IWG2_criteria v.1

International Working Group (IWG) 2 Criteria for Alzheimer's Disease Diagnosis.

Konstantinos Kalliamvakos

konstantinos.kalliamvakos@cambio.se

Cambio CDS

To assist clinicians in the diagnosis of Alzheimer's Disease.

<div><p>The IWG 2 Criteria can be used to aid in the diagnosis of Alzheimer&#39;s Disease.</p><p><strong>Formula</strong></p><p>Positive diagnosis for typical AD = selection of all criteria in Part A + ≥1 item in Part B. For other types of AD including atypical, mixed, and preclinical AD, see Dubois 2014.</p><p><strong>Part A: Specific clinical phenotype (must have both)</strong>:</p><ol><li>Gradual progressive change in memory function for &gt;6 months.</li><li>Objective evidence of hippocampal amnestic syndrome* based on significantly impaired performance on episodic memory test with established specificity for AD, e.g. cued recall.</li></ol><p><strong>Part B: In-vivo evidence (must have ≥1)</strong>:</p><ul><li>CSF: decreased Aβ1-42 and increased P-tau or T-tau</li><li>Amyloid PET: increased tracer retention</li><li>Genetic testing: AD autosomal dominant mutation in PSEN1, PSEN2, or APP genes</li></ul><p>*Hippocampal amnestic syndrome may be difficult to identify in later stages, in which case in-vivo evidence of Alzheimer’s pathology in the presence of dementia syndrome may be sufficient.</p><p><strong>Exclusion criteria** for typical AD (if any are present, diagnosis is not typical AD)</strong></p><table><thead><tr><th></th><th></th></tr></thead><tbody><tr><td rowspan=2>History</td><td>Sudden onset</td></tr><tr><td>Early occurrence of gait disturbances, seizures, major and prevalent behavioral changes</td></tr><tr><td rowspan=4>Clinical features</td><td>Focal neurological features</td></tr><tr><td>Early extrapyramidal signs</td></tr><tr><td>Early hallucinations</td></tr><tr><td>Cognitive fluctuations</td></tr><tr><td rowspan=5>Other medical conditions severe enough to account for memory and related symptoms</td><td>Non-AD dementia</td></tr><tr><td>Major depression</td></tr><tr><td>Cerebrovascular disease</td></tr><tr><td>Toxic, inflammatory, and metabolic disorders, all of which may require specific investigations</td></tr><tr><td>MRI FLAIR or T2 signal changes in the medial temporal lobe that are consistent with infectious or vascular insults</td></tr></tbody></table><p>**Should also exclude concomitant pathologies (e.g. vascular lesions) and other causes of cognitive disorders or dementia.</p></div>

1. Dubois B, Feldman HH, Jacova C, et al. Advancing research diagnostic criteria for Alzheimer's disease: the IWG-2 criteria. Lancet Neurol. 2014;13(6):614-29.

EVALUATION.iwg_2_criteria.v0