Utility of echocardiogram in neutropenic patients with gram positive bacteremia - a retrospective study.

INTRODUCTION: Hemato-oncology patients are vulnerable to bloodstream infections due to immunocompromised state and use of intravascular catheters. Data regarding risk of infective endocarditis (IE) among those with gram positive bacteremia is limited. We aimed to evaluate the incidence of IE among neutropenic hemato-oncology patients, and to explore the yield of echocardiogram in this population. METHODS: we conducted a single retrospective study of all hospitalized hemato-oncology neutropenic patients with gram positive blood cultures between 2007 and 2021. Data regarding Patients' characteristics, blood cultures and echocardiogram was collected. RESULTS: Study included 241 patients, with 283 isolates. Coagulase negative staphylococcus (CONS) were the most commonly isolates found, followed by streptococcus viridans. Trans thoracic echocardiography (TTE) was performed in 45% of patients overall, of which 5.8% had additional Trans esophageal echocardiogram (TEE). Only a single case of IE was identified; 47 y/o multiple myeloma patient with neutropenic fever, streptococcus viridans bacteremia, and stroke caused by septic emboli. TTE and TEE failed to demonstrate valvular pathology consistent with IE. Conclusion In our experience, the yield of echocardiogram in hemato-oncological neutropenic patients with bacteremia is extremely low, owing to reduced probability of IE in this population, and thus could be avoided in most cases.

Nationwide Outbreak of Candida auris Infections Driven by COVID-19 Hospitalizations, Israel, 2021-2022

We report an outbreak of Candida auris across multiple healthcare facilities in Israel. For the period of May 2014-May 2022, a total of 209 patients with C. auris infection or colonization were identified. The C. auris incidence rate increased 30-fold in 2021 (p = 0.00015), corresponding in time with surges of COVID-19-related hospitalization. Multilocus sequence typing revealed hospital-level outbreaks with distinct clones. A clade III clone, imported into Israel in 2016, accounted for 48.8% of typed isolates after January 2021 and was more frequently resistant to fluconazole (100% vs. 63%; p = 0.00017) and voriconazole (74% vs. 5.2%; p<0.0001) than were non-clade III isolates. A total of 23% of patients had COVID-19, and 78% received mechanical ventilation. At the hospital level, outbreaks initially involved mechanically ventilated patients in specialized COVID-19 units and then spread sequentially to ventilated non-COVID-19 patients and nonventilated patients.

Lower Serologic Response to COVID-19 mRNA Vaccine in Patients With Inflammatory Bowel Diseases Treated With Anti-TNFα.

BACKGROUND & AIM: Patients with inflammatory bowel diseases (IBD), specifically those treated with anti-tumor necrosis factor (TNF)α biologics, are at high risk for vaccine-preventable infections. Their ability to mount adequate vaccine responses is unclear. The aim of the study was to assess serologic responses to messenger RNA-Coronavirus Disease 2019 vaccine, and safety profile, in patients with IBD stratified according to therapy, compared with healthy controls (HCs). METHODS: Prospective, controlled, multicenter Israeli study. Subjects enrolled received 2 BNT162b2 (Pfizer/BioNTech) doses. Anti-spike antibody levels and functional activity, anti-TNFα levels and adverse events (AEs) were detected longitudinally. RESULTS: Overall, 258 subjects: 185 IBD (67 treated with anti-TNFα, 118 non-anti-TNFα), and 73 HCs. After the first vaccine dose, all HCs were seropositive, whereas ∼7% of patients with IBD, regardless of treatment, remained seronegative. After the second dose, all subjects were seropositive, however anti-spike levels were significantly lower in anti-TNFα treated compared with non-anti-TNFα treated patients, and HCs (both P < .001). Neutralizing and inhibitory functions were both lower in anti-TNFα treated compared with non-anti-TNFα treated patients, and HCs (P < .03; P < .0001, respectively). Anti-TNFα drug levels and vaccine responses did not affect anti-spike levels. Infection rate (∼2%) and AEs were comparable in all groups. IBD activity was unaffected by BNT162b2. CONCLUSIONS: In this prospective study in patients with IBD stratified according to treatment, all patients mounted serologic response to 2 doses of BNT162b2; however, its magnitude was significantly lower in patients treated with anti-TNFα, regardless of administration timing and drug levels. Vaccine was safe. As vaccine serologic response longevity in this group may be limited, vaccine booster dose should be considered.

Phenotypic and genotypic analysis of antimicrobial resistance in Nocardia species.

BACKGROUND: Antimicrobial resistance is common in Nocardia species but data regarding the molecular mechanisms beyond their resistance traits are limited. Our study aimed to determine the species distribution, the antimicrobial susceptibility profiles, and investigate the associations between the resistance traits and their genotypic determinants. METHODS: The study included 138 clinical strains of Nocardia from nine Israeli microbiology laboratories. MIC values of 12 antimicrobial agents were determined using broth microdilution. WGS was performed on 129 isolates of the eight predominant species. Bioinformatic analysis included phylogeny and determination of antimicrobial resistance genes and mutations. RESULTS: Among the isolates, Nocardia cyriacigeorgica was the most common species (36%), followed by Nocardia farcinica (16%), Nocardia wallacei (13%), Nocardia abscessus (9%) and Nocardia brasiliensis (8%). Linezolid was active against all isolates, followed by trimethoprim/sulfamethoxazole (93%) and amikacin (91%). Resistance to other antibiotics was species-specific, often associated with the presence of resistance genes or mutations: (1) aph(2″) in N. farcinica and N. wallacei (resistance to tobramycin); (ii) blaAST-1 in N. cyriacigeorgica and Nocardia neocaledoniensis (resistance to amoxicillin/clavulanate); (iii) blaFAR-1 in N. farcinica (resistance to ceftriaxone); (iv) Ser83Ala substitution in the gyrA gene in four species (resistance to ciprofloxacin); and (v) the 16S rRNA m1A1408 methyltransferase in N. wallacei isolates (correlating with amikacin resistance). CONCLUSIONS: Our study provides a comprehensive understanding of Nocardia species diversity, antibiotic resistance patterns, and the molecular basis of antimicrobial resistance. Resistance appears to follow species-related patterns, suggesting a lesser role for de novo evolution or transmission of antimicrobial resistance.

Outcomes of neutropenic hemato-oncological patients with viridans group streptococci (VGS) bloodstream infection based on penicillin susceptibility.

Viridans group streptococci (VGS) bloodstream infection (BSI) in neutropenic patients can be a severe complication. A higher prevalence of vancomycin use has been reported due to reduced susceptibility to penicillin. We aimed to assess the impact on mortality of both penicillin minimal inhibitory concentration (MIC) and the use of vancomycin. We conducted a retrospective multicenter study including consecutive neutropenic patients with VGS BSI between 2007 and 2019. Univariable and multivariable analyses were conducted to evaluate risk factors for mortality, including penicillin susceptibility as an independent variable. Non-susceptibility to penicillin was defined as MIC ≥ 0.25. We included 125 neutropenic patients with VGS BSI. Mean age was 53 years and ~ 50% were women. Overall, 30-day mortality rate was 25/125 (20%), and 41 patients (33%) had a VGS isolate non-susceptible to penicillin. In univariable analysis, no significant association was demonstrated between penicillin non-susceptibility and mortality (9/25, 26% vs. 32/100, 32%, p = 0.81). Among patients with a non-susceptible strain, the use of vancomycin was not significantly associated with mortality (empirical, p = 0.103, or definitive therapy, p = 0.491). Factors significantly associated with increased mortality in multivariable analysis included functional status (ECOG > 1, adjusted odds ratio [aOR] 12.53, 95% CI 3.64-43.14; p < 0.0001); allogeneic transplantation (aOR 6.33, 95% CI 1.96-20.46; p = 0.002); and co-pathogen in blood cultures (aOR 3.99, 95% CI 1.34-11.89; p = 0.013). Among neutropenic hemato-oncological patients with VGS BSI, penicillin non-susceptibility and the use of vancomycin were not associated with mortality. Thus, vancomycin should not be used routinely as empirical therapy in neutropenic patients with suspected VGS BSI.

Preceding Clinical Events in High-risk, Postoperative, Pediatric Cardiac Patients-A Novel Association With Bacteremia.

Objective: Blood stream infections (BSIs) are well described in pediatric cardiac intensive care units (PCICU). We noted that postoperative high-risk patients may develop BSI after a preceding clinical event (PCE). The study aim was to investigate whether high-risk patients who developed bacteremia experienced more PCEs than a similar group of high-risk patients. Design: Retrospective case-control study. Setting: Referral pediatric center. Patients: We enrolled patients who developed bacteremia from March 2010 to November 2019, after undergoing open-heart surgery at a pediatric center. The control group was comprised of case-matched patients with immediate consecutive same surgery. Interventions: None. Measurements: We recorded operative data, common risk factors, postoperative indicators of organ dysfunction, mortality, and PCEs 72 to 24 h before bacteremia emerged. Main results: A total of 200 patients were included (100 with bacteremia and 100 controls). Key demographic and operative parameters were matched. Bacteremia emerged on average on postoperative day 12.8. Skin-associated Gram-positive bacteria were cultured in 10% and Gram-negative bacteria in 84% of the patients. Average central-venous lines (CVL) duration was 9.5 ± 8.4 days. Postoperatively (72 h), indicators of organ dysfunction were significantly worse in patients with bacteremia, with a higher rate of postoperative complications during PCICU length-of-stay (LOS). In the bacteremia group, 72 to 24 h prior to the development of bacteremia, 92 (92%) PCEs were recorded, as compared to 21 (21%) in controls during their entire LOS (odds ratio [OR] 43.3, confidence interval [CI] 18.2-103.1, P < .0001). Conclusions: We propose a 3-hit model demonstrating that high-risk patients undergoing open-heart surgery have significantly higher risk for bacteremia after a PCE.

Clinical impact of biofire gastrointestinal panel testing for hospitalised children with acute gastroenteritis.

AIM: To investigate the clinical impact of BioFire FilmArray Gastrointestinal Panel (FGP) testing in real-life diarrhoeal episodes of hospitalised paediatric patients. METHODS: Children hospitalised between October 2018 and September 2020 for whom stool specimens for FGP were submitted at the clinician's discretion were retrospectively observed. For each episode, demographics, clinical information and stool tests were collected. RESULTS: The clinical impact for each case was evaluated by changing the antibiotic prescription, following the result of the FGP testing. Out of 140 diarrhoeal episodes, 25 pathogens were found in 24 cases using conventional methods, whereas, FGP testing identified 75 pathogens in 56 cases (p < 0.05). The pathogens more frequently identified by FGP testing were Campylobacter, Shigella, Rotavirus, Giardia lamblia and Cryptosporidium. The clinical impact of FGP testing was observed in 17/140 (12%) diarrhoeal episodes, and higher rates in previously healthy (19%) and solid organ-transplanted children (15%). CONCLUSION: We found that using FGP testing for hospitalised children with diarrhoeal episodes could increase pathogen identification and impact clinical decisions, especially in healthy and transplant patients.

Clinical Outcomes of Hospitalized Patients with SARS-CoV-2 Omicron Variant vs. Influenza A During Influenza Season 2021 to 2022: A Retrospective Observational Study.

BACKGROUND: Influenza and coronavirus disease 2019 (COVID-19) are respiratory diseases with similar modes of transmission. In December 2021, influenza re-emerged after it had been undetected since March 2020 and the Omicron variant replaced the Delta variant. Data directly comparing the two diseases are scarce. OBJECTIVES: To compare the outcomes of patients with both the Omicron variant and influenza during 2021-2022. METHODS: We performed a retrospective study conducted in Beilinson hospital, Israel, from December 2021 to January 2022. We included all hospitalized patients with either laboratory-confirmed COVID-19 or influenza. The primary outcome was 30-day mortality. RESULTS: We identified 167 patients diagnosed with Omicron and 221 diagnosed with Influenza A. The median age was 71 years for Omicron and 65 years for influenza. Patients with Omicron had a significantly higher Charlson Comorbidity Index score (4 vs. 3, P < 0.001). Patients with Omicron developed more respiratory failure that needed mechanical ventilation (7% vs. 2%, P = 0.05) and vasopressors (14% vs. 2%, P < 0.001) than patients with influenza. In a multivariate model, 30-day mortality was lower in patients diagnosed with influenza than in patients diagnosed with Omicron (19/221 [9%] vs. 44/167 [26%], hazard ratio 0.45, 95% confidence interval 0.25-0.81). CONCLUSIONS: Patients diagnosed with Omicron had higher mortality than patients diagnosed with seasonal influenza. This finding could be due to differences in co-morbidities, the virus pathogenicity, and host responses to infection.

Humoral serological response to the BNT162b2 vaccine is abrogated in lymphoma patients within the first 12 months following treatment with anti-CD2O antibodies.

Patients with lymphoma, especially those treated with anti-CD20 monoclonal antibodies, suffer high COVID-19-associated morbidity and mortality. The goal of this study was to assess the ability of lymphoma patients to generate a sufficient humoral response after two injections of BNT162b2 Pfizer vaccine and to identify factors influencing the response. Antibody titers were measured with the SARS-CoV-2 IgG II Quant (Abbott ) assay in blood samples drawn from lymphoma patients 4 2 weeks after the second dose of vaccine. The cutoff for a positive response was set at 50 AU/mL. Positive serological responses were observed in 51% of the 162 patients enrolled in this cross-sectional study. In a multivariate analysis, an interval of <12 months between the last anti-CD20 monoclonal antibody dose and the second vaccine dose (odds ratio=31.3 [95% confidence interval: 8.4-116.9], P<0.001) and presence of active lymphoma (odds ratio=4.2 (95% confidence interval: 2.1- 8.2), P=0.006) were identified as negative response predictors. The rate of seropositivity increased from 3% in patients vaccinated within 45 days after the last monoclonal antibody administration to 80% in patients vaccinated >1 year after this therapy. The latter percentage was equal to that of patients never exposed to monoclonal antibodies. In conclusion, lymphoma patients, especially those recently treated with anti- CD20 monoclonal antibodies, fail to develop sufficient humoral response to BNT162b2 vaccine. While a serological response is not the only predictor of immunity, its low level could make this population more vulnerable to COVID-19, which implies the need for a different vaccination schedule for such patients.

Humoral response among patients with interstitial lung disease vaccinated with the BNT162b2 SARS-Cov-2 vaccine: a prospective cohort study.

BACKGROUND: Patients with interstitial lung disease (ILD) are at high risk of severe COVID-19 infection. Additionally, their anti-inflammatory and antifibrotic treatment may cause immunosuppression. Nevertheless, their ability to mount an adequate immune response to messenger RNA SARS-CoV-2 vaccines was not evaluated. Therefore, we aimed to evaluate the humoral response after the BNT162b2 vaccine among idiopathic pulmonary fibrosis (IPF) patients treated with antifibrotic therapy and among non-IPF ILD patients treated with anti-inflammatory therapy. METHODS: We conducted an observational prospective cohort study to evaluate the level of anti-spike (S-IgG) antibodies after two doses of the BNT162b2 vaccine in patients with ILD. The cohort included 40 patients with idiopathic pulmonary fibrosis (IPF) treated with anti-fibrotic therapy and 29 patients with non-IPF ILD treated with anti-inflammatory therapy. For S-IgG titer measurement, one serology test was drawn from all patients 4-6 months after the second vaccine dose. In addition a control group matched for age and sex was created from a healthy control cohort of 107 patients. The study was conducted in Rabin Medical Center (Israel) between June and August 2021. RESULTS: All patients in the anti-fibrotic arm were seropositive (40/40), corresponding to the matched control group (P = 1.0). The anti-fibrotic arm had a significantly lower median antibody titer in comparison to the matched control group (361.10 [IQR, 207-811] AU/ml vs. 820.75 [IQR, 459-1313] AU/ml; P < 0.001). Only 48.3% (14/29) of patients in the anti-inflammatory arm were seropositive in comparison to 100% (29/29) in the healthy control group (P < 0.001). The anti-inflammatory arm had a significantly lower median antibody titer in comparison to the healthy control group (39.6 [IQR, 4.25-165] AU/ml vs. 970.1 [IQR, 505-1926] AU/ml; P < 0.001). CONCLUSION: IPF patients treated with antifibrotic therapy mount an adequate immune response after 2 doses of the BNT162b2 vaccine, and maintain a 100% seropositivity rate 4-6 months after vaccination. However, their antibody titer was reduced in comparison to a healthy control group. Among patients with non-IPF ILD treated with anti-inflammatory therapy, 48% were seronegative 4-6 months after the second vaccine dose. Moreover, treatment with rituximab caused significant immunosuppression, even in comparison to other anti-inflammatory treatments.

Immune Response to Third Dose BNT162b2 COVID-19 Vaccine Among Kidney Transplant Recipients-A Prospective Study.

Immune response to two SARS-CoV-2 mRNA vaccine doses among kidney transplant recipients (KTRs) is limited. We aimed to evaluate humoral and cellular response to a third BNT162b2 dose. In this prospective study, 190 KTRs were evaluated before and ∼3 weeks after the third vaccine dose. The primary outcomes were anti-spike antibody level >4160 AU/ml (neutralization-associated cutoff) and any seropositivity. Univariate and multivariate analyses were conducted to identify variables associated with antibody response. T-cell response was evaluated in a subset of participants. Results were compared to a control group of 56 healthcare workers. Among KTRs, we found a seropositivity rate of 70% (133/190) after the third dose (37%, 70/190, after the second vaccine dose); and 27% (52/190) achieved levels above 4160 AU/ml after the third dose, compared to 93% of controls. Variables associated with antibody response included higher antibody levels after the second dose (odds ratio [OR] 30.8 per log AU/ml, 95% confidence interval [CI]11-86.4, p < 0.001); and discontinuation of antimetabolite prior to vaccination (OR 9.1,95% CI 1.8-46.5, p = 0.008). T-cell response was demonstrated in 13% (7/53). In conclusion, third dose BNT162b2 improved immune response among KTRs, however 30% still remained seronegative. Pre-vaccination temporary immunosuppression reduction improved antibody response.

Definitive antibiotic treatment with a third-generation cephalosporin and with piperacillin-tazobactam worked well for some children with Serratia bacteraemia.

AIM: This study aimed to describe epidemiological and clinical characteristics of Serratia bacteraemia and to identify factors associated with mortality. METHODS: The microbiology database of Schneider Children's Medical Centre of Israel was examined for Serratia marcescens positive blood cultures, between January 2007 and May 2020. Demographic, clinical and microbial characteristics were analysed. RESULTS: Of the 81 patients files that met the inclusion criteria, 64 (80%) were of patients hospitalised in paediatric intensive care units. The median age was 78 days and 54% were male. In-hospitalisation mortality was 26%, 62% died under 90 days old. Underlying conditions including prematurity, congenital cardiac defects and malignancies were noted in 95% of patients. Prior to the bloodstream infections, 62% of patients underwent procedures, 64% were on ventilatory support and 77% had central lines. Thrombocytopenia and elevated C-reactive protein levels were found in 60% of the children. Twenty-eight children received definitive monotherapy as either piperacillin-tazobactam or a third-generation cephalosporin; survival rates were similar between the two antibiotic treatment groups. CONCLUSION: In our cohort, 26% died. Death was more common in young infants. Mortality was associated with hospitalisation in intensive care units and thrombocytopenia. Survival rates following definitive monotherapy were similar for patients treated with piperacillin-tazobactam and those treated with third-generation cephalosporin.

Adenovirus can be a serious, life-threatening disease, even in previously healthy children.

AIM: Adenovirus infections are exceedingly common in childhood. However, little is known of the clinical characteristics of children admitted with severe infection to the paediatric intensive care unit (PICU). METHODS: Clinical data on children hospitalised with adenovirus infection between January 2005 and March 2020 were collected. We compared data between children hospitalised in the PICU and those who were not in a 1:2 ratio. RESULTS: During the study period, 69 children with adenovirus infection were admitted to the PICU, representing 5% of all hospitalised children with adenovirus. Thirty-four (49%) were previously healthy children. Mortality occurred in 5 patients, and all had an underlying illness. Cidofovir was used in 21 children, including 11 who were previously healthy. No side effects were attributed to the treatment. During 2005-2014, viral co-infection rates were 42% in the PICU group and 11% in the control group (p = 0.002). However, during 2015-2020, when the viral panel became widespread in our institution, the rates of co-infection were similar in the two groups (32% and 34%, p = 1.0). CONCLUSION: Our findings suggest that adenovirus may present as a serious, life-threatening disease even in previously healthy children.

Does accepted definition of Clostridioides difficile infection (CDI) severity predict poor outcomes in older adults?

BACKGROUND: Advanced age is an important factor affecting Clostridioides difficile infection (CDI) risk and outcome. While fever and leukocytosis are prominent findings in young individuals with CDI, they are usually blunted in the elderly. Furthermore, chronic kidney disease often exists among this population prior to the CDI episode onset. AIM: We aimed to examine whether the accepted definition of severe CDI (leukocytosis ≥ 15,000 cells/µl or serum creatinine > 1.5 mg/dl) predicts poor outcomes in the elderly. METHODS: All CDI hospitalized individuals between January-2013 and May-2020 were included. The study population was dichotomized into older group (≥ 65 years) and younger group (< 65 years). Primary composite outcome was 30-day mortality, colectomy due to severe colitis, or intensive care unit admission. The older group was divided according to the primary outcome to evaluate the effect of CDI severity criteria. RESULTS: The study included 853 patients. Of them, 571 were in the older group and 282 in the younger one. The primary outcome was significantly more common in the older group (93/571, 16% vs. 31/282, 11%; p = 0.04). Ninety days mortality was significantly higher in the older group [116/571, 20% vs. 30/282, 11%; p < 0.01]. In multivariate analysis, accepted CDI severity criteria were not significantly associated with poor outcomes (odds ratio [OR] = 1.2, 95% confidence interval [CI] 0.7-2.2, p = 0.5). Advanced dementia and low serum albumin were significant predictors of poor outcomes (OR = 3, 95%CI 1.5-6, p = 0.002 and OR = 3.1, 95%CI 1.7-5.8, p < 0.01). CONCLUSION: The accepted definition of CDI severity was not useful in predicting CDI poor outcomes in older adults. In this population, we suggest advanced dementia and low albumin among others as CDI severity markers.

Clinical Features and Comparison of Kingella and Non-Kingella Endocarditis in Children, Israel.

Kingella spp. have emerged as an important cause of invasive pediatric diseases. Data on Kingella infective endocarditis (KIE) in children are scarce. We compared the clinical features of pediatric KIE cases with those of Streptococcus species IE (StIE) and Staphylococcus aureus IE (SaIE). A total of 60 patients were included in the study. Throughout the study period, a rise in incidence of KIE was noted. KIE patients were significantly younger than those with StIE and SaIE, were predominately boys, and had higher temperature at admission, history of oral aphthae before IE diagnosis, and higher lymphocyte count (p<0.05). Pediatric KIE exhibits unique features compared with StIE and SaIE. Therefore, in young healthy children <36 months of age, especially boys, with or without a congenital heart defect, with a recent history of oral aphthae, and experiencing signs and symptoms compatible with endocarditis, Kingella should be suspected as the causative pathogen.

The impact of obesity on seasonal influenza: a single-center, retrospective study conducted in Israel.

Obesity is associated with an increased susceptibility to infections. Several studies have reported adverse clinical outcomes of influenza among obese individuals. Our aim was to examine the association between obesity and the clinical outcomes of hospitalized adult patients ill with seasonal influenza. Consecutive hospitalized adult patients between 10/2017 and 4/2018 with laboratory confirmed influenza A and B were divided into an obese group (body mass index (BMI) ≥ 30 kg/m2) and controls. The primary outcome was a composite endpoint of 30-day all-cause mortality, vasopressor use, mechanical ventilation, ICU admission, and severe influenza complication (myocarditis and encephalitis). Secondary outcomes encompassed all the components of the primary outcome, 90-day all-cause mortality, occurrence of pneumonia, length of hospital stay, and 90-day readmission rates. The study comprised 512 hospitalized adults diagnosed with laboratory-confirmed influenza A (195/512) and B (317/512). Within this group, 17% (86/512) were classified obese; the remaining 83% (426/512) were controls. Results of the composite outcome (7/85, 8% vs. 45/422, 11%; p=0.5) and the crude 30-day all-cause mortality rate (5/86, 6% vs. 34/426, 8%, p=0.5) were similar between the two groups. The multivariate analysis demonstrated that obesity was not a significant risk factor for influenza adverse events (OR=1.3, CI 95% 0.3-3.3; p=0.5), whereas advanced age, chronic kidney disease, and hypoalbuminemia were significant risk factors (OR=1.03, OR=2.7, and OR=5.4, respectively). Obesity was not associated with influenza-related morbidity and mortality among the hospitalized adults during the 2017-2018 influenza season. Further studies researching different influenza seasons are essential.

Excluded versus included patients in a randomized controlled trial of infections caused by carbapenem-resistant Gram-negative bacteria: relevance to external validity.

BACKGROUND: Population external validity is the extent to which an experimental study results can be generalized from a specific sample to a defined population. In order to apply the results of a study, we should be able to assess its population external validity. We performed an investigator-initiated randomized controlled trial (RCT) (AIDA study), which compared colistin-meropenem combination therapy to colistin monotherapy in the treatment of patients infected with carbapenem-resistant Gram-negative bacteria. In order to examine the study's population external validity and to substantiate the use of AIDA study results in clinical practice, we performed a concomitant observational trial. METHODS: The study was conducted between October 1st, 2013 and January 31st, 2017 (during the RCTs recruitment period) in Greece, Israel and Italy. Patients included in the observational arm of the study have fulfilled clinical and microbiological inclusion criteria but were excluded from the RCT due to receipt of colistin for > 96 h, refusal to participate, or prior inclusion in the RCT. Non-randomized cases were compared to randomized patients. The primary outcome was clinical failure at 14 days of infection onset. RESULTS: Analysis included 701 patients. Patients were infected mainly with Acinetobacter baumannii [78.2% (548/701)]. The most common reason for exclusion was refusal to participate [62% (183/295)]. Non-randomized and randomized patients were similar in most of the demographic and background parameters, though randomized patients showed minor differences towards a more severe infection. Combination therapy was less common in non-randomized patients [31.9% (53/166) vs. 51.2% (208/406), p = 0.000]. Randomized patients received longer treatment of colistin [13 days (IQR 10-16) vs. 8.5 days (IQR 0-15), p = 0.000]. Univariate analysis showed that non-randomized patients were more inclined to clinical failure on day 14 from infection onset [82% (242/295) vs. 75.5% (307/406), p = 0.042]. After adjusting for other variables, non-inclusion was not an independent risk factor for clinical failure at day 14. CONCLUSION: The similarity between the observational arm and RCT patients has strengthened our confidence in the population external validity of the AIDA trial. Adding an observational arm to intervention studies can help increase the population external validity and improve implementation of study results in clinical practice. TRIAL REGISTRATION: The trial was registered with ClinicalTrials.gov, number NCT01732250 on November 22, 2012.

Short versus prolonged antibiotic treatment for complicated urinary tract infection after kidney transplantation.

There is no consensus regarding the optimal duration of antibiotic therapy for urinary tract infection (UTI) following kidney transplantation (KT). We performed a retrospective study comparing short (6-10 days) versus prolonged (11-21 days) antibiotic therapy for complicated UTI among KT recipients. Univariate and inverse probability treatment weighted (IPTW) adjusted multivariate analysis for composite primary outcome of all-cause mortality or readmissions within 30 days and relapsed UTI 180 days were performed. Overall, 214 KT recipients with complicated UTI were included; 115 short-course treatment (median 8, interquartile range [IQR] 6-9 days), 99 prolonged course (median 14, IQR 12-21 days). The composite outcome occurred in 33 (28.6%) in the short-course group and 30 (30%) in the prolonged-course group; relapsed UTI occurred in 19 (16.5%) vs. 21 (21%), respectively. Duration of antibiotic treatment was not associated with any of these outcomes. The only risk factor for mortality/readmissions in multivariate analysis was deceased donor. No differences between groups were demonstrated for length of hospital stay, rates of bacteraemia, resistance development, and serum creatinine at 30 and 90 days. In conclusion, we found no difference in clinical outcomes between KT recipients treated for complicated UTI with short-course antibiotic (6-10 days) versus longer course (11-21 days).

The significance of acute kidney injury in Clostridioides difficile infection.

OBJECTIVE: Clostridioides difficile infection (CDI) may present as sepsis with acute kidney injury (AKI). Herein, we aimed to evaluate the clinical outcomes of patients with AKI complicating CDI. METHODS: All consecutive adult patients hospitalized in Rabin Medical Center between 1 January 2013 and 31 December 2018 with laboratory confirmed CDI, were included in the study. Subjects were divided into two groups: patients with AKI and controls. Primary outcome was all-cause mortality at 30 days after the CDI episode. Secondary outcomes included number of patients with deteriorating renal functions at 90 days, 90-day all-cause mortality, length of hospital stay and readmission rates. A multivariable analysis adjusted for other risk factors for mortality and renal function deterioration was conducted. An analysis of subgroups based on baseline kidney function and AKI stage was also performed. Results are reported as odds ratios (OR) with 95% confidence intervals (95% CI). RESULTS: A total of 527 patients were included, amongst them 140 patients with AKI and 387 controls. Patients with AKI were significantly older, had more comorbidities, and more of them had chronic kidney disease (CKD) at any stage at baseline. On multivariable analysis, 30 days all-cause mortality was significantly higher in patients with AKI, OR 1.67, 95% CI 1.05-2.66. Mortality was also significantly associated with advanced age and baseline CKD. Among patients alive at 90 days, deterioration of renal function was significantly more common in patients with AKI (27/63 (42.8%) vs 22/191 (11.5%), P = .000). In a multivariable analysis, deterioration of renal function at 90 days was associated with AKI at presentation (OR 4.67, 95% CI 1.05-20.6). Early (at discharge) renal function recovery was not associated with protection from further deterioration of renal function at day 90. CONCLUSIONS: CDI patients with AKI have an increased risk of mortality and further deterioration of renal function. Early renal function recovery does not infer protection from further deterioration of renal function at 3 months. Caution and nephrology follow-up should be considered after discharge for all patients who developed AKI during CDI, regardless of discharge creatinine levels.

Adenovirus Infection in Children with Down Syndrome.

BACKGROUND: Adenovirus infections are prevalent in children. They usually cause a mild self-limited disease. However, this infection can be associated with considerable morbidity and mortality in specific populations, especially among immunocompromised children. Children with Down syndrome are susceptible to a higher frequency and increased severity of viral infections. Little is known about the severity and clinical course of adenovirus infections in children with Down syndrome. OBJECTIVES: To characterize hospitalized children diagnosed with Down syndrome and presenting with adenovirus infection. METHODS: We performed a retrospective review of children admitted with adenovirus from January 2005 to August 2014 from a single tertiary pediatric medical center in Israel. Data were compared between patients with and without Down syndrome. RESULTS: Among the 486 hospitalized children with adenoviral infection, 11 (2.28%) were diagnosed with Down syndrome. We found that children with Down syndrome were more likely to experience a higher incidence of complications (18.2% vs. 2.4%, P = 0.008), a higher rate of admissions to the intensive care unit (36.4% vs. 2.4%, P < 0.001), and more prolonged hospitalizations (17 ± 15.9 days compared to 4.46 ± 3.16, P = 0.025). CONCLUSIONS: Children with Down syndrome who were hospitalized with adenovirus infection represent a high-risk group and warrant close monitoring. If a vaccine for adenovirus becomes available, children with Down syndrome should be considered as candidates.