{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T14:45:14Z","timestamp":1787237114665,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,6,22]],"date-time":"2023-06-22T00:00:00Z","timestamp":1687392000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Unclassified primary antibody deficiency (unPAD) is a relatively novel inborn error of immunity (IEI) condition that can vary with time to more defined entities. Since long-term follow-up (FU) studies are scarce, we aimed to provide insight into the evolutionary clinical and immunological scenario of unPAD children to adulthood and identification of biomarkers of primary immune deficiency (PID) persistence. Methods: A total of 23 pediatric unPAD patients underwent clinical and immunological FU for a mean time of 14 years (range 3\u201332 years, median 16 years). Results: UnPAD diagnosis may change over time. At the last FU, 10\/23 (44%) children matched the diagnosis of transient hypogammaglobulinemia of infancy and 13\/23 (56%) suffered from a persistent PID. In detail, an unPAD condition was confirmed in 7\/23 (30%) patients, whereas 3\/23 (13%), 2\/23 (9%), and 1\/23 (4%) were reclassified as common variable immunodeficiency, selective IgA deficiency, and isolated IgM deficiency, respectively. Low IgA, low specific antibody response to pneumococcus, and lower respiratory tract infections at diagnosis were independently associated with IEI persistence. Conclusions: Long-term monitoring of unPAD patients is required to define their outcome and possible evolution towards a definitive IEI diagnosis.<\/jats:p>","DOI":"10.3390\/jcm12134206","type":"journal-article","created":{"date-parts":[[2023,6,23]],"date-time":"2023-06-23T02:34:07Z","timestamp":1687487647000},"page":"4206","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["The Evolutionary Scenario of Pediatric Unclassified Primary Antibody Deficiency to Adulthood"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7493-5226","authenticated-orcid":false,"given":"Mayla","family":"Sgrulletti","sequence":"first","affiliation":[{"name":"Pediatric Immunopathology and Allergology Unit, Policlinico Tor Vergata, University of Tor Vergata, 00133 Rome, Italy"},{"name":"Ph.D. Program in Immunology, Molecular Medicine and Applied Biotechnology, University of Rome Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4160-3727","authenticated-orcid":false,"given":"Giorgio","family":"Costagliola","sequence":"additional","affiliation":[{"name":"Section of Clinical and Laboratory Immunology, Division of Pediatrics, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuliana","family":"Giardino","sequence":"additional","affiliation":[{"name":"Pediatric Section, Department of Translational Medical Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2397-4671","authenticated-orcid":false,"given":"Simona","family":"Graziani","sequence":"additional","affiliation":[{"name":"Pediatric Immunopathology and Allergology Unit, Policlinico Tor Vergata, University of Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabetta","family":"Del Duca","sequence":"additional","affiliation":[{"name":"Pediatric Immunopathology and Allergology Unit, Policlinico Tor Vergata, University of Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9912-7997","authenticated-orcid":false,"given":"Silvia","family":"Di Cesare","sequence":"additional","affiliation":[{"name":"Department of Systems Medicine, University of Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gigliola","family":"Di Matteo","sequence":"additional","affiliation":[{"name":"Department of Systems Medicine, University of Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5968-1945","authenticated-orcid":false,"given":"Rita","family":"Consolini","sequence":"additional","affiliation":[{"name":"Section of Clinical and Laboratory Immunology, Division of Pediatrics, Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claudio","family":"Pignata","sequence":"additional","affiliation":[{"name":"Pediatric Section, Department of Translational Medical Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Viviana","family":"Moschese","sequence":"additional","affiliation":[{"name":"Pediatric Immunopathology and Allergology Unit, Policlinico Tor Vergata, University of Tor Vergata, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1111\/cei.13629","article-title":"Effectiveness of low-dose intravenous immunoglobulin therapy in minor primary antibody deficiencies: A 2-year real-life experience","volume":"205","author":"Vivarelli","year":"2021","journal-title":"Clin. 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