{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T01:27:06Z","timestamp":1792373226504,"version":"4.4.0"},"reference-count":15,"publisher":"Walter de Gruyter GmbH","issue":"12","license":[{"start":{"date-parts":[[2025,8,1]],"date-time":"2025-08-01T00:00:00Z","timestamp":1754006400000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,17]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec id=\"j_jpem-2025-0275_abs_001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Glycerol kinase deficiency (GKD) is a rare X-linked metabolic disorder caused by pathogenic variants in the GK gene. It can be present in either isolated or complex forms and often mimics primary hyperlipidemia, leading to diagnostic challenges and unnecessary treatment. This study aims to highlight the phenotypic variability and diagnostic features of GKD through a case series.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpem-2025-0275_abs_002\">\n                    <jats:title>Case Presentation<\/jats:title>\n                    <jats:p>We describe three pediatric patients diagnosed with GKD. Two siblings with isolated GKD presented with persistent, asymptomatic hypertriglyceridemia, confirmed by glyceroluria and genetic testing revealing a hemizygous c.213_214delAT (p.Cys72Ter) mutation. The third patient, diagnosed with complex GKD, presented in infancy with multisystem involvement, including immunodeficiency, hypotonia, splenic abscesses, and elevated and creatine kinase levels. Genetic analysis revealed a 6.9\u202fMb contiguous deletion spanning Xp21.2\u2013Xp11.4. In all cases, elevated triglyceride levels were unresponsive to therapy, and serum samples lacked lipemic appearance. Lipid-lowering treatments were discontinued following diagnosis, with no adverse outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpem-2025-0275_abs_003\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This case series underscores the clinical and genetic heterogeneity of GKD. Urinary glycerol analysis and the absence of serum lipemia are key diagnostic clues. Early recognition is essential to prevent misdiagnosis and guide appropriate management, particularly in treatment-resistant hypertriglyceridemia.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1515\/jpem-2025-0275","type":"journal-article","created":{"date-parts":[[2025,7,31]],"date-time":"2025-07-31T10:57:18Z","timestamp":1753959438000},"page":"1361-1366","source":"Crossref","is-referenced-by-count":3,"title":["Pseudohypertriglyceridemia as a clue: clinical and genetic spectrum of glycerol kinase deficiency in three pediatric cases"],"prefix":"10.1515","volume":"38","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-7887-1444","authenticated-orcid":false,"given":"Cemre","family":"Kara","sequence":"first","affiliation":[{"name":"Department of Pediatrics , Ankara University Faculty of Medicine , Ankara , T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3407-967X","authenticated-orcid":false,"given":"P\u0131nar","family":"K\u0131l\u0131\u00e7da\u011f\u0131 \u00c7anakc\u0131","sequence":"additional","affiliation":[{"name":"Department of Pediatric Metabolism , Ankara University Faculty of Medicine , Ankara , T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7238-2894","authenticated-orcid":false,"given":"Engin","family":"K\u00f6se","sequence":"additional","affiliation":[{"name":"Ankara University Faculty of Medicine, Department of Pediatric Metabolism and Ankara University Rare Diseases Application and Research Center , Ankara , T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2668-0441","authenticated-orcid":false,"given":"\u015eule","family":"Haskolo\u011flu","sequence":"additional","affiliation":[{"name":"Department of Pediatric Immunology and Allergy , Ankara University Faculty of Medicine , Ankara , T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5880-1113","authenticated-orcid":false,"given":"Fatma Tuba","family":"Emino\u011flu","sequence":"additional","affiliation":[{"name":"Ankara University Faculty of Medicine, Department of Pediatric Metabolism and Ankara University Rare Diseases Application and Research Center , Ankara , T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"374","published-online":{"date-parts":[[2025,8,1]]},"reference":[{"key":"2026051215122197956_j_jpem-2025-0275_ref_001","unstructured":"Walker, AP, Muscatelli, F, Stafford, AN, Chelly, J, Dahl, N, Blomquist, HK, et al.. Mutations and phenotype in isolated glycerol kinase deficiency. Am J Hum Genet 1996;58:1205\u201311."},{"key":"2026051215122197956_j_jpem-2025-0275_ref_002","doi-asserted-by":"crossref","unstructured":"Dipple, KM, Zhang, YH, Huang, BL, McCabe, LL, Dallongeville, J, Inokuchi, T, et al.. Glycerol kinase deficiency: evidence for complexity in a single gene disorder. Hum Genet 2001;109:55\u201362. https:\/\/doi.org\/10.1007\/s004390100545.","DOI":"10.1007\/s004390100545"},{"key":"2026051215122197956_j_jpem-2025-0275_ref_003","doi-asserted-by":"crossref","unstructured":"Sjarif, DR, Ploos van Amstel, JK, Duran, M, Beemer, FA, Poll-The, BT. Isolated and contiguous glycerol kinase gene disorders: a review. 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Diseases 2025;13. https:\/\/doi.org\/10.3390\/diseases13020029.","DOI":"10.3390\/diseases13020029"},{"key":"2026051215122197956_j_jpem-2025-0275_ref_006","unstructured":"Pizza, A, Picillo, E, Onore, ME, Scutifero, M, Passamano, L, Nigro, V, et al.. Xp21 contiguous gene deletion syndrome presenting as Duchenne muscular dystrophy and glycerol kinase deficiency associated with intellectual disability: case report and review literature. Acta Myol 2023;42:24\u201330. https:\/\/doi.org\/10.36185\/2532-1900-246."},{"key":"2026051215122197956_j_jpem-2025-0275_ref_007","doi-asserted-by":"crossref","unstructured":"Rathnasiri, A, Senarathne, U, Arunath, V, Hoole, T, Kumarasiri, I, Muthukumarana, O, et al.. A rare co-occurrence of duchenne muscular dystrophy, congenital adrenal hypoplasia and glycerol kinase deficiency due to Xp21 contiguous gene deletion syndrome: case report. 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Pediatr Endocrinol Diabetes Metab 2012;18:153\u20137."},{"key":"2026051215122197956_j_jpem-2025-0275_ref_010","doi-asserted-by":"crossref","unstructured":"Kopanos, C, Tsiolkas, V, Kouris, A, Chapple, CE, Albarca Aguilera, M, Meyer, R, et al.. VarSome: the human genomic variant search engine. Bioinformatics 2019;35:1978\u201380. https:\/\/doi.org\/10.1093\/bioinformatics\/bty897.","DOI":"10.1093\/bioinformatics\/bty897"},{"key":"2026051215122197956_j_jpem-2025-0275_ref_011","doi-asserted-by":"crossref","unstructured":"Sevim, U, Fatma, D, Ihsan, E, Gulay, C, Nevin, B. A neonate with contiguous deletion syndrome in XP21. J\u00a0Pediatr Endocrinol Metab 2011;24:1095\u20138. https:\/\/doi.org\/10.1515\/jpem.2011.350.","DOI":"10.1515\/JPEM.2011.350"},{"key":"2026051215122197956_j_jpem-2025-0275_ref_012","doi-asserted-by":"crossref","unstructured":"Sargent, CA, Kidd, A, Moore, S, Dean, J, Besley, GT, Affara, NA. 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