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Order Code MET Methemoglobin and Sulfhemoglobin, Blood

Reporting Name

Methemoglobin and Sulfhemoglobin, B

Useful For

Diagnosing methemoglobinemia and sulfhemoglobinemia


Identifying cyanosis due to other causes, such as congenital heart disease

Profile Information

Test ID Reporting Name Available Separately Always Performed
METH Methemoglobin, B No Yes
SULF Sulfhemoglobin, B No Yes

Performing Laboratory

Mayo Medical Laboratories in Rochester

Specimen Type

Whole Blood EDTA

Specimen Required

Specimen must arrive within 72 hours of draw.


Container/Tube: Lavender top (EDTA)  

Specimen Volume: Full tube

Additional Information: Patient's age is required.

Forms: If not ordering electronically, complete, print, and send a Benign Hematology Test Request Form (T755) with the specimen (

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time
Whole Blood EDTA Refrigerated 72 hours

Reference Values


0-11 months: not established

≥1 year: 0.0-1.5% of total hemoglobin



0-11 months: not established

≥1 year: 0.0-0.4% of total hemoglobin

Day(s) and Time(s) Performed

Monday through Saturday; Continuously

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information



LOINC Code Information

Test ID Test Order Name Order LOINC Code
MET Methemoglobin and Sulfhemoglobin, Blood In Process


Result ID Test Result Name Result LOINC Code
8268 Methemoglobin, B 2614-6
8272 Sulfhemoglobin, B 4685-4


Methemoglobin is unstable and is reduced to hemoglobin at a rate of about 40% per day at 0 to 4° C.


A normal methemoglobin value obtained with stored or shipped specimens does not exclude prior mild methemoglobinemia. However, significant methemoglobinemia will still be demonstrable.


Sulfhemoglobin is stable and does not change in stored or shipped specimens.

Analytic Time

Same day/1 day

Specimen Retention Time

7 days

Reject Due To


Mild OK; Gross reject







Method Name

Spectrophotometry (SP)