis, the Acinetobacter isolates, identified as Acinetobacter baumannii by the use of amplified ribosomal DNA restriction analysis, were comparatively typed by 4 methods. Comparison of isolation measures in the hospitals was performed retrospectively. Results: In the 2 hospitals in which nosocomial spread of Acinetobacter occurred, most of the epidemiologically related isolates were indistinguishable from the index strains. In these 2 hospitals, isolation measures were in concordance with those recommended for the prevention of contact transmission. The precautions of the hospital in which no outbreak occurred included the prevention of airborne transmission. Conclusions: Precautions recommended for multiresistant gram-negative organisms are insufficient for the prevention of nosocomial spread of multiresistant Acinetobacter . The airborne mode of spread of acinetobacters should be taken into account, and guidelines should be revised accordingly. (AJIC Am J Infect Control 1998;26:544-51)     

Invasive pulmonary aspergillosis in neutropenic patients during hospital construction: before and after chemoprophylaxis and institution of HEPA filters

Between September 1993 and December 1993, during extensive hospital construction and indoor renovation, a nosocomial outbreak of invasive pulmonary aspergillosis occurred in acute leukemia patients treated in a regular ward that has only natural ventilation. The observed infection rate was 50%. Chemoprophylaxis with intravenous continuous low-dose amphotericin B was then instituted as a preventive measure. During the next 18 months invasive pulmonary aspergillosis developed in 43% of acute leukemia patients. After that period a new hematology ward was opened with an air filtration system through high-efficiency particulate air filtration (HEPA) filters, and a bone marrow transplantation program was started on the hematology service. During the following three years, none of the acute leukemia or bone marrow transplantation patients who were hospitalized exclusively in the hematology ward developed invasive pulmonary aspergillosis, although 29% of acute leukemia patients who were housed in a regular ward, because of shortage of space in the new facility, still contracted invasive pulmonary aspergillosis. Overall, 31 patients were diagnosed with invasive pulmonary aspergillosis during almost five years: 74% of patients recovered from invasive pulmonary aspergillosis, and 42% are long-term survivors; 26% of patients died of resistant leukemia with aspergillosis, but no one died of invasive pulmonary aspergillosis alone. In conclusion, during an on-going construction period, an extremely high incidence rate of invasive pulmonary aspergillosis in acute leukemia patients undergoing intensive chemotherapy was observed. Institution of low-dose intravenous amphotericin B prophylaxis marginally reduced the incidence rate of invasive pulmonary aspergillosis. Keeping patients in a special ward with air filtration through a HEPA system eliminated invasive pulmonary aspergillosis completely. Among patients who developed invasive pulmonary aspergillosis, early diagnosis and treatment are probably the explanation for the favorable outcome.     

Nosocomial infection control: an overview

Nosocomial infections are one of the most important public health problems in the world today. Although a great deal of attention is being directed toward the control and prevention of these infections, old problems continue to occur and new problems are constantly arising. The approximately 5% rate of nosocomial infections among patients admitted to acute-care hospitals has a significant impact on patients morbidity and morality and on the financial concerns of the patient, hospital, and community. An effective, efficient, and sensitive surveillance program developed to meet the needs of the individual hospital is absolutely necessary to obtain data on nosocomial infections from which controls and prevention programs can be developed. At the same time, lessons can be learned from the experience of other hospitals. The nosocomial infection control and prevention program must be under the general direction of a representative, interested, effective infection control committee. One area of importance under the committee's responsibility is that of an appropriate isolation program practiced by all persons within the hospital.     

Risk factors for nosocomial infection.

Studies of nosocomial infection are difficult to evaluate because of differences in the relative susceptibility of patients to the acquisition of such infections, the use of different methods of surveillance, and the frequent failure to distinguish between measurements of incidence and of prevalence. A standardized approach to these variables has been tested at a large municipal hospital. The systematic identification of potential risk factors for nosocomial infection allows the evaluation of the individual components of risk, valid epidemiologic comparisons between hospital populations, and a more accurate estimate of the potential cost-effectiveness of activities for the control of infection. The data indicate that it is feasible to calculate the relative risk of nosocomial infection for each patient, using basic criteria obtainable at the bedside, supplemented with other generally available information. The risk of infection must be calculated per day rather than per admission to separate the effect of long hospital stay from the effect of high daily risk. Certain underlying diseases, procedures, hospital services, and categories of age, sex, race, and urgency of admission were all found to be significant risk factors for nosocomial infection.     

Differential risks of nosocomial infection

Our ability to interpret apparent differences in findings among surveys of nosocomial infection is limited by differences in the methods used, and differences among the study populations themselves. Methodologic areas in which there are substantial differences include definitions of rates of infection, criteria for infection and methods of case-finding. The studies themselves differ with respect to the characteristics of hospital populations, their underlying diseases, clinical procedures, patterns of lengths of hospital stay and efforts at prevention of infection. There are three separate concerns for constructing and interpreting comparisons: the choice of comparison or reference subjects, the control of confounding variables and the adjustment for variations in hospital stay. In order for studies to be credible, they must be accompanied by convincing evidence that the confounding effects of variables extraneous to the study have been identified and appropriately controlled in the analysis. It has been found that the day-specific incidence of nosocomial infection rises from near zero on the first hospital day to maximal during the fourth through the seventh weeks of hospital stay. Thus, the risk of nosocomial infection for a specific patient also depends on the hospital day. It may be possible to make better use of limited infection control resources by concentrating efforts to prevent infections on the patients who are at greatest risk, during the time when the dayspecific incidence is highest.     

Pediatric mortality due to nosocomial infection: a critical approach.

Nosocomial infection is a frequent event with potentially lethal consequences. We reviewed the literature on the predictive factors for mortality related to nosocomial infection in pediatric medicine. Electronic searches in English, Spanish and Portuguese of the PubMed/MEDLINE, LILACS and Cochrane Collaboration Databases was performed, focusing on studies that had been published from 1996 to 2006. The key words were: nosocomial infection and mortality and pediatrics/neonate/ newborn/child/infant/adolescent. The risk factors found to be associated with mortality were: nosocomial infection itself, leukemia, lymphopenia, neutropenia, corticosteroid therapy, multiple organ failure, previous antimicrobial therapy, catheter use duration, candidemia, cancer, bacteremia, age over 60, invasive procedures, mechanical ventilation, transport out of the pediatric intensive care unit, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Burkholderia cepacia infections, acute physiology and chronic health evaluation (APACHE) II scores over 15. Among these factors, the only one that can be minimized is inadequate antimicrobial treatment, which has proven to be an important contributor to hospital mortality in critically-ill patients. There is room for further prognosis research on this matter to determine local differences. Such research requires appropriate epidemiological design and statistical analysis so that pediatric death due to nosocomial infection can be reduced and health care quality improved in pediatric hospitals.     

Antimicrobial resistance in hospital organisms and its relation to antibiotic use

Organisms causing nosocomial infection are frequently resistant to antimicrobial agents. Studies of the reasons for this have been hindered by difficulties in defining terms, by selection biases, by artifacts produced by study methods, and by failure to control for confounding variables. Major factors leading to increased prevalence of resistant organisms in hospitals are changes in organisms causing nosocomial infection (due in part to changes in characteristics of hospital populations and in procedures and instruments used in patient care), increasing prevalence of resistance in bacteria causing community-acquired infection, and use of antimicrobial agents. A causal relationship between antibiotic usage and resistance of hospital organisms is supported by consistent association and concurrent variation in several populations, presence of a dose-response pattern, and existence of a reasonable biologic model to explain the relationship. Major influences on emergence of resistant hospital bacteria include antimicrobial effects in treated individuals, mechanisms for transfer of resistance between bacteria, and routes of transmission within the hospital for bacteria or their resistance factors. Barrier isolation techniques can help control resistant hospital bacteria. However, virtually all reports agree that careful, discriminating use of antimicrobial agents remains the keystone for minimizing this problem. This need must be communicated more effectively to prescribers.     

抗菌药物预防性应用在重型病毒性肝炎治疗中的价值

目的:调查抗菌药物预防性应用对重型病毒性肝炎医院感染的影响,并探讨其应用机制。方法:选择入院前1周未经抗菌治疗、入院时无感染征象、住院时间超过72小时的重型肝炎病例,根据临床分期及抗菌药物应用情况分组、对照研究。结果:159例患者中76例发生医院感染,未预防性应用抗菌药物组(A组)、静脉注射第三代头孢菌素组(B组)及半合成青霉素组(C组)医院感染率分别为56.16％(41/73)、34.01％(17/50)和50.0％(18/36),B组明显低于A组(P<0.05);B组医院感染发生时间较A组明显推迟,B组可降低中期重型肝炎的病死率、与A组比较有显著性差异(16.67％ us 50.0％,P<0.05)。结论:早期患者应用预防性抗菌药物可推迟医院感染发生时间,但对降低医院感染率及病死率无统计学意义;中、晚期患者预防性应用第三代头孢菌素对推迟医院感染发生时间、降低医院感染率及病死率是有效的。     

National nosocomial infection surveillance system-based study in Iran: additional hospital stay attributable to nosocomial infections

BACKGROUND: Nosocomial infection is a serious health and financial problem. The purpose of this study was to determine the extra hospital stay attributable to nosocomial infections for patients undergoing surgery. METHOD: All patients undergoing surgery admitted from March 1, 1999, to February 28, 2000, to the 38-bed general surgery ward within a university hospital in Shiraz, Iran, were included in this study. The study was planned as a pairwise-matched case-control study nested in cohort design. A case was defined as any patient with 1 of 4 of the following nosocomial infections: urinary tract infection; surgical site infection; bloodstream infection; or pneumonia, whereby definitions for the nosocomial infections were on the basis of National Nosocomial Infection Surveillance system definitions. For each patient, an appropriate match was selected, which resulted in 69 pairs of study patients. RESULTS: The total incidence of nosocomial infection during the study period was 17.59%. The mean extra length of hospitalization as a result of all major kinds of nosocomial infections was 6.62 days total, which was obtained using 4.4, 5.33, 8.73, and 9.2 extra days for urinary tract infection, pneumonia, surgical site infection, and bloodstream infection, respectively. CONCLUSION: Nosocomial infections add considerable costs to the health care system in Iran. Therefore, the development of strategies and concepts to reduce the incidence of nosocomial infections is cost-effective and warranted, and an appropriate surveillance system on the basis of international criteria is the cornerstone for this task.     

Nosocomial pneumonia in the 1990s: update of epidemiology and risk factors

Hospital-acquired pneumonia is the second most common nosocomial infection in the United States. Aspiration appears to be the major route for the entry of microorganisms into the lower respiratory tract. Nosocomial pneumonia may be caused by bacteria, viruses and fungi. Aerobic gram-negative bacilli and Staphylococcus aureus are the most common etiologic agents, but infection is usually polymicrobial. Risk factors for nosocomial pneumonia include host variables, colonization with nosocomial pathogens, and impaired response of pulmonary defenses to the microbial challenge. Bacteria causing nosocomial pneumonia may be part of the patient's endogenous flora, originate from the hands of hospital personnel, or result from the use of invasive devices. The mechanically ventilated patient has multiple risk factors that contribute to the high rate of nosocomial pneumonia. An understanding of the epidemiology and risk factors for nosocomial pneumonia is fundamental for implementation of preventive strategies to reduce patient morbidity, mortality, and hospital costs.     

An evaluation of the efficacy of a hospital infection control program.

To establish the credibility of the hospital infection control program at a major southeastern medical university hospital, the incidence rates of nosocomial infections were analyzed statistically following the implementation of an extensive infection control program. Continuous hospital-wide surveillance included documentation of all detected nosocomial infections by both site and service. Chi-square analysis of the incidence of infection during the years 1977 to 1979 revealed significant decreases in several distinct areas. The overall incidence rate of infection steadily declined from 100.8/1000 admissions in 1977 to 59.9/1000 in 1979. Decreases in the incidence of urinary tract, respiratory tract, and surgical wound infections were primarily involved. Analysis of incidence rates by service revealed that general surgery was responsible for much of the observed decrease. In contrast, none of the intensive care units exhibited a significant decline in morbidity rates over the 3-year period. It is concluded that involvement of infection control personnel at all levels of patient care as a part of a sophisticated hospital infection control program can result in a significant reduction in the incidence of nosocomial infections.