{"id":"crp","name":"C-Reactive Protein (CRP, incl. hs-CRP)","shortName":"CRP","aliases":["C-Reactive Protein","CRP","hs-CRP","High Sensitivity CRP","hsCRP","C-Reactive Protein, Cardiac","C-Reactive Protein, Quantitative","CRP, High Sensitivity","Proteína C reactiva","PCR (proteína C reactiva)","C Reactive Protein","C-Reactive Protein, High Sensitivity","C-Reactive Protein, HS","High-Sensitivity C-Reactive Protein","C-Reactive Protein, Quant","CRP, Quantitative","CRP, Quant","CRP, Cardiac","Cardiac CRP","CRP, Serum","C-Reactive Protein, Serum","HS CRP","CRP-hs","CRP (hs)","Ultra-sensitive CRP","Ultrasensitive C-Reactive Protein","Sensitive CRP","C-Reactive Protein, Sensitive Cardio","C-Reactive Protein, Cardio","C-Reactive Prot, High Sens, Serum","PCR ultrasensible","Proteína C reactiva ultrasensible","C-reaktives Protein","Protéine C réactive"],"abbreviations":["CRP","hs-CRP","hsCRP"],"loinc":[{"code":"30522-7","primary":true},{"code":"1988-5","primary":false},{"code":"71426-1","primary":false},{"code":"105126-7","primary":false},{"code":"48421-2","primary":false}],"specimen":"serum-or-plasma","units":[{"ucum":"mg/L","display":"mg/L"},{"ucum":"mg/dL","display":"mg/dL"},{"ucum":"ug/mL","display":"µg/mL"}],"referenceRanges":[{"population":"Adults","low":0,"high":5,"unit":"mg/L","unitDisplay":"mg/L","note":"Standard-CRP limit used by Mayo Clinic Laboratories (under 5.0 mg/L, all ages) and ARUP (under 0.5 mg/dL). Labcorp prints 0–10 mg/L for adults, and MedlinePlus calls 0.8 to 1.0 mg/dL (8 to 10 mg/L) or lower a healthy amount. Labcorp's intervals for ages 1 month to 17 years are 0–7 mg/L (male) and 0–9 mg/L (female). For hs-CRP, ARUP's interval is 3.0 mg/L or less and Mayo's is under 2.0 mg/L (age 18 and older), so also look at the heart-risk groups under Bands. In healthy young blood donors the median is about 0.8 mg/L, the 90th percentile is 3.0 and the 99th is 10 (Pepys 2003), and about one in three Americans falls between 3 and 10 mg/L (Kushner 2006). Levels run higher on average in women and with age (Khera 2005, Wener 2000) and in late pregnancy (median about 4.1 mg/L in the third trimester in one study of 100 healthy women), so a lab's usual range can flag values that are typical for these groups.","sources":[{"title":"C-Reactive Protein (CRP), Serum (Mayo test ID CRP)","url":"https://schnecklab.testcatalog.org/show/CRP","publisher":"Mayo Clinic Laboratories (catalog page mirrored on testcatalog.org)"},{"title":"C-Reactive Protein (ARUP test 0050180)","url":"https://ltd.aruplab.com/Tests/Pub/0050180","publisher":"ARUP Laboratories"},{"title":"C-Reactive Protein (CRP), Quantitative (test 006627)","url":"https://www.labcorp.com/tests/006627/c-reactive-protein-quantitative","publisher":"Labcorp"},{"title":"C-Reactive Protein, High Sensitivity, Serum (Mayo test ID HSCRP)","url":"https://schnecklab.testcatalog.org/show/HSCRP","publisher":"Mayo Clinic Laboratories (catalog page mirrored on testcatalog.org)"},{"title":"C-Reactive Protein, High Sensitivity (ARUP test 0050182)","url":"https://ltd.aruplab.com/Tests/Pub/0050182","publisher":"ARUP Laboratories"},{"title":"C-Reactive Protein (CRP) Test","url":"https://medlineplus.gov/lab-tests/c-reactive-protein-crp-test/","publisher":"MedlinePlus (National Library of Medicine)"},{"title":"C-reactive protein: a critical update","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC161431/","publisher":"Journal of Clinical Investigation","year":2003},{"title":"What does minor elevation of C-reactive protein signify?","url":"https://pubmed.ncbi.nlm.nih.gov/16443421/","publisher":"American Journal of Medicine","year":2006},{"title":"Race and gender differences in C-reactive protein levels","url":"https://pubmed.ncbi.nlm.nih.gov/16053959/","publisher":"Journal of the American College of Cardiology","year":2005},{"title":"The influence of age, sex, and race on the upper reference limit of serum C-reactive protein concentration","url":"https://pubmed.ncbi.nlm.nih.gov/11036829/","publisher":"Journal of Rheumatology","year":2000},{"title":"Plasma C-Reactive Protein and Pentraxin-3 Reference Intervals During Normal Pregnancy","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC8366313/","publisher":"Frontiers in Immunology","year":2021}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A protein your liver makes when the body has inflammation. Standard CRP helps check for infection or injury, and hs-CRP is used in heart-risk checks.","url":"https://bloodtesttracker.com/markers/crp","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}