Clinical Utility of Plasma Microbial Cell-Free DNA Sequencing Among Immunocompromised Patients With Pneumonia.

Background: Plasma microbial cell-free DNA (mcfDNA) sequencing can establish the etiology of multiple infectious syndromes by identifying microbial DNA in plasma. However, data are needed to define the clinical scenarios where this tool offers the highest clinical benefit. Methods: We conducted a prospective multicenter observational study that evaluated the impact of plasma mcfDNA sequencing compared with usual care testing among adults with hematologic malignancies. This is a secondary analysis of an expanded cohort that evaluated the clinical utility of plasma mcfDNA sequencing across prespecified and adjudicated outcomes. We examined the percentage of participants for whom plasma mcfDNA sequencing identified a probable cause of pneumonia or clinically relevant nonpneumonia infection. We then assessed potential changes in antimicrobial therapy based on plasma mcfDNA sequencing results and the potential for early mcfDNA testing to avoid bronchoscopy and its associated adverse events. Results: Of 223 participants, at least 1 microbial detection by plasma mcfDNA sequencing was adjudicated as a probable cause of pneumonia in 57 (25.6%) and a clinically relevant nonpneumonia infection in 88 (39.5%). A probable cause of pneumonia was exclusively identified by plasma mcfDNA sequencing in 23 (10.3%) participants. Antimicrobial therapy would have changed for 41 (18.4%) participants had plasma mcfDNA results been available in real time. Among the 57 participants with a probable cause of pneumonia identified by plasma mcfDNA sequencing, bronchoscopy identified no additional probable cause of pneumonia in 52 (91.2%). Conclusions: Plasma mcfDNA sequencing could improve management of both pneumonia and other concurrent infections in immunocompromised patients with suspected pneumonia.

Plasma Microbial Cell-Free DNA Sequencing in Immunocompromised Patients With Pneumonia: A Prospective Observational Study.

BACKGROUND: Pneumonia is a common cause of morbidity and mortality, yet a causative pathogen is identified in a minority of cases. Plasma microbial cell-free DNA sequencing may improve diagnostic yield in immunocompromised patients with pneumonia. METHODS: In this prospective, multicenter, observational study of immunocompromised adults undergoing bronchoscopy to establish a pneumonia etiology, plasma microbial cell-free DNA sequencing was compared to standardized usual care testing. Pneumonia etiology was adjudicated by a blinded independent committee. The primary outcome, additive diagnostic value, was assessed in the Per Protocol population (patients with complete testing results and no major protocol deviations) and defined as the percent of patients with an etiology of pneumonia exclusively identified by plasma microbial cell-free DNA sequencing. Clinical additive diagnostic value was assessed in the Per Protocol subgroup with negative usual care testing. RESULTS: Of 257 patients, 173 met Per Protocol criteria. A pneumonia etiology was identified by usual care in 52/173 (30.1%), plasma microbial cell-free DNA sequencing in 49/173 (28.3%) and the combination of both in 73/173 (42.2%) patients. Plasma microbial cell-free DNA sequencing exclusively identified an etiology of pneumonia in 21/173 patients (additive diagnostic value 12.1%, 95% confidence interval [CI], 7.7% to 18.0%, P < .001). In the Per Protocol subgroup with negative usual care testing, plasma microbial cell-free DNA sequencing identified a pneumonia etiology in 21/121 patients (clinical additive diagnostic value 17.4%, 95% CI, 11.1% to 25.3%). CONCLUSIONS: Non-invasive plasma microbial cell-free DNA sequencing significantly increased diagnostic yield in immunocompromised patients with pneumonia undergoing bronchoscopy and extensive microbiologic and molecular testing. CLINICAL TRIALS REGISTRATION: NCT04047719.

The Danish-American Research Exchange (DARE): a cross-sectional study of a binational research education program.

BACKGROUND: Most medical educational programs emphasize clinical observation or clinical skill acquisition, fewer focus upon research. The Danish-American Research Exchange (DARE) program, sponsored by the Lundbeck Foundation, is unique in that the medical student initiates biomedical research collaboration between Danish and US medical institutions. To achieve this, Danish medical students (DARE students) conduct binational mentored research projects while based in the United States for 10 months. In addition, DARE students are introduced to interdisciplinary thinking about how to develop ultra-low-cost healthcare interventions through the '$10 Challenge'. METHODS: We conducted a cross-sectional study of DARE alumni over five consecutive years (2015-2020, n = 24). Research metrics included completion of a research project, primary authorship, and co-authorship of publications. The number of publications, prior to and after the DARE program were enumerated. For the first four cohorts, graduation from medical school and acceptance or intention to enter a joint MD-PhD program also were assessed. Two focus groups were conducted using constructivist grounded theory. Discussions were transcribed, redacted, and coded using Dedoose software. RESULTS: DARE Medical students were 31.2 years (range 24-35), the majority were women (67%;16/24). The majority (17/24;71%) completed a first author publication in a peer-reviewed journal with a median of 3.9 per DARE alumnus. DARE alumnus reported increased proficiency in biostatistics, epidemiology, coding and public speaking as well as stronger research qualities in creativity, critical thinking, comfort in approaching scientist in both the US and Denmark (p < 0.001 for all). Qualitative key themes included: increased confidence, a deepening of research inquiry and linkage to a research network. CONCLUSIONS: Preliminarily, this study suggests that medical students can initiate binational collaboration in medicine. Benefits include research productivity, intention to pursue academic medical careers, as well as positive impacts on motivation. This medical student-initiated research model lays the groundwork for using this model across other country pairs to promote binational collaboration.

TNF-α inhibition in the setting of undiagnosed HIV infection: a call for enhanced screening guidelines.

BACKGROUND: Despite the risks of immunosuppression, recommendations regarding screening for HIV infection prior to initiation of biologic therapies targeting common rheumatologic disorders, including inflammatory bowel disease (IBD) and inflammatory arthritides, are limited. Few cases of patients started on biologics while living with undiagnosed HIV infection have been reported. METHODS: We report three cases of patients initiated on biologics in the absence of recent or concurrent HIV screening who developed refractory disease or unanticipated complications and were later found to have undiagnosed chronic HIV infection. RESULTS: In Case 1, a 53-year-old MSM with negative HIV testing 2 years prior presented with presumed rheumatoid arthritis. He did not respond to methotrexate, so adalimumab was started. HIV testing to evaluate persistent symptoms was positive 9 months later; CD4+ T-cell count was 800 cells/µl. Antiretroviral therapy (ART) resulted in resolution of symptoms, which were attributed to HIV-associated arthropathy. In Case 2, a 55-year-old woman with injection drug use in remission and no prior HIV testing presented with hidradenitis suppurativa. She started infliximab and methotrexate therapy with good response. After she developed weight loss and lymphopenia, an HIV test was positive; CD4+ T-cell count was 334 cells/µl. Biologic hidradenitis suppurativa therapy was discontinued, with subsequent poor hidradenitis suppurativa control. In Case 3, a 32-year-old MSM with no prior HIV testing presented with presumed IBD; infliximab and steroids were started. Symptoms progressed despite IBD-directed therapy, and he was diagnosed with extensive Kaposi sarcoma with visceral and cutaneous involvement, likely exacerbated by immunosuppression. HIV testing was positive; CD4+ T-cell count was 250 cells/µl. Kaposi sarcoma initially worsened due to ART-associated immune reconstitution inflammatory syndrome. He is now improving with systemic chemotherapy and ART. HIV-associated Kaposi sarcoma is presumed to be the underlying diagnosis. CONCLUSION: All three patients had elevated risk for HIV infection, and two had final diagnoses attributed to chronic HIV infection, not warranting therapeutic immunosuppression. Screening for HIV infection prior to initiation of biologic therapy should be incorporated into clinical practice guidelines.

Opportunistic coinfection with Pneumocystis jirovecii and Coccidioides immitis associated with idelalisib treatment in a patient with chronic lymphocytic leukaemia.

We describe a case of opportunistic coinfections with Coccidioides immitis and Pneumocystis jirovecii following treatment with idelalisib, a phosphoinositide 3-kinase inhibitor, for chronic lymphocytic leukaemia. This is the first case of pulmonary coccidioidomycosis reported in association with idelalisib. We review challenges related to diagnosis of opportunistic infections in this context. This report illustrates (1) the uncommon occurrence of two opportunistic infections concurrently or in rapid succession, (2) the importance of maintaining a broad differential diagnosis in the setting of an atypical imaging finding, slow clinical response or when immunomodulatory drugs are used, and (3) the challenges associated with non-invasive serological testing in individuals with haematological malignancy on immunomodulatory therapy.

Outcomes of immunomodulatory and biologic therapy in people living with HIV.

OBJECTIVES: Immunomodulatory drugs (IMDs) are crucial for treating autoimmune, inflammatory, and oncologic conditions. Data regarding the safety of IMDs in people living with HIV (PLWH) are limited. We describe outcomes in all PLWH prescribed these agents from 2000--2019 at two academic medical centers. DESIGN: Retrospective cohort study. METHODS: We systematically identified and reviewed charts of all PLWH receiving IMDs. We defined a treatment episode as an uninterrupted period on an IMD regimen. We quantified infections, blips (detectable plasma HIV RNA following an undetectable result), and virologic failure (progression from plasma HIV RNA <200 copies/ml to two consecutive values >200 copies/ml despite ART). RESULTS: Seventy-seven patients contributed 110 treatment episodes. Rheumatologic comorbidities were the most frequent indication. The most common IMD classes were TNF inhibitors, antimetabolites, and checkpoint inhibitors. Ninety percent of treatment episodes involved concomitant ART. Median pretreatment CD4 T-cell count was 609 cells/µl (IQR 375--861). Among 51 treatment episodes on ART with undetectable pretreatment plasma HIV RNA, HIV became detectable within 1 year in 21 of 51 cases (41.2%); there were no instances of virologic failure. Compared with other agents, treatment episodes involving checkpoint inhibitors were more likely to involve a blip (77.8 vs. 33.3%, P = 0.015). Thirteen treatment episodes (11.8%) were associated with concomitant infection; none was attributed to IMDs by the treating clinician. CONCLUSION: PLWH treated with IMDs should be monitored carefully for virologic blips and incident infections. Checkpoint inhibitors may be associated with a higher rate of viral blips, although the clinical significance is unclear.

Lack of association of Aspergillus colonization with the development of bronchiolitis obliterans syndrome in lung transplant recipients: An international cohort study.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is a major limitation in the long-term survival of lung transplant recipients (LTRs). However, the risk factors in the development of BOS remain undetermined. We conducted an international cohort study of LTRs to assess whether Aspergillus colonization with large or small conidia is a risk factor for the development of BOS. METHODS: Consecutive LTRs from January 2005 to December 2008 were evaluated. Rates of BOS and associated risk factors were recorded at 4 years. International Society of Heart and Lung Transplantation criteria were used to define fungal and other infections. A Cox proportional-hazards-model was constructed to assess the association between Aspergillus colonization and the development of BOS controlling for confounders. RESULTS: A total of 747 LTRs were included. The cumulative incidence of BOS at 4 years after transplant was 33% (250 of 747). Additionally, 22% of LTRs experienced Aspergillus colonization after transplantation. Aspergillus colonization with either large (hazard ratio [HR] = 0.6, 95% confidence interval [CI] = 0.3-1.2, p = 0.12) or small conidia (HR = 0.9, 95% CI = 0.6-1.4, p = 0.74) was not associated with the development of BOS. Factors associated with increased risk of development of BOS were the male gender (HR = 1.4, 95% CI = 1.1-1.8, p = 0.02) and episodes of acute rejection (1-2 episodes, HR = 1.5, 95% CI = 1.1-2.1, p = 0.014; 3-4 episodes, HR = 1.6, 95% CI = 1.0-2.6, p = 0.036; >4 episodes, HR = 2.2, 95% CI = 1.1-4.3, p = 0.02), whereas tacrolimus use was associated with reduced risk of BOS (HR = 0.6, 95% CI = 0.5-0.9, p = 0.007). CONCLUSIONS: We conclude from this large multicenter cohort of lung transplant patients, that Aspergillus colonization with large or small conidia did not show an association with the development of BOS.

Human papillomavirus infection in solid organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These guidelines from the American Society of Transplantation Infectious Diseases Community of Practice update the epidemiology and management of human papillomavirus (HPV) infections in organ transplant recipients. HPV is one of the most common sexually transmitted infections and is associated with cancers of the anogenital region. Increasing evidence suggests an association with head and neck cancers as well. Solid organ transplant recipients have a higher risk of HPV infection than the general population. Infection manifests as premalignant lesions, warts, or cancer of the cervix, penis, vulva, scrotum, and anal canal. Most are asymptomatic initially, so diagnosis can be difficult without screening. A vaccine is available though not effective in preventing all cancer-causing strains. Organ transplant recipients should be screened for HPV-associated cancers and appropriate therapy initiated in a timely manner. Further studies are warranted to delineate the most effective screening methods and therapeutic modalities, including whether changes in immunosuppression are effective in attenuating disease.

Clinical risk factors for invasive aspergillosis in lung transplant recipients: Results of an international cohort study.

BACKGROUND: Invasive aspergillosis (IA) is a frequent complication in lung transplant recipients (LTRs). Clinical risk factors for IA have not been fully characterized, especially in the era of extensive anti-fungal prophylaxis. The primary objective of this study was to evaluate the clinical risk factors associated with IA in LTRs. The secondary objective was to assess the mortality in LTRs who had at least 1 episode of IA compared with LTRs who never had experienced IA. METHODS: We conducted an international, multicenter, retrospective cohort study of 900 consecutive adults who received lung transplants between 2005 and 2008 with 4years of follow-up. Risk factors associated with IA were identified using univariate and multiple regression Cox proportional hazards models. RESULTS: Anti-fungal prophylaxis was administered to 61.7% (555 of 900) of patients, and 79 patients developed 115 episodes of IA. The rate to development of the first episode was 29.6 per 1,000 person-years. Aspergillus fumigatus was the most common species isolated (63% [72 of 115 episodes]). Through multivariate analysis, significant risk factors identified for IA development were single lung transplant (hazard ratio, 1.84; 95% confidence interval, 1.09-3.10; p = 0.02,) and colonization with Aspergillus at 1 year post-transplantation (hazard ratio, 2.11; 95% confidence interval, 1.28-3.49; p = 0.003,). Cystic fibrosis, pre-transplant colonization with Aspergillus spp, and use of anti-fungal prophylaxis were not significantly associated with the development of IA. Time-dependent analysis showed IA was associated with higher mortality rates. CONCLUSION: Incidence of IA remains high in LTRs. Single-lung transplant and airway colonization with Aspergillus spp. within 1 year post-transplant were significantly associated with IA.

Organ donor screening practices for Strongyloides stercoralis infection among US organ procurement organizations.

BACKGROUND: Targeted donor screening for strongyloidiasis performed at the time of organ procurement can prevent this life-threatening donor-derived infection. METHOD: The Association of Organ Procurement Organizations surveyed members to determine the number of US organ procurement organizations (OPOs) performing donor screening for Strongyloides infection and their screening practices. RESULTS: All 58 OPOs responded to the survey. Only 6 (10%) currently screen donors for strongyloidiasis; most OPOs started 6-36 months before the survey and one started 6 years prior. All used risk-based criteria to determine which donors to screen, though the criteria varied among OPOs. A median of 56 donors have been screened at each OPO since initiating their screening programs, with a median of 2 infected donors (range 0-13) identified. Overall, 53 organs have been transplanted from 22 infected donors, including hearts, lungs, kidneys, and livers. Of 52 OPOs not currently screening, 20 had considered screening and one plans to start screening in the near future. Of those considering risk-based screening, most had not decided on the criteria. Uncertainty about the benefits of and guidelines for screening and misconceptions about the interpretation of test results were concerns shared by non-screening OPOs. CONCLUSION: Continued education and advocacy on the importance of targeted donor screening are needed.

An Interprofessional Curriculum on Antimicrobial Stewardship Improves Knowledge and Attitudes Toward Appropriate Antimicrobial Use and Collaboration.

BACKGROUND: Inappropriate antimicrobial use can threaten patient safety and is the focus of collaborative physician and pharmacist antimicrobial stewardship teams. However, antimicrobial stewardship is not comprehensively taught in medical or pharmacy school curricula. Addressing this deficiency can teach an important concept as well as model interprofessional healthcare. METHODS: We created an antimicrobial stewardship curriculum consisting of an online learning module and workshop session that combined medical and pharmacy students, with faculty from both professions. Learners worked through interactive, branched-logic clinical cases relating to appropriate antimicrobial use. We surveyed participants before and after the curriculum using validated questions to assess knowledge and attitudes regarding antimicrobial stewardship and interprofessional collaboration. Results were analyzed using paired χ2 and t tests and mixed-effects logistic regression. RESULTS: Analysis was performed with the 745 students (425 medical students, 320 pharmacy students) who completed both pre- and postcurriculum surveys over 3 years. After completing the curriculum, significantly more students perceived that they were able to describe the role of each profession in appropriate antimicrobial use (34% vs 82%, P < .001), communicate in a manner that engaged the interprofessional team (75% vs 94%, P < .001), and describe collaborative approaches to appropriate antimicrobial use (49% vs 92%, P < .001). Student favorability ratings were high for the online learning module (85%) and small group workshop (93%). CONCLUSIONS: A curriculum on antimicrobial stewardship consisting of independent learning and an interprofessional workshop significantly increased knowledge and attitudes towards collaborative antimicrobial stewardship among preclinical medical and pharmacy students.

Epstein-Barr Virus Neuroretinitis in a Lung Transplant Patient.

Epstein-Barr virus (EBV)-associated optic neuropathy is rare with few reported cases, mostly involving immunocompetent patients who developed optic nerve involvement after infectious mononucleosis. We describe a unique case of a patient who developed severe bilateral EBV neuroretinitis after solid organ transplant.

Human Papillomavirus in Kidney Transplant Recipients.

Human papillomavirus (HPV) is a common infection in kidney transplant recipients. HPV causes cervical, anal, vulvar, vaginal, penile and head and neck cancers. Kidney transplant recipients have a disproportionate burden of disease given prolonged immunosuppression. Given the long pre-invasive state of precancer lesions such as cervical intraepithelial neoplasia (CIN) and anal intraepithelial neoplasia (AIN) most HPV-cancers are preventable with screening and targeted treatment of disease. Pre-transplant vaccination of age-eligible kidney transplant recipients is otherwise ideal.

Endemic mycoses in immunocompromised hosts.

Endemic mycoses remain a significant cause of morbidity and mortality among immunocompromised patients. As the number of immunosuppressed individuals increases worldwide, the incidence of endemic mycoses is also expected to rise. In immunocompromised patients, endemic mycoses can present in atypical fashion, cause more severe and/or disseminated disease, and result in higher mortality. Despite several noteworthy advances over the past decade, significant challenges remain with regard to the prevention, diagnosis, and therapy of endemic mycoses in immunocompromised hosts. This review highlights important developments related to the epidemiology, diagnosis, treatment, and prevention of commonly encountered endemic mycoses. We also discuss emerging topics, knowledge gaps, and areas of future research.

Use of rifabutin for the treatment of a latent tuberculosis infection in a patient after solid organ transplantation.

Latent tuberculosis infection is an important problem for solid organ transplant recipients because of the frequency of its occurrence and its potential for reactivation. Because of the high mortality rate associated with active tuberculosis infections in transplant recipients, guidelines from the American Thoracic Society recommend treatment for latent tuberculosis in this population. However, the choice of treatments is often difficult because liver transplant recipients may be more sensitive to isoniazid hepatotoxicity, and rifampin has significant drug interactions with the calcineurin inhibitors used for immunosuppression. Two prior case reports described success with the use of rifabutin, a rifampin alternative, as part of a multidrug treatment regimen for active tuberculosis in posttransplant patients; however, there is no prior literature describing any experience with rifabutin for the treatment of latent tuberculosis in the posttransplant setting. We present a summary of tacrolimus drug levels and corresponding dose requirements for a single posttransplant patient during the administration of 3 different latent tuberculosis drug regimens: rifampin alone, rifampin plus ketoconazole, and rifabutin. In this patient's case, rifabutin allowed the maintenance of adequate tacrolimus levels, although an approximate 2.5-fold increase in the dose was required. Rifampin alone was associated with inadequate immunosuppressant levels, and rifampin plus ketoconazole was associated with a problematically prolonged QT interval and concerns about inadequate tuberculosis treatment.

Risk factors for mortality in patients with mucormycosis.

Optimal clinical care and clinical investigation of patients with mucormycosis are limited by absence of controlled trials, and absence of well-defined predictors of mortality or clinical response. The Deferasirox-AmBisome Therapy for mucormycosis (DEFEAT Mucor) study was the first randomized clinical trial conducted on patients with mucormycosis, and demonstrated that adjunctive deferasirox therapy did not improve outcomes of the disease. The current study describes clinical factors from the 20 patients enrolled to identify those associated with 90-day mortality of the 11 (55%) patients who died by day 90. Age, diabetes mellitus, transplant status, or antifungal therapy were not associated with mortality. However, active malignancy or neutropenia at enrollment were associated with increased mortality. Pulmonary infection was linked with lower Kaplan-Meier survival compared to non-pulmonary infection. Higher baseline serum concentrations of iron and ferritin were also associated with mortality. No patient who progressed clinically during the first 14 days of study therapy survived; however, many patients who clinically improved during that time did not survive to 90 days. In contrast, day 30 clinical response was predictive of 90-day survival. These factors may be useful in defining enrollment randomization stratification critieria for future clinical trials, and in supporting clinical care of patients with mucormycosis.