Chronic Kidney Disease Is Characterized by Expansion of a Distinct Proinflammatory Intermediate Monocyte Subtype and by Increased Monocyte Adhesion to Endothelial Cells.

SIGNIFICANCE STATEMENT: CKD is accompanied by abnormal inflammation, which contributes to progressive loss of functional renal tissue and accelerated cardiovascular disease. Although studies have documented that dysregulation of monocyte maturation and function is associated with CKD and its complications, it is not well characterized. This study reveals that a distinctive human monocyte subtype with high propensity for releasing proinflammatory mediators and activating endothelial cells is increased in adults with CKD compared with adults with high cardiovascular risk and normal kidney function. It also demonstrates that human monocyte adhesion to endothelial layers and responses to specific inflammatory migration signals are enhanced in CKD. These findings offer insights into the mechanisms of CKD-associated intravascular and localized inflammation and may suggest potential targets for therapeutic interventions. BACKGROUND: Cardiovascular disease (CVD) in patients with CKD is associated with increased circulating intermediate monocytes (IMs). Dysregulation of monocyte maturation and function is associated with CKD and its complications, but it is incompletely characterized. METHODS: To explore monocyte repertoire abnormalities in CKD, we studied properties of monocyte subpopulations, including IM subpopulations distinguished by HLA-DR expression level, in individuals with or without CKD. Using flow cytometry, we profiled monocyte populations in blood samples from adults with CKD, healthy volunteers (HVs), and patient controls (PCs) with high CVD risk. Monocyte subpopulations were also derived from single-cell RNA-sequencing profiles of paired blood and biopsy samples from kidney transplant recipients. We quantified intracellular cytokine production, migration, and endothelial adhesion in ex vivo assays of PBMCs. RESULTS: Of four predefined blood monocyte subpopulations, only HLA-DR hi IMs were increased in individuals with CKD compared with HVs and PCs. In HVs and patients with CKD, LPS-stimulated HLA-DR hi IMs isolated from blood produced higher amounts of TNF and IL-1 ß than other monocyte populations. Single-cell analysis revealed four monocyte clusters common to blood and kidneys, including an HLA-DR hi IM-like cluster that was enriched in kidneys versus blood. Migration toward CCL5 and CX3CL1 and adhesion to primary endothelial cell layers were increased in monocyte subpopulations in individuals with CKD compared with HVs. Monocyte adhesion to endothelial cells was partly dependent on CX3CR1/CX3CL1 interaction. CONCLUSIONS: CKD is associated with an increased number of a distinctive proinflammatory IM subpopulation and abnormalities of monocyte migration and endothelial adhesion. Dysregulated monocyte maturation and function may represent targetable factors contributing to accelerated CVD in CKD.

Image-based computer modeling assessment of microwave ablation for treatment of adrenal tumors.

PURPOSE: To assess the feasibility of delivering microwave ablation for targeted treatment of aldosterone producing adenomas using image-based computational models. METHODS: We curated an anonymized dataset of diagnostic 11C-metomidate PET/CT images of 14 patients with aldosterone producing adenomas (APA). A semi-automated approach was developed to segment the APA, adrenal gland, and adjacent organs within 2 cm of the APA boundary. The segmented volumes were used to implement patient-specific 3D electromagnetic-bioheat transfer models of microwave ablation with a 2.45 GHz directional microwave ablation applicator. Ablation profiles were quantitatively assessed based on the extent of the APA target encompassed by an ablative thermal dose, while limiting thermal damage to the adjacent normal adrenal tissue and sensitive critical structures. RESULTS: Across the 14 patients, adrenal tumor volumes ranged between 393 mm3 and 2,395 mm3. On average, 70% of the adrenal tumor volumes received an ablative thermal dose of 240CEM43, while limiting thermal damage to non-target structures, and thermally sparing 83.5-96.4% of normal adrenal gland. Average ablation duration was 293 s (range: 60-600 s). Simulations indicated coverage of the APA with an ablative dose was limited when the axis of the ablation applicator was not well aligned with the major axis of the targeted APA. CONCLUSIONS: Image-based computational models demonstrate the potential for delivering microwave ablation to APA targets within the adrenal gland, while limiting thermal damage to surrounding non-target structures.

System for delivering microwave ablation to subcutaneous tumors in small-animals under high-field MRI thermometry guidance.

PURPOSE: Bio-effects following thermal treatments are a function of the achieved temperature profile in tissue, which can be estimated across tumor volumes with real-time MRI thermometry (MRIT). Here, we report on expansion of a previously developed small-animal microwave hyperthermia system integrated with MRIT for delivering thermal ablation to subcutaneously implanted tumors in mice. METHODS: Computational models were employed to assess suitability of the 2.45 GHz microwave applicators for delivering ablation to subcutaneous tumor targets in mice. Phantoms and ex-vivo tissues were heated to temperatures in the range 47-67 °C with custom-made microwave applicators for validating MRIT with the proton resonance frequency shift method against fiberoptic thermometry. HAC15 tumors implanted in nude mice (n = 6) were ablated in vivo and monitored with MRIT in multiple planes. One day post ablation, animals were euthanized, and excised tumors were processed for viability assessment. RESULTS: Average absolute error between temperatures from fiberoptic sensors and MRIT was 0.6 °C across all ex-vivo ablations. During in-vivo experiments, tumors with volumes ranging between 5.4-35.9 mm3 (mean 14.2 mm3) were ablated (duration: 103-150 s) to achieve 55 °C at the tumor boundary. Thermal doses ≥240 CEM43 were achieved across 90.7-98.0% of tumor volumes for four cases. Ablations were incomplete for remaining cases, attributed to motion-affected thermometry. Thermal dose-based ablative tumor coverage agreed with viability assessment of excised tumors. CONCLUSIONS: We have developed a system for delivering microwave ablation to subcutaneous tumors in small animals under MRIT guidance and demonstrated its performance in-vivo.

Cardiometabolic Disease Burden and Steroid Excretion in Benign Adrenal Tumors : A Cross-Sectional Multicenter Study.

BACKGROUND: Benign adrenal tumors are commonly discovered on cross-sectional imaging. Mild autonomous cortisol secretion (MACS) is regularly diagnosed, but its effect on cardiometabolic disease in affected persons is ill defined. OBJECTIVE: To determine cardiometabolic disease burden and steroid excretion in persons with benign adrenal tumors with and without MACS. DESIGN: Cross-sectional study. SETTING: 14 endocrine secondary and tertiary care centers (recruitment from 2011 to 2016). PARTICIPANTS: 1305 prospectively recruited persons with benign adrenal tumors. MEASUREMENTS: Cortisol excess was defined by clinical assessment and the 1-mg overnight dexamethasone-suppression test (serum cortisol: <50 nmol/L, nonfunctioning adrenal tumor [NFAT]; 50 to 138 nmol/L, possible MACS [MACS-1]; >138 nmol/L and absence of typical clinical Cushing syndrome [CS] features, definitive MACS [MACS-2]). Net steroid production was assessed by multisteroid profiling of 24-hour urine by tandem mass spectrometry. RESULTS: Of the 1305 participants, 49.7% had NFAT (n = 649; 64.1% women), 34.6% had MACS-1 (n = 451; 67.2% women), 10.7% had MACS-2 (n = 140; 73.6% women), and 5.0% had CS (n = 65; 86.2% women). Prevalence and severity of hypertension were higher in MACS-2 and CS than NFAT (adjusted prevalence ratios [aPRs] for hypertension: MACS-2, 1.15 [95% CI, 1.04 to 1.27], and CS, 1.37 [CI, 1.16 to 1.62]; aPRs for use of ≥3 antihypertensives: MACS-2, 1.31 [CI, 1.02 to 1.68], and CS, 2.22 [CI, 1.62 to 3.05]). Type 2 diabetes was more prevalent in CS than NFAT (aPR, 1.62 [CI, 1.08 to 2.42]) and more likely to require insulin therapy for MACS-2 (aPR, 1.89 [CI, 1.01 to 3.52]) and CS (aPR, 3.06 [CI, 1.60 to 5.85]). Urinary multisteroid profiling revealed an increase in glucocorticoid excretion from NFAT over MACS-1 and MACS-2 to CS, whereas androgen excretion decreased. LIMITATIONS: Cross-sectional design; possible selection bias. CONCLUSION: A cardiometabolic risk condition, MACS predominantly affects women and warrants regular assessment for hypertension and type 2 diabetes. PRIMARY FUNDING SOURCE: Diabetes UK, the European Commission, U.K. Medical Research Council, the U.K. Academy of Medical Sciences, the Wellcome Trust, the U.K. National Institute for Health Research, the U.S. National Institutes of Health, the Claire Khan Trust Fund at University Hospitals Birmingham Charities, and the Mayo Clinic Foundation for Medical Education and Research.

Urine steroid metabolomics for the differential diagnosis of adrenal incidentalomas in the EURINE-ACT study: a prospective test validation study.

BACKGROUND: Cross-sectional imaging regularly results in incidental discovery of adrenal tumours, requiring exclusion of adrenocortical carcinoma (ACC). However, differentiation is hampered by poor specificity of imaging characteristics. We aimed to validate a urine steroid metabolomics approach, using steroid profiling as the diagnostic basis for ACC. METHODS: We did a prospective multicentre study in adult participants (age ≥18 years) with newly diagnosed adrenal masses. We assessed the accuracy of diagnostic imaging strategies based on maximum tumour diameter (≥4 cm vs <4 cm), imaging characteristics (positive vs negative), and urine steroid metabolomics (low, medium, or high risk of ACC), separately and in combination, using a reference standard of histopathology and follow-up investigations. With respect to imaging characteristics, we also assessed the diagnostic utility of increasing the unenhanced CT tumour attenuation threshold from the recommended 10 Hounsfield units (HU) to 20 HU. FINDINGS: Of 2169 participants recruited between Jan 17, 2011, and July 15, 2016, we included 2017 from 14 specialist centres in 11 countries in the final analysis. 98 (4·9%) had histopathologically or clinically and biochemically confirmed ACC. Tumours with diameters of 4 cm or larger were identified in 488 participants (24·2%), including 96 of the 98 with ACC (positive predictive value [PPV] 19·7%, 95% CI 16·2-23·5). For imaging characteristics, increasing the unenhanced CT tumour attenuation threshold to 20 HU from the recommended 10 HU increased specificity for ACC (80·0% [95% CI 77·9-82·0] vs 64·0% [61·4-66.4]) while maintaining sensitivity (99·0% [94·4-100·0] vs 100·0% [96·3-100·0]; PPV 19·7%, 16·3-23·5). A urine steroid metabolomics result indicating high risk of ACC had a PPV of 34·6% (95% CI 28·6-41·0). When the three tests were combined, in the order of tumour diameter, positive imaging characteristics, and urine steroid metabolomics, 106 (5·3%) participants had the result maximum tumour diameter of 4 cm or larger, positive imaging characteristics (with the 20 HU cutoff), and urine steroid metabolomics indicating high risk of ACC, for which the PPV was 76·4% (95% CI 67·2-84·1). 70 (3·5%) were classified as being at moderate risk of ACC and 1841 (91·3%) at low risk (negative predictive value 99·7%, 99·4-100·0). INTERPRETATION: An unenhanced CT tumour attenuation cutoff of 20 HU should replace that of 10 HU for exclusion of ACC. A triple test strategy of tumour diameter, imaging characteristics, and urine steroid metabolomics improves detection of ACC, which could shorten time to surgery for patients with ACC and help to avoid unnecessary surgery in patients with benign tumours. FUNDING: European Commission, UK Medical Research Council, Wellcome Trust, and UK National Institute for Health Research, US National Institutes of Health, the Claire Khan Trust Fund at University Hospitals Birmingham Charities, and the Mayo Clinic Foundation for Medical Education and Research.

Urine Steroid Metabolomics as a Novel Tool for Detection of Recurrent Adrenocortical Carcinoma.

CONTEXT: Urine steroid metabolomics, combining mass spectrometry-based steroid profiling and machine learning, has been described as a novel diagnostic tool for detection of adrenocortical carcinoma (ACC). OBJECTIVE, DESIGN, SETTING: This proof-of-concept study evaluated the performance of urine steroid metabolomics as a tool for postoperative recurrence detection after microscopically complete (R0) resection of ACC. PATIENTS AND METHODS: 135 patients from 14 clinical centers provided postoperative urine samples, which were analyzed by gas chromatography-mass spectrometry. We assessed the utility of these urine steroid profiles in detecting ACC recurrence, either when interpreted by expert clinicians or when analyzed by random forest, a machine learning-based classifier. Radiological recurrence detection served as the reference standard. RESULTS: Imaging detected recurrent disease in 42 of 135 patients; 32 had provided pre- and post-recurrence urine samples. 39 patients remained disease-free for ≥3 years. The urine "steroid fingerprint" at recurrence resembled that observed before R0 resection in the majority of cases. Review of longitudinally collected urine steroid profiles by 3 blinded experts detected recurrence by the time of radiological diagnosis in 50% to 72% of cases, improving to 69% to 92%, if a preoperative urine steroid result was available. Recurrence detection by steroid profiling preceded detection by imaging by more than 2 months in 22% to 39% of patients. Specificities varied considerably, ranging from 61% to 97%. The computational classifier detected ACC recurrence with superior accuracy (sensitivity = specificity = 81%). CONCLUSION: Urine steroid metabolomics is a promising tool for postoperative recurrence detection in ACC; availability of a preoperative urine considerably improves the ability to detect ACC recurrence.

Chronic Kidney Disease Severity Is Associated With Selective Expansion of a Distinctive Intermediate Monocyte Subpopulation.

Chronic kidney disease (CKD) affects 11-13% of the world's population and greatly increases risk of atherosclerotic cardiovascular disease (ASCVD) and death. It is characterized by systemic inflammation and disturbances in the blood leukocytes that remain incompletely understood. In particular, abnormalities in the numbers and relative proportions of the three major monocyte subsets-classical, intermediate, and non-classical-are described in CKD and end-stage renal disease. In this study, we characterized absolute numbers of blood leukocyte subtypes in adults with renal function varying from normal to advanced CKD. The primary aim was to identify monocyte subpopulations that associated most closely with current estimated glomerular filtration rate (eGFR) and subsequent rate of eGFR decline. Leucocyte and monocyte populations were enumerated by multi-color flow cytometry of whole blood and peripheral blood mononuclear cell (PBMC) samples from adults with CKD stage 1-5 (n = 154) and healthy adults (n = 33). Multiple-linear regression analyses were performed to identify associations between numbers of leucocyte and monocyte populations and clinical characteristics including eGFR and rate of eGFR decline with adjustment for age and gender. In whole blood, total monocyte and neutrophil, but not lymphocyte, numbers were higher in adults with CKD 1-5 compared to no CKD and were significantly associated with current eGFR even following correction for age. In PBMC, classical and intermediate monocyte numbers were higher in CKD 1-5 but only intermediate monocyte numbers were significantly associated with current eGFR in an age-corrected analysis. When intermediate monocytes were further sub-divided into those with mid- and high-level expression of class II MHC (HLA-DRmid and HLA-DRhi intermediate monocytes) it was found that only DRhi intermediate monocytes were increased in number in CKD 1-5 compared to no CKD and were significantly associated with eGFR independently of age among the total (No CKD + CKD 1-5) study cohort as well as those with established CKD (CKD 1-5 only). Furthermore, blood number of DRhi intermediate monocytes alone proved to be significantly associated with subsequent rate of renal functional decline. Together, our data confirm neutrophil and monocyte subset dysregulation in CKD and identify a distinct subpopulation of intermediate monocytes that is associated with higher rate of loss of kidney function.

Low DHEAS: A Sensitive and Specific Test for the Detection of Subclinical Hypercortisolism in Adrenal Incidentalomas.

CONTEXT: Subclinical hypercortisolism (SH) occurs in 5% to 30% of adrenal incidentalomas (AIs). Common screening tests for adrenocorticotropin-independent hypercortisolism have substantial false-positive rates, mandating further time and resource-intensive investigations. OBJECTIVE: To determine whether low basal dehydroepiandrosterone sulfate (DHEAS) is a sensitive and specific screening test for SH in AI. SETTING AND PATIENTS: In total, 185 patients with AI were screened for adrenal medullary (plasma metanephrines) and cortical [1 mg overnight dexamethasone suppression test (ONDST), 24-hour urinary free cortisol (UFC), serum DHEAS, plasma renin, and aldosterone] hyperfunction. Positive ONDST [≥1.8 mcg/dL (≥50 nmol/L)] and/or UFC (more than the upper limit of reference range) results were further investigated. We diagnosed SH when at least 2 of the following were met: raised UFC, raised midnight serum cortisol, 48-hour dexamethasone suppression test (DST) cortisol ≥1.8 mcg/dL (≥50 nmol/L). RESULTS: 29 patients (16%) were diagnosed with SH. Adrenocorticotropin was <10 pg/mL (<2.2 pmol/L) in all patients with SH. We calculated age- and sex-specific DHEAS ratios (derived by dividing the DHEAS by the lower limit of the respective reference range) for all patients. Receiver operating characteristic curve analyses demonstrated that a ratio of 1.12 was sensitive (>99%) and specific (91.9%) for the diagnosis of SH. Cortisol following 1 mg ONDST of 1.9 mcg/dL (53 nmol/L) was a sensitive (>99%) screening test for SH but had lower specificity (82.9%). The 24-hour UFC lacked sensitivity (69%) and specificity (72%). CONCLUSION: A single basal measurement of DHEAS offers comparable sensitivity and greater specificity to the existing gold-standard 1 mg DST for the detection of SH in patients with AIs.