Critical points and potential pitfalls of outbreak of IMP-1-producing carbapenem-resistant Pseudomonas aeruginosa among kidney transplant recipients: a case-control study.

BACKGROUND: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) infection after kidney transplantation (KT) is associated with high mortality. AIM: To analyse an outbreak of infection/colonization with IMP-1-producing CRPA on a KT ward. METHODS: A case-control study was conducted. Cases were identified through routine surveillance culture and real-time polymerase chain reaction for carbapenemase performed directly from rectal swab samples. Controls were randomly selected from patients hospitalized on the same ward during the same period, at a ratio of 3:1. Strain clonality was analysed through pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing was performed for additional strain characterization. FINDINGS: CRPA was identified in 37 patients, in 51.4% through surveillance cultures and in 49.6% through clinical cultures. The median persistence of culture positivity was 42.5 days. Thirteen patients (35.1%) presented a total of 15 infections, of which seven (46.7%) were in the urinary tract; among those, 30-day mortality rate was 46.2%. PFGE analysis showed that all of the strains shared the same pulsotype. Multilocus sequence typing analysis identified the sequence type as ST446. Risk factors for CRPA acquisition were hospital stay >10 days, retransplantation, urological surgical reintervention after KT, use of carbapenem or ciprofloxacin in the last three months and low median lymphocyte count in the last three months. CONCLUSION: KT recipients remain colonized by CRPA for long periods and could be a source of nosocomial outbreaks. In addition, a high proportion of such patients develop infection. During an outbreak, urine culture should be added to the screening protocol for KT recipients.

Bloodstream infection caused by extensively drug-resistant Acinetobacter baumannii in cancer patients: high mortality associated with delayed treatment rather than with the degree of neutropenia.

This study aimed to describe severe infections with extensively drug-resistant Acinetobacter baumannii-calcoaceticus complex (XDR-ABC), as well as to investigate risk factors for mortality, in cancer patients. It was a retrospective study including all patients diagnosed with XDR-ABC bacteraemia during hospitalization in the intensive care unit of a cancer hospital between July 2009 and July 2013. Surveillance cultures were collected weekly during the study period, and clonality was analysed using pulsed field gel electrophoresis (PFGE). We analysed underlying diseases, oncology therapy, neutrophil counts, infection site and management of infection, in terms of their correlation with 30-day mortality. During the study period, 92 patients with XDR-ABC bacteraemia were identified, of whom 35 (38.0%) were patients with haematological malignancy. We identified XDR-ABC strains with four different profile patterns, 91.3% of patients harbouring the predominant PFGE type. Of the 92 patients with XDR-ABC bacteraemia, 66 (71.7%) had central line-associated bloodstream infections; infection occurred during neutropenia in 22 (23.9%); and 58 (63.0%) died before receiving the appropriate therapy. All patients were treated with polymyxin, which was used in combination therapy in 30 of them (32.4%). The 30-day mortality rate was 83.7%. Multivariate analysis revealed that septic shock at diagnosis of XDR-ABC infection was a risk factor for 30-day mortality; protective factors were receiving appropriate therapy and invasive device removal within the first 48 h. Among cancer patients, ineffective management of such infection increases the risk of death, more so than do features such as neutropenia and infection at the tumour site.

Treatment of KPC-producing Enterobacteriaceae: suboptimal efficacy of polymyxins.

Treatment of Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae infections (KPC-EI) remains a challenge. Combined therapy has been proposed as the best choice, but there are no clear data showing which combination therapy is superior. Our aim was to evaluate the effectiveness of antimicrobial regimens for treating KPC-EI. This was a retrospective cohort study of KPC-EI nosocomial infections (based on CDC criteria) between October 2009 and June 2013 at three tertiary Brazilian hospitals. The primary outcomes were the 30-day mortality for all infections and the 30-day mortality for patients with bacteraemia. Risk factors for mortality were evaluated by comparing clinical variables of survivors and nonsurvivors. In this study, 118 patients were included, of whom 78 had bacteraemia. Catheter-related bloodstream infections were the most frequent (43%), followed by urinary tract infections (n = 27, 23%). Monotherapy was used in 57 patients and combined treatment in 61 patients. The most common therapeutic combination was polymyxin plus carbapenem 20 (33%). Multivariate analysis for all infections (n = 118) and for bacteremic infections (n = 78) revealed that renal failure at the end of treatment, use of polymyxin and older age were prognostic factors for mortality. In conclusion, polymyxins showed suboptimal efficacy and combination therapy was not superior to monotherapy.

Infection with Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae in cancer patients.

Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kp) is an emergent pathogen in healthcare-associated infections (HAIs). The aim of this study was to describe HAIs due to KPC-Kp, as well as identify mortality risk factors in cancer patients. In patients diagnosed with HAIs due to KPC-Kp between January 2009 and July 2013, we evaluated only the first infection episode of each patient, analyzing mortality separately for patients treated for ≥48 h with at least one antimicrobial agent proven to display in vitro activity against KPC-Kp. We evaluated variables related to the malignancy, the severity and characteristics of the HAI, and the antimicrobial therapy. We identified 83 HAIs due to KPC-Kp. The 30-day mortality was 57.8 % for all infections and 72.7 % for bacteremic infections. Of the 83 patients, 60 patients received ≥48 h of appropriate treatment and 44 (53 %) developed bacteremia. Ten patients (12 %) were neutropenic at HAI diagnosis and 33 (39.8 %) had infection at the tumor site. The most common HAI was urinary tract infection, seen in 26 patients (31.3 %), followed by primary bloodstream infection, seen in 24 patients (28.9 %). Forty-four patients (73.3 %) received combination antimicrobial therapy, most often including polymyxin (68.3 %). Risk factors for 30-day mortality are high sequential organ failure assessment (SOFA) score, need for intensive care stay at diagnosis of infection, and acute kidney injury; the removal of invasive devices related to infection and treatment with effective antibiotics for KPC-Kp are protective factors. In cancer patients, high mortality is associated with HAI due to KPC-Kp and mortality risk factors are more often related to acute infection than to the underlying disease.

Polymyxin use as a risk factor for colonization or infection with polymyxin-resistant Acinetobacter baumannii after liver transplantation.

INTRODUCTION: Acinetobacter baumannii is a leading agent of healthcare-associated infection. The objective of this study was to evaluate cases of colonization or infection with polymyxin-resistant A. baumannii (PRAB) in liver transplant recipients and to identify the risk factors for the acquisition of PRAB. METHODS: We evaluated all patients undergoing liver transplantation (LT) between January and November of 2011. The exclusion criterion was death within the first 72 h after transplant. Patients were screened for PRAB through weekly rectal and inguinal swabs during their stay in the intensive care unit (ICU) and at ICU discharge. Patients who came from other hospitals or had been treated in the emergency room for >72 h were screened at ICU admission. The minimum inhibitory concentrations (MICs) for polymyxins were determined by broth microdilution, and clonality was determined by pulsed-field gel electrophoresis. The stepwise logistic regression was used to identify risk factors related to acquisition of PRAB, and Cox forward regression used to identify risk factors for 60-day mortality. RESULTS: We evaluated 65 patients submitted to LT, among whom PRAB was isolated in 7, 4 of whom developed infection. The MICs for polymyxin E ranged from 16 to 128 mg/mL. All patients with PRAB required dialysis. The median time of polymyxin use before PRAB isolation was 21 days. These 4 included 1 case of primary bloodstream infection (BSI), which was treated with the carbapenem-polymyxin combination; 1 case of surgical site infection, which was treated with gentamicin, polymyxin, ampicillin-sulbactam, and tigecycline; and 2 cases of pneumonia, treated with the combination of carbapenem-polymyxin. In the case of BSI and in 1 of the cases of pneumonia, the treatment was considered successful. Mortality was 71% among the cases, compared with 33% among the non-cases. CONCLUSION: In the final model of the survival analysis, PRAB colonization or infection after LT was independently associated with mortality. One predominant clone was identified. The only risk factor identified in the multivariate analysis was polymyxin use. PRAB was an agent with high mortality, and the most important risk factor associated with colonization or infection for such bacterium was polymyxin use.

Molecular Detection of Leishmania in Sand Flies (Diptera: Psychodidae: Phlebotominae) Collected in the Caititu Indigenous Reserve of the Municipality of Lábrea, State of Amazonas, Brazil.

Phlebotominae sand flies are of medical importance because they are vectors of human pathogens, such as protozoa of the genus Leishmania Ross, etiological agent of American cutaneous leishmaniasis (ACL). In Lábrea, a municipality in the state of Amazonas, Brazil, ACL is primarily associated with subsistence activities, such as collection and extraction of forest products, undertaken by both indigenous and nonindigenous people. Data on ACL in indigenous populations are scarce, such that there is little information on the identity of the etiologic agent(s), reservoir host(s) and insect vector(s). The aim of this work was to study the sand fly fauna collected during an 8-d surveillance of different habitats in the Indigenous Reserve Caititu, Lábrea. In total, 1,267 sand flies were collected in different habitats for eight consecutive days, of which 819 (64.6%) were females and 448 (35.4%) males, from 10 genera and 32 species. The most abundant genera were Psychodopygus (34.3%), Trichophoromyia (22.9%), and Nyssomyia (15.3%). The most abundant species were Trichophoromyia ubiquitalis (Mangabeira) (n = 235, 18.5%), Psychodopygus davisi (Root) (n = 228, 18.0%) and Nyssomyia antunesi (Coutinho) (n = 135, 10.7%). Direct sequencing of polymerase chain reaction products demonstrated the presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis in the following species of sand flies: Evandromyia apurinan (Shimabukuro, Silveira, & Silva), Nyssomyia umbratilis (Ward & Fraiha), Nyssomyia yuilli yuilli (Young & Porter), Ps. davisi, Sciopemyia servulolimai (Damasceno & Causey), and Th. ubiquitalis. The presence of natural infection by Leishmania detected in the sand fly species investigated in this study suggests their possible role in the transmission cycle of ACL in the studied area.

Infection rate and risk factors associated with infections related to external ventricular drain.

OBJECTIVE: To describe incidence rates and risk factors associated with external ventricular drain (EVD)-related infections at a tertiary Brazilian teaching hospital. METHODS: The patient cohort consisted of all patients at a major teaching hospital in Brazil with an EVD during the period 1 April 2007 to 30 June 2008 (15 months). Patients were followed up for 30 days after catheter removal. According to the Center for Diseases Control and Prevention criteria for meningitis/ventriculitis, all of the central nervous system (CNS) infections that occurred during this period could be considered to be meningitis or ventriculitis related to EVD placement. Infection rates were calculated using different denominators, such as (1) per patient (incidence), (2) per procedure, and (3) per 1,000 catheter-days (drain-associated infection rate). Patient demographic data, medical history of underlying diseases, antibiotic prophylaxis usage, American Society of Anesthesiologists Score classification, duration of surgery and hospitalization, length of time the EVD was in place, and overall mortality were evaluated during the study period. A logistic regression model was developed to identify factors associated with infection. RESULTS: A total of 119 patients, 130 EVD procedures, and 839 catheter-days were evaluated. The incidence of infection was 18.3%, the infection rate was 16.9% per procedure, and the drain-associated infection rate was 22.4 per 1,000 catheter-days; 77% of the infections were caused by Gram-negative micro-organisms. Only 75% of patients received antibiotic prophylaxis. The infection rate increased with length of the hospital stay. The length of time the catheter was in place was the only independent risk factor associated with infection (p = 0.0369). CONCLUSION: The incidence of EVD-related infections is high in our hospital, Gram-negative micro-organisms were the most frequent causal agents identified and length of time that the catheter was in place contributed to the infection rate.

Surveillance Programme for Healthcare Associated Infections in the State of São Paulo, Brazil. Implementation and the first three years' results.

Governmental programmes should be developed to collect and analyse data on healthcare associated infections (HAIs). This study describes the healthcare setting and both the implementation and preliminary results of the Programme for Surveillance of Healthcare Associated Infections in the State of São Paulo (PSHAISP), Brazil, from 2004 to 2006. Characterisation of the healthcare settings was carried out using a national database. The PSHAISP was implemented using components for acute care hospitals (ACH) or long term care facilities (LTCF). The components for surveillance in ACHs were surgical unit, intensive care unit and high risk nursery. The infections included in the surveillance were surgical site infection in clean surgery, pneumonia, urinary tract infection and device-associated bloodstream infections. Regarding the LTCF component, pneumonia, scabies and gastroenteritis in all inpatients were reported. In the first year of the programme there were 457 participating healthcare settings, representing 51.1% of the hospitals registered in the national database. Data obtained in this study are the initial results and have already been used for education in both surveillance and the prevention of HAI. The results of the PSHAISP show that it is feasible to collect data from a large number of hospitals. This will assist the State of São Paulo in assessing the impact of interventions and in resource allocation.

Outbreak of surgical infection caused by non-tuberculous mycobacteria in breast implants in Brazil.

SUMMARY: We investigated an outbreak caused by non-tuberculous mycobacteria (NTM) related to breast implant surgery in the city of Campinas, Brazil, by means of a retrospective cohort and molecular epidemiological study. A total of 492 records of individuals having breast surgery in 12 hospitals were evaluated. Twelve isolates were analysed using four different molecular typing methods. There were 14 confirmed cases, 14 possible cases and one probable case. One probable, nine possible and 12 confirmed cases were included in a cohort study; all occurred in eight of the hospitals and the confirmed cases in five. Univariate analysis showed that patients who had had breast reconstruction surgery in hospitals A and B were more likely to have NTM infections. No risk factor was independently associated with NTM infection in the multivariate model. The isolates obtained from patients at each hospital showed different molecular patterns, excluding isolates from hospital C that repeatedly showed the same genotype for approximately one year. In conclusion, this outbreak was caused by polyclonal strains at different institutions, and in one hospital a unique genotype caused most cases. No specific risk factors were found.