Survey on the approach to antibiotic prophylaxis in liver and kidney transplant recipients colonized with "difficult to treat" Gram-negative bacteria

BACKGROUND

Performance of active screening for multidrug-resistant Gram-negative bacteria (MDR-GNB) and administration of targeted antibiotic prophylaxis (TAP) in colonized patients undergoing liver (LT) and/or kidney transplantation (KT) are controversial issues.

METHODS

Self-administered electronic cross-sectional survey disseminated from January to February 2022. Questionnaire consisted of four parts: hospital/transplant program characteristics, standard screening and antibiotic prophylaxis, clinical vignettes asking for TAP in patients undergoing LT and KT with prior infection/colonization with four different MDR-GNB (extended-spectrum cephalosporin-resistant Enterobacterales [ESCR-E], carbapenem-resistant Enterobacterales [CRE], multidrug-resistant Pseudomonas aeruginosa [MDR-Pa], and carbapenem-resistant Acinetobacter baumannii [CRAb]).

RESULTS

Fifty-five respondents participated from 14 countries, mostly infectious disease specialists (69%) with active transplant programs (>100 procedures/year for 34.5% KT and 23.6% LT), and heterogeneous local MDR-GNB prevalence from <15% (30.9%), 15%-30% (43.6%) to >30% (16.4%). The frequency of screening for ESCR-E, CRE, MDR-Pa, and CRAb was 22%, 54%, 17%, and 24% for LT, respectively, and 18%, 36%, 16%, and 11% for KT. Screening time-points were mainly at transplantation 100%, only one-third following transplantation. Screening was always based on rectal swab cultures (100%); multi-site sampling was reported in 40% of KT and 35% of LT. In LT clinical cases, 84%, 58%, 84%, and 40% of respondents reported TAP for prior infection/colonization with ESCR-E, CRE, MDR-Pa, and CRAb, respectively. In KT clinical cases, 55%, 39%, 87%, and 42% of respondents reported TAP use for prior infection/colonization with ESCR-E, CRE, MDR-Pa, and CRAb, respectively.

CONCLUSION

There is a large heterogeneity in screening and management of MDR-GNB carriage in LT and KT.

Real-Time TDM-Guided Optimal Joint PK/PD Target Attainment of Continuous Infusion Piperacillin-Tazobactam Monotherapy Is an Effective Carbapenem-Sparing Strategy for Treating Non-Severe ESBL-Producing Enterobacterales Secondary Bloodstream Infections: Findings from a Prospective Pilot Study

(1) Objectives: To assess the impact of optimal joint pharmacokinetic/pharmacodynamic (PK/PD) target attainment of continuous infusion (CI) piperacillin-tazobactam monotherapy on the microbiological outcome of documented ESBL-producing Enterobacterlaes secondary bloodstream infections (BSIs). (2) Methods: Patients hospitalized in the period January 2022-October 2023, having a documented secondary BSI caused by ESBL-producing Enterobacterales, and being eligible for definitive targeted CI piperacillin-tazobactam monotherapy according to specific pre-defined inclusion criteria (i.e., absence of septic shock at onset; favorable clinical evolution in the first 48 h after starting treatment; low-intermediate risk primary infection source) were prospectively enrolled. A real-time therapeutic drug monitoring (TDM)-guided expert clinical pharmacological advice (ECPA) program was adopted for optimizing (PK/PD) target attainment of CI piperacillin-tazobactam monotherapy. Steady-state plasma concentrations (Css) of both piperacillin and tazobactam were measured, and the free fractions (f) were calculated based on theoretical protein binding. The joint PK/PD target attainment was considered optimal whenever the piperacillin fCss/MIC ratio was >4 and the tazobactam fCss/target concentration (CT) ratio was >1 (quasi-optimal or suboptimal if only one or neither of the two thresholds were achieved, respectively). Univariate analysis was carried out for assessing variables potentially associated with failure in achieving the optimal joint PK/PD target of piperacillin-tazobactam and microbiological eradication. (3) Results: Overall, 35 patients (median age 79 years; male 51.4%) were prospectively included. Secondary BSIs resulted from urinary tract infections as a primary source in 77.2% of cases. The joint PK/PD target attainment was optimal in as many as 97.1% of patients (34/35). Microbiological eradication occurred in 91.4% of cases (32/35). Attaining the quasi-optimal/suboptimal joint PK/PD target of CI piperacillin-tazobactam showed a trend toward a higher risk of microbiological failure (33.3% vs. 0.0%; p = 0.08) (4) Conclusions: Real-time TDM-guided optimal joint PK/PD target attainment of CI piperacillin-tazobactam monotherapy may represent a valuable and effective carbapenem-sparing strategy when dealing with non-severe ESBL-producing Enterobacterales secondary BSIs.

Tolerability of pulsed high-dose L-AmB as pre-emptive therapy in patients at high risk for intra-abdominal candidiasis: A phase 2 study (LAMBDA study)

BACKGROUND

Intra-abdominal candidiasis (IAC) has a high mortality rate. However, the correct management of a critically ill patient with suspected IAC remains unclear. The aim of this study was to evaluate the safety of pulsed high-dose liposomal amphotericin B (L-AmB) in patients with suspected IAC managed with a beta-D-glucan (BDG)-guided strategy.

METHODS

This phase 2 prospective study enrolled adult patients with intra-abdominal sepsis following surgery. Patients received a single dose of L-AmB 5 mg/kg on day 1. On day 3, L-AmB was discontinued in patients with a negative basal BDG result, and continued (3 mg/kg/daily) in patients with a positive basal BDG result or microbiologically confirmed IAC. The primary endpoint was the occurrence of adverse events, defined using the Common Toxicity Criteria classification.

RESULTS

In total, 40 patients were enrolled from January 2019 to August 2022. Fifteen (37.5%) patients were male, and the median age was 65 [interquartile range (IQR) 49-76] years. Thirty-one (77.5%) patients underwent urgent surgery, and the principal indication was secondary/tertiary peritonitis (n=22, 55%); half of the patients had undergone a previous surgical operation within the preceding 30 days. Five (12.5%) patients met the criteria for septic shock at enrolment. The median APACHE II score on admission to the intensive care unit was 12 (IQR 10-15). IAC was excluded in 33 (85%) patients, but IAC was probable and proven in five (12.5%) and two (5%) patients, respectively. The single dose of L-AmB 5 mg/kg was well tolerated in all patients, and no early or late severe adverse events related to the drug were reported. L-AmB was discontinued in 65% of patients following a negative basal BDG result. The all-cause 30-day mortality rate was 15%, and no deaths were related to L-AmB administration or uncontrolled IAC. The mortality rates for patients with and without proven IAC were 0% and 15.8%, respectively (P=0.99).

CONCLUSIONS

The rate of proven IAC among critically ill high-risk patients was low (5%). A single dose of L-AmB 5 mg/kg, with prompt withdrawal in the case of a basal negative BDG result, seems to be a safe and effective approach in this population.

Could an optimized joint pharmacokinetic/pharmacodynamic target attainment of continuous infusion ceftazidime-avibactam be a way to avoid the need for combo therapy in the targeted treatment of deep-seated DTR Gram-negative infections?

The objective of this study was to assess the relationship between joint pharmacokinetic/pharmacodynamic (PK/PD) target attainment of continuous infusion (CI) ceftazidime-avibactam and the microbiological outcome of documented difficult-to-treat resistant (DTR) Gram-negative infections. A 2-year retrospective cohort study was performed in patients receiving CI ceftazidime-avibactam mono- or combo therapy for documented DTR Gram-negative infections and undergoing therapeutic drug monitoring of both ceftazidime and avibactam. The free fractions of steady-state concentrations (fCss) of ceftazidime and avibactam were calculated. The joint PK/PD target was considered optimal when both the fCss/MIC ratio for ceftazidime ≥4 (equivalent to 100% fT>4xMIC) and the fCss/CT ratio for avibactam >1 (equivalent to 100% fT >CT of 4.0 mg/L) were simultaneously achieved (quasi-optimal if only one of the two and suboptimal if neither of the two was achieved). Multivariate logistic regression analysis was applied for testing potential variables associated with microbiological failure. Fifty-eight patients were treated with CI ceftazidime-avibactam mono- (36) or combo therapy (22) for documented DTR Gram-negative infections [74.2% for primary or secondary bloodstream infections (BSIs)]. Combo therapy was administered more frequently to intensive care unit (ICU) patients (P = 0.023) or for pneumonia (P = 0.001) and less frequently for intra-abdominal infections and BSIs (P = 0.04). Microbiological failure occurred in five cases (8.6%, three in mono- and two in combo therapy). In the multivariate analysis, the suboptimal/quasi-optimal joint PK/PD target emerged as the only independent predictor of microbiological failure (odds ratio [OR] 11.11; 95% confidence interval [CI] 1.31-93.98; P = 0.023), whereas monotherapy was not (P = 0.99). Optimized joint PK/PD target attainment of CI ceftazidime-avibactam monotherapy could represent a way forward for allowing microbiological eradication of DTR Gram-negative infections and could render unnecessary combo therapy.

Comparison between available early antiviral treatments in outpatients with SARS-CoV-2 infection: a real-life study

PURPOSE

To investigate the clinical impact of three available antivirals for early COVID-19 treatment in a large real-life cohort.

METHODS

Between January and October 2022 all outpatients tested positive for SARS-CoV-2 referring to IRCCS S. Orsola hospital treated with an early antiviral therapy were enrolled. A comparison between patients treated with nirmatrelvir/ritonavir (NTV/r), molnupiravir (MPV) and remdesivir (RDV) was conducted in term of indications and outcome. To account for differences between treatment groups a propensity score analysis was performed. After estimating the weights, we fitted a survey-weighted Cox regression model with inverse-probability weighting with hospital admission/death versus clinical recovery as the primary outcome.

RESULTS

Overall 1342 patients were enrolled, 775 (57.8%), 360 (26.8%) and 207 (15.4%) in MPV, NTV/r and RDV group, respectively. Median age was 73 (59-82) years, male sex was 53.4%. Primary indication was immunosuppression (438, 32.6%), the median time from symptom onset to drug administration was 3 [2-4] days. Overall, clinical recovery was reached in 96.9% of patients, with hospital admission rate of 2.6%. No significant differences were found in clinical recovery nor hospitalization. Cox regression showed a decreased probability of hospital admission/ death among prior vaccinated patients compared with unvaccinated (HR 0.31 [95%CI 0.14-0.70], p = 0.005]). No difference in hospitalization rates in early treatment compared to late treatment were found.

CONCLUSIONS

No differences among MPV, NTV/r and RDV in terms of clinical recovery or hospitalization were found. Patients not vaccinated had a significant increased risk of hospitalization.

Bloodstream Infections in Intensive Care Unit during Four Consecutive SARS-CoV-2 Pandemic Waves

Critically ill COVID-19 patients are at an increased risk of bloodstream infections (BSIs). We performed a retrospective observational single-center study on COVID-19 patients admitted to intensive care unit (ICU) to assess the incidence of BSIs in four consecutive periods: 21 February-31 July 2020 (W1), 1 August 2020-31 January 2021 (W2), 1 February-30 September 2021 (W3) and 1 October 2021 and 30 April 2022 (W4). BSIs that occurred 48 h after ICU admission were included. The crude incidence of BSIs was estimated by means of Poisson distribution normalized to 1000 patient-days. A total of 404 critically ill COVID-19 patients were admitted to ICU, of whom 284 (61%) developed at least one episode of BSI with an overall crude incidence of 87 events every 1000 patient-days (95% CI 77-98) without a significant difference in consecutive epidemic periods (p = 0.357). Gram-positive bacteria were the most frequent etiological agents of BSIs, contributing to 74.6% episodes. A progressive decrease in BSIs due to Enterococcus spp. was observed (W1 57.4%, W2 43.7%, W3 35.7% and W4 32.7%; p = 0.004). The incidence of BSIs remained stable during different epidemic periods. Enterococcus spp. prevalence was significantly reduced, although still accounted for one third of BSIs in more recent epidemic periods.

Impact on clinical outcome of follow-up blood cultures and risk factors for persistent bacteraemia in patients with gram-negative bloodstream infections: a systematic review with meta-analysis

BACKGROUND

The clinical usefulness of follow-up blood cultures (FUBCs) in gram-negative bloodstream infections (GN-BSIs) represents a debated issue.

OBJECTIVE

To assess the impact on the clinical outcome of FUBCs in patients with GN-BSI and to predict risk factors for persistent bacteraemia.

DATA SOURCES

PubMed-MEDLINE, Scopus, and the Cochrane Library Database were independently searched until 24 June, 2022.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials, prospective, or retrospective observational studies, including patients affected by GN-BSIs. Primary endpoints were in-hospital mortality rate, and persistent blood stream infections were defined as FUBC-positive for the same pathogen isolated from index blood cultures (BCs).

PARTICIPANTS

Hospitalized patients with documented GN-BSIs.

INTERVENTION

Performance of FUBCs (defined as subsequent BCs collected at least 24 hours after index BCs).

ASSESSMENT OF RISK OF BIAS

Quality of included studies was independently assessed according to the Cochrane Risk of Bias Tool and the Risk Of Bias In Non-randomized Studies of Interventions.

METHODS OF DATA SYNTHESIS

Meta-analysis was performed by pooling odds ratio (OR) retrieved from studies providing adjustment for confounders using random-effect model with the inverse variance method. Risk factors for persistent blood stream infections were also assessed.

RESULTS

A total of 3747 articles were screened, and 11 observational studies (6 assessing impact on outcome (N = 4631), and 5 investigating risk factors for persistent GN-BSI (N = 2566)), conducted between 2002 and 2020 were included. The execution of FUBCs was associated with a significantly lower risk of mortality (OR, 0.58; 95% CI, 0.49-0.70; I2 = 0.0%). The presence of end-stage renal disease (OR, 2.99; 95% CI, 1.77-5.05), central venous catheter (OR, 3.30; 95% CI, 1.82-5.95), infections due to extended-spectrum β-lactamase-producing strains (OR, 2.25; 95% CI, 1.18-4.28), resistance to empirical treatment (OR, 2.70; 95% CI, 1.65-4.41), and unfavourable response at 48 hours (OR, 2.99; 95% CI, 1.44-6.24) emerged as independent risk factors for persistent bacteraemia.

CONCLUSIONS

The execution of FUBCs is associated with a significantly low risk of mortality in patients with GN-BSIs. Our analysis could be useful to stratify patients at a high risk of persistent bacteraemia to optimize the use of FUBCs.

Validation of the INCREMENT-SOT-CPE score in a large cohort of liver transplant recipients with carbapenem-resistant Enterobacterales infection

BACKGROUND

Management of infections due to carbapenemase-resistant Enterobacterales (CRE) in solid organ transplant (SOT) recipients remains a difficult challenge. The INCREMENT-SOT-CPE score has been specifically developed from SOT recipients to stratify mortality risk, but an external validation is lacking.

METHODS

Multicenter retrospective cohort study of liver transplant (LT) recipients colonized with CRE infection who developed infection after transplant over 7-year period. Primary endpoint was all-cause 30-day mortality from infection onset. A comparison between INCREMENT-SOT-CPE and other selected scores was performed. A two-level mixed effects logistic regression model with random effects for the center was fitted. Performance characteristics at optimal cut-point were calculated. Multivariable Cox regression analysis of risk factors for all-cause 30-day mortality was carried out.

RESULTS

Overall, 250 CRE carriers developed infection after LT and were analyzed. The median age was 55 years (interquartile range [IQR]: 46-62) and 157 were males (62.8%). All-cause 30-day mortality was 35.6%. A sequential organ failure assessment (SOFA) score ≥ 11 showed a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 69.7%, 76.4%, 62.0%, 82.0%, and 74.0%, respectively. An INCREMENT-SOT-CPE ≥ 11 reported a sensitivity, specificity, PPV, NPV, and accuracy of 73.0%, 62.1%, 51.6%, 80.6% and 66.0%, respectively. At multivariable analysis acute renal failure, prolonged mechanical ventilation, INCREMENT-SOT-CPE score ≥ 11 and SOFA score ≥ 11 were independently associated with all-cause 30-day mortality, while a tigecycline-based targeted regimen was found to be protective.

CONCLUSIONS

Both INCREMENT-SOT-CPE ≥ 11 and SOFA ≥ 11 were identified as strong predictors of all-cause 30-day mortality in a large cohort of CRE carriers developing infection after LT.

Relationship between immune response to SARS-CoV2 vaccines and development of breakthrough infection in solid organ transplant recipients: the CONTRAST cohort

BACKGROUND

SARS-CoV-2 vaccination in solid organ transplant (SOT) is associated with poorer antibody response (AbR) compared to non-SOT recipients. However, its impact on the risk of breakthrough infection (BI) should yet be assessed.

METHODS

Single-center prospective longitudinal cohort study enrolling adult SOT recipients who received SARS-CoV2 vaccination during 1-year period from February 2021, and followed-up to April 30th 2022. Patients were tested for AbR at multiple timepoints. Primary endpoint was BI (laboratory confirmed SARS-CoV2 infection ≥14 days after 2nd dose). Immunization (positive AbR) was considered an intermediate state between vaccination and BI. Probabilities of being in vaccination, immunization and BI states were obtained for each type of graft and vaccination sequence with multistate survival analysis, then multivariable logistic regression was performed to analyse the risk of BI in AbR levels.

RESULTS

614 SOT (275 kidney, 163 liver, 137 heart, 39 lung) recipients were included. Most patients (84.7%) received three vaccine doses, the first two consisted of BNT162b2 and mRNA-1273 in 73.5% and 26.5% of cases, respectively; while at the third dose mRNA-1273 was administered in 59.8% of patients. Overall, 75.4% of patients reached immunization and 18.4% developed BI. Heart transplant recipients showed lowest probability of immunization (0.418) and highest of BI (0.323), all-mRNA-1273 vaccine-sequence showed higher probability of immunization (0.732) and lowest of BI (0.098). Risk of BI was higher for non-high-level AbR, younger age and shorter time from transplant.

CONCLUSIONS

SOT patients with non-high-level AbR, shorter time from transplantation, and heart recipients are at highest risk of BI.

Risk factors associated with bacteremia in COVID-19 patients admitted to intensive care unit: a retrospective multicenter cohort study

PURPOSE

This multicenter observational study was done to evaluate risk factors related to the development of BSI in patients admitted to ICU for COVID-19.

METHODS

All patients with COVID-19 admitted in two COVID-19 dedicated ICUs in two different hospital between 02-2020 and 02-2021 were recruited.

RESULT

537 patients were included of whom 265 (49.3%) experienced at least one BSI. Patients who developed bacteremia had a higher SOFA score [10 (8-12) vs 9 (7-10), p < 0.001], had been intubated more frequently [95.8% vs 75%, p < 0.001] and for a median longer time [16 days (9-25) vs 8 days (5-14), p < 0.001]. Patients with BSI had a median longer ICU stay [18 days (12-31.5) vs 9 days (5-15), p < 0.001] and higher mortality [54% vs 42.3%, p < 0.001] than those who did not develop it. Development of BSI resulted in a higher SOFA score [aHR 1.08 (95% CI 1.03-1.12)] and a higher Charlson score [csAHR 1.15 (95% CI 1.05-1.25)].

CONCLUSION

A high SOFA score and a high Charlson score resulted associated with BSI's development. Conversely, immunosuppressive therapy like steroids and tocilizumab, has no role in increasing the risk of bacteremia.

1089. Evaluation of breakthrough infections in solid organ transplant recipients: the prospective CONTRAST cohort

Background

Solid organ transplant (SOT) recipients are at higher risk than general population for complicated COVID-19 course. Moreover COVID-19 vaccination in this setting is associated with a suboptimal immune response. However, the impact of this finding on the risk of breakthrough infection (BI) in SOT recipients has to be yet determined.

Methods

Single-center prospective longitudinal cohort of adult SOT recipients who received three doses of mRNA COVID-19 vaccine between February and December 2021 and were followed up to March 30 2022. Patients were tested for antibody response at several timepoints (1 st dose, 2 nd dose, 3±1 month after 1 st dose, and 1 month after 3 rd dose). Main endpoints were: i) BI defined as laboratory confirmed SARS-CoV2 infection diagnosed ≥14 day after 2 nd dose; ii) positive antibody response (AbR) defined as anti-rapid binding domain titer ≥5 U/ml determined by Elecsys Anti-SARS-CoV-2 ECLIA assay (Roche Diagnostics, CH), the last available determination before BI was considered.

Results

Study cohort consists of 642 SOT (277 kidney, 191 liver, 144 heart, 37 lung) recipients: 63.9% males, median age 54 ± 14.5 years. Of them, 111 (17.8%) developed BI, BI rates were 19.9%, 18.1%, 15.2% and 10.8% among liver, heart, kidney and lung transplant recipients, respectively. Positive-AbR was observed in 60% of all patients, but rates varied from 8.7% to 91.3% among patients with BI and without BI, respectively. Predictors of BI infection at multivariable analysis were liver (vs. other grafts) transplant (OR 2.98, 95%CI 1.47-6.03), mycophenolate (1.63, 0.92-2.88) and steroids (1.8, 1.05- 3.33), while positive-AbR (0.61, 0.35-1.04) and age (0.97, 0.95-0.99) were protective. On the other hand, liver transplant (1.94, 1.02-3.69), time from transplant (1.09, 1.05-1.21), and Moderna vaccine (2.32, 1.46-3.70) were associated with positive-AbR, while age (0.97, 0.95-0.98), heart transplant (0.56, 0.33-0.96), mycophenolate (0.65, 0.39-1.06) and steroids (0.39, 0.23-0.65) with lower probability of positive-AbR.

Conclusion

Although associated with positive-AbR, liver transplant and younger age were also BI predictors, suggesting the importance of social factors and the controversial role of immune monitoring.

Disclosures

All Authors: No reported disclosures.

214. The impact of preservation fluid culture on graft site arteritis: a systematic review and metanalysis

Background

The role of culturing the graft preservation fluid (PF) is controversial and its impact on graft arteritis development remains unclear.

Methods

Systematic literature search retrieving all-languages observational studies comparing SOT recipients with culture positive PF versus culture negative PF. Graft site arteritis within 180 days from transplant was selected as primary outcome. Data were independently extracted using a pre-specified form, and quality of included studies was independently assessed according to ROBINS-I tool for observational studies. Meta-analysis was performed using Mantel-Haenszel random-effect models.

Results

2,492 articles were screened, and twenty-one observational studies (N=2,208 positive PF vs. 4,458 negative) were included in the meta-analyses. Among positive PF, 857 (38.8%) were classified as high-risk group pathogens (fungi, Gram negative, Enterococcus spp., beta-hemolytic streptococci and Staphylococcus aureus) and 1,351 (61.2%) as low-risk (mostly coagulase negative Staphylococci) pathogens. A significant higher risk of graft arteritis was found in SOT recipients with a PF yielding a high-risk pathogen (odds ratio [OR] 18.43, 95%CI 7.83-43.40), with low heterogeneity (I²=2.24%). Similar results were found considering separately high-risk bacteria (OR 12.02, 95%CI 4.88-29.60) and fungi (OR 71.00, 95%CI 28.07–179.56), with no heterogeneity (I²=0%), and in the subgroup analyses of liver (OR 16.78, 95%CI 2.95–95.47) and kidney (OR 19.90, 95%CI 4.78–82.79) recipients. However, data about diagnostic features of graft arteritis were very limited, indeed for only 11 of the 93 events histological or microbiological results were reported.

Conclusion

Our results may support the performance of PF culturing and a preemptive diagnostic or therapeutic management upon isolation of high-risk pathogen. Further studies based on reliable diagnosis of graft arteritis are needed to confirm our findings.

Disclosures

All Authors: No reported disclosures.

The impact of preservation fluid culture on graft site arteritis: A systematic review and meta-analysis

BACKGROUND

The role of culturing the graft preservation fluid (PF) is controversial and its impact on graft arteritis development remains unclear.

METHODS

Systematic literature search retrieving observational studies comparing solid organ transplant (SOT) recipients with culture-positive PF versus culture-negative PF. The quality of included studies was independently assessed according to the ROBINS-I tool for observational studies. Meta-analysis was performed using Mantel-Haenszel random-effect models. Graft site arteritis within 180 days from transplant was selected as the primary outcome.

RESULTS

Twenty-one observational studies (N = 2208 positive PF vs. 4458 negative) were included. Among positive PF, 857 (38.8%) were classified as high-risk group pathogens and 1351 (61.2%) as low-risk pathogens. Low-risk and negative PF showed similar odds ratios. A significant higher risk of graft arteritis was found in SOT recipients with a PF yielding a high-risk pathogen (odds ratio [OR] 18.43, 95% confidence interval [CI] 7.83-43.40) compared to low-risk and negative PF, with low heterogeneity (I² = 2.24%). Similar results were found considering separately high-risk bacteria (OR 12.02, 95%CI 4.88-29.60) and fungi (OR 71.00, 95%CI 28.07-179.56), with no heterogeneity (I² = 0%), and in the subgroup analyses of the liver (OR 16.78, 95%CI 2.95-95.47) and kidney (OR 19.90, 95%CI 4.78-82.79) recipients. However, data about diagnostic features of graft arteritis were very limited, indeed for only 11 of the 93 events histological or microbiological results were reported.

CONCLUSIONS

Our results may support the performance of PF culturing and a preemptive diagnostic or therapeutic management upon isolation of high-risk pathogens. Further studies based on a reliable diagnosis of graft arteritis are needed.

Mortality among Italians and immigrants with COVID-19 hospitalised in Milan, Italy: data from the Luigi Sacco Hospital registry

BACKGROUND

To compare differences in the probability of COVID-19-related death between native Italians and immigrants hospitalised with COVID-19.

METHODS

This retrospective study of prospectively collected data was conducted at the ASST Fatebenefratelli-Sacco Hospital in Milan, Italy, between 21 February and 31 November 2020. Uni- and multivariable Cox proportional hazard models were used to assess the impact of the patients' origin on the probability of COVID-19-related death.

RESULTS

The study population consisted of 1,179 COVID-19 patients: 921 Italians (78.1%) and 258 immigrants (21.9%) who came from Latin America (99, 38%), Asia (72, 28%), Africa (50, 19%) and central/eastern Europe (37, 14%). The Italians were significantly older than the immigrants (median age 70 years, interquartile range (IQR) 58-79 vs 51 years, IQR 41-60; p < 0.001), and more frequently had one or more co-morbidities (79.1% vs 53.9%; p < 0.001). Mortality was significantly greater among the Italians than the immigrants as a whole (26.6% vs 12.8%; p < 0.001), and significantly greater among the immigrants from Latin America than among those from Asia, Africa or central/eastern Europe (21% vs 8%, 6% and 8%; p = 0.016). Univariable analysis showed that the risk of COVID-19-related death was lower among the immigrants (hazard ratio [HR] 0.43, 95% confidence interval [CI] 0.30-0.63; p < 0.0001], but the risk of Latin American immigrants did not significantly differ from that of the Italians (HR 0.74, 95% CI 0.47-1.15; p = 0.183). However, after adjusting for potential confounders, multivariable analysis showed that there was no difference in the risk of death between the immigrants and the Italians (adjusted HR [aHR] 1.04, 95% CI 0.70-1.55; p = 0.831), but being of Latin American origin was independently associated with an increased risk of death (aHR 1.95, 95% CI 1.17-3.23; p = 0.010).

CONCLUSIONS

Mortality was lower among the immigrants hospitalised with COVID-19 than among their Italian counterparts, but this difference disappeared after adjusting for confounders. However, the increased risk of death among immigrants of Latin American origin suggests that COVID-19 information and prevention initiatives need to be strengthened in this sub-population.

The value of lamp to rule out imported malaria diagnosis: a retrospective observational study in Milan, Italy

BACKGROUND

The diagnosis of malaria in returning travellers could be a challenge in non-endemic settings. We aimed to assess the performance of LAMP in comparison with standard conventional diagnostic methods using real-time-polymerase chain reaction (PCR) in case of discordant results.

METHODS

All travellers returning from malaria-endemic areas who presented to our Emergency Department (ED) from January 2017 to December 2020 with signs and symptoms suggestive for malaria were included. Blood microscopy was the reference diagnostic method applied at our laboratory with LAMP implemented as an additional method to aid in malaria diagnosis. PCR was employed only in case of between test's discordant results. Sensitivity and specificity of microscopy compared to LAMP were calculated with the confidence interval of 95%.

RESULTS

Four-hundred and eight patients (55.6% male, median age 42 years) were screened for malaria. The diagnosis was confirmed in 49 cases (12%): 44 cases (90%) caused by Plasmodium falciparum. Peripheral blood smear missed to identify three malaria cases, which tested positive with LAMP and PCR. One case of malaria caused by P. malariae in a naive tourist, one case by P. falciparum in a semi-immune pregnant women and one case by P. falciparum in a previously treated semi-immune patient. All the discordant cases were characterized by a very low parasitaemia. Microscopy when compared to LAMP showed a sensitivity of 93.9% (95% confidence interval (CI) 83.1-98.7%) and a specificity of 100% (95% CI 98.9-100%).

CONCLUSIONS

In our non-endemic setting LAMP was able to identify malaria cases with low-level parasitaemia otherwise missed by blood microscopy.

Brief Report: Impact of the COVID-19 Pandemic on Virological Suppression in People Living With HIV Attending a Large Italian HIV Clinic

BACKGROUND

We assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on HIV suppression rates in people living with HIV (PLWH) attending a large Italian HIV clinic.

SETTING

The HIV outpatient clinic of the Infectious Diseases Department of Luigi Sacco Hospital, Milan, Italy, which serves more than 5000 PLWH per year.

METHODS

A before and after quasi-experimental study design was used to make a retrospective assessment of the monthly trend of HIV-RNA determinations of ≥50 among the PLWH attending our clinic, with "before" being the period from January 1, 2016 to February 20, 2020, and "after" being the period from February 21, 2020 to December 31, 2020 (the COVID-19 period). Interrupted time series analysis was used to evaluate any changes in the trend.

RESULTS

During the study period, 70,349 HIV-RNA viral load determinations were made, and the percentage of HIV-RNA viral load determinations of <50 copies/mL increased from 88.4% in 2016 to 93.2% in 2020 (P < 0.0001). There was a significant monthly trend toward a decrease in the number of HIV-RNA determinations of ≥50 copies/mL before the pandemic (β -0.084; standard error 0.015; P < 0.001), and this did not significantly change after it started (β -0.039, standard error 0.161; P = 0.811).

CONCLUSIONS

A high prevalence of viral suppression was maintained among the PLWH referring to our clinic, despite the structural barriers raised by the COVID-19 pandemic. The use of simplified methods of delivering care (such as teleconsultations and multiple antiretroviral treatment prescriptions) may have contributed to preserving this continuum.

Non-human primate and human malaria: past, present and future

BACKGROUND

Studies of the malaria parasites infecting various non-human primates (NHPs) have increased our understanding of the origin, biology and pathogenesis of human Plasmodium parasites.This review considers the major discoveries concerning NHP malaria parasites, highlights their relationships with human malaria and considers the impact that this may have on attempts to eradicate the disease.

RESULTS

The first description of NHP malaria parasites dates back to the early 20th century. Subsequently, experimental and fortuitous findings indicating that some NHP malaria parasites can be transmitted to humans have raised concerns about the possible impact of a zoonotic malaria reservoir on efforts to control human malaria.Advances in molecular techniques over the last 15 years have contributed greatly to our knowledge of the existence and geographical distribution of numerous Plasmodium species infecting NHPs, and extended our understanding of their close phylogenetic relationships with human malaria parasites. The clinical application of such techniques has also made it possible to document ongoing spillovers of NHP malaria parasites (Plasmodium knowlesi, P. cynomolgi, P. simium, P. brasilianum) in humans living in or near the forests of Asia and South America, thus confirming that zoonotic malaria can undermine efforts to eradicate human malaria.

CONCLUSIONS

Increasing molecular research supports the prophetic intuition of the pioneers of modern malariology who saw zoonotic malaria as a potential obstacle to the full success of malaria eradication programmes. It is, therefore, important to continue surveillance and research based on one-health approaches in order to improve our understanding of the complex interactions between NHPs, mosquito vectors and humans during a period of ongoing changes in the climate and the use of land, monitor the evolution of zoonotic malaria, identify the populations most at risk and implement appropriate preventive strategies.

Impact of switching to TAF/FTC/RPV, TAF/FTC/EVG/cobi and ABC/3TC/DTG on cardiovascular risk and lipid profile in people living with HIV: a retrospective cohort study

BACKGROUND

We aimed to assess the overall cardiovascular and metabolic effect of the switch to three different single tablet regimens (STRs) [tenofovir alafenamide/emtricitabine/rilpivirine (TAF/FTC/RPV), TAF/FTC/elvitegravir/cobi (TAF/FTC/EVG/cobi) and ABC/lamivudine/dolutegravir (ABC/3TC/DTG)] in a cohort of people living with HIV/AIDS (PLWH) under effective ART.

METHODS

All PLWH aged above 18 years on antiretroviral treatment with an HIV-RNA < 50 cp/mL at the time of the switch to TAF/FTC/RPV, TAF/FTC/EVG/cobi and ABC/3TC/DTG were retrospectively included in the analysis. Framingham risk score modification after 12 months from the switch such as lipid profile and body weight modification were assessed. The change from baseline to 12 months in mean cardiovascular risk and body weight in each of the STR's group were assessed by means of Wilcoxon signed-rank test whereas a mixed regression model was used to assess variation in lipid levels.

RESULTS

Five-hundred and sixty PLWH were switched to an STR regimen of whom 170 (30.4%) to TAF/FTC/EVG/cobi, 191 (34.1%) to TAF/FTC/RPV and 199 (35.5%) to ABC/3TC/DTG. No difference in the Framingham cardiovascular risk score was observed after 12 months from the switch in each of the STR's groups. No significant overtime variation in mean total cholesterol levels from baseline to 12 months was observed for PLWH switched to ABC/3TC/DTG [200 (SD 38) mg/dl vs 201 (SD 35) mg/dl; p = 0.610] whereas a significant increment was observed in PLWH switched to TAF/FTC/EVG/cobi [192 (SD 34) mg/dl vs 208 (SD 40) mg/dl; p < 0.0001] and TAF/FTC/RPV [187 (SD 34) mg/dl vs 195 (SD 35) mg/dl; p = 0.027]. In addition, a significant variation in the mean body weight from baseline to 12 months was observed in PLWH switched to TAF/FTC/EVG/cobi [72.2 (SD 13.5) kilograms vs 74.6 (SD 14.3) kilograms; p < 0.0001] and TAF/FTC/RPV [73.4 (SD 11.6) kilograms vs 75.6 (SD 11.8) kilograms; p < 0.0001] whereas no difference was observed in those switched to ABC/3TC/DTG [71.5 (SD 12.8) kilograms vs 72.1 (SD 12.6) kilograms; p = 0.478].

CONCLUSION

No difference in the cardiovascular risk after 1 year from the switch to these STRs were observed. PLWH switched to TAF/FTC/EVG/cobi and TAF/FTC/RPV showed an increase in total cholesterol levels and body weight 12 months after the switch.

Impact of gender on patients hospitalized for SARS-COV-2 infection: A prospective observational study

Biological sex could affect the natural history of severe acute respiratory syndrome coronavirus 2 infection. We enrolled all COVID‐19 patients admitted to two COVID‐19 hospitals in Milan in a prospective observational study. The primary outcome was death during the study period and the secondary outcome was critical disease at hospital admission. The association(s) between clinically relevant, noncollinear variables, and the primary outcome was assessed with uni‐ and multivariable Logistic regression models. A total of 520 patients were hospitalized of whom 349 (67%) were males with a median age 61 (interquartile range: 50–72). A higher proportion of males presented critically ill when compared to females (30.1% vs. 18.7%, p < .046). Death occurred in 86 (24.6%) males and 27 (15.8%) females (p = .024). In multivariable analysis age (per 10 years more) (adjusted odds ratio [AOR]: 1.83 [95% confidence interval {CI}: 1.42–2.35], p < .0001), obesity (AOR: 2.17 [95% CI: 1.10–4.31], p = .026), critical disease at hospital admission (AOR 6.34 [95% CI: 3.50–11.48], p < .0001) were independently associated to higher odds of death whereas gender was not. In conclusion, a higher proportion of males presented critically ill at hospital admission. Age, critical disease at hospital admission, obesity, anemia, D‐dimer, estimated glomerular filtration rate, lactate dehydrogenase, and creatine kinase predicted death in hospitalized COVID‐19 patients.

Trypanosoma cruzi infection in Latin American pregnant women living outside endemic countries and frequency of congenital transmission: a systematic review and meta-analysis

BACKGROUND

Chagas disease, as a consequence of globalization and immigration, is no more restricted to Central and Latin America. Therefore, congenital transmission represents a growing public health concern in non-endemic countries.

METHODS

The aim of this study was to assess the prevalence of Trypanosoma cruzi infection in pregnant Latin American (LA) women living outside endemic countries and the rate of congenital transmission. Data were extracted from studies indexed in PubMed, Scopus, Embase, Lilacs and SciELO databases without language restriction. Two investigators independently collected data on study characteristics, diagnosis, prevalence of infection in pregnant women and congenital infection rate. The data were pooled using a random effects model.

RESULTS

The search identified 1078 articles of which 29 were eligible regarding prevalence of T. cruzi infection among pregnant women and 1795 articles of which 32 were eligible regarding the congenital transmission rate. The estimated pooled prevalence of T. cruzi infection in LA pregnant women was 4.2% [95% confidence interval (CI): 3.0-5.5]. The prevalence of T. cruzi infection in pregnant women from Bolivia was 15.5% (95% CI: 11.7-19.7) and 0.5% (95% CI: 0.2-0.89) for those coming from all other LA countries. The estimated global rate of congenital transmission was 3.5% (95% CI: 2.5-4.5); excluding poor-quality studies, the rate of congenital transmission was 3.8% (95% CI: 2.4-5.1).

CONCLUSIONS

Prevalence of Chagas disease among LA pregnant women living outside endemic countries is high, particularly in Bolivian women. The rate of vertical transmission of T. cruzi infection is similar to the rate reported in South and Central American countries.

Unexpectedly High Frequency of Enterococcal Bloodstream Infections in Coronavirus Disease 2019 Patients Admitted to an Italian ICU: An Observational Study

OBJECTIVES

We aimed to assess the frequency of ICU-acquired bloodstream infections in coronavirus disease 2019 patients.

DESIGN

Retrospective observational study.

SETTING

The emergency expansion of an ICU from eight general beds to 30 coronavirus disease 2019 beds.

PARTICIPANTS

Patients with coronavirus disease 2019 admitted to the ICU of Luigi Sacco Hospital (Milan, Italy) for greater than or equal to 48 hours between February 21, 2020, and April 30, 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The frequency of bloodstream infections per 1,000 days of ICU stay was calculated in 89 coronavirus disease 2019 patients, and the cumulative probability of bloodstream infection was estimated using death and ICU discharge as competing events. Sixty patients (67.4%) experienced at least one of the 93 recorded episodes of bloodstream infection, a frequency of 87 per 1,000 days of ICU stay (95% CI, 67-112).The patients who experienced a bloodstream infection had a higher Sequential Organ Failure Assessment score upon ICU admission (9.5; interquartile range, 8-12 vs 8, interquartile range, 5-10; p = 0.042), a longer median ICU stay (15 d; interquartile range, 11-23 vs 8, interquartile range, 5-12; p < 0.001), and more frequently required invasive mechanical ventilation (98.3% vs 82.8%; p = 0.013) than those who did not. The median time from ICU admission to the first bloodstream infection episode was 10 days. Gram-positive bacteria accounted for 74 episodes (79.6%), with Enterococcus species being the most prevalent (53 episodes, 55.8%). Thirty-two isolates (27.3%) showed multidrug resistance.

CONCLUSIONS

Coronavirus disease 2019 seemed to increase the frequency of bloodstream infections (particularly Enterococcus-related bloodstream infection) after ICU admission. This may have been due to enteric involvement in patients with severe coronavirus disease 2019 and/or limitations in controlling the patient-to-patient transmission of infectious agents in extremely challenging circumstances.

A case of crusted scabies with a delayed diagnosis and inadequate therapy

Crusted scabies is an infrequent disease caused by Sarcoptes scabiei that usually affects patients with underlying medical conditions leading to immunosuppression. Here, we present the case of an 81 years old man, diagnosed with crusted scabies who came to our attention after multiple misdiagnosis and incorrect and potentially detrimental treatment with steroids. He was admitted to our inpatients ward and treated with oral ivermectin plus local permethrin. The hospitalization was complicated by a secondary bacterial skin infection caused by methicillin-sensitive Staphylococcus aureus. Crusted scabies is commonly misdiagnosed in elderly and immunosuppressed people due to its unusual occurrence and atypical clinical presentation. It should be considered in the differential diagnosis of skin lesions associated with pruritus in patients with underling medical conditions leading to immunosuppression. A prompt diagnosis and treatment are warranted due to the potential secondary infections and subsequent related morbidity and mortality.

Compassionate remdesivir treatment of severe Covid-19 pneumonia in intensive care unit (ICU) and Non-ICU patients: Clinical outcome and differences in post-treatment hospitalisation status

SARS-CoV-2 is causing an increasing number of deaths worldwide because no effective treatment is currently available. Remdesivir has shown in vitro activity against coronaviruses and is a possible antiviral treatment for SARS-CoV-2 infection. This prospective (compassionate), open-label study of remdesivir, which was conducted at Luigi Sacco Hospital, Milan, Italy, between February 23 and March 20, 2020, involved patients with SARS-CoV-2 pneumonia aged ≥18 years undergoing mechanical ventilation or with an oxygen saturation level of ≤94 % in air or a National Early Warning Score 2 of ≥4. The primary outcome was the change in clinical status based on a 7-category ordinal scale (1 = not hospitalised, resuming normal daily activities; 7 = deceased). The 35 patients enrolled from February 23 to March 20, 2020, included 18 in intensive care unit (ICU), and 17 in our infectious diseases ward (IDW). The 10-day course of remdesivir was completed by 22 patients (63 %) and discontinued by 13, of whom eight (22.8 %) discontinued because of adverse events. The median follow-up was 39 days (IQR 25-44). At day 28, 14 (82.3 %) patients from IDW were discharged, two were still hospitalized and one died (5.9 %), whereas in ICU 6 (33.3 %) were discharged, 8 (44.4 %) patients died, three (16.7 %) were still mechanically ventilated and one (5.6 %) was improved but still hospitalized. Hypertransaminasemia and acute kidney injury were the most frequent severe adverse events observed (42.8 % and 22.8 % of the cases, respectively). Our data suggest that remdesivir can benefit patients with SARS-CoV-2 pneumonia hospitalised outside ICU where clinical outcome was better and adverse events are less frequently observed. Ongoing randomised controlled trials will clarify its real efficacy and safety, who to treat, and when.

30-day mortality in patients hospitalized with COVID-19 during the first wave of the Italian epidemic: A prospective cohort study

Italy was the first European country hit by the COVID-19 pandemic and has the highest number of recorded COVID-19 deaths in Europe. This prospective cohort study of the correlates of the risk of death in COVID-19 patients was conducted at the Infectious Diseases and Intensive Care units of Luigi Sacco Hospital, Milan, Italy. The clinical characteristics of all the COVID-19 patients hospitalised in the early days of the epidemic (21 February -19 March 2020) were recorded upon admission, and the time-dependent probability of death was evaluated using the Kaplan-Meier method (censored as of 20 April 2020). Cox proportional hazard models were used to assess the factors independently associated with the risk of death. Forty-eight (20.6 %) of the 233 patients followed up for a median of 40 days (interquartile range 33-47) died during the follow-up. Most were males (69.1 %) and their median age was 61 years (IQR 50-72). The time-dependent probability of death was 19.7 % (95 % CI 14.6-24.9 %) 30 days after hospital admission. Age (adjusted hazard ratio [aHR] 2.08, 95 % CI 1.48-2.92 per ten years more) and obesity (aHR 3.04, 95 % CI 1.42-6.49) were independently associated with an increased risk of death, which was also associated with critical disease (aHR 8.26, 95 % CI 1.41-48.29), C-reactive protein levels (aHR 1.17, 95 % CI 1.02-1.35 per 50 mg/L more) and creatinine kinase levels above 185 U/L (aHR 2.58, 95 % CI 1.37-4.87) upon admission. Case-fatality rate of patients hospitalized with COVID-19 in the early days of the Italian epidemic was about 20 %. Our study adds evidence to the notion that older age, obesity and more advanced illness are factors associated to an increased risk of death among patients hospitalized with COVID-19.

Impact of HCV eradication with direct-acting antiviral agents on serum gamma globulin levels in HCV and HCV/HIV coinfected patients

BACKGROUND

chronic viral infections by both HCV and HIV may lead to polyclonal activation of B cells resulting in hypergammaglobulinemia. This study retrospectively analyzed the effect of HCV eradication with interferon-free direct-acting antiviral agents (DAAs) on the gamma globulin levels in HCV-infected patients with or without HIV coinfection to identify factors potentially associated with gamma globulins decrease.

METHODS

The charts of patients treated with DAAs for HCV chronic infection between January 2015-June 2019 were retrospectively reviewed. Gamma globulin levels before treatment and 12 weeks after the end of anti-HCV therapy were evaluated along with liver tests, liver fibrosis stage by elastography, SVR achievement, HIV-coinfection. Multivariate analyses were carried out to assess the factors and the potential confounders related to the changes in gamma globulin levels.

RESULTS

A significant decrease of gamma globulin concentration was found in both cirrhotic and non-cirrhotic HCV-infected patients after treatment (from mean ± SD of 1.5 ± 0.44 g/dL to 1.31 ± 0.37 g/dL; p = 0.0001). Adjusted linear regression analyses of serum gamma globulin changes from baseline to SVR12 showed a positive significant association with pre-treatment gamma-globulin levels (β-coefficient -0.23; p = 0.0001), Metavir fibrosis score (β-coefficient -0.74; p = 0.008), ALT values and baseline HCV-RNA levels > 800,000. No difference was found between HIV-infected and HIV-uninfected patients.

CONCLUSIONS

Our study confirms previous preliminary observation of the decrease of serum gamma globulins after HCV eradication either achieved with interferon-based therapy or with DAAs, suggesting a leading role of the virus on the activation of B cell compartment and gamma globulins production.

Chagas disease in Italy: the study's contribution of Italian researchers

Chagas disease (CD) is an emerging infection in Italy as the consequence of the huge immigration from Latin American countries observed during the last ten-fifteen years. However, the interest of Italian researchers on CD dates back to the '80-90s of the last century with studies conducted in collaboration with Brazilian and Argentinian colleagues by Italian cardiologists and pathologists. Moreover, the first demonstration of the existence in the pre-Columbian America of Chagas disease in a Peruvian mummy was made by a group of Italian paleopathologists. Seroprevalence studies performed between 2010-2014 in Negrar (Verona), Bergamo, Milan, Florence and Rome shows Trypanosoma cruzi infection ranging from 3.9% to 17.1% with people coming from Bolivia as the most affected. As observed in Latin America about 30% of screened subjects in Italy are affected by cardiac or digestive forms of CD. More than 20% of subjects treated with benznidazole discontinued it permanently due to adverse events.