{"id":"atypical-lymphocytes-percent","name":"Atypical (Reactive) Lymphocytes (Percent)","shortName":"Atypical lymphs %","aliases":["Atypical Lymphocytes","Reactive Lymphocytes","Variant Lymphocytes","Atypical Lymphs","Atyp Lymphs","Reactive Lymphs %","Atypical Lymphocytes %","Atypical (Reactive) Lymphocytes","Reactive Lymphocytes (%)","Variant Lymphocytes (%)","Reactive Lymphs","Variant Lymphs","Downey Cells","Linfocitos atípicos","Linfócitos atípicos","Atypische Lymphozyten"],"abbreviations":["VAR LYM"],"loinc":[{"code":"13046-8","primary":true},{"code":"735-1","primary":false},{"code":"42250-1","primary":false},{"code":"71665-4","primary":false}],"specimen":"whole-blood","units":[{"ucum":"%","display":"%"},{"ucum":"1","display":"fraction (0–1)"}],"referenceRanges":[{"population":"12+","low":0,"high":2,"unit":"%","unitDisplay":"%","note":"From one lab: the Children's Hospital of Philadelphia lists 0.0–2.0% for ages 12 and over, with the same interval for both sexes. No second lab was found that publishes a comparable limit. OHSU lists 0 for 'atypical cells %' at all ages, but that label may include other abnormal cells, so it is not counted as agreement. Other labs may use different limits, may call the cells reactive or variant, or may not report them at all, so use the range printed on your own report.","sources":[{"title":"Laboratory Reference Ranges (Hematology Laboratory differential reference ranges), reviewed April 17, 2024","url":"https://www.chop.edu/sites/default/files/2024-06/chop-labs-reference-ranges.pdf","publisher":"Children's Hospital of Philadelphia, Pathology and Laboratory Medicine","year":2024}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"The share of your white blood cells that are lymphocytes with an 'activated' look under the microscope, most often because your immune system is responding to a virus.","url":"https://bloodtesttracker.com/markers/atypical-lymphocytes-percent","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}