Performance of two methods of carbapenem-resistant Enterobacterales surveillance on a kidney transplant ward: selective culture of and real-time PCR directly from rectal swabs.

BACKGROUND: Infection with carbapenem-resistant Enterobacterales (CRE) is associated with a high mortality rate in kidney transplant recipients, and colonization with CRE is one of the major risk factors for CRE infection. There is, therefore, a need to improve the capacity to detect colonization with CRE among inpatients. METHODS: In this prospective study, we compared the performance of real-time PCR for carbapenemase directly from rectal swabs with that of conventional CRE surveillance culture in all patients admitted to a kidney transplant ward between February 2019 and March 2020. Surveillance culture and real-time PCR were performed at admission and weekly until hospital discharge. Two perineum-rectal swabs were collected: one for culture and one for PCR. RESULTS: We collected 905 paired samples for CRE surveillance from 399 patients, of whom 347 (87.0%) were kidney transplant recipients and 52 were waiting list patients. CRE was detected by culture and/or PCR in 75 patients (18.8%). Positivity for CRE was identified by PCR in 62 (15.5%) of the 399 patients and by culture in 55 (13.8%); 20 (5.0%) of the patients tested positive only on PCR, and 13 (3.3%) tested positive only on culture. The most common carbapenemase and species were, respectively, blaKPC (in 85.5%) and Klebsiella pneumoniae (in 80.0%). Infection with CRE occurred in 21.6% of the colonized patients, those cases occurred only among kidney transplant recipients. None of the patients who tested negative on culture developed CRE infection. CONCLUSION: In conclusion, the two methods are complementary and could be useful in a scenario of high CRE prevalence.

Immune complexes as a tool for strongyloidiasis immunodiagnosis in kidney and liver transplant candidate.

Strongyloidiasis is a chronic and asymptomatic infection in immunocompetent patients. Immunocompromised patients, such as organ transplant candidates, can develop severe forms of this disease, and the best way to prevent progression to these forms is early diagnosis. Serological techniques using specific IgG and immune complexes (IC) detection can help in the diagnosis of these patients. This study aimed to detect specific anti-Strongyloides IC and IgG antibodies in kidney transplant (KT) and liver transplant (LT) candidates. A total of 100 blood samples was collected from transplant candidates (50 blood samples each from KT and LT candidates). Serum was obtained and analysed using enzyme-linked immunosorbent assay for IC and IgG detections. The IC levels showed frequencies of 18% and 2% in the KT and LT groups, respectively, whereas anti-Strongyloides IgG was detected in 34% and 12% of KT and LT candidates, respectively. The correlation between IC and IgG detection is poor in KT candidates, while in LT candidates, there is a significant positive correlation. The detection of IC can be an additional tool for the diagnosis of strongyloidiasis, especially when associated with the detection of specific IgG anti-Strongyloides antibodies.

Effect on Antimicrobial Resistance of a Policy Restricting Over-the-Counter Antimicrobial Sales in a Large Metropolitan Area, São Paulo, Brazil.

Although restricting over-the-counter (OTC) antimicrobial drug sales is recommended globally, no data track its effect on antimicrobial resistance (AMR) in bacteria. We evaluated the effect of a national policy restricting OTC antimicrobial sales, put in place in November 2010, on AMR in a metropolitan region of São Paulo, Brazil. We reviewed associations between antimicrobial sales from private pharmacies and AMR in 404,558 Escherichia coli and 5,797 Streptococcus pneumoniae isolates using a dynamic regression model based on a Bayesian approach. After policy implementation, a substantial drop in AMR in both bacterial species followed decreased amoxicillin and trimethoprim/sulfamethoxazole sales. Conversely, increased ciprofloxacin sales were associated with increased ciprofloxacin resistance, and extended spectrum ß-lactamases-positive E. coli isolates and azithromycin sales increases after 2013 were associated with increased erythromycin resistance in S. pneumoniae isolates. These findings suggest that restricting OTC antimicrobial sales may influence patterns of AMR, but multifaceted approaches are needed to avoid unintended consequences.

Carbapenem-resistant Enterobacteriaceae among kidney transplant recipients - insights on the risk of acquisition and CRE infection.

BACKGROUND: Kidney transplant recipients are a risk group for carbapenem-resistant Enterobacteriaceae infection. OBJECTIVES: This study aimed to identify risk factors for CRE acquisition and infection among kidney transplant recipients. METHODS: We conducted a case-control study; we defined the case as kidney transplant recipient with positive culture for carbapenem-resistant Enterobacteriaceae identified between January 2010 and February 2019. Controls were chosen among kidney transplant recipients hospitalized in the same period of cases (1:2). Surveillance culture for carbapenem-resistant Enterobacteriaceae was performed at admission and weekly during hospital stay. The risk factors analysis for carbapenem-resistant Enterobacteriaceae infection was performed among patients colonized by these bacteria. RESULTS: We identified 331 patients colonized with carbapenem-resistant Enterobacteriaceae; The median time from transplantation to first carbapenem-resistant Enterobacteriaceae positive culture was 42 days (range from 3 to 7399 days); 125(37.8%) patients developed infection; the most common site was urinary tract. Risk factors for carbapenem-resistant Enterobacteriaceae acquisition were recipient age >45-year, diabetes nephropathy, donor age >55-year, ureteral stent at kidney transplantation, delay of graft function, median lymphocytes count <800cells/mm3, and acute cellular rejection. Risk factors for carbapenem-resistant Enterobacteriaceae infection were recipient age at CRE acquisition >50-year; median lymphocytes count ≤700 cells/mm3, carbapenem use, and colonization by polymyxin-resistant strain. Patients colonized by polymyxin and carbapenem resistant Enterobacteriaceae strain who used carbapenem had a 93.8% probability of developing infection by this agent. CONCLUSION: Carbapenem-resistant Enterobacteriaceae acquisition after kidney transplant is related to graft conditions, immunosuppression degree. Among carbapenem-resistant Enterobacteriaceae colonized patients, special attention is needed for those harbouring polymyxin-resistant strains.

Efficacy of ß-lactam/ß-lactamase inhibitors to treat extended-spectrum beta-lactamase-producing Enterobacterales bacteremia secondary to urinary tract infection in kidney transplant recipients (INCREMENT-SOT Project).

BACKGROUND: Whether active therapy with ß-lactam/ß-lactamase inhibitors (BLBLI) is as affective as carbapenems for extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) bloodstream infection (BSI) secondary to urinary tract infection (UTI) in kidney transplant recipients (KTRs) remains unclear. METHODS: We retrospectively evaluated 306 KTR admitted to 30 centers from January 2014 to October 2016. Therapeutic failure (lack of cure or clinical improvement and/or death from any cause) at days 7 and 30 from ESBL-E BSI onset was the primary and secondary study outcomes, respectively. RESULTS: Therapeutic failure at days 7 and 30 occurred in 8.2% (25/306) and 13.4% (41/306) of patients. Hospital-acquired BSI (adjusted OR [aOR]: 4.10; 95% confidence interval [CI]: 1.50-11.20) and Pitt score (aOR: 1.47; 95% CI: 1.21-1.77) were independently associated with therapeutic failure at day 7. Age-adjusted Charlson Index (aOR: 1.25; 95% CI: 1.05-1.48), Pitt score (aOR: 1.72; 95% CI: 1.35-2.17), and lymphocyte count ≤500 cells/µL at presentation (aOR: 3.16; 95% CI: 1.42-7.06) predicted therapeutic failure at day 30. Carbapenem monotherapy (68.6%, primarily meropenem) was the most frequent active therapy, followed by BLBLI monotherapy (10.8%, mostly piperacillin-tazobactam). Propensity score (PS)-adjusted models revealed no significant impact of the choice of active therapy (carbapenem-containing vs any other regimen, BLBLI- vs carbapenem-based monotherapy) within the first 72 hours on any of the study outcomes. CONCLUSIONS: Our data suggest that active therapy based on BLBLI may be as effective as carbapenem-containing regimens for ESBL-E BSI secondary to UTI in the specific population of KTR. Potential residual confounding and unpowered sample size cannot be excluded (ClinicalTrials.gov identifier: NCT02852902).

Subtypes of Blastocystis sp. isolated in fecal samples from transplant candidates in São Paulo, Brazil.

Blastocystis sp. is an intestinal protozoan commonly found in fecal samples of many animal species, including humans, but poorly studied in transplant candidates. The aim of this study was to evaluate the occurrence and molecular identification of Blastocystis sp. in fecal samples from transplant candidates. A polymerase chain reaction was performed using specific primers for Blastocystis ribosomal DNA. The DNA sequences obtained were aligned and compared with other sequences from the GenBank and MLST databases. The analyzed samples showed a positivity of 16% (24 of 150) for Blastocystis sp. The highest occurrence was observed in renal transplant candidates (31.4%), followed by hepatic transplant candidates (10.4%) and candidates for bone marrow transplantation (5.9%). Subtype (ST) 3 (45.8%) was the most prevalent among the isolates, followed by ST1 (37.5%), ST2 (12.5%), and ST7 (4.2%). This is the first study of molecular identification Blastocystis sp. in transplant candidates. Our results confirmed that ST3 was the most common subtype in transplant candidates and reinforce the importance of new studies to investigate of Blastocystis sp. in these patients.

Fatal Yellow Fever in a Kidney Transplant Patient.

A kidney-transplanted patient, unvaccinated against yellow fever (YF), developed high fever, progressed rapidly to hepatic insufficiency and coma, and died 8 days later. Real-time polymarase chain reaction for YF virus collected on the seventh day of symptoms was positive. Autopsy showed disseminated infection and midzonal hepatitis with apoptotic hepatocytes and minimal inflammatory reaction.

The role of therapy with aminoglycoside in the outcomes of kidney transplant recipients infected with polymyxin- and carbapenem-resistant Enterobacteriaceae.

Kidney transplant recipients are at risk for infections due to carbapenem-resistant Enterobacteriaceae (CRE). Polymyxin-resistant CRE (PR-CRE) infections are especially difficult to treat. The aim of this study was to characterize PR-CRE infections among kidney transplant recipients and identify risk factors for treatment failure. This retrospective cohort study involved all kidney transplant recipients with PR-CRE infection between 2013 and 2017 at our center. Minimal inhibitory concentrations for polymyxin B were determined by broth microdilution. Carbapenem-resistant genes (blaKPC, blaNDM, and blaOXA-48), aminoglycoside-resistance genes, and polymyxin-resistant gene mcr-1 were identified by polymerase chain reaction. All but one of the 47PR-CRE infections identified were due to Klebsiella pneumoniae. The most common type of infection (in 54.3%) was urinary tract infection (UTI). Monotherapy was used in 10 cases. Combined treatment regimens included double-carbapenem therapy in 19 cases, oral fosfomycin in 19, and amikacin in 13. Treatment failure occurred in 21 cases (45.7%). Clinical success was achieved 78.9% of patients who used aminoglycosides versus 37.0% of those who not used this drug (p = 0.007). Multivariate analysis showed diabetes mellitus to be a risk factor for treatment failure; amikacin use and UTI were found to be protective. Nine strains were RmtB producers. Although aminoglycosides constitute an important therapeutic option for PR-CRE infection, the emergence of aminoglycoside resistance could have a major impact on the management of CRE infection.

Variable sources of Bk virus in renal allograft recipients.

BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients' infection.

Role of Lock Therapy for Long-Term Catheter-Related Infections by Multidrug-Resistant Bacteria.

The management of long-term central venous catheter (LTCVC) infections by multidrug-resistant (MDR) bacteria in cancer patient is a challenge. The objectives of this study were to analyze outcomes in cancer patients with LTCVC-associated infection, identify risks for unfavorable outcomes, and determine the impact of MDR bacteria and antibiotic lock therapy (ALT) in managing such infections. We evaluated all LTCVC-associated infections treated between January 2009 and December 2016. Infections were reported in accordance with international guidelines for catheter-related infections. The outcome measures were 30-day mortality and treatment failure. We analyzed risk factors by Cox forward-stepwise regression. We identified 296 LTCVC-associated infections; 212 (71.6%) were classified as bloodstream infections (BSIs). The most common agent was Staphylococcus aureus Forty-six (21.7%) infections were due to MDR Gram-negative bacteria. ALT was used in 62 (29.2%) patients, with a 75.9% success rate. Risk factors identified for failure of the initial treatment were having a high sequential organ failure assessment (SOFA) score at diagnosis of infection and being in palliative care; introduction of ALT at the start of treatment was identified as a protective factor. Risk factors identified for 30-day mortality after LTCVC-associated infection were a high SOFA score at diagnosis, infection with MDR bacteria, and palliative care; introduction of ALT at the start of treatment, hematological malignancies, and adherence to an institutional protocol for the management of LTCVC-associated infection were identified as protective factors. Despite the high incidence of infection with MDR bacteria, ALT improves the outcome of LTCVC-associated infection in cancer patients.

Cytomegalovirus prophylaxis in seropositive renal transplant recipients receiving thymoglobulin induction therapy: Outcome and risk factors for late CMV disease.

BACKGROUND: Anti-thymocyte globulin (ATG) therapy is a risk factor for cytomegalovirus (CMV) disease in renal transplant (RTx) recipients and therefore antiviral prophylaxis is commonly used. We evaluated the outcome of our current policy of 90 days of CMV prophylaxis in seropositive recipients given ATG and the risk factors for the occurrence of CMV disease after prophylaxis. METHODS: We studied a retrospective cohort of 423 RTx (2010-2014) CMV-seropositive adults given ATG induction therapy. RESULTS: 54 (13%) patients developed CMV disease at a median of 163 days after transplant, of which 29 (54%) had viral syndrome and 25 (46%) had invasive disease. Median prophylaxis time (94 days) and immunosuppressive drugs were similar between groups (CMV vs no-CMV). Those with CMV disease had more deceased donors and higher donor age, lower lymphocyte count, and lower median eGFR at day 90. Multivariable logistic regression analysis at day 90 and 180 found that eGFR ≤40 ml/min/1.73 m2 (but not acute rejection) was associated with late CMV disease. In a separate validation cohort of 124 patients with 8% late CMV disease, eGFR ≤45 and lymphocyte count ≤800 cells/mm3 at the end of prophylaxis remained predictive of late CMV disease occurrence. CONCLUSIONS: These data indicate that antiviral prophylaxis adequately prevented CMV in seropositive recipients given ATG, but late disease still occurred. Low eGFR and low lymphocyte count at the end of prophylaxis may help identify patients at higher risk of CMV disease.

Molecular diagnosis of Strongyloides stercoralis among transplant candidates.

Strongyloidiasis can occur without any symptoms or as a potentially fatal hyperinfection or disseminated infection, principally in immunosuppressed patients. Our study aimed to evaluate the application of conventional polymerase chain reaction (cPCR) and real-time PCR (qPCR). Polymerase chain reaction (PCR) and real-time PCR (qPCR) targeting the 18S rRNA gene for detection of Strongyloides stercoralis infection among transplant candidates were applied in stool samples obtained from 150 transplant candidates, preliminarily analyzed by parasitological methods. S. stercoralis larvae were visualized in 15/150 (10.0%) transplant candidates by parasitological methods. DNA from S. stercoralis was amplified in 26/150 (17.3%) and 49/150 (32.7%) stool samples of transplant candidates, using cPCR and qPCR, respectively. The results suggest that molecular methods, especially qPCR, should be used as an additional tool for diagnostic of S. stercoralis infection among transplant candidates.

Rhizopus arrhizus and Fusarium solani Concomitant Infection in an Immunocompromised Host.

Neutropenic patients are at risk of the development of hyalohyphomycosis and mucormycosis. Correct identification is essential for the initiation of the specific treatment, but concomitant mold infections are rarely reported. We report one unprecedented case of concomitant mucormycosis and fusariosis in a neutropenic patient with acute myeloid leukemia. The patient developed rhino-orbital infection by Rhizopus arrhizus and disseminated infection by Fusarium solani. The first culture from a sinus biopsy grew Rhizopus, which was consistent with the histopathology report of mucormycosis. A second sinus biopsy collected later during the patient's clinical deterioration was reported as hyalohyphomycosis, and the culture yielded F. solani. Due to the discordant reports, the second biopsy was reviewed and two hyphae types suggestive of both hyalohyphomycetes and mucormycetes were found. The dual mold infection was confirmed by PCR assays from paraffinized tissue sections. Increased awareness of the existence of dual mold infections in at-risk patients is necessary. PCR methods in tissue sections may increase the diagnosis of dual mold infections. In case of sequential biopsies showing discrepant results, mixed infections have to be suspected.

New findings about trichodysplasia spinulosa-associated polyomavirus (TSPyV)--novel qPCR detects TSPyV-DNA in blood samples.

A new real-time PCR assay for trichodysplasia spinulosa-associated polyomavirus (TSPyV) DNA detection was designed, and blood samples from kidney transplant recipients and healthy individuals were screened. TSPyV-DNA was not detected in blood from healthy individuals, but 26.8% of kidney recipients presented TSPyV-DNA. This is the first report of TSPyV viremia.

Amikacin prophylaxis and risk factors for surgical site infection after kidney transplantation.

BACKGROUND: Antibiotic prophylaxis plays a major role in preventing surgical site infections (SSIs). This study aimed to evaluate antibiotic prophylaxis in kidney transplantation and identify risk factors for SSIs. METHODS: We evaluated all kidney transplantation recipients from January 2009 and December 2012. We excluded patients who died within the first 72 hr after transplantation, were undergoing simultaneous transplantation of another organ, or were below 12 years of age. The main outcome measure was SSI during the first 60 days after transplantation. RESULTS: A total of 819 kidney transplants recipients were evaluated, 65% of whom received a deceased-donor kidney. The antibiotics used as prophylaxis included cephalosporin, in 576 (70%) cases, and amikacin, in 233 (28%). We identified SSIs in 106 cases (13%), the causative agent being identified in 72 (68%). Among the isolated bacteria, infections caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae predominated. Multivariate analysis revealed that the risk factors for post-kidney transplantation SSIs were deceased donor, thin ureters at kidney transplantation, antithymocyte globulin induction therapy, blood transfusion at the transplantation procedure, high body mass index, and diabetes mellitus. The only factor associated with a reduction in the incidence of SSIs was amikacin use as antibiotic prophylaxis. Factors associated with reduced graft survival were: intraoperative blood transfusions, reoperation, human leukocyte antigen mismatch, use of nonstandard immunosuppression therapy, deceased donor, post-kidney transplantation SSIs, and delayed graft function. CONCLUSION: Amikacin prophylaxis is a useful strategy for preventing SSIs.

Rapid detection of trichodysplasia spinulosa-associated polyomavirus in skin biopsy specimen.

Trichodysplasia spinulosa-associated polyomavirus (TSV) is responsible for a rare skin cancer. Using metagenomic approaches, we determined the complete genome sequence of a TSV first detected in Brazil in spicules of an immunocompromised patient suspected to have trichodysplasia spinulosa.

Infection related to implantable central venous access devices in cancer patients: epidemiology and risk factors.

OBJECTIVE: To describe the epidemiology of infections related to the use of implantable central venous access devices (CVADs) in cancer patients and to evaluate measures aimed at reducing the rates of such infections. DESIGN: Prospective cohort study. SETTING: Referral hospital for cancer in São Paulo, Brazil. PATIENTS: We prospectively evaluated all implantable CVADs employed between January 2009 and December 2011. Inpatients and outpatients were followed until catheter removal, transfer to another facility, or death. METHODS: Outcome measures were bloodstream infection and pocket infection. We also evaluated the effects that the creation of a multidisciplinary team for CVAD care, avoiding in-hospital implantation of CVADs, and limiting CVAD insertion in neutropenic patients have on the rates of such infections. RESULTS: During the study period, 966 CVADs (mostly venous ports) were implanted in 933 patients, for a combined total of 243,792 catheter-days. We identified 184 episodes of infection: 154 (84%) were bloodstream infections, 21 (11%) were pocket infections, and 9 (5%) were surgical site infections. During the study period, the rate of CVAD-related infection dropped from 2.2 to 0.24 per 1,000 catheter-days ([Formula: see text]). Multivariate analysis revealed that relevant risk factors for such infection include surgical reintervention, implantation in a neutropenic patient, in-hospital implantation, use of a cuffed catheter, and nonchemotherapy indication for catheter use. CONCLUSIONS: Establishing a multidisciplinary team specifically focused on CVAD care, together with systematic reporting of infections, appears to reduce the rates of infection related to the use of these devices.

Clinical features and outcomes of tuberculosis in kidney transplant recipients in Brazil: a report of the last decade.

BACKGROUND: Among kidney transplant recipients (KTRs), tuberculosis is one of the most common opportunistic infections and is associated with high morbidity and mortality. The aim of this study was to describe the incidence, clinical features, and prognosis of tuberculosis in KTRs. METHODS: Retrospective single-center observational study involving all cases of tuberculosis in KTRs between 2000 and 2010. RESULTS: Of the 1549 KTRs evaluated, 43 (2.8%) developed tuberculosis, translating to an annual incidence of 803 cases/100 000 patients, considerably higher than that reported for the general population of Brazil. The median time to tuberculosis (TB) onset after transplantation was 196 d (range, 19-3626 d). Of the KTRs with tuberculosis, 67% became infected within the first year post-transplant, 74% had pulmonary tuberculosis, and 7% had a previous history of active tuberculosis. No tuberculosis prophylaxis was employed before or after transplantation. The most common symptoms were fever (in 79%), cough (in 35%), and dyspnea (in 16%). The median time from the onset of symptoms to the start of treatment was 28 d. The median duration of antituberculosis therapy was 196 d. In 15 patients (35%), the immunosuppressive therapy was reduced, and the incidence of acute rejection was higher in patients with tuberculosis than in those without (44% vs. 28%). Mortality during tuberculosis treatment was 12% (5 cases), and all five deaths were attributed to tuberculosis. Ten-yr death-censored graft survival and patient survival were similar between patients with tuberculosis and those without. CONCLUSION: Among KTRs, symptoms of tuberculosis are often attenuated, which leads to delayed diagnosis, and tuberculosis-related mortality remains high.