{"id":"haptoglobin","name":"Haptoglobin","shortName":"Haptoglobin","aliases":["Hapto","Haptoglobin, Serum","Haptoglobin Level","HAPT","Haptoglobin Quant","Haptoglobin, Quantitative","Haptoglobin, Plasma","Haptoglobin, S","Haptoglobin Concentration","Haptoglobina"],"abbreviations":["HAPT","Hapto"],"loinc":[{"code":"4542-7","primary":true},{"code":"46127-7","primary":false},{"code":"4543-5","primary":false},{"code":"70209-2","primary":false}],"specimen":"serum-or-plasma","units":[{"ucum":"mg/dL","display":"mg/dL"},{"ucum":"g/L","display":"g/L"}],"referenceRanges":[{"population":"Adults","low":30,"high":200,"unit":"mg/dL","unitDisplay":"mg/dL","note":"Same adult interval published by ARUP (quantitative immunoturbidimetry), Mayo Clinic Laboratories (nephelometry, listed through the MHCC Laboratory catalog) and the University of Iowa hospital laboratory (immunoturbidimetric). None of the three splits it by sex or age. Other labs and methods print different limits, for example Michigan Medicine prints 22–239 mg/dL (immunoturbidimetric). A low result is not always a sign of illness: children's levels are often naturally low, healthy volunteers in Nigeria had lower levels than usual Western intervals, and an inherited gene deletion can cause very low or missing haptoglobin. Cirrhosis, high estrogen, diluted blood and poor sample handling can also lower it. In one study of 100 patients, 25 mg/dL or less separated hemolytic from non-hemolytic disorders with 83% sensitivity and 96% specificity. Use the range printed on your own report.","sources":[{"title":"Haptoglobin (test 0050280)","url":"https://ltd.aruplab.com/Tests/Pub/0050280","publisher":"ARUP Laboratories"},{"title":"Haptoglobin, Serum (test HAPT), Mayo Clinic Laboratories, as listed in the MHCC Laboratory catalog","url":"https://mhcclab.testcatalog.org/show/HAPT","publisher":"MHCC Laboratory (catalog powered by Mayo Clinic Laboratories)"},{"title":"Haptoglobin (Pathology Handbook)","url":"https://www.healthcare.uiowa.edu/path_handbook/handbook/test934.html","publisher":"University of Iowa Hospitals & Clinics"},{"title":"Haptoglobin (MLabs test information)","url":"https://mlabs.umich.edu/tests/haptoglobin","publisher":"Michigan Medicine Clinical Laboratories (MLabs)"},{"title":"Clinical Applications of Hemolytic Markers in the Differential Diagnosis and Management of Hemolytic Anemia","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC4706896/","publisher":"Disease Markers","year":2015},{"title":"Haptoglobin testing in hemolysis: measurement and interpretation","url":"https://pubmed.ncbi.nlm.nih.gov/24809098/","publisher":"American Journal of Hematology","year":2014},{"title":"The haptoglobin-gene deletion responsible for anhaptoglobinemia","url":"https://pubmed.ncbi.nlm.nih.gov/9463309/","publisher":"American Journal of Human Genetics","year":1998},{"title":"Ahaptoglobinaemia in a Nigerian Cohort","url":"https://pubmed.ncbi.nlm.nih.gov/30091729/","publisher":"Nigerian Journal of Physiological Sciences","year":2018},{"title":"Reference intervals for haptoglobin in neonates and children 30 days to 18 years old","url":"https://pubmed.ncbi.nlm.nih.gov/42227564/","publisher":"Scandinavian Journal of Clinical and Laboratory Investigation","year":2026}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A protein made by the liver that binds free hemoglobin. A low level can be a clue that red blood cells are breaking down faster than normal.","url":"https://bloodtesttracker.com/markers/haptoglobin","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}