{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:38:45Z","timestamp":1787027925210,"version":"build-2736575974"},"reference-count":51,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,12,1]],"date-time":"2022-12-01T00:00:00Z","timestamp":1669852800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005681","name":"GENESIS PHARMA","doi-asserted-by":"publisher","award":["022833\/2022"],"award-info":[{"award-number":["022833\/2022"]}],"id":[{"id":"10.13039\/501100005681","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Besides the typical amnestic presentation, neuropathological studies indicate that Alzheimer\u2019s disease (AD) may present with atypical clinical pictures. The relative frequencies of typical and atypical or mixed presentations within the entire spectrum of AD remain unclear, while some mixed or atypical presentations may have not received adequate attention for them to be included in diagnostic criteria. We investigated the spectrum of clinical presentations in patients with the AD CSF biomarker profile (high tau and phospho-tau, low A\u03b242 levels), hospitalized in a tertiary academic center. Among 98 patients with the CSF AD profile, 46% of patients had the typical presentation of \u201chippocampal\u201d amnestic dementia. Additionally, 23.5% and 15.3% fulfilled the criteria of mixed or atypical presentations, respectively, as described in the IWG-2 criteria. The remaining 15.3% had unusual presentations, including non-logopenic (semantic and non-fluent agrammatic) primary progressive aphasia, corticobasal syndrome, and Richardson syndrome, or could be diagnosed with normal pressure hydrocephalus. Despite selection bias (academic center), atypical clinical presentations of AD may be more common than previously thought. CSF biomarkers seem to be a useful tool for antemortem identification of such patients, which is likely to affect therapeutic decisions. Some of the unusual presentations described above should be incorporated in diagnostic criteria.<\/jats:p>","DOI":"10.3390\/diagnostics12123011","type":"journal-article","created":{"date-parts":[[2022,12,1]],"date-time":"2022-12-01T05:30:46Z","timestamp":1669872646000},"page":"3011","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Recognizing Atypical Presentations of Alzheimer\u2019s Disease: The Importance of CSF Biomarkers in Clinical Practice"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2481-3060","authenticated-orcid":false,"given":"George P.","family":"Paraskevas","sequence":"first","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"},{"name":"2nd Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, \u201cAttikon\u201d University General Hospital, Rimini 1, 12462 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7432-5009","authenticated-orcid":false,"given":"Vasilios C.","family":"Constantinides","sequence":"additional","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9691-9465","authenticated-orcid":false,"given":"Fotini","family":"Boufidou","sequence":"additional","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7582-7059","authenticated-orcid":false,"given":"Ioanna","family":"Tsantzali","sequence":"additional","affiliation":[{"name":"2nd Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, \u201cAttikon\u201d University General Hospital, Rimini 1, 12462 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2197-2434","authenticated-orcid":false,"given":"Efstratios-Stylianos","family":"Pyrgelis","sequence":"additional","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgios","family":"Liakakis","sequence":"additional","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabeth","family":"Kapaki","sequence":"additional","affiliation":[{"name":"Neurochemistry and Biological Markers Unit, 1st Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, Eginition Hospital, Vass. Sophias Ave. 74, 11528 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"939","DOI":"10.1212\/WNL.34.7.939","article-title":"Clinical diagnosis of Alzheimer\u2019s disease: Report of the NINCDS-ADRDA Work Group under the auspices of Department of Health and Human Services Task Force on Alzheimer\u2019s Disease","volume":"34","author":"McKhann","year":"1984","journal-title":"Neurology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"834","DOI":"10.1212\/01.WNL.0000152982.47274.9E","article-title":"Mild cognitive impairment is related to Alzheimer pathology and cerebral infarctions","volume":"64","author":"Bennett","year":"2005","journal-title":"Neurology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1038\/nrneurol.2009.216","article-title":"Primary progressive aphasia: Clinicopathological correlations","volume":"6","author":"Grossman","year":"2010","journal-title":"Nat. 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