Extending duration of letermovir prophylaxis in haploidentical stem cell transplantation.

Not available.

A Retrospective, Observational Study of 12 Cases of Expanded-Access Customized Phage Therapy: Production, Characteristics, and Clinical Outcomes.

BACKGROUND: Antimicrobial resistance (AMR) is undermining modern medicine, a problem compounded by bacterial adaptation to antibiotic pressures. Phages are viruses that infect bacteria. Their diversity and evolvability offer the prospect of their use as a therapeutic solution. Reported are outcomes of customized phage therapy for patients with difficult-to-treat antimicrobial resistant infections. METHODS: We retrospectively assessed 12 cases of customized phage therapy from a phage production center. Phages were screened, purified, sequenced, characterized, and Food and Drug Administration-approved via the IND (investigational new drug) compassionate-care route. Outcomes were assessed as favorable or unfavorable by microbiologic and clinical standards. Infections were device-related or systemic. Other experiences such as time to treatment, antibiotic synergy, and immune responses were recorded. RESULTS: Fifty requests for phage therapy were received. Customized phages were generated for 12 patients. After treatment, 42% (5/12) of cases showed bacterial eradication and 58% (7/12) showed clinical improvement, with two-thirds of all cases (66%) showing favorable responses. No major adverse reactions were observed. Antibiotic-phage synergy in vitro was observed in most cases. Immunological neutralization of phages was reported in 5 cases. Several cases were complicated by secondary infections. Complete characterization of the phages (morphology, genomics, and activity) and their production (methods, sterility, and endotoxin tests) are reported. CONCLUSIONS: Customized phage production and therapy was safe and yielded favorable clinical or microbiological outcomes in two-thirds of cases. A center or pipeline dedicated to tailoring the phages against a patient's specific AMR bacterial infection may be a viable option where standard treatment has failed.

Strategies to Mitigate the Drug-Drug Interaction between Nirmatrelvir/Ritonavir and Tacrolimus in Allogeneic Hematopoietic Stem Cell Transplant Recipients on Azole Antifungals: Results of a Case Series.

INTRODUCTION: Nirmatrelvir/ritonavir (NIM/r) inhibits tacrolimus metabolism resulting in a profound drug-drug interaction that is further complicated by the use of azole antifungals. CASE PRESENTATIONS: We describe three strategies, in 4 patient cases, for the initiation of NIM/r in allogeneic hematopoietic stem cell transplant (alloHSCT) recipients on tacrolimus at the time of diagnosis. Patients 1 and 2 (strategy 1) experienced prolonged, elevated tacrolimus concentrations after an empiric 33% reduction in tacrolimus dose and adjustment of azole antifungal at NIM/r initiation (strategy 1) and with complete discontinuation of tacrolimus and azole antifungal at NIM/r initiation (strategy 2). Patients 3 and 4 (strategy 3) did not experience elevated tacrolimus concentrations on NIM/r treatment with complete discontinuation of tacrolimus and azole antifungal and a 12-24-h delay in NIM/r initiation. Reinitiation of tacrolimus after NIM/r completion resulted in variable tacrolimus concentrations. CONCLUSION: NIM/r-tacrolimus is a serious drug-drug interaction which can be mitigated by early discontinuation of tacrolimus and azole antifungals, close monitoring, and reinitiation of tacrolimus and antifungal 48-72 h after completion of therapy.

Extrapulmonary manifestations of severe acute respiratory syndrome coronavirus-2 infection.

Coronavirus disease 2019, the infectious disease caused by severe acute respiratory syndrome coronavirus-2, has resulted in a global pandemic with unprecedented health, societal, and economic impact. The disease often manifests with flu-like symptoms and is dominated by pulmonary complications, but widely diverse clinical manifestations involving multiple organ systems can result. We posit that viral tropism and the aberrant host immune response mediate the protean findings and severity in this disease. In general, extrapulmonary manifestations are a harbinger of or contemporaneously associate with disease progression, but in the case of some extrapulmonary findings (gastrointestinal and dermatologic), may track with milder disease. The precise underlying pathophysiological mechanisms remain incompletely elucidated, and additional immune phenotyping studies are warranted to reveal early correlates of disease outcomes and novel therapeutic targets.

Multidrug-resistant bacteria in lung transplantation.

PURPOSE OF REVIEW: The review of infections in lung transplantation is beyond the scope of this article as it is a comprehensive topic, however we aim to focus on infections with multidrug-resistant (MDR) microorganisms in this patient population. RECENT FINDINGS: New emerging clinical studies have provided data regarding outcomes in lung transplant recipients with MDR bacterial infections. SUMMARY: Isolation of MDR bacteria from lung donors preoperatively has not been associated with worse outcomes in recipients. Patients with cystic fibrosis colonized with MDR bacteria do not have increased 1 year mortality rates compared to those without MDR bacteria.

VRE in cirrhotic patients.

BACKGROUND: Vancomycin resistant enterococci (VRE) infections are of increasing concern in many hospitalized patients. Patients with cirrhosis are at added risk of infection with VRE, with associated increased risk for complications from infections. The goals of this study were to: [1] identify risk factors for VRE amongst cirrhotic patients before liver transplantation, and [2] evaluate risk of morbidity and mortality at 30-days and one-year after VRE infection. METHODS: Chart review of 533 cirrhotic patients hospitalized at a tertiary medical center was performed. Patients infected with VRE (n = 65) were separately compared to patients infected with gram-negative organisms (n = 80) and uninfected patients (n = 306). RESULTS: In multivariable logistic regression analyses, female gender (OR 3.73(95% CI1.64,8.49)), severity of liver disease measured by higher Child Pugh scores (OR 0.37(95%CI 0.16,0.84)), presence of ascites (OR 9.43(95% CI 3.22,27.65) and any type of dialysis (OR 3.31,95% CI (1.21,9.04), oral antibiotic prophylaxis for spontaneous bacterial peritonitis and rifaximin use were statistically significantly associated with VRE infection (OR 2.37 (95%CI 1.27, 4.42)). VRE-infected patients had significantly longer mean ICU and total hospital stays (both p < 0.0001), with increased one-year mortality compared to cirrhotic patients without VRE infection, adjusted for age, sex, Hispanic ethnicity, and disease severity. CONCLUSIONS: It is unclear whether VRE infection serves as an independent risk factor for increased mortality or an indicator for patients with more severe illnesses and thus a higher risk for death.

Community-acquired respiratory viruses.

PURPOSE OF REVIEW: Community-acquired respiratory viruses (CARV) have been historically linked to upper respiratory tract infections; however, new data has emerged in recent years that has provided new insight into their role as causative pathogens for lower respiratory tract infections. We aim to discuss the importance of recognition of viruses both epidemiologically and clinically as causes of lower respiratory tract infection. RECENT FINDINGS: With advances of molecular testing it is now possible to identify viruses from clinical specimens which have many implications that range from therapeutics to antibiotic stewardship. Recent studies suggest that most of the cases of community-acquired pneumonia are caused by viruses, which corresponds to a paradigm shift for most clinicians. SUMMARY: As community-acquired lower respiratory infections are the most common cause of ICU admission in the USA, it is important for medical providers to be aware of the association with viruses, especially in patients with immunosuppression because of solid organ transplant and hematologic malignancies when sometimes diagnosis can be challenging and patients can be exposed to unnecessary antibiotics.

Coccidioidomycosis in solid organ transplant recipients.

PURPOSE OF REVIEW: The purpose of the review is an update of diagnosis and treatment of coccidioidomycosis infection in solid organ transplant (SOT) patients. Endemic fungal infections continue to be a cause of serious morbidity and mortality in transplant recipients. RECENT FINDINGS: In transplant patients there are recommendations regarding screening in areas that are endemic for coccidioidomycosis. This screening involves serologic testing and chest imaging. In endemic areas pretransplant seropositivity varies from 1.4 to 5.6%. In immunocompromised patients with elevated complement fixation titers, evaluation of cerebrospinal fluid is recommended even in the absence of symptoms. Although coccidioidomycosis can be a self-limited disease in immunocompotent patients, all SOT patients should be treated regardless of severity. This may include intravenous amphotericin B in severe cases and fluconazole therapy in milder episodes. In those SOT recipients with evidence of prior coccidioidomycosis, lifelong secondary prophylaxis with fluconazole given risk of recurrent disease. SUMMARY: Coccidioidomycosis continues to be a cause of serious morbidity and mortality in transplant recipients but with proper screening and treatment can be successfully managed.

Cryptococcal disease in the solid organ transplant setting: review of clinical aspects with a discussion of asymptomatic cryptococcal antigenemia.

PURPOSE OF REVIEW: Cryptococcal infections are an important cause of morbidity and mortality in solid organ transplant patients. Here, we review the microbiology, epidemiology, clinical course, treatment, and outcomes of Cryptococcus in solid organ transplant recipients. RECENT FINDINGS: We identify the unique findings in solid organ transplant patients when compared to other immunocompromised patients such as those with HIV. We also describe our experience and outcomes with regard to solid organ transplant patients who do not have positive fungal cultures, but cryptococcal antigen positivity and concern for cryptococcal disease. SUMMARY: Our review will highlight the importance of these new diagnostic techniques in those with Cryptococcus and solid organ transplant, which will be the subject of new research.

Persistent Impairment in Immune Reconstitution and Worse Survival Outcomes in Allogeneic Stem Cell Transplantation Patients with Early Coronavirus Disease 2019 Infection.

Patients undergoing allogenic hematopoietic stem cell transplantation (HSCT) are at an increased risk of mortality due to transplantation-related complications in the first year post-transplantation, owing in part to the profound immune dysregulation with T cell and B cell lymphopenia and functional impairment. Although several large studies have reported higher mortality rates from Coronavirus disease 2019 (COVID-19) in HSCT recipients, to date no study has focused on the impact of early COVID-19 infection on immune reconstitution post-transplantation and the correlation with transplantation outcomes. We retrospectively analyzed 61 consecutive adult patients who underwent their first allogeneic HSCT at our institution. Thirteen patients (21.3%) experienced early COVID-19 infection, with a median time to diagnosis of 100 days post-transplantation. In multivariable analysis, patients with early COVID-19 infection had significantly worse overall survival (adjusted hazard ratio [aHR], 4.06; 95% confidence interval [CI], 1.26 to 13.05; P = .019) and progression-free survival (aHR, 6.68; 95% CI, 2.11 to 21.11; P = .001). This was attributed mainly to higher nonrelapse mortality (NRM) among early COVID-19 patients (P = .042). Allogeneic HSCT recipients with early COVID-19 infection had significant delays in absolute lymphocyte count (95% CI, -703.69 to -56.79; P = .021), CD3+CD4+ cell (95% CI, -105.35 to -11.59; P = .042), CD3+CD8+ cell (95% CI, -324.55 to -57.13; P = .038), and CD3-CD56+ cell (95% CI, -193.51 to -47.31; P = .014) recovery compared to those without early COVID-19 infection. Our findings suggest that patients with early COVID-19 infection after allogeneic HSCT have higher NRM and worse survival, at least in part due to impaired immune reconstitution post-transplantation.

Validation of SeptiCyte RAPID to Discriminate Sepsis from Non-Infectious Systemic Inflammation.

(1) Background: SeptiCyte RAPID is a molecular test for discriminating sepsis from non-infectious systemic inflammation, and for estimating sepsis probabilities. The objective of this study was the clinical validation of SeptiCyte RAPID, based on testing retrospectively banked and prospectively collected patient samples. (2) Methods: The cartridge-based SeptiCyte RAPID test accepts a PAXgene blood RNA sample and provides sample-to-answer processing in ~1 h. The test output (SeptiScore, range 0-15) falls into four interpretation bands, with higher scores indicating higher probabilities of sepsis. Retrospective (N = 356) and prospective (N = 63) samples were tested from adult patients in ICU who either had the systemic inflammatory response syndrome (SIRS), or were suspected of having/diagnosed with sepsis. Patients were clinically evaluated by a panel of three expert physicians blinded to the SeptiCyte test results. Results were interpreted under either the Sepsis-2 or Sepsis-3 framework. (3) Results: Under the Sepsis-2 framework, SeptiCyte RAPID performance for the combined retrospective and prospective cohorts had Areas Under the ROC Curve (AUCs) ranging from 0.82 to 0.85, a negative predictive value of 0.91 (sensitivity 0.94) for SeptiScore Band 1 (score range 0.1-5.0; lowest risk of sepsis), and a positive predictive value of 0.81 (specificity 0.90) for SeptiScore Band 4 (score range 7.4-15; highest risk of sepsis). Performance estimates for the prospective cohort ranged from AUC 0.86-0.95. For physician-adjudicated sepsis cases that were blood culture (+) or blood, urine culture (+)(+), 43/48 (90%) of SeptiCyte scores fell in Bands 3 or 4. In multivariable analysis with up to 14 additional clinical variables, SeptiScore was the most important variable for sepsis diagnosis. A comparable performance was obtained for the majority of patients reanalyzed under the Sepsis-3 definition, although a subgroup of 16 patients was identified that was called septic under Sepsis-2 but not under Sepsis-3. (4) Conclusions: This study validates SeptiCyte RAPID for estimating sepsis probability, under both the Sepsis-2 and Sepsis-3 frameworks, for hospitalized patients on their first day of ICU admission.

Rapid and Robust Identification of Sepsis Using SeptiCyte RAPID in a Heterogeneous Patient Population.

Background/Objective: SeptiCyte RAPID is a transcriptional host response assay that discriminates between sepsis and non-infectious systemic inflammation (SIRS) with a one-hour turnaround time. The overall performance of this test in a cohort of 419 patients has recently been described [Balk et al., J Clin Med 2024, 13, 1194]. In this study, we present the results from a detailed stratification analysis in which SeptiCyte RAPID performance was evaluated in the same cohort across patient groups and subgroups encompassing different demographics, comorbidities and disease, sources and types of pathogens, interventional treatments, and clinically defined phenotypes. The aims were to identify variables that might affect the ability of SeptiCyte RAPID to discriminate between sepsis and SIRS and to determine if any patient subgroups appeared to present a diagnostic challenge for the test. Methods: (1) Subgroup analysis, with subgroups defined by individual demographic or clinical variables, using conventional statistical comparison tests. (2) Principal component analysis and k-means clustering analysis to investigate phenotypic subgroups defined by unique combinations of demographic and clinical variables. Results: No significant differences in SeptiCyte RAPID performance were observed between most groups and subgroups. One notable exception involved an enhanced SeptiCyte RAPID performance for a phenotypic subgroup defined by a combination of clinical variables suggesting a septic shock response. Conclusions: We conclude that for this patient cohort, SeptiCyte RAPID performance was largely unaffected by key variables associated with heterogeneity in patients suspected of sepsis.

Once-Daily Foscarnet Is Effective for Human Herpesvirus 6 Reactivation after Hematopoietic Stem Cell Transplantation.

Human herpesvirus 6 (HHV-6) reactivation is common after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with higher mortality and increased transplantation-related complications. We hypothesized that preemptive treatment with a short course of foscarnet at a lower cutpoint of plasma HHV-6 viral load would be effective in treating early HHV-6 reactivation, preventing complications and precluding hospitalization of these patients. We reviewed outcomes of adult patients (age ≥18 years) who received preemptive treatment with once-daily foscarnet 60 to 90 mg/kg for 7 days for HHV-6 reactivation after allo-HSCT at our institution between May 2020 and November 2022. Plasma HHV-6 viral load was monitored by quantitative PCR twice monthly in the first 100 days post-transplantation and twice weekly after reactivation until resolution. Eleven patients with a median age of 46 years (range, 23 to 73 years) were included in the analysis. HSCT was performed with a haploidentical donor in 10 patients and with an HLA-matched related donor in 1 patient. The most common diagnosis was acute leukemia (9 patients). Myeloablative and reduced-intensity conditioning regimens were used in 4 and 7 patients, respectively. Ten of the 11 patients received post-transplantation cyclophosphamide-based graft-versus-host disease prophylaxis. The median follow-up was 440 days (range, 174 to 831 days), and the median time to HHV-6 reactivation was 22 days post-transplantation (range, 15 to 89 days). The median viral load at first reactivation was 3,100 copies/mL (range, 210 to 118,000 copies/mL), and the median peak viral load was 11,300 copies/mL (range, 600 to 983,000 copies/mL). All patients received a short course of foscarnet at either 90 mg/kg/day (n = 7) or 60 mg/kg/day (n = 4). In all patients, plasma HHV-6 DNA was undetectable at completion of 1 week of treatment. No HHV-6 encephalitis or pneumonitis occurred. All patients achieved neutrophil and platelet engraftment after a median of 16 days (range, 8 to 22 days) and 26 days (range, 14 to 168 days), respectively, with no secondary graft failure. No complications related to foscarnet administration were noted. One patient with very high HHV-6 viremia had recurrent reactivation and received a second course of foscarnet as an outpatient. A short course of once-daily foscarnet is effective in treating early HHV-6 reactivation post-transplantation and may reduce the incidence of HHV-6-related and treatment-related complications and preclude hospitalization in these patients.

A Programmatic Response, Including Bamlanivimab or Casirivimab-imdevimab Administration, Reduces Hospitalization and Death in COVID-19 Positive Abdominal Transplant Recipients.

BACKGROUND: (COVID-19) has resulted in significant morbidity and mortality in solid organ transplant recipients. In December 2020, at the peak of the Los Angeles outbreak, our center rapidly implemented a protocol to improve outpatient management and provide bamlanivimab or casirivimab-imdevimab [COVID monoclonal antibody (mAb) therapies] to all eligible COVID-19 positive liver and kidney transplant recipients. METHODS: A retrospective review of all abdominal organ transplant recipients who were COVID-19 polymerase chain reaction positive between February 2020 and February 2021 from our center was performed. Patient demographics, COVID-19 treatments, hospitalizations, and survival were reviewed. Patients were considered eligible for COVID mAb therapy if they met outpatient criteria at the time of diagnosis. RESULTS: In the study period, 121 patients in the kidney transplant recipients group (KG) and 105 patients in the liver or combined liver/kidney transplant recipients group (LG) were COVID-19 polymerase chain reaction positive. Hospitalization rates were similar for the KG (45%) versus LG (35%) (P = 0.20), but mortality was higher for the KG (22%) when compared to LG (10%) (P = 0.02). Our programmatic response, including outpatient COVID mAb therapies, reduced hospitalizations (P = 0.01) and deaths (P = 0.01). Ninety-four KG and 87 LG patients were identified as potentially eligible for COVID mAb therapy, and 17 KG and 17 LG patients were treated. COVID mAb therapies reduced hospitalization from 32% to 15% (P = 0.045) and eliminated mortality (13% versus 0%, P = 0.04). CONCLUSIONS: An aggressive approach including outpatient COVID mAb therapy in the COVID positive abdominal organ transplant recipients significantly decreased hospitalization and death. Early outpatient intervention for COVID-19 disease in transplant patients should be considered where possible.

Association of Presenting Symptoms With Abnormal Laboratory Values for Vector-Borne Illness - Experience in an Urban Gastroenterology Practice.

PURPOSE: In the clinical setting, it is not common practice to consider a vector bite, such as from a tick or flea, to be a contributing factor to chronic digestive symptoms. This article investigates associations we have observed among symptomatic patients and positive blood tests for vector-borne illness (VBI). METHODS: Patients who visited an urban gastroenterology clinic over a 3-year period were retrospectively reviewed. A total of 270 patients presenting with a constellation of digestive symptoms - and who had no apparent digestive pathology and reported no prior diagnosis or treatments for VBI - were analyzed. Before the initial visit, all patients completed a review of systems medical history form, which comprised 19 gastrointestinal (GI) symptoms and 73 non-GI-related symptoms and conditions. Patients were tested for small intestinal bacterial overgrowth (SIBO) by lactulose breath test. VBI (babesiosis, ehrlichiosis, anaplasmosis, bartonellosis, borreliosis) was established using 1 or more of several blood tests. Odds ratio (OR) analysis determined associations between exposure to VBI, SIBO, and presenting symptoms/conditions. Two age groups (≤35 years and ≥36 years) were studied using Cochran-Mantel-Haenszel stratum-based test. RESULTS: A higher OR (2.03, 95% CI: 1.5-3.6) was found between patients with ≥3 digestive symptoms and positive blood tests for ≥1 VBI. Five of the 19 GI symptoms were independently associated with VBI-positive samples: food intolerance, indigestion, nausea/vomiting, constipation, and heartburn. A similar association in patients with ≥3 non-GI symptoms (OR: 2.83, 95% CI: 1.3-6.4) was observed. Five of the 73 non-GI symptoms/conditions were independently associated with VBI-positive samples: chest pain, shortness of breath, extremity or joint pain, anxiety, and night sweats. Having ≥3 of any digestive or nondigestive symptoms generated significant relative risk of being VBI-positive. Presence of SIBO alone did not identify significant relative risk for a VBI, and age was not a confounder. CONCLUSIONS: Findings revealed an association between positive blood tests for vector-borne illness and chronically symptomatic patients regardless of whether symptoms were digestive or nondigestive. The manifestation of 3 or more gastrointestinal and/or extraintestinal symptoms should raise suspicion for a VBI.

Remdesivir for the Treatment of COVID-19: A Systematic Review of the Literature.

In March 2020, the World Health Organization declared the spread of SARS-CoV-2 a global pandemic. To date, coronavirus disease-2019 (COVID-19) has spread to over 200 countries, leading to over 1.6 million cases and over 99,000 deaths. Given that there is neither a vaccine nor proven treatment for COVID-19, there is currently an urgent need for effective pharmacotherapy. To address the need for an effective treatment of SARS-CoV-2 during the worldwide pandemic, this systematic review of intravenous (IV) remdesivir was performed. Remdesivir, an anti-viral prodrug originally developed to treat Ebola virus disease, has shown broad spectrum activity against the Coronavirus family. A recent case report reported improvement of clinical symptoms with remdesivir in a patient with COVID-19. After conducting a systematic search of 18 clinical trial registries and three large scientific databases, we identified 86 potentially eligible items. Following removal of duplicates (n = 21), eligible studies were reviewed independently by two authors. After the first round of screening, inter-rater agreement was 98.5% (κ = 0.925). After the second round of full-text screening, inter-rater agreement was 100%. A total of seven ongoing and recruiting clinical trials of remdesivir (100-200 milligrams, intravenous [IV]) were included. We identified the following primary outcomes: patients discharged (n = 2); time to clinical status improvement (n = 2); improved O2 saturation (n = 2); body temperature normalization (n = 2); and clinical status (n = 1). Secondary outcomes in all identified studies included documentation of adverse events. Phase 3 trials are expected to be completed between April 2020-2023. Therefore, despite supportive data from in vitro and in vivo studies, the clinical effectiveness of IV remdesivir for treatment of COVID-19 and potential side effects remain incompletely defined in the human population.

Increased risk of 100-day and 1-year infection-related mortality and complications in haploidentical stem cell transplantation.

Background: While haploidentical transplantation has led to the near-universal availability of donors, several challenges for this form of transplant still exist. This study sought to investigate the rates of infection-related mortality and other complications following haploidentical vs nonhaploidentical transplant. Methods: We conducted a retrospective cohort study in adults with various malignant and benign hematological conditions who underwent allogeneic hematopoietic stem cell transplantation from 2011 to 2018. One hundred-day and 1-year overall survival were defined as survival from the time of transplant until 100 days or 1 year later. Results: A total of 187 patients were included in this study, with 45 (24.1%) receiving transplants from haploidentical donors and 142 (75.9%) from nonhaploidentical donors. There were similar rates of acute graft-versus-host disease (GVHD) (40% vs 38% in haploidentical vs nonhaploidentical recipients, P=0.86) and chronic GVHD (44.4% vs 43.7%, P=1). Rates of 100-day and 1-year infection-related mortality were significantly higher in the haploidentical group compared to the nonhaploidentical group (8.9% vs 1.4% at 100 days, P=0.03, and 15.9% vs 3.8% at 1 year, P=0.01). There were also higher rates of cytomegalovirus infections (59.1% vs 23.8%, P<0.01), BK virus-associated hemorrhagic cystitis (40.9% vs 8.4%, P<0.01), and BK viremia (15.9% vs 0.8%, P<0.01) in haploidentical recipients. Conclusions: Despite the use of identical antimicrobial prophylactic and treatment agents, haploidentical recipients were found to have significantly increased rates of 100-day and 1-year infection-related mortality as well as several other infectious complications.

Relationship between microbial translocation and endothelial function in HIV infected patients.

BACKGROUND: Circulating levels of microbial products are increased in HIV infection, and provoke endothelial dysfunction in other disease settings. METHODOLOGY/PRINCIPAL FINDINGS: We examined data from a cross-sectional single site study at Indiana University (Indiana, N = 85) and a 24- week multicenter prospective study of antiretroviral therapy (ART) initiation (ACTG 5152s, N = 75). Brachial artery flow-mediated dilation (FMD) was measured by ultrasound. Plasma lipopolysaccharide (LPS) and soluble CD14 (sCD14) levels were measured from stored specimens and correlated with FMD values using Pearson correlations. The Indiana subjects were 63% male with a mean age of 39 years and a median CD4 count of 406 cells/mm(3) (388 not on ART, 464 on ART). The 5152s subjects were 92% were male with a mean age of 35 years and a median CD4 count of 251 cells/mm(3) at entry which increased to 396 cells/mm(3) on ART. When analyzing the two cohorts individually or in combination neither sCD14 nor LPS correlated significantly with FMD. In a pre-specified subgroup analysis of the Indiana subjects receiving ART (N = 46, mean ART duration 40 months) LPS was inversely correlated with FMD (r = -0.33, p = 0.02), but not sCD14 (r = -0.01, p = 0.9). Multivariate analysis confirmed LPS as an independent predictor of FMD in this subgroup (p = 0.02). CONCLUSIONS/SIGNIFICANCE: In HIV-infected individuals on prolonged ART, higher LPS levels are associated with worse endothelial function but not in untreated subjects or at 24 weeks after ART initiation. Persistent microbial translocation may contribute to arterial dysfunction and the increased cardiovascular disease risk observed in individuals on long-term ART.