Luis Fernando Aranha Camargo

Nosocomial Bloodstream Infections in Brazilian Hospitals: Analysis of 2,563 Cases from a Prospective Nationwide Surveillance Study

ABSTRACT Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality. Data from a nationwide, concurrent surveillance study, Brazilian SCOPE (Surveillance and Control of Pathogens of Epidemiological Importance), were used to examine the epidemiology and microbiology of nBSIs at 16 Brazilian hospitals. In our study 2,563 patients with nBSIs were included from 12 June 2007 to 31 March 2010. Ninety-five percent of BSIs were monomicrobial. Gram-negative organisms caused 58.5% of these BSIs, Gram-positive organisms caused 35.4%, and fungi caused 6.1%. The most common pathogens (monomicrobial) were Staphylococcus aureus (14.0%), coagulase-negative staphylococci (CoNS) (12.6%), Klebsiella spp. (12.0%), and Acinetobacter spp. (11.4%). The crude mortality was 40.0%. Forty-nine percent of nBSIs occurred in the intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 622 patients (24.3%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (70.3%). Methicillin resistance was detected in 157 S. aureus isolates (43.7%). Of the Klebsiella sp. isolates, 54.9% were resistant to third-generation cephalosporins. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 55.9% and 36.8%, respectively, were resistant to imipenem. In our multicenter study, we found high crude mortality and a high proportion of nBSIs due to antibiotic-resistant organisms.

The use of sirolimus in ganciclovir-resistant cytomegalovirus infections in renal transplant recipients.

Abstract:  Background:  The widespread use of prophylactic ganciclovir and anti‐lymphocyte/thymocyte therapies are associated with increased induction of ganciclovir‐resistant cytomegalovirus (CMV) strains. The use of sirolimus has been associated with a lower incidence of CMV infection in transplant recipients. We questioned whether it could also be effective as a therapeutic treatment of resistant CMV infection.

Brazilian guidelines for the management of candidiasis - a joint meeting report of three medical societies: Sociedade Brasileira de Infectologia, Sociedade Paulista de Infectologia and Sociedade Brasileira de Medicina Tropical.

Candida infections account for 80% of all fungal infections in the hospital environment, including bloodstream, urinary tract and surgical site infections. Bloodstream infections are now a major challenge for tertiary hospitals worldwide due to their high prevalence and mortality rates. The incidence of candidemia in tertiary public hospitals in Brazil is approximately 2.5 cases per 1000 hospital admissions. Due to the importance of this infection, the authors provide a review of the diversity of the genus Candida and its clinical relevance, the therapeutic options and discuss the treatment of major infections caused by Candida. Each topography is discussed with regard to epidemiological, clinical and laboratory diagnostic and therapeutic recommendations based on levels of evidence.

Bloodstream infection after kidney transplantation: epidemiology, microbiology, associated risk factors, and outcome.

Background. Bloodstream infection (BSI) is associated with both relevant morbidity and mortality rates after kidney transplantation. Methods. From January 1, 2000 to January 31, 2006, all episodes of BSI were retrospectively assessed through the review of medical records in two tertiary teaching Hospitals in Sao Paulo, Brazil, where 3308 transplant procedures were performed during this period. Contaminants and polymicrobial infections were excluded. The main objectives of the study were to describe clinical and microbiologic aspects of BSI, as well as risk factors for both BSI and mortality from these infections in kidney transplant patients. Results. BSI was detected in 185 patients, with onset after a median of 235 days after transplantation; 62% occurred after 6 months. The primary source of infection was the urinary tract in 37.8%. The most prevalent pathogen overall was Escherichia coli (30.3%). Risk factors for early acquired BSI (first 6 months after transplantation) were acute rejection, ureteric stent placement, and receiving an organ from a deceased donor. For late BSI (after 6 months), associated risk factors were acute rejection, Charlson Comorbidity Score more than or equal to 3, and receiving an organ from a deceased donor. Risk factors related to 30-day mortality were Acute Physiology and Chronic Health Evaluation II Score more than or equal to 20, shock, and respiratory failure. Conclusions. BSI is most frequently a consequence of urinary tract infection, with a high prevalence of gram-negative bacilli. Severity of disease was the main determinant of 30-day mortality after BSI, and based on the knowledge of risk factors, some interventions are suggested for reducing the rate of BSI after transplantation.

Comparison between antigenemia and a quantitative-competitive polymerase chain reaction for the diagnosis of cytomegalovirus infection after heart transplantation.

Background. Antigenemia and quantitative polymerase chain reaction (PCR) are widely used for cytomegalovirus (CMV) diagnosis after heart transplantation due to their enhanced predictive values for disease detection when specific cut-off values are used. The purpose of this study was to compare, in the same patient setting, the predictive values of quantitative PCR and antigenemia for CMV disease detection, using specific cut-off values. Methods. Thirty heart transplant receptors were prospectively monitored for active CMV infection and disease detection, using quantitative PCR and antigenemia. Positive and negative predictive values for CMV disease detection were calculated using cut-off values for both antigenemia (5 and 10 positive cells/300,000 neutrophils) and quantitative-PCR (50,000 and 100,000 copies/106 leukocytes). Results. Active CMV infection was diagnosed in 93.3% of patients and CMV disease in 23.3%. The positive and negative predictive (%) values for CMV disease detection were 35/100 and 46.7/100, respectively, for quantitative PCR and antigenemia. Using 5 and 10 positive cells/300,000 neutrophils as cut-off values for antigenemia, the positive and negative predictive values (%) for disease detection were respectively 63.6/100 and 70/100. For quantitative PCR, the positive and negative predictive values (%) for cut-off values of 50,000 and 100,000 copies/106 leukocytes were 53.8/100 and 60/94.1, respectively. Conclusion. In our series, antigenemia and quantitative-PCR had enhanced and similar predictive values for CMV disease detection when specific cut-off values were used. The choice between these two methods for disease detection may rely less on their efficiency and more on the experience and familiarity with them.

Nosocomial Bloodstream Infections in Brazilian Pediatric Patients: Microbiology, Epidemiology, and Clinical Features

Background Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality and are the most frequent type of nosocomial infection in pediatric patients. Methods We identified the predominant pathogens and antimicrobial susceptibilities of nosocomial bloodstream isolates in pediatric patients (≤16 years of age) in the Brazilian Prospective Surveillance for nBSIs at 16 hospitals from 12 June 2007 to 31 March 2010 (Br SCOPE project). Results In our study a total of 2,563 cases of nBSI were reported by hospitals participating in the Br SCOPE project. Among these, 342 clinically significant episodes of BSI were identified in pediatric patients (≤16 years of age). Ninety-six percent of BSIs were monomicrobial. Gram-negative organisms caused 49.0% of these BSIs, Gram-positive organisms caused 42.6%, and fungi caused 8.4%. The most common pathogens were Coagulase-negative staphylococci (CoNS) (21.3%), Klebsiella spp. (15.7%), Staphylococcus aureus (10.6%), and Acinetobacter spp. (9.2%). The crude mortality was 21.6% (74 of 342). Forty-five percent of nBSIs occurred in a pediatric or neonatal intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 95 patients (27.8%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (66.4%). Methicillin resistance was detected in 37 S. aureus isolates (27.1%). Of the Klebsiella spp. isolates, 43.2% were resistant to ceftriaxone. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 42.9% and 21.4%, respectively, were resistant to imipenem. Conclusions In our multicenter study, we found a high mortality and a large proportion of gram-negative bacilli with elevated levels of resistance in pediatric patients.

Candida glabrata: an emerging pathogen in Brazilian tertiary care hospitals

Candida glabrata is an infrequent cause of candidemia in Brazilian public hospitals. We investigated putative differences in the epidemiology of candidemia in institutions with different sources of funding. Prospective laboratory-based surveillance of candidemia was conducted in seven private and two public Brazilian tertiary care hospitals. Among 4,363 episodes of bloodstream infection, 300 were caused by Candida spp. (6.9%). Incidence rates were significantly higher in public hospitals, i.e., 2.42 vs. 0.91 episodes per 1,000 admissions (P< 0.01). Patients in private hospitals were older, more likely to be in an intensive care unit and to have been exposed to fluconazole before candidemia. Candida parapsilosis was more frequently recovered as the etiologic agent in public (33% vs. 16%, P< 0.001) hospitals, whereas C. glabrata was more frequently isolated in private hospitals (13% vs. 3%, P < 0.001). Fluconazole resistance among C. glabrata isolates was more frequent in private hospitals (76.5% vs. 20%, P = 0.02). The 30-day mortality was slightly higher among patients in public hospitals (53% vs. 43%, P = 0.10). Candida glabrata is an emerging pathogen in private institutions and in this setting, fluconazole should not be considered as a safe option for primary therapy of candidemia.

Prevalence of vancomycin-resistant Enterococcus fecal colonization among kidney transplant patients

BackgroundEnd stage renal disease patients are at risk of Vancomycin-Resistant Enterococcus (VRE) infections. The first reports of VRE isolation were from hemodialysis patients. However, to date, VRE fecal colonization rates as well as associated risk factors in kidney transplant patients have not yet been established in prospective studies.MethodsWe collected one or two stool samples from 280 kidney transplant patients and analysed the prevalence of VRE and its associated risk factors. Patients were evaluated according to the post-transplant period: group 1, less than 30 days after transplantation (102 patients), group 2, one to 6 months after transplantation (73 patients) and group 3, more than 6 months after transplantation (105 patients).ResultsThe overall prevalence rate of fecal VRE colonization was 13.6% (38/280), respectively 13.7% for Group 1, 15.1% for group 2 and 12.4% for group 3. E. faecium and E. faecalis comprised 50% of all VRE isolates. No immunologic variables were clearly correlated with VRE colonization and no infections related to VRE colonization were reported.ConclusionFecal VRE colonization rates in kidney transplant patients were as high as those reported for other high-risk groups, such as critical care and hemodialysis patients. This high rate of VRE colonization observed in kidney transplant recipients may have clinical relevance in infectious complications.

Secular trends of candidemia in a tertiary care hospital

BACKGROUND Candidemias account for 8% to 15% of hospital-acquired bloodstream infections. They have been associated with previous exposure to antimicrobials and are considered high-morbidity infections with high treatment costs. This study characterizes candidemias in a tertiary care hospital and assesses their incidence rates, clinical and microbiological features, and use of antifungals. METHODS We assessed hospital-acquired candidemias in the period from January 1997 to July 2007 in a high-complexity private hospital. RESULTS There were 151 cases of candidemia in 147 patients. The incidence rate was 0.74 episodes/1000 admissions. The mean age of the patients was 60 years (standard deviation +/- 24.9), and the mean length of hospital stay before the blood culture identified candidemia was 40.9 days (standard deviation +/- 86.3). The in-hospital mortality rate was 44.2%. C albicans was isolated in 44% (n = 67) of the cases, and no difference in mortality rates was found between species (Candida albicans vs C non-albicans, P = .6). The average use of antifungals in the period was 104.0 defined daily dose/1000 patient-days. CONCLUSION We found a high mortality rate associated to candidemia events and an increasingly important role of Candida non-albicans. New approaches to health care-related infection control and to defining prophylactic and preemptive therapies should change this scenario in the future.

Sequential cytomegalovirus antigenemia monitoring in kidney transplant patients treated with antilymphocyte antibodies

Abstract: Background: Antilymphocyte antibodies (ALA) use is related to disseminated cytomegalovirus (CMV) disease after kidney transplantation. Strict surveillance of CMV infection, preemptive antiviral treatment or concomitant ganciclovir and ALA use are proposed as an attempt to prevent related clinical complications. Our objective was to describe the pattern of CMV infection, based on sequential antigenemia detection, after ALA treatment.