Back to Authors

Langford, Carol A.

https://orcid.org/0000-0001-9498-321X

Mayo Clinic

Cleveland Clinic

Citations 71

A Randomized, Double‐Blind, Placebo‐Controlled Trial of Abatacept for the Treatment of Relapsing, Nonsevere Granulomatosis With Polyangiitis
Langford, Carol A. , Friedman, Marcia , Dehghan, Natasha, Gewurz‐Singer, Ora, Koening, Curry L. , Lin, Yih Chang, Moreland, Larry W. , Fifi‐Mah, Aurore , Forbess, Lindsy, Molloy, Eamonn, Yacyshyn, Elaine , McAlear, Carol A. , Burroughs, Cristina , Rhee, Rennie L. , Hajj‐Ali, Rula A. , Cuthbertson, David , Krischer, Jeffrey P. , Friedman, Marcia , Monach, Paul A , Specks, Ulrich , Spiera, Robert F , Yacyshyn, Elaine , Rhee, Rennie L , Jayne, David , Moreland, Larry W , Khalidi, Nader , Springer, Jason , Hellmich, Bernhard , Pagnoux, Christian , Monach, Paul A. , Flossmann, Oliver , Lanyon, Peter , Specks, Ulrich , Spiera, Robert , Jones, Rachel , Warrington, Kenneth J. , Jayne, David , Merkel, Peter A.

Arthritis & Rheumatology | June 12, 2025 | Volume: 77 | Issue: 12 | Pages: 1739-1748

10.1002/art.43272 Get It

Objective To compare the efficacy of abatacept to placebo for the treatment of relapsing, nonsevere granulomatosis with polyangiitis (GPA). Methods In this multicenter trial, eligible patients with relapsing, nonsevere GPA were randomized to receive abatacept 125 mg subcutaneously once a week or placebo, both together with prednisone 30 mg/day (or equivalent), tapered and discontinued at week 12. Patients already taking methotrexate, azathioprine, mycophenolate, or leflunomide continued this medication at a stable dose. Patients achieving remission remained on their randomized assignment until relapse, early termination, or the common close date 12 months after enrollment of the last patient. Those who had a nonsevere relapse, had nonsevere worsening, or were not in remission by month 6 had the option to receive open‐label abatacept. The primary end point was the rate of treatment failure, defined as relapse, disease worsening, or failure to achieve a Birmingham Vasculitis Activity Score for Wegener's Granulomatosis (BVAS/WG) of 0 or 1 by six months. Results Sixty‐five patients were randomized; 34 received abatacept and 31 received placebo. No statistical difference in the treatment failure rate was found between those who received abatacept and those who received placebo ( P = 0.853). Treatment with abatacept did not demonstrate any statistical difference from placebo in key secondary end points, including time to full remission (BVAS/WG = 0), duration of glucocorticoid‐free remission, relapse severity, prevention of damage, and patient‐reported quality‐of‐life outcomes. There was no difference in the frequency or severity of adverse events between treatment arms, including infection. Conclusion In patients with relapsing, nonsevere GPA, abatacept did not reduce the risk of relapse, severe worsening, or failure to achieve remission.
Assessment of damage in Takayasu’s arteritis
Kermani, Tanaz A. , Sreih, Antoine G. , Cuthbertson, David , Koening, Curry L. , Langford, Carol A. , McAlear, Carol A. , Moreland, Larry W. , Rhee, Rennie L. , Rhee, Rennie L , Warrington, Kenneth J , Moreland, Larry W , Khalidi, Nader , Monach, Paul A. , Pagnoux, Christian , Seo, Philip , Warrington, Kenneth J. , Merkel, Peter A.

Rheumatology | June 13, 2024 | Volume: 64 | Issue: 2 | Pages: 682-689

10.1093/rheumatology/keae333 Get It

Abstract Objectives To evaluate damage and clinical characteristics associated with damage in Takayasu’s arteritis (TAK). Methods Patients with TAK enrolled in a multicentre, prospective, observational study underwent standardized damage assessment every 6 months using the Vasculitis Damage Index (VDI) and the Large-Vessel Vasculitis Index of Damage (LVVID). Results The study included 236 patients with TAK: 92% female, 81% Caucasian; median (25th, 75th percentile) disease duration = 2.6 (0.12, 6.9) years. Eighty-four percent had follow-up: median (25th, 75th) duration 4.1 (1.9, 7.5) years. Items of damage were present in 89% on VDI, 87% on LVVID, in the peripheral vascular (76% VDI, 74% LVVID) and cardiac (40% VDI, 45% LVVID) systems. During follow-up, 42% patients had new damage, including major vessel stenosis/arterial occlusion (8%), limb claudication (6%), hypertension (7%), aortic aneurysm (4%) and bypass surgery (4%). Disease-specific damage accounted for >90% of new items. Older age, relapse and longer duration of follow-up were associated with new damage items; a higher proportion of patients without new damage were on MTX (P <0.05). Among 48 patients diagnosed with TAK within 180 days of enrolment, new damage occurred in 31% on VDI and 52% on LVVID. History of relapse was associated with new damage in the entire cohort while in patients with a recent diagnosis, older age at diagnosis was associated with new damage. Conclusion Damage is present in >80% of patients with TAK even with recent diagnosis and >40% of patients accrue new, mainly disease-specific damage. Therapies for TAK that better control disease activity and prevent damage should be prioritized.
Clinical Characteristics and Outcomes of Polyarteritis Nodosa: An International Study
Karadağ, Ömer , Bölek, Ertuğrul Çağrı , Ayan, Gizem , Mohammad, Aladdin J , Grayson, Peter C. , Pagnoux, Christian , Martín‐Nares, Eduardo , Monti, Sara , Abe, Yoshiyuki , Alberici, Federico , Alıbaz-Öner, Fatma , Cuthbertson, David , Koening, Curry L. , Langford, Carol A. , McAlear, Carol A. , Hočevar, Alojzija , Hinojosa‐Azaola, Andrea , Furuta, Shunsuke , Emmi, Giacomo , Özen, Seza , Collaborators, for the GLOBAL‐PAN, Springer, Jason , Simonini, Gabriele , Di̇reskeneli̇, Haner , Khalidi, Nader A , McAlear, Carol A , Warrington, Kenneth J , Hocevar, Alojzija , Hinojosa-Azaola, Andrea , Ozen, Seza , Jayne, David , Merkel, Peter A , Springer, Jason M , Monti, Sara , Pagnoux, Christian , Mohammad, Aladdin J , Dagna, Lorenzo , Khalidi, Nader , Monach, Paul A. , Moroni, Luca , Padoan, Roberto , Seo, Philip , Warrington, Kenneth J. , Jayne, David , Merkel, Peter A. , Collaborators, for the GLOBAL‐PAN

Arthritis & Rheumatology | February 12, 2024 | Volume: 76 | Issue: 7 | Pages: 1120-1129

10.1002/art.42817 Get It

Objective We describe the demographics, clinical features, disease course, and survival of polyarteritis nodosa (PAN) through an international collaboration (GLOBAL‐PAN). Methods Patients with PAN were recruited between 1990 and 2020 from observational cohorts of nine countries across Europe, Japan, and North America. Eligibility was retrospectively defined using the European Medicines Agency classification algorithm. Patients with PAN related to hepatitis B virus (n = 12) and two monogenic diseases mimicking PAN, deficiency of adenosine deaminase 2 enzyme (n = 16) or familial Mediterranean fever (n = 11), were excluded. Data regarding organ involvement, relapse, disease‐related damage, and survival were analyzed. Results Three hundred fifty‐eight patients (female:male ratio 174:184), including those with systemic PAN (sPAN, n = 282) and cutaneous PAN (n = 76), were included. Twenty‐five were pediatric onset. Mean ± SD age at diagnosis was 44.3 ± 18.1 years. Constitutional symptoms (71.5%), cutaneous involvement (70.5%), musculoskeletal findings (69.1%), and neurologic features (48.0%) were common manifestations. Among patients with sPAN, gastrointestinal involvement and proteinuria over 400 mg/day were reported in 52.2% and 11.2%, respectively. During a median (interquartile range) 59.6 (99.5) months of follow‐up, relapse occurred in 48.5% of patients. One, 5‐ and 10‐year survival rates for sPAN were 97.1%, 94.0%, and 89.0%, respectively. Predictors of death for sPAN included age ≥65 years at diagnosis, serum creatinine at diagnosis >140 μmol/L, gastrointestinal manifestations, and central nervous system (CNS) involvement. Conclusion The spectrum of PAN remains a complex, multifaceted disease. Relapse is common. Age ≥65 years and serum creatinine >140 μmol/L at diagnosis, as well as gastrointestinal and CNS involvement, are independent predictors of death in sPAN. image
The Association Between Age at Diagnosis and Disease Characteristics and Damage in Patients With ANCA‐Associated Vasculitis
Bloom, Jessica L. , Pickett‐Nairn, Kaci, Silveira, Lori , Fuhlbrigge, Robert C. , Cuthbertson, David , Akuthota, Praveen , Corbridge, Thomas, Koening, Curry L. , Langford, Carol A. , McAlear, Carol A. , Rhee, Rennie L. , Silver, Jared , Monach, Paul A , Rhee, Rennie L , Merkel, Peter A , Khalidi, Nader , Monach, Paul A. , Moreland, Larry W. , Pagnoux, Christian , Seo, Philip , Specks, Ulrich , Warrington, Kenneth J. , Wechsler, Michael E , Merkel, Peter A.

Arthritis & Rheumatology | July 11, 2023 | Volume: 75 | Issue: 12 | Pages: 2216-2227

10.1002/art.42651 Get It

ObjectiveThis study examined the relationship between age at diagnosis and disease characteristics and damage in patients with antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV).MethodsAnalysis of a prospective longitudinal cohort of patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA) in the Vasculitis Clinical Research Consortium (2013–2021). Disease cohorts were divided by age at diagnosis (years): children (<18), young adults (18–40), middle‐aged adults (41–65), and older adults (>65). Data included demographics, ANCA type, clinical characteristics, Vasculitis Damage Index (VDI) scores, ANCA Vasculitis Index of Damage (AVID) scores, and novel disease‐specific and non‐disease‐specific damage scores built from VDI and AVID items.ResultsAnalysis included data from 1020 patients with GPA/MPA and 357 with EGPA. Female predominance in GPA/MPA decreased with age at diagnosis. AAV in childhood was more often GPA and proteinase 3‐ANCA positive. Children with GPA/MPA experienced more subglottic stenosis and alveolar hemorrhage; children and young adults with EGPA experienced more alveolar hemorrhage, need for intubation, and gastrointestinal involvement. Older adults (GPA/MPA) had more neurologic manifestations. After adjusting for disease duration, medications, tobacco, and ANCA, all damage scores increased with age at diagnosis for GPA/MPA (P < 0.001) except the disease‐specific damage score, which did not differ (P = 0.44). For EGPA, VDI scores increased with age at diagnosis (P < 0.009), whereas all other scores were not significantly different.ConclusionAge at diagnosis is associated with clinical characteristics in AAV. Although VDI and AVID scores increase with age at diagnosis, this is driven by non‐disease‐specific damage items.image
A Transcriptomic Signature of Mepolizumab Response in Eosinophilic Granulomatosis With Polyangiitis (EGPA)
Carey, V., Chase, R., Stankiewicz, S., Weller, P F, Langford, Carol A. , Dyer, A., Specks, U., Gleich, Gerald J. , Calyton, F., Wechsler, M.E., Raby, Benjamin A. , Baek, Seung Han , Khoury, Paneez , Maiorino, Enrico , Glass, Kimberly , Chase, R., Merkel, Peter A. , Specks, Ulrich , Klion, Amy D. , Akuthota, Praveen

A31. GLOBAL AND ENVIRONMENTAL INFLUENCES IN ASTHMA | May 1, 2023 | Volume: No volume available | Issue: No issue available | Pages: A1318-A1318

10.1164/ajrccm-conference.2023.207.1_meetingabstracts.a1318 Get It

Vitamin D status in ANCA-associated vasculitis
Doubelt, Irena , Cuthbertson, David , Carette, Simon , Koening, Curry L. , Langford, Carol A. , McAlear, Carol A. , Moreland, Larry W. , Warrington, Kenneth J , Pagnoux, Christian , Moreland, Larry W , Khalidi, Nader , Monach, Paul A. , Seo, Philip , Specks, Ulrich , Warrington, Kenneth J. , Merkel, Peter A. , Pagnoux, Christian

Rheumatology Advances in Practice | February 10, 2023 | Volume: 7 | Issue: 1 | Pages: No page available

10.1093/rap/rkad021 Get It

AbstractObjectiveVitamin D might participate in the pathogenesis of several immune-mediated diseases, but few related data are available for ANCA-associated vasculitis (AAV). In this study, we analysed the association between vitamin D status and disease in patients with AAV.MethodsSerum levels of 25(OH)D2/3 were measured in 125 randomly selected patients with AAV [granulomatosis with polyangiitis (n = 50), eosinophilic granulomatosis with polyangiitis (n = 50) or microscopic polyangiitis (n = 25)] enrolled in the Vasculitis Clinical Research Consortium Longitudinal Studies at the time of enrolment and a subsequent relapse visit. Sufficient, insufficient and deficient vitamin D status were defined as 25(OH)D3 levels &gt;30, 20–30 and ˂20 ng/ml, respectively.ResultsSeventy of 125 patients (56%) were female, with a mean age of 51.5 (16) years at diagnosis; 84 (67%) were ANCA positive. Mean 25(OH)D was 37.6 (16) ng/ml, with vitamin D deficiency in 13 (10.4%) and insufficiency in 26 (20.8%). In univariate analysis, lower vitamin D status was associated with male sex (P = 0.027) and disease activity (P = 0.047). In univariate and multivariate analyses, deficient vitamin D status was associated with disease activity (P = 0.015). Mean 25(OH)D status in the 21 patients with a subsequent relapse did not differ between baseline and relapse visit [37.8 (16) vs 38.0 (10) ng/ml, respectively; P = 0.92].ConclusionMost patients with AAV have sufficient 25(OH)D levels, although those with lower vitamin D status were more likely to be male and to have active disease. Whether optimization of vitamin D status alters disease manifestations or activity in AAV remains to be determined.Trial RegistrationVasculitis Clinical Research Consortium (VCRC) Longitudinal Study (LS), NCT00315380, https://clinicaltrials.gov/ct2/show/NCT00315380
Activation of a Latent Epitope Causing Differential Binding of Antineutrophil Cytoplasmic Antibodies to Proteinase 3
Moura, Marta Casal , Thompson, Gwen , Nelson, Darlene R. , Fussner, Lynn A. , Hummel, Amber M., Jenne, Dieter E. , Emerling, Daniel , Kallenberg, Cees G. M., Langford, Carol A. , McCune, W. Joseph, Clair, E. William St. , Ytterberg, Steven R. , Stone, John H. , Robinson, William H. , Casal Moura, Marta , Thompson, Gwen E, Merkel, Peter A , Monach, Paul A , Spiera, Robert F , Stone, John H , Robinson, William H , Fervenza, Fernando C. , Merkel, Peter A. , Monach, Paul A. , Seo, Philip , Spiera, Robert , Specks, Ulrich

Arthritis & Rheumatology | December 14, 2022 | Volume: 75 | Issue: 5 | Pages: 748-759

10.1002/art.42418 Get It

Objective Proteinase 3 (PR3) is the major antigen for antineutrophil cytoplasmic antibodies (ANCAs) in the systemic autoimmune vasculitis, granulomatosis with polyangiitis (GPA). PR3‐targeting ANCAs (PR3‐ANCAs) recognize different epitopes on PR3. This study was undertaken to study the effect of mutations on PR3 antigenicity. Methods The recombinant PR3 variants, iPR3 (clinically used to detect PR3‐ANCAs) and iHm5 (containing 3 point mutations in epitopes 1 and 5 generated for epitope mapping studies) immunoassays and serum samples from patients enrolled in ANCA‐associated vasculitis (AAV) trials were used to screen for differential PR3‐ANCA binding. A patient‐derived monoclonal ANCA 518 (moANCA518) that selectively binds to iHm5 within the mutation‐free epitope 3 and is distant from the point mutations of iHm5 was used as a gauge for remote epitope activation. Selective binding was determined using inhibition experiments. Results Rather than reduced binding of PR3‐ANCAs to iHm5, we found substantially increased binding of the majority of PR3‐ANCAs to iHm5 compared to iPR3. This differential binding of PR3‐ANCA to iHm5 is similar to the selective moANCA518 binding to iHm5. Binding of iPR3 to monoclonal antibody MCPR3‐2 also induced recognition by moANCA518. Conclusion The preferential binding of PR3‐ANCAs from patients, such as the selective binding of moANCA518 to iHm5, is conferred by increased antigenicity of epitope 3 on iHm5. This can also be induced on iPR3 when captured by monoclonal antibody MCPR2. This previously unrecognized characteristic of PR3‐ANCA interactions with its target antigen has implications for studying antibody‐mediated autoimmune diseases, understanding variable performance characteristics of immunoassays, and design of potential novel treatment approaches. image
Ocular manifestations of ANCA-associated vasculitis
Junek, Mats , Zhao, Lily, Garner, Stephanie , Cuthbertson, David , Pagnoux, Christian , Koening, Curry L. , Langford, Carol A. , McAlear, Carol A. , Moreland, Larry W. , Rhee, Rennie L. , Sreih, Antoine G. , Junek, Mats L , Warrington, Kenneth J , Moreland, Larry W , Pagnoux, Christian , Monach, Paul A. , Seo, Philip , Specks, Ulrich , Warrington, Kenneth J. , Wechsler, Michael E , Merkel, Peter A. , Khalidi, Nader

Rheumatology | November 23, 2022 | Volume: 62 | Issue: 7 | Pages: 2517-2524

10.1093/rheumatology/keac663 Get It

Abstract Objectives ANCA-associated vasculitis (AAV) is a group of multisystem diseases that can have several ocular manifestations. There are published data on ocular manifestations of granulomatosis with polyangiitis (GPA), but few for eosinophilic granulomatosis with polyangiitis (EGPA) or microscopic polyangiitis (MPA). There is little information concerning chronicity, complications, and association with other cranial manifestations of AAV. Methods This study retrospectively analysed longitudinal multicentre cohorts of individuals with AAV followed between 2006 and 2022. Data included diagnosis, demographics, cranial manifestations of disease, presence of manifestations at onset of disease and/or follow-up, and ocular complications of disease. Univariate and multivariable logistic regression analysis assessed associations across disease manifestations. Results Data from 1441 patients were analysed, including 395 with EGPA, 876 with GPA, and 170 with MPA. Ocular manifestations were seen within 23.1% of patients: 39 (9.9%) with EGPA, 287 (32.7%) with GPA, and 12 (7.1%) with MPA at any time in the disease course. There were more ocular manifestations at onset (n = 224) than during follow-up (n = 120). The most common disease-related manifestations were conjunctivitis/episcleritis and scleritis. In multivariable analysis, dacryocystitis, lacrimal duct obstruction, and retro-orbital disease were associated with sinonasal manifestations of GPA; ocular manifestations were associated with hearing loss in MPA. The most common ocular complications and/or damage seen were cataracts (n = 168) and visual impairment (n = 195). Conclusion Ocular manifestations occur in all forms of AAV, especially in GPA. Clinicians should be mindful of the wide spectrum of ocular disease in AAV, caused by active vasculitis, disease-associated damage, and toxicities of therapy.
Autoreactive Plasmablasts After B Cell Depletion With Rituximab and Relapses in Antineutrophil Cytoplasmic Antibody–Associated Vasculitis
Berti, Alvise , Hillion, Sophie , Konig, Maximilian F. , Moura, Marta Casal , Hummel, Amber M., Carmona, Eva M. , Peikert, Tobias, Kallenberg, Cees G. M., Langford, Carol A. , Brunetta, Paul , Clair, E. William St. , Harris, Kristina M. , Stone, John H. , Grandi, Guido, Carmona, Eva, Monach, Paul A , Spiera, Robert F , Stone, John H , Pers, Jacques-Olivier , Specks, Ulrich , Cornec, Divi , Carmona, Eva M , Casal Moura, Marta , Berti, Alvise , Fervenza, Fernando C. , Merkel, Peter A. , Monach, Paul A. , Seo, Philip , Spiera, Robert , Grandi, Guido, Specks, Ulrich

Arthritis & Rheumatology | October 25, 2022 | Volume: 75 | Issue: 5 | Pages: 736-747

10.1002/art.42388 Get It

ObjectiveAutoreactive B cells are responsible for antineutrophil cytoplasmic antibody (ANCA) production in ANCA‐associated vasculitis (AAV). Rituximab (RTX) depletes circulating B cells, including autoreactive B cells. We aimed to evaluate changes and associations with relapse of the circulating autoreactive B cell pool following therapeutic B cell depletion in AAV.MethodsSequential flow cytometry was performed on 148 samples of peripheral blood mononuclear cells from 23 patients with proteinase 3 (PR3)–ANCA–positive AAV who were treated with RTX for remission induction and monitored after stopping therapy during long‐term follow‐up in a prospective clinical trial. PR3 was used as a ligand to target autoreactive PR3‐specific (PR3+) B cells. B cell recurrence was considered as the first blood sample with ≥10 B cells/μl after RTX treatment.ResultsAt B cell recurrence, PR3+ B cell frequency among B cells was higher than baseline (P < 0.01). Within both PR3+ and total B cells, frequencies of transitional and naive subsets were higher at B cell recurrence than at baseline, while memory subsets were lower (P < 0.001 for all comparisons). At B cell recurrence, frequencies of B cells and subsets did not differ between patients who experienced relapse and patients who remained in remission. In contrast, the plasmablast frequency within the PR3+ B cell pool was higher in patients who experienced relapse and associated with a shorter time to relapse. Frequencies of PR3+ plasmablasts higher than baseline were more likely to be found in patients who experienced relapse within the following 12 months compared to those in sustained remission (P < 0.05).ConclusionThe composition of the autoreactive B cell pool varies significantly following RTX treatment in AAV, and early plasmablast enrichment within the autoreactive pool is associated with future relapses.
Urine eosinophil‐derived neurotoxin: A potential marker of activity in select eosinophilic disorders
Makiya, Michelle , Khoury, Paneez , Kuang, Fei Li , Mata, Alexis Dominique , Mahmood, Sana , Bowman, Abbie, Kovacs, Nicholas A. , Holland, Nicole, Dyer, Anne‐Marie , Akuthota, Praveen , Gleich, Gerald J. , Langford, Carol A. , Weller, Peter F. , Makiya, Michelle A , Wetzler, Lauren , Dyer, Anne-Marie , Bochner, Bruce S , Chinchilli, Vernon M , Gleich, Gerald J , Merkel, Peter A , Specks, Ulrich , Weller, Peter F , Wechsler, Michael E , Prussin, Calman , Klion, Amy D , Mahmood, Sana, Espinoza, David, Kovacs, Nicholas, Brown, Thomas , Ware, JeanAnne M. , Bochner, Bruce S. , Merkel, Peter A. , Specks, Ulrich , Fay, Michael P. , Klion, Amy D.

Allergy | August 16, 2022 | Volume: 78 | Issue: 1 | Pages: 258-269

10.1111/all.15481 Get It

AbstractBackgroundBiomarkers of eosinophilic disease activity, especially in the context of novel therapies that reduce blood eosinophil counts, are an unmet need. Absolute eosinophil count (AEC) does not accurately reflect tissue eosinophilia or eosinophil activation. Therefore, the aims of this study were to compare the reliability of plasma and urine eosinophil major basic protein 1, eosinophil cationic protein, eosinophil‐derived neurotoxin (EDN), and eosinophil peroxidase measurement and to evaluate the usefulness of eosinophil granule protein (EGP) measurement for the assessment of disease activity in patients with eosinophil‐associated diseases treated with mepolizumab, benralizumab, or dexpramipexole.MethodsEosinophil granule protein concentrations were measured in serum, plasma, and urine from healthy volunteers and patients with hypereosinophilic syndrome (HES), eosinophilic granulomatosis with polyangiitis (EGPA), and eosinophilic asthma using a multiplex assay.ResultsUrine EGP concentrations remained stable, whereas serum and plasma EGP concentrations increased significantly with delayed processing. Plasma (p) EDN, but not urine (u) EDN, concentration correlated with AEC and negatively correlated with prednisone dose. Both pEDN and uEDN decreased significantly following treatment of HES patients with benralizumab and EGPA patients with mepolizumab. uEDN appeared to increase with clinical relapse in both patient groups.ConclusionsMeasurement of EGP in urine is noninvasive and unaffected by cellular lysis. Although plasma and urine EDN concentrations showed a similar pattern following benralizumab and mepolizumab treatment, the lack of correlation between AEC or prednisone dose and uEDN concentrations suggests that measurement of uEDN may provide a potential biomarker of disease activity in patients with HES and EGPA.