Hemoglobin S and Hemoglobin F Quantitation for Therapeutic Monitoring, Blood
Monitoring patients with sickling disorders who have received hydroxyurea or transfusion therapy
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
The treatment of red blood cell sickling disorders may involve many therapeutic modalities. Two of the most important and beneficial are treatment with hydroxyurea and chronic transfusion therapy. Hydroxyurea causes elevation of hemoglobin F (Hb F) levels, and transfusion serves to lower the percentage of hemoglobin S (Hb S). Both of these therapeutic modalities act to lessen the number and severity of sickling crises. Thus, periodic monitoring of Hb F and Hb S levels are needed to guide further therapy.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
1-30 days: 22.8-92.0%
1-2 months: 7.6-89.8%
3-5 months: 1.6-42.2%
6-8 months: 0.0-16.7%
9-12 months: 0.0-10.5%
13-17 months: 0.0-7.9%
18-23 months: 0.0-6.3%
> or =24 months: 0.0-0.9%
All ages: 0.0%
Optimal levels of hemoglobin S and hemoglobin F are patient specific and depend on a number of factors including response to therapy.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This test is not intended for diagnostic purposes; thus, it is assumed the patient's diagnosis is established. If the patient has never been studied, hemoglobin electrophoresis is necessary (see HBELC/81626 Hemoglobin Electrophoresis Cascade, Blood).
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. The Management of Sickle Cell Disease. Fourth edition. Bethesda, MD: National Institutes of Health. National Heart, Lung, and Body Institute, 2002
2. Rosse WF, Telen M, Ware R: Transfusion Support for Patients with Sickle Cell Disease. Bethesda, MD: American Association of Blood Banks. 1998
3. Ferster A, Tahriri P, Vermylen C, et al: Five years of experience with hydroxyurea in children and young adults with sickle cell disease. Blood 2001;97:3268-3632
4. Charache S, Terrin ML, Moore RD, et al: Effect of hydroxyurea on the frequency of painful crises in sickle cell anemia. Investigators of the Multicenter Study of Hydroxyurea in Sickle Cell Anemia. N Engl J Med 1995;332:1317-1322