Microscopic Small Airway Abnormalities Identified in Early Idiopathic Pulmonary Fibrosis In Vivo Using Endobronchial Optical Coherence Tomography.

RATIONALE: Idiopathic pulmonary fibrosis (IPF) affects subpleural lung, but is considered to spare small airways. Micro-CT studies demonstrated small airway reduction in end-stage IPF explanted lungs, raising questions about small airway involvement in early-stage disease. Endobronchial optical coherence tomography (EB-OCT) is a volumetric imaging modality that detects microscopic features from subpleural to proximal airways. We use EB-OCT to evaluate small airways in early IPF and control subjects in vivo. METHODS: EB-OCT was performed in 12 IPF and 5 control subjects (matched by age, sex, smoking-history, height, BMI). IPF subjects had early disease with mild restriction (FVC: 83.5% predicted), diagnosed per current guidelines and confirmed by surgical biopsy. EB-OCT volumetric imaging was acquired bronchoscopically in multiple, distinct, bilateral lung locations (total: 97 sites). IPF imaging sites were classified by severity into affected (all criteria for UIP present) and less affected (some but not all criteria for UIP present) sites. Bronchiole count and small airway stereology metrics were measured for each EB-OCT imaging site. RESULTS: Compared to control subjects (mean: 11.2 bronchioles/cm3; SD: 6.2), there was significant bronchiole reduction in IPF subjects (42% loss; mean: 6.5/cm3; SD: 3.4; p=0.0039), including in IPF affected (48% loss; mean: 5.8/cm3; SD: 2.8; p<0.00001) and IPF less affected (33% loss; mean: 7.5/cm3; SD: 4.1; p=0.024) sites. Stereology metrics showed IPF affected small airways were significantly larger and more distorted/irregular than in IPF less affected sites and control subjects. IPF less affected and control airways were statistically indistinguishable for all stereology parameters (p=0.36-1.0). CONCLUSION: EB-OCT demonstrated marked bronchiolar loss in early IPF (between 30 and 50%), even in areas minimally affected by disease, compared to matched controls. These findings support small airway disease as a feature of early IPF, providing novel insight into pathogenesis and potential therapeutic targets.

Therapeutic Targeting of DNA Repair Pathways in Pediatric Extracranial Solid Tumors: Current State and Implications for Immunotherapy.

DNA damage is fundamental to tumorigenesis, and the inability to repair DNA damage is a hallmark of many human cancers. DNA is repaired via the DNA damage repair (DDR) apparatus, which includes five major pathways. DDR deficiencies in cancers give rise to potential therapeutic targets, as cancers harboring DDR deficiencies become increasingly dependent on alternative DDR pathways for survival. In this review, we summarize the DDR apparatus, and examine the current state of research efforts focused on identifying vulnerabilities in DDR pathways that can be therapeutically exploited in pediatric extracranial solid tumors. We assess the potential for synergistic combinations of different DDR inhibitors as well as combinations of DDR inhibitors with chemotherapy. Lastly, we discuss the immunomodulatory implications of targeting DDR pathways and the potential for using DDR inhibitors to enhance tumor immunogenicity, with the goal of improving the response to immune checkpoint blockade in pediatric solid tumors. We review the ongoing and future research into DDR in pediatric tumors and the subsequent pediatric clinical trials that will be critical to further elucidate the efficacy of the approaches targeting DDR.

Understanding Barriers and Facilitators of Primary Care Use Among Assertive Community Treatment Teams Via Qualitative Analysis of Clients and Clinicians.

Individuals with severe mental illness and substance use disorders face complex barriers to achieving physical health. This study aims to explore the barriers and facilitators of primary care access among an Assertive Community Treatment (ACT) team. Semi-structured qualitative interviews were conducted with 14 clients and 7 clinicians from an ACT team at a community mental health center in Connecticut. Data analysis followed a grounded theory approach, with codes and themes emerging iteratively during the interview process. The study identified multifaceted barriers to accessing primary care, including economic challenges, homelessness, and the prioritization of mental health and substance use symptoms over healthcare. The conceptual framework consists of nine dominant themes: clients' attitudes, knowledge, mental health, and motivations ("Client-Level Barriers and Facilitators"); ACT team-directed care coordination and relationship-building as well as primary care provider communication ("Provider-Level Barriers and Facilitators"); and clients' experiences with medical care and socioeconomic status ("Systemic-Level Barriers and Facilitators"). This research provides valuable insights into the various barriers faced by ACT clients in accessing primary care. Improving primary care access for individuals with severe mental illness and substance use disorders is crucial for reducing health disparities in this vulnerable population.

Observational pilot study of multi-wavelength wearable light dosimetry for erythropoietic protoporphyria.

BACKGROUND: Erythropoietic protoporphyria (EPP) causes painful light sensitivity, limiting quality of life. Our objective was to develop and validate a wearable light exposure device and correlate measurements with light sensitivity in EPP to predict and prevent symptoms. METHODS: A wearable light dosimeter was developed to capture light doses of UVA, blue, and red wavelengths. A prospective observational pilot study was performed in which five EPP patients wore two light dosimeters for 3 weeks, one as a watch, and one as a shirt clip. RESULTS: Standard deviation (SD) increases from the mean in the daily blue light dose increased the odds ratio (OR) for symptom risk more than the self-reported outdoor time (OR 2.76 vs. 2.38) or other wavelengths, and a one SD increase from the mean in the daily blue light wristband device dose increased the OR for symptom risk more than the daily blue light shirt clip (OR 2.45 vs. 1.62). The area under the receiver operator curve for the blue light wristband dose was 0.78, suggesting 78% predictive accuracy. CONCLUSION: These data demonstrate that wearable blue light dosimetry worn as a wristband is a promising method for measuring light exposure and predicting and preventing symptoms in EPP.

Venovenous Extracorporeal Membrane Oxygenation Candidacy Decision-Making: Lessons and Hypotheses From a Single-Center Observational Analysis.

BACKGROUND: Use of venovenous extracorporeal membrane oxygenation (ECMO) is increasing, but candidacy selection processes are variable and subject to bias. RESEARCH QUESTION: What are the reasons behind venovenous ECMO candidacy decisions, and are decisions made consistently across patients? STUDY DESIGN AND METHODS: Prospective observational study of all patients, admitted or outside hospital referrals, considered for venovenous ECMO at a tertiary referral center. Relevant clinical data and reasons for candidacy determination were cross-referenced with other noncandidates and candidates and were assessed qualitatively. RESULTS: Eighty-one consultations resulted in 44 noncandidates (54%), 29 candidates (36%; nine of whom subsequently underwent cannulation), and eight deferred decisions (10%). Fifteen unique contraindications were identified, variably present across all patients. Five contraindications were invoked as the sole reason to deny ECMO to a patient. In patients with three or more contraindications, additional contraindications were cited even if the severity was relatively minor. All but four contraindications invoked to deny ECMO to a patient were nonprohibitive for at least one other candidate. Contraindications documented in noncandidates were present but not mentioned in 21 other noncandidates (47%). Twenty-six candidates (90%) had at least one contraindication that was prohibitive in a noncandidate, including a contraindication that was the sole reason to deny ECMO. Contraindications were proposed as informing three prognostic domains, through which patterns of inconsistency could be understood better: (1) irreversible underlying pulmonary process, (2) unsurvivable critical illness, and (3) clinical condition too compromised for meaningful recovery. INTERPRETATION: ECMO candidacy decisions are inconsistent. We identified four patterns of inconsistency in our center and propose a three-domain model for understanding and categorizing contraindications, yielding five lessons that may improve candidacy decision processes until further research can guide practice more definitively.

Hormonal contraception and cognition: Considering the influence of endogenous ovarian hormones and genes for clinical translation.

Despite the well-known influence of ovarian hormones on the brain and widespread use of hormonal contraception (HC) since the 1960s, our knowledge of HC's cognitive effects remains limited. To date, the cognitive findings have been inconsistent. In order to establish what might make HC studies more consistent, we surveyed the literature on HCs and cognition to determine whether studies considered HC formulation, phase, pharmacokinetics, duration, and gene interactions, and assessed whether oversight of these factors might contribute to variable findings. We found that synthetic HC hormones exert dose-dependent effects, the day of oral contraceptive (Pill) ingestion is critical for understanding cognitive changes, and gene-cognition relationships differ in women taking the Pill likely due to suppressed endogenous hormones. When these factors were overlooked, results were not consistent. We close with recommendations for research more likely to yield consistent findings and be therefore, translatable.

Effect of remdesivir on adverse kidney outcomes in hospitalized patients with COVID-19 and impaired kidney function.

BACKGROUND: Chronic kidney disease (CKD) is an important risk factor for mortality from COVID-19. Remdesivir has been shown to shorten time to recovery in patients with severe COVID-19. However, exclusion of patients with severe kidney function impairment in clinical trials has led to concerns about kidney safety of remdesivir in patients with pre-existing kidney disease. METHODS: Retrospective propensity score matched cohort study of hospitalized patients with COVID-19 admitted with estimated glomerular filtration rate (eGFR) between 15 - 60 mL/min/1.73m2. Remdesivir-treated patients were 1:1 matched to historical comparators admitted during the first wave of COVID-19 (between March-April 2020) prior to emergency use authorization of remdesivir using propensity scores accounting for factors predicting treatment assignment. Dependent outcomes included in-hospital peak creatinine, incidence of doubling of creatine, rate of kidney replacement therapy initiation and eGFR among surviving patients at day 90. RESULTS: 175 remdesivir-treated patients were 1:1 matched to untreated historical comparators. Mean age was 74.1 (SD 12.8), 56.9% were male, 59% patients were white, and the majority (83.1%) had at least one co-morbidity. There were no statistically significant differences in peak creatinine during hospitalization (2.3mg/dL vs. 2.5 mg/dL, P = 0.34), incidence of doubling of creatinine (10.3% vs. 13.1%, P = 0.48), and rate of kidney replacement therapy initiation (4.6% vs. 6.3%, P = 0.49) in remdesivir-treated patients versus matched untreated historical comparators, respectively. Among surviving patients, there was no difference of the average eGFR at day 90 (54.7 ± 20.0 mL/min/1.73m2 for remdesivir-treated patients vs. 51.7 ± 19.5 mL/min/1.73m2 for untreated comparators, P = 0.41). CONCLUSIONS: Remdesivir use in patients with impaired kidney function (eGFR between 15 - 60 mL/min/1.73m2) who present to the hospital with COVID-19 is not associated with increased risk of adverse kidney outcomes.

Safety of Immune Checkpoint Inhibitors in Patients With Advanced Chronic Kidney Disease: A Retrospective Cohort Study.

BACKGROUND: Clinical trials of immune checkpoint inhibitors (ICIs) often do not include patients with advanced chronic kidney disease (CKD). We aimed to determine the safety of ICIs in patients with cancer and advanced CKD (stages 4-5 CKD, estimated glomerular filtration rate [eGFR] <30 mL/minute/1.73 m2). PATIENTS AND METHODS: Patients with advanced CKD from the Mass General Brigham network who received ICIs (n = 91) were compared against those receiving nephrotoxic (n = 113) and non-nephrotoxic (n = 130) antineoplastic therapies, respectively. Rates of new-onset kidney failure (end-stage kidney disease or sustained eGFR ≤10 mL/minute/1.73 m2) and AKI were compared. Among ICI-treated patients, we modeled Fine-Gray subdistribution hazards to compare immune-related adverse event (irAE) risk and used Kaplan-Meier analysis to compare overall survival in patients with advanced CKD to those with eGFR ≥30 mL/minute/1.73 m2. RESULTS: Rates of new-onset kidney failure were similar at 1 year following initiation of ICIs (10.0%), nephrotoxic (6.2%), and non-nephrotoxic antineoplastic therapies (9.3%) (P = .28). AKI rates were also similar: 17.5%, 17.6%, and 20% of patients in each cohort, respectively (P = .87). Advanced CKD did not increase the risk of developing irAEs (adjusted hazard ratio [HR] 1.28, 95% CI, 0.91-1.81). However, patients with advanced CKD who received ICIs had a decreased overall survival compared with patients with eGFR ≥30 mL/minute/1.73 m2 (HR 1.30 for death, 95% CI, 1.02-1.66, P = .03). CONCLUSION: ICIs are not associated with increased risk of AKI or new-onset kidney failure compared with other antineoplastic therapies in patients with advanced CKD. Advanced CKD did not increase the risk of extra-renal irAEs, although these patients suffered from lower overall survival.

Protein Carbamylation and the Risk of ESKD in Patients with CKD.

SIGNIFICANCE STATEMENT: Protein carbamylation, a nonenzymatic post-translational protein modification partially driven by elevated blood urea levels, associates with mortality and adverse outcomes in patients with ESKD on dialysis. However, little is known about carbamylation's relationship to clinical outcomes in the much larger population of patients with earlier stages of CKD. In this prospective observational cohort study of 3111 individuals with CKD stages 2-4, higher levels of carbamylated albumin (a marker of protein carbamylation burden) were associated with a greater risk of developing ESKD and other significant adverse clinical outcomes. These findings indicate that protein carbamylation is an independent risk factor for CKD progression. They suggest that further study of therapeutic interventions to prevent or reduce carbamylation is warranted. BACKGROUND: Protein carbamylation, a post-translational protein modification partially driven by elevated blood urea levels, associates with adverse outcomes in ESKD. However, little is known about protein carbamylation's relationship to clinical outcomes in the much larger population of patients with earlier stages of CKD. METHODS: To test associations between protein carbamylation and the primary outcome of progression to ESKD, we measured baseline serum carbamylated albumin (C-Alb) in 3111 patients with CKD stages 2-4 enrolled in the prospective observational Chronic Renal Insufficiency Cohort study. RESULTS: The mean age of study participants was 59 years (SD 10.8); 1358 (43.7%) were female, and 1334 (42.9%) were White. The mean eGFR at the time of C-Alb assessment was 41.8 (16.4) ml/minute per 1.73 m 2 , and the median C-Alb value was 7.8 mmol/mol (interquartile range, 5.8-10.7). During an average of 7.9 (4.1) years of follow-up, 981 (31.5%) individuals developed ESKD. In multivariable adjusted Cox models, higher C-Alb (continuous or quartiles) independently associated with an increased risk of ESKD. For example, compared with quartile 1 (C-Alb ≤5.80 mmol/mol), those in quartile 4 (C-Alb >10.71 mmol/mol) had a greater risk for ESKD (adjusted hazard ratio, 2.29; 95% confidence interval, 1.75 to 2.99), and the ESKD incidence rate per 1000 patient-years increased from 15.7 to 88.5 from quartile 1 to quartile 4. The results remained significant across numerous subgroup analyses, when treating death as a competing event, and using different assessments of eGFR. CONCLUSIONS: Having a higher level of protein carbamylation as measured by circulating C-Alb is an independent risk factor for ESKD in individuals with CKD stages 2-4. PODCAST: This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2023_04_24_JSN_URE_EP22_042423.mp3.

Severe Hyponatremia Correction, Mortality, and Central Pontine Myelinolysis.

BACKGROUND: In clinical practice, sodium correction rates are frequently limited in patients with severe hyponatremia to prevent neurologic complications. The implications of correction rates on overall mortality and length of hospital stay are unclear. METHODS: In this multicenter observational study, we evaluated the association of sodium correction rates with mortality, length of stay, and central pontine myelinolysis (CPM) in patients hospitalized with severe hyponatremia (admission serum sodium level less than 120 mEq/l). RESULTS: The cohort included 3274 patients. A correction rate of less than 6 mEq/l/24 hours was observed in 38%, 6 to 10 mEq/l/24 hours was observed in 29%, and greater than 10 mEq/l/24 hours was observed in 33%. Compared with 6 to 10 mEq/l/24 hours, a correction rate of less than 6 mEq/l/24 hours exhibited higher in-hospital mortality in multivariable-adjusted and propensity score­weighted analyses. Compared with 6 to 10 mEq/l/24 hours, a correction rate of greater than 10 mEq/l/24 hours was associated with lower in-hospital mortality and shorter length of stay in multivariable analyses. Seven patients with CPM were identified, with five of seven developing CPM despite a sodium correction rate of less than or equal to 8 mEq/l/24 hours. Six of seven patients who developed CPM had alcohol use disorder, malnutrition, hypokalemia, or hypophosphatemia. CONCLUSIONS: Limiting the sodium correction rate was associated with higher mortality and longer length of stay. Whether the sodium correction rate influences neurologic complications needs further evaluation.

A Propensity Score-Matched Observational Study of Remdesivir in Patients with COVID-19 and Severe Kidney Disease.

Background: Remdesivir is not currently approved for patients with eGFR <30 ml/min per 1.73 m2. We aimed to determine the safety of remdesivir in patients with kidney failure. Methods: This study was a retrospective cohort study of patients with COVID-19 hospitalized between May 2020 and January 2021 with eGFR <30 ml/min per 1.73 m2 who received remdesivir and historical controls with COVID-19 hospitalized between March 1, 2020 and April 30, 2020 prior to the emergency use authorization of remdesivir within a large health care system. Patients were 1:1 matched by propensity scores accounting for factors associated with treatment assignment. Adverse events and hospital outcomes were recorded by manual chart review. Results: The overall cohort included 34 hospitalized patients who initiated remdesivir within 72 hours of hospital admission with eGFR<30 ml/min per 1.73 m2 and 217 COVID-19 controls with eGFR <30 ml/min per 1.73 m2. The propensity score-matched cohort included 31 remdesivir-treated patients and 31 nonremdesivir-treated controls. The mean age was 74.0 (SD=13.8) years, 57% were women, and 68% were white participants. A total of 26% had ESKD. Among patients who were not on dialysis prior to initiating remdesivir, one developed worsening kidney function (defined as ≥50% increase in creatinine or initiation of KRT) compared with three in the historical control group. There was no increased risk of cardiac arrythmia, cardiac arrest, altered mental status, or clinically significant anemia or liver function test abnormalities. There was a significantly increased risk of hyperglycemia, which may be partly explained by the increased use of dexamethasone in the remdesivir-treated population. Conclusions: In this propensity score-matched study, remdesivir was well tolerated in patients with eGFR <30 ml/min per 1.73 m2.

Trajectories of Uremic Symptom Severity and Kidney Function in Patients with Chronic Kidney Disease.

BACKGROUND AND OBJECTIVES: Uremic symptoms, including fatigue, anorexia, pruritus, nausea, paresthesia, and pain, are attributed to the accumulation of organic waste products normally cleared by the kidneys, but whether kidney function is the primary driver of changes in symptom severity over time is not known. The goal of our study was to evaluate the association between eGFR and uremic symptom severity score in patients with CKD. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: We identified 3685 participants with CKD not on dialysis in the prospective, observational Chronic Renal Insufficiency Cohort (CRIC) Study with baseline assessment of eGFR and uremic symptom severity. Symptoms were assessed by separate questions on the Kidney Disease Quality of Life-36 instrument (zero- to 100-point scale). The longitudinal association between eGFR and uremic symptom severity score was examined with multivariable adjusted linear mixed-effects models with random intercepts and random slopes. RESULTS: The mean±SD eGFR at baseline was 44±15 ml/min per 1.73 m2, and participants had a median of six (interquartile range 3-11) simultaneous assessments of eGFR and uremic symptoms over the duration of follow-up. The most prevalent symptoms at baseline were pain (57%), fatigue (52%), paresthesia (45%), and pruritus (42%). In adjusted models, a decrease in eGFR of 5 ml/min per 1.73 m2 was associated with a worsening of the symptom severity score by two points or less for each uremic symptom (P<0.01; zero- to 100-point scale). The association between eGFR and uremic symptom severity score was nonlinear. When starting from a lower initial eGFR, a 5 ml/min per 1.73 m2 decrease in eGFR was associated with a greater magnitude of uremic symptom worsening. CONCLUSIONS: The prevalence of uremic symptoms in CKD is high, with significant variability in patient symptom change over time. Declines in eGFR were associated with worsening of uremic symptom severity, but the magnitude of these changes is small and of uncertain clinical significance.