Duration of antibiotic therapy for multidrug resistant Pseudomonas aeruginosa pneumonia: is shorter truly better?

BACKGROUND: The 2016 IDSA guideline recommends a treatment duration of at least 7 days for hospital-acquired (HAP)/ventilator-associated pneumonia (VAP). The limited literature has demonstrated higher rates of recurrence for non-glucose fermenting gram-negative bacilli with short course therapy, raising the concern of optimal treatment duration for these pathogens. Therefore, we aimed to compare the outcomes for patients receiving shorter therapy treatment (≤ 8 days) versus longer regimen (> 8 days) for the treatment of multidrug resistant (MDR) Pseudomonas pneumonia. METHODS: A single-center, retrospective cohort study was conducted to evaluate adult patients receiving an antimicrobial regimen with activity against MDR Pseudomonas aeruginosa in respiratory culture between 2017 and 2020 for a minimum of 6 consecutive days. Exclusion criteria were inmates, those with polymicrobial pneumonia, community-acquired pneumonia, and infections requiring prolonged antibiotic therapy. RESULTS: Of 427 patients with MDR P. aeruginosa respiratory isolates, 85 patients were included. Baseline characteristics were similar among groups with a median age of 65.5 years and median APACHE 2 score of 20. Roughly 75% had ventilator-associated pneumonia. Compared to those who received ≤ 8 days of therapy, no difference was seen for clinical success in patients treated for more than 8 days (80% vs. 65.5%, p = 0.16). The number of 30-day and 90-day in-hospital mortality, 30-days relapse, and other secondary outcomes did not significantly differ among the treatment groups. CONCLUSIONS: Prolonging treatment duration beyond 8 days did not improve patient outcomes for MDR P. aeruginosa HAP/VAP.

Prevalence of methicillin-resistant Staphylococcus aureus (MRSA) harboring mupirocin and biocide resistance genes in a large health care system.

BACKGROUND: We aimed to determine the prevalence of genes associated with high-level mupirocin and biocide resistance in methicillin-resistant Staphylococcus aureus (MRSA) isolates among hospitalized patients and to characterize their genomic and epidemiologic features. METHODS: Study conducted on an integrated health system. Clinical cultures with MRSA from hospitalized patients collected between March 1, 2023, and January 20, 2024 underwent prospective whole-genome sequencing, including assessment for the presence of markers of resistance against mupirocin (mupA) and biocides (qac). Demographic and clinical characteristics were reviewed. RESULTS: We analyzed 463 MRSA isolates. The overall prevalence of mupA(+), qacA(+), and qacC(+) genes was 22.0%, 2.4%, and 19.0%, respectively. Most mupA(+) isolates belonged to ST8, but ST8732 (a novel variant of ST8) had the highest prevalence of mupA(+) isolates at 95%. Patients mupA(+) were older, and none of the isolates from pediatric patients harbored this gene. DISCUSSION: Through prospective whole-genome sequencing of MRSA isolates, we detected a prevalence of genes conferring mupirocin resistance considerably higher than previously reported, particularly among MRSA ST8 variants. CONCLUSIONS: Our findings highlight the need for monitoring resistance to agents used for the prevention of S aureus infections, as these trends have implications for infection prevention programs and public health at large.

Factors Associated with Poor Clinical and Microbiologic Outcomes in C. auris Bloodstream Infection: A Multicenter Retrospective Cohort Study.

BACKGROUND: C. auris has become a growing concern worldwide due to increases in incidence of colonization and reports of invasive infections. There are limited data on clinical factors associated with poor outcomes in patients with C. auris bloodstream infection (BSI). METHODS: We assembled a multicenter retrospective cohort of patients with C. auris BSI from two geographics areas in US healthcare settings. We collected data on demographic, clinical, and microbiologic characteristics to describe the cohort and constructed multivariate logistic regression models to understand risk factors for two clinical outcomes, all-cause mortality during facility admission, and blood culture clearance. RESULTS: Our cohort consisted of 187 patients with C. auris BSI (56.1% male, 55.6% age >65 years); 54.6% died by facility discharge and 66.9% (of 142 with available data) experienced blood culture clearance. Pitt bacteremia score at infection onset was associated with mortality (odds-ratio [95% confidence interval]: 1.19 [1.01,1.40] per 1-point increase). Hemodialysis was associated with a reduced odds of microbiologic clearance (0.15 [0.05,0.43]) and with mortality (3.08 [1.27,7.50]). CONCLUSIONS: The Pitt bacteremia score at the onset of C. auris BSI may be a useful tool in identifying patients at risk for mortality. Targeted infection prevention practices in patients receiving hemodialysis may be useful to limit poor outcomes.

Difficult-to-treat (DTR) Pseudomonas aeruginosa harboring Verona-Integron metallo-ß-lactamase (blaVIM): infection management and molecular analysis.

Pseudomonas aeruginosa harboring Verona Integron-encoded metallo-ß-lactamase enzymes (VIM-CRPA) have been associated with infection outbreaks in several parts of the world. In the US, however, VIM-CRPA remain rare. Starting in December 2018, we identified a cluster of cases in our institution. Herein, we present our epidemiological investigation and strategies to control/manage these challenging infections. This study was conducted in a large academic healthcare system in Miami, FL, between December 2018 and January 2022. Patients were prospectively identified via rapid molecular diagnostics when cultures revealed carbapenem-resistant P. aeruginosa. Alerts were received in real time by the antimicrobial stewardship program and infection prevention teams. Upon alert recognition, a series of interventions were performed as a coordinated effort. A retrospective chart review was conducted to collect patient demographics, antimicrobial therapy, and clinical outcomes. Thirty-nine VIM-CRPA isolates led to infection in 21 patients. The majority were male (76.2%); the median age was 52 years. The majority were mechanically ventilated (n = 15/21; 71.4%); 47.6% (n = 10/21) received renal replacement therapy at the time of index culture. Respiratory (n = 20/39; 51.3%) or bloodstream (n = 13/39; 33.3%) were the most common sources. Most infections (n = 23/37; 62.2%) were treated with an aztreonam-avibactam regimen. Six patients (28.6%) expired within 30 days of index VIM-CRPA infection. Fourteen isolates were selected for whole genome sequencing. Most of them belonged to ST111 (12/14), and they all carried blaVIM-2 chromosomally. This report describes the clinical experience treating serious VIM-CRPA infections with either aztreonam-ceftazidime/avibactam or cefiderocol in combination with other agents. The importance of implementing infection prevention strategies to curb VIM-CRPA outbreaks is also demonstrated.

Navigating the Challenges of Candida auris Colonization in Rehabilitation Settings.

ABSTRACT: Candida auris is a highly transmissible yeast that is capable of causing invasive and fatal infections, particularly among persons with underlying medical conditions. Its incidence is rising, especially among patients cared for in post-acute care facilities. Individuals colonized with the yeast may be cared for in inpatient rehabilitation settings, without heightened risk for invasive infection and/or transmission to others, as long as appropriate infection control measures are followed. This article reviews key information for rehabilitation nurses caring for persons with C. auris , including risk factors for infection, the need for contact precautions, appropriate disinfection practices for therapy and diagnostic equipment, and critical components of safe transitions in the care of these patients.

An international prospective study of INICC analyzing the incidence and risk factors for catheter-associated urinary tract infections in 235 ICUs across 8 Asian Countries.

BACKGROUND: Identify urinary catheter (UC)-associated urinary tract infections (CAUTI) incidence and risk factors (RF) in 235 ICUs in 8 Asian countries: India, Malaysia, Mongolia, Nepal, Pakistan, the Philippines, Thailand, and Vietnam. METHODS: From January 1, 2014, to February 12, 2022, we conducted a prospective cohort study. To estimate CAUTI incidence, the number of UC days was the denominator, and CAUTI was the numerator. To estimate CAUTI RFs, we analyzed 11 variables using multiple logistic regression. RESULTS: 84,920 patients hospitalized for 499,272 patient days acquired 869 CAUTIs. The pooled CAUTI rate per 1,000 UC-days was 3.08; for those using suprapubic-catheters (4.11); indwelling-catheters (2.65); trauma-ICU (10.55), neurologic-ICU (7.17), neurosurgical-ICU (5.28); in lower-middle-income countries (3.05); in upper-middle-income countries (1.71); at public-hospitals (5.98), at private-hospitals (3.09), at teaching-hospitals (2.04). The following variables were identified as CAUTI RFs: Age (adjusted odds ratio [aOR] = 1.01; 95% CI = 1.01-1.02; P < .0001); female sex (aOR = 1.39; 95% CI = 1.21-1.59; P < .0001); using suprapubic-catheter (aOR = 4.72; 95% CI = 1.69-13.21; P < .0001); length of stay before CAUTI acquisition (aOR = 1.04; 95% CI = 1.04-1.05; P < .0001); UC and device utilization-ratio (aOR = 1.07; 95% CI = 1.01-1.13; P = .02); hospitalized at trauma-ICU (aOR = 14.12; 95% CI = 4.68-42.67; P < .0001), neurologic-ICU (aOR = 14.13; 95% CI = 6.63-30.11; P < .0001), neurosurgical-ICU (aOR = 13.79; 95% CI = 6.88-27.64; P < .0001); public-facilities (aOR = 3.23; 95% CI = 2.34-4.46; P < .0001). DISCUSSION: CAUTI rate and risk are higher for older patients, women, hospitalized at trauma-ICU, neurologic-ICU, neurosurgical-ICU, and public facilities. All of them are unlikely to change. CONCLUSIONS: It is suggested to focus on reducing the length of stay and the Urinary catheter device utilization ratio, avoiding suprapubic catheters, and implementing evidence-based CAUTI prevention recommendations.

Effectiveness of a sodium hypochlorite isotonic solution in decolonization of patients with Candida auris: Learnings from a county health care system.

BACKGROUND: Candida auris (CA) is an organism that has spread globally over the last decade. We conducted a quality improvement project with the aim of decreasing or eliminating skin colonization of patients with CA through a modified bathing protocol. METHODS: An isotonic hypochlorite solution was added to routine bathing protocols for hospitalized patients colonized with CA. Weekly skin swabs from axillary and inguinal areas were tested for the presence of CA using polymerase chain reaction and culture. Multidisciplinary efforts, such as environmental terminal cleaning, dedicated equipment, education, and signage were reinforced among staff to improve patient outcomes. RESULTS: A total of 24 patients were included. After 4 weeks of a modified bathing protocol, 81.2% of the patients remained colonized with CA. Three patients were discharged safely to their homes and 3 were transferred to long-term care acute hospitals. Nine patients remained hospitalized after 60 days. Localized rash was reported in 3 patients, which resolved after discontinuation of the product. CONCLUSIONS: Modification of our bathing protocols by including an isotonic hypochlorite solution did not lead to skin decolonization of CA. Further studies are needed to identify effective measures to eradicate, eliminate or reduce colonization.

Impact of In-house Candida auris Polymerase Chain Reaction Screening on Admission on the Incidence Rates of Surveillance and Blood Cultures With C. auris and Associated Cost Savings.

Background: The impact of strategies for rapid diagnostic screening of Candida auris on hospital operations has not been previously characterized. We describe the implementation of in-house polymerase chain reaction (PCR) testing on admission for screening of colonization with C. auris, associated process improvements, and financial impact. Methods: This study was conducted across an integrated health system. Patients were tested based on risk factors for C. auris carriage. Pre-intervention, the PCR was sent out to a reference laboratory, and postintervention was performed in-house. Changes in the incidence rates (IRs) of C. auris present on admission (CA-POA) and C. auris hospital-onset fungemia (CA-HOF) were assessed using interrupted time series analysis. The economic impact on isolation and testing costs was calculated. Results: Postintervention, the IR of CA-POA doubled (IRR, 2.57; 95% CI, 1.16-5.69; P = .02) compared with the pre-intervention period. The baseline rate of CA-HOF was increasing monthly by 14% (95% CI, 1.05-1.24; P = .002) pre-intervention, while during the postintervention period there was a change in slope with a monthly decrease in IR of 13% (95% CI, 0.80-0.99; P = .02). The median turnaround time (TAT) of the results (interquartile range) was reduced from 11 (8-14) days to 2 (1-3) days. Savings were estimated to be between $772 513.10 and $3 730 480.26. Conclusions: By performing in-house PCR for screening of C. auris colonization on admission, we found a doubling of CA-POA rates, a subsequent decrease in CA-HOF rates, reduced TAT for PCR results, and more efficient use of infection control measures. In-house testing was cost-effective in a setting of relatively high prevalence among individuals with known risk factors.

Disrupting the infectious disease ecosystem in the digital precision health era innovations and converging emerging technologies.

This commentary explores the convergence of precision health and evolving technologies, including the critical role of artificial intelligence (AI) and emerging technologies in infectious diseases (ID) and microbiology. We discuss their disruptive impact on the ID ecosystem and examine the transformative potential of frontier technologies in precision health, public health, and global health when deployed with robust ethical and data governance guardrails in place.

A Multicenter Retrospective Cohort Study to Characterize Patients Hospitalized With Multisystem Inflammatory Syndrome in Adults and Coronavirus Disease 2019 in the United States, 2020-2021.

BACKGROUND: The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated multisystem inflammatory syndrome in adults (MIS-A) requires distinguishing it from acute coronavirus disease 2019 (COVID-19) and may affect clinical management. METHODS: In this retrospective cohort study, we applied the US Centers for Disease Control and Prevention case definition to identify adults hospitalized with MIS-A at 6 academic medical centers from 1 March 2020 to 31 December 2021. Patients MIS-A were matched by age group, sex, site, and admission date at a 1:2 ratio to patients hospitalized with acute symptomatic COVID-19. Conditional logistic regression was used to compare demographic characteristics, presenting symptoms, laboratory and imaging results, treatments administered, and outcomes between cohorts. RESULTS: Through medical record review of 10 223 patients hospitalized with SARS-CoV-2-associated illness, we identified 53 MIS-A cases. Compared with 106 matched patients with COVID-19, those with MIS-A were more likely to be non-Hispanic black and less likely to be non-Hispanic white. They more likely had laboratory-confirmed COVID-19 ≥14 days before hospitalization, more likely had positive in-hospital SARS-CoV-2 serologic testing, and more often presented with gastrointestinal symptoms and chest pain. They were less likely to have underlying medical conditions and to present with cough and dyspnea. On admission, patients with MIS-A had higher neutrophil-to-lymphocyte ratio and higher levels of C-reactive protein, ferritin, procalcitonin, and D-dimer than patients with COVID-19. They also had longer hospitalization and more likely required intensive care admission, invasive mechanical ventilation, and vasopressors. The mortality rate was 6% in both cohorts. CONCLUSIONS: Compared with patients with acute symptomatic COVID-19, adults with MIS-A more often manifest certain symptoms and laboratory findings early during hospitalization. These features may facilitate diagnosis and management.

A retrospective study on 198 mpox cases in South Florida: Clinical characteristics and outcomes with focus on human immunodeficiency virus status.

BACKGROUND: Men who have sex with men (MSM) and persons living with human immunodeficiency virus (PLWH) were disproportionately affected by global mpox outbreak in 2022. In this retrospective review, we describe epidemiology and clinical characteristics of mpox infection in South Florida with a focus on human immunodeficiency virus (HIV) status. METHODS: This was a retrospective observational study of 198 adult patients with confirmed diagnosis of mpox between 01 January 2020, and 10 September 2022, in two large health systems in South Florida. A descriptive analysis was performed to summarize demographic, clinical and laboratory characteristics, and outcomes of the patients. RESULTS: Young male patients and PLWH were disproportionately represented among patients with mpox. HIV positive patients were less likely to have adenopathy and myalgia and were more likely to have oral or facial lesions. 22.7% of studied patients were diagnosed with one or more concurrent STI at the time of mpox diagnosis. CONCLUSIONS: We suggest screening for sexually transmitted infections and HIV for patients diagnosed with mpox. We suggest prompt consultation or referral to infectious disease specialist if needed for the patients who are diagnosed with mpox especially in the severely immunocompromised host.

Preventing Surgical Site Infections: Implementing Strategies Throughout the Perioperative Continuum.

Surgical site infections (SSIs) are a considerable cause of patient morbidity and mortality and are associated with increased hospital lengths of stay as well as increased health care costs to both patients and health care facilities. Substantial advances have been made in infection control practices throughout the perioperative setting to prevent SSIs and improve patient quality of care. Preventing and reducing SSIs requires a multifaceted approach encompassing the continuum of medical and surgical care. This article reviews four major infection prevention guidelines and provides an updated summary of effective strategies that perioperative team members can implement for the prevention of SSIs preoperatively, intraoperatively, and postoperatively.

Impact of a real-time diagnostic and antimicrobial stewardship workflow on time to appropriate therapy for infections caused by multidrug-resistant Gram-negative organisms.

INTRODUCTION: Multidrug-resistant (MDR) Gram-negative organisms cause life-threatening infections, and the incidence is rising globally. Timely therapy for these infections has a direct impact on patient survival. This study aimed to determine the impact of a multidisciplinary diagnostic and antimicrobial stewardship (AMS) workflow on time to appropriate therapy (TAP) for these infections using novel beta-lactam/beta-lactamase inhibitors. METHODS: This was a retrospective quasi-experimental study of adult patients with carbapenem-resistant Enterobacterales (CRE) and multidrug-resistant Pseudomonas (MDR PsA) infections at a 1500 bed university hospital. Included patients who received ≥ 72 hours of ceftazidime-avibactam (CZA) or ceftolozane-tazobactam (C/T) from December 2017 to December 2019. During the pre-intervention period (December 2017 to December 2018), additional susceptibilities (including CZA and C/T) were performed only upon providers' request. In 2019, reflex algorithms were implemented for faster identification and testing of all CRE/MDR PsA isolates. Results were communicated in real-time to the AMS team to tailor therapy. RESULTS: A total of 99 patients were included, with no between-group differences at baseline. The median age was 60 years and 56 (56.7%) were in intensive care at the time of culture collection. Identified organisms included 71 (71.7%) MDR PsA and 26 CRE, of which 18 were carbapenemase producers (Klebsiella-producing carbapenemase = 12, New Delhi metallo-ß-lactamase = 4, Verona integron-encoded metallo-ß-lactamase = 2). The most common infections were pneumonia (49.5%) and bacteraemia (30.3%). A decrease was found in median TAP (103 [IQR 76.0-156.0] vs. 75 [IQR 56-100] hours; P < 0.001). Median time from culture collection to final susceptibility results was shorter in the post-intervention group (123 vs. 93 hours; P < 0.001). CONCLUSION: This study identified improvement in TAP in MDR PsA and CRE infections with implementation of a reflex microbiology workflow and multidisciplinary antimicrobial stewardship initiatives.

Combined Use of RT-qPCR and NGS for Identification and Surveillance of SARS-CoV-2 Variants of Concern in Residual Clinical Laboratory Samples in Miami-Dade County, Florida.

Over the course of the COVID-19 pandemic, SARS-CoV-2 variants of concern (VOCs) with increased transmissibility and immune escape capabilities, such as Delta and Omicron, have triggered waves of new COVID-19 infections worldwide, and Omicron subvariants continue to represent a global health concern. Tracking the prevalence and dynamics of VOCs has clinical and epidemiological significance and is essential for modeling the progression and evolution of the COVID-19 pandemic. Next generation sequencing (NGS) is recognized as the gold standard for genomic characterization of SARS-CoV-2 variants, but it is labor and cost intensive and not amenable to rapid lineage identification. Here we describe a two-pronged approach for rapid, cost-effective surveillance of SARS-CoV-2 VOCs by combining reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) and periodic NGS with the ARTIC sequencing method. Variant surveillance by RT-qPCR included the commercially available TaqPath COVID-19 Combo Kit to track S-gene target failure (SGTF) associated with the spike protein deletion H69-V70, as well as two internally designed and validated RT-qPCR assays targeting two N-terminal-domain (NTD) spike gene deletions, NTD156-7 and NTD25-7. The NTD156-7 RT-qPCR assay facilitated tracking of the Delta variant, while the NTD25-7 RT-qPCR assay was used for tracking Omicron variants, including the BA.2, BA.4, and BA.5 lineages. In silico validation of the NTD156-7 and NTD25-7 primers and probes compared with publicly available SARS-CoV-2 genome databases showed low variability in regions corresponding to oligonucleotide binding sites. Similarly, in vitro validation with NGS-confirmed samples showed excellent correlation. RT-qPCR assays allow for near-real-time monitoring of circulating and emerging variants allowing for ongoing surveillance of variant dynamics in a local population. By performing periodic sequencing of variant surveillance by RT-qPCR methods, we were able to provide ongoing validation of the results obtained by RT-qPCR screening. Rapid SARS-CoV-2 variant identification and surveillance by this combined approach served to inform clinical decisions in a timely manner and permitted better utilization of sequencing resources.

Multisite Detection of Tn1549-Mediated vanB Vancomycin Resistance in Multidrug-Resistant Enterococcus faecalis ST6 in Texas and Florida.

In the United States, vanB-mediated resistance in enterococci is rare. We characterized three sequence type (ST) 6, vancomycin-resistant Enterococcus faecalis isolates causing bacteremia in unique patients in spatiotemporally distinct settings. Isolates were recovered between 2018 and 2020 in two cities in the United States (Houston, TX; Miami, FL). The isolates harbored the vanB operon on a chromosomally located Tn1549 transposon, and epidemiological data suggested multiple introductions of the vanB gene cluster into ST6 E. faecalis.

Rapid molecular testing for antimicrobial stewardship and solid organ transplantation.

BACKGROUND: Several molecular platforms now exist for early detection of infectious pathogens. In this review, we present the currently available literature summarizing clinical outcomes using rapid diagnostic tests (RDTs) in the solid organ transplant (SOT) population. We also present potential benefits and drawbacks of these technologies for SOT patients. METHODS: We completed a PubMed search querying for 31 specific RDTs AND ("SOT"). We also queried PubMed for studies on RDT outcomes in the general population. References of the resulting relevant studies were reviewed and incorporated if the study population included at least one SOT patient. All culture specimen types were included. Only full-text peer-reviewed publications in English were examined. RESULTS: Our search yielded eleven studies. Across these studies, integrating RDTs with ASP intervention led to faster species identification and susceptibility results, faster time-to-optimal therapy, decreased hospital length-of-stay and costs, and decreased mortality. Potential drawbacks of RDTs in the SOT population included: overdiagnosis due to increased sensitivity (i.e., Clostridium difficile), decreased yield of tests for respiratory pathogens, and lack of identification of important pathogens in this population such as, Aspergillus species. CONCLUSIONS: Although there is a scarcity of studies involving SOT patients, current available data suggests that the use of RDTs helps improve patient outcomes and minimizes inappropriate antimicrobial use when coupled with proactive ASPs. Future studies should focus on clinical outcomes in SOT patients specifically, as well as how to optimize the use of RDTs in conjunction with traditional microbiology methods.

Challenges and opportunities in stewardship among solid organ transplant recipients with Candida auris bloodstream infections.

BACKGROUND: Candida auris is an emerging nosocomial pathogen worldwide. However, there has been little published on the management of C. auris in solid organ transplant recipients. METHODS: A single-center, retrospective cohort study was conducted to evaluate C. auris bloodstream infections in solid organ transplant recipients between January 2020 and December 2021. Patient-related and outcomes data were extracted from electronic medical records. RESULTS: Of the 42 patients identified with C. auris bloodstream infections, five were in solid organ transplant recipients (1 heart, 3 liver, and 1 combined liver-kidney). The median time to fungemia from hospital admission was 43 days, and the median time to fungemia from transplant was 18 days. All patients received micafungin as initial treatment, at a median of 6 hours from pathogen detection. Four patients achieved blood clearance, two patients had persistent fungemia, and two patients developed secondary complications from hematogenous spread. One patient died, resulting in a mortality rate of 20%. CONCLUSIONS: Solid organ transplant recipients are at high risk for developing C. auris bloodstream infections. In order to prevent graft loss and mortality, best practices for the management of C.auris should include rapid screening, diagnosis, and treatment. While echinocandins are considered first-line, antifungal selection should be based on susceptibilities and site of infection. Data to support routine use of combination therapy are lacking, however there may be a role for refractory cases. Prevention efforts against C. auris infection are especially important given the lack of effective decolonization strategies. For transplant recipients, hospitals should seek opportunities to restore patients' gut microbiome by curtailing unnecessary hospital procedures and inappropriate antimicrobial use. Further research and national guidelines are needed to better direct stewardship in this field.

Is the Omicron variant truly less virulent in solid organ transplant recipients?

Solid organ transplant (SOT) recipients are at high risk for severe disease with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Emerging variants of concern have disproportionately affected this population. Data on severity and outcomes with the Omicron variant in SOT recipients are limited. Thus we conducted this single-center, retrospective cohort study of SOT recipients diagnosed with SARS-CoV-2 infection from December 18, 2021 to January 18, 2022, when prevalence of the Omicron variant was more than 80%-95% in the community. Univariate and multivariate logistic regression analysis was performed to identify risk factors for hospital admission. We identified 166 SOT patients: 112 (67.5%) kidney, 22 (13.3%) liver, 10 (6.0%) lung, seven (4.2%) heart, and 15 (9.0%) combined transplants. SARS-CoV-2 vaccine series was completed in 59 (35.5%) recipients. Ninety-nine (59.6%) and 13 (7.8%) recipients received casirivimab/imdevimab and sotrovimab, respectively. Fifty-three (32%) recipients required hospital admission, of which 19 (35.8%) required intensive care unit level of care. Median follow-up was 50 (interquartile range, 25-59) days, with mortality reported in six (3.6%) patients. Risk factors identified for hospital admission were African American race (p < .001, odds ratio [OR] 4.00, 95% confidence interval [CI] 1.84-8.70), history of coronary artery disease (p = .031, OR 3.50, 95% CI 1.12-10.87), and maintenance immunosuppression with corticosteroids (p = .048, OR 2.00, 95% CI 1.01-4.00). In conclusion, contrary to that in the general population, we found a higher hospital admission rate in SOT recipients with omicron variant infection. Further studies to investigate the efficacy of newer treatments are necessary, even as outcomes continue to improve.

Mycobacterium abscessus Infections in Solid Organ Transplant Recipients: Single-Center Experience in the United States, 2013-2018.

Background: Mycobacterium abscessus is increasingly recognized as a human pathogen causing life-threatening infections in immunocompromised patients. There is a paucity of data around this topic in solid organ transplant (SOT) recipients. Methods: This work was a single-center retrospective cohort study of all SOT recipients with a positive culture for M abscessus between 2013 and 2018. Results: A total of 20 patients (55% female) met inclusion criteria, including 1 kidney recipient (5.0%), 2 liver recipients (10.0%), 12 lung recipients (60.0%), 1 heart recipient (5.0%), and 4 combined organ recipients (20.0%). The median time from SOT to infection was 100 days (range, 30-431 days). Thirteen (65.0%) patients (1 kidney, 1 heart, 7 lung, 1 liver, 1 intestine, and 2 multivisceral) were treated with a median duration of 185 antibiotic days (range, 20-523 days). Among them, M abscessus was isolated from respiratory samples in 8 and nonrespiratory samples in 5; 4 of 13 (30.8%) patients had treatment failure and 3 of 13 (23.1%) had unrelated deaths within 1 year after diagnosis. Seven patients (5 lung transplant recipients) with the organism isolated from respiratory samples were not treated as their cultures represented airway colonization or contamination; of those, 2 (28.6%) died (unrelated to infection) and 5 (71.4%) were alive without the infection after 1 year of follow-up. Conclusions: Mycobacterium abscessus infections affect SOT recipients with a high proportion of clinical failures. However, in lung recipients, not all positive cultures correlated with infection, and without treatment some patients had good clinical outcomes. Thus, differentiating colonization from infection is important, and infection prevention measures and novel therapeutic agents are needed for SOT recipients.