{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T18:28:52Z","timestamp":1783103332228,"version":"3.54.6"},"reference-count":26,"publisher":"Springer Science and Business Media LLC","issue":"4","license":[{"start":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T00:00:00Z","timestamp":1756339200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T00:00:00Z","timestamp":1756339200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Alma Mater Studiorum - Universit\u00e0 di Bologna"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Hormones"],"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Glycogen storage disease type IXa (GSD IXa), caused by phosphorylase kinase mutations, primarily PHKA2, presents variably from mild hepatomegaly to severe liver dysfunction or isolated ketotic hypoglycemia. Its phenotypic overlap with other metabolic disorders complicates diagnosis, requiring genetic confirmation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed clinical, biochemical, genetic, and radiological data from patients affected by GSD IXa diagnosed at our regional metabolic disease center in Bologna (Emilia-Romagna, Italy) over recent decades and we reviewed the relevant scientific literature on the pathology.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>We report three patients with recurrent symptomatic ketotic hypoglycemia affected by PHKA2 variants of uncertain significance (VUS) and review the literature concerning GSD IXa.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>GSD IXa should be considered in the differential diagnosis even when persistent ketotic hypoglycemia is the sole presenting feature, underscoring the critical importance of clinical suspicion in such cases. Improved genetic testing has refined diagnosis, even in milder cases without hepatomegaly, while dietary management with uncooked cornstarch (CS) and extended-release cornstarch (ER-CS) effectively prevents complications and maintains good glycemic control.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s42000-025-00712-9","type":"journal-article","created":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T00:51:43Z","timestamp":1756342303000},"page":"1209-1216","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Glucose dynamics in glycogen storage disease type IXa with novel PHKA2 variants: insights from our experience and a comprehensive review of the disease spectrum"],"prefix":"10.1007","volume":"24","author":[{"given":"Federico","family":"Baronio","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giacomo","family":"Biasucci","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4573-9314","authenticated-orcid":false,"given":"Egidio","family":"Candela","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Giulia","family":"Regazzi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valeria","family":"Di Natale","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Ortolano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcello","family":"Lanari","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,8,28]]},"reference":[{"key":"712_CR1","doi-asserted-by":"publisher","first-page":"706","DOI":"10.1002\/jimd.12086","volume":"42P","author":"J Saudubray","year":"2019","unstructured":"Saudubray J, Mochel F, Lamari F, Garcia-Cazorla (2019) A. 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Ethics committee approval was not obtained because we reported the clinical cases of three individuals, we did not include any identifiable information, and we obtained written consent for publication from the patients\u2019 parents, in accordance with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. This retrospective review of patient data did not require ethical approval in accordance with the local guidelines. An ethics statement is not applicable for the systematic review because this study is based exclusively on published literature. The review was not registered. Ethical approval is not required for this study in accordance with the local guidelines.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Institutional review board statement"}},{"value":"Informed consent was obtained from all subjects involved in the study.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}},{"value":"The authors declare no conflicts of interest.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}