{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T07:06:10Z","timestamp":1774422370679,"version":"3.50.1"},"reference-count":14,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T00:00:00Z","timestamp":1774396800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Hypereosinophilic syndrome (HES) is a rare and heterogeneous disorder characterized by persistent eosinophilia and multi-organ involvement. Cutaneous manifestations are common, whereas peripheral neuropathy may be underrecognized, particularly when dermatologic symptoms predominate.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case presentation<\/jats:title>\n                    <jats:p>\n                      We report the case of a 49-year-old man with a 10-year history of recurrent pruritic papules initially managed as atopic dermatitis. Laboratory testing revealed marked eosinophilia (absolute eosinophil count: 5.29\u202f\u00d7\u202f10\n                      <jats:sup>9<\/jats:sup>\n                      \/L) and significantly elevated total immunoglobulin E (IgE) (&amp;gt;6,000\u202fIU\/mL; reference range: 0\u2013100\u202fIU\/mL). One week after initiating upadacitinib for refractory pruritus, the patient\u2019s itch severity decreased substantially, after which he more clearly perceived distal numbness and gait instability. Nerve conduction studies demonstrated a symmetric sensory-predominant axonal polyneuropathy. Skin biopsy showed eosinophilic inflammatory infiltration without evidence of vasculitis. Quantitative intraepidermal nerve fiber density (IENFD) was within the age-adjusted reference range, consistent with preserved small-fiber integrity. After comprehensive exclusion of secondary and clonal causes of eosinophilia, a diagnosis of idiopathic HES with cutaneous and peripheral nervous system involvement was established. Treatment was adjusted to mepolizumab (300\u202fmg subcutaneously every 4\u202fweeks), followed by clinical improvement in neuropathic symptoms and a reduction in eosinophil levels.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This case highlights the importance of maintaining a high index of suspicion for systemic eosinophilic disorders in patients with chronic refractory pruritus and marked eosinophilia. Severe pruritus may obscure or delay recognition of concurrent neurological symptoms; therefore, early electrophysiological evaluation should be considered when systemic involvement is suspected. Targeted anti-IL-5 therapy represents an effective treatment strategy in selected cases of HES.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmed.2026.1794649","type":"journal-article","created":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T05:39:57Z","timestamp":1774417197000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Hypereosinophilic syndrome misdiagnosed as atopic dermatitis due to refractory pruritic rash masking peripheral neuropathy"],"prefix":"10.3389","volume":"13","author":[{"given":"Huan","family":"Li","sequence":"first","affiliation":[{"name":"Department of Neurology, 970th Hospital of PLA Joint Logistic Support Force","place":["Yantai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoping","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Laboratory, 970th Hospital of PLA Joint Logistic Support Force","place":["Yantai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Caixia","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Neurology, 970th Hospital of PLA Joint Logistic Support Force","place":["Yantai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wanling","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, 970th Hospital of PLA Joint Logistic Support Force","place":["Yantai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Honglei","family":"Jia","sequence":"additional","affiliation":[{"name":"Yantai Fourth Retired Cadres' Recuperation Institute of Shandong Military Region","place":["Yantai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,3,25]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"47","DOI":"10.1182\/hematology.2022000367","article-title":"Approach to the patient with suspected hypereosinophilic syndrome","volume":"2022","author":"Klion","year":"2022","journal-title":"Hematology Am Soc Hematol Educ Program"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"607","DOI":"10.1016\/j.jaci.2012.02.019","article-title":"Contemporary consensus proposal on criteria and classification of eosinophilic disorders and related syndromes","volume":"130","author":"Valent","year":"2012","journal-title":"J Allergy Clin Immunol"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"21","DOI":"10.1016\/j.jdcr.2023.06.020","article-title":"The dermatologic and histologic spectrum of hypereosinophilic syndrome","volume":"39","author":"Long","year":"2023","journal-title":"JAAD Case Rep"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"387","DOI":"10.1097\/der.0000000000000803","article-title":"An approach to hypereosinophilic syndrome presenting with cutaneous features","volume":"33","author":"Fourzali","year":"2022","journal-title":"Dermatitis"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"1057767","DOI":"10.3389\/fneur.2022.1057767","article-title":"Distinct features of hypereosinophilic syndrome with neuropathy from eosinophilic granulomatosis with polyangiitis","volume":"13","author":"Takeuchi","year":"2022","journal-title":"Front Neurol"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"1145257","DOI":"10.3389\/fmed.2023.1145257","article-title":"Eosinophilic granulomatosis with polyangiitis - advances in pathogenesis, diagnosis, and treatment","volume":"10","author":"Fijolek","year":"2023","journal-title":"Front Med (Lausanne)"},{"key":"ref7","doi-asserted-by":"publisher","first-page":"21","DOI":"10.1007\/s40120-021-00315-7","article-title":"ANCA-associated Vasculitic neuropathies: a review","volume":"11","author":"Koike","year":"2022","journal-title":"Neurol Ther"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"451","DOI":"10.1590\/abd1806-4841.20187419","article-title":"Case for diagnosis. Erythroderma as manifestation of hypereosinophilic syndrome","volume":"93","author":"Merlotto","year":"2018","journal-title":"An Bras Dermatol"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"e1726","DOI":"10.1212\/WNL.0000000000009309","article-title":"Differential clinicopathologic features of EGPA-associated neuropathy with and without ANCA","volume":"94","author":"Nishi","year":"2020","journal-title":"Neurology"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"3052","DOI":"10.1038\/s41467-020-16859-5","article-title":"Central circuit mechanisms of itch","volume":"11","author":"Chen","year":"2020","journal-title":"Nat Commun"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"522","DOI":"10.1016\/j.neuron.2014.01.018","article-title":"Transmitting pain and itch messages: a contemporary view of the spinal cord circuits that generate gate control","volume":"82","author":"Braz","year":"2014","journal-title":"Neuron"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"1319","DOI":"10.1016\/j.jaci.2009.09.022","article-title":"Hypereosinophilic syndrome: a multicenter, retrospective analysis of clinical characteristics and response to therapy","volume":"124","author":"Ogbogu","year":"2009","journal-title":"J Allergy Clin Immunol"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"903","DOI":"10.1111\/j.1468-1331.2010.03023.x","article-title":"European Federation of Neurological Societies\/peripheral nerve society guideline on the use of skin biopsy in the diagnosis of small fiber neuropathy. Report of a joint task force of the European Federation of Neurological Societies and the peripheral nerve society","volume":"17","author":"Lauria","year":"2010","journal-title":"Eur J Neurol"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"1397","DOI":"10.1016\/j.jaci.2020.08.037","article-title":"Efficacy and safety of mepolizumab in hypereosinophilic syndrome: a phase III, randomized, placebo-controlled trial","volume":"146","author":"Roufosse","year":"2020","journal-title":"J Allergy Clin Immunol"}],"container-title":["Frontiers in Medicine"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmed.2026.1794649\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T05:40:19Z","timestamp":1774417219000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmed.2026.1794649\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,25]]},"references-count":14,"alternative-id":["10.3389\/fmed.2026.1794649"],"URL":"https:\/\/doi.org\/10.3389\/fmed.2026.1794649","relation":{},"ISSN":["2296-858X"],"issn-type":[{"value":"2296-858X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,25]]},"article-number":"1794649"}}