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Test ID: Hgb H
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Hemoglobin H Inclusion Bodies
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Useful For
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This test is useful in the diagnosis of alpha thalassemia intermedia (hemoglobin H disease).
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Method name and description
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Manual method using supravital stain.
Upon incubation with supravital stain (oxidant) such as Brilliant cresyl blue/new methylene blue, Hb H in the RBCs will be denatured and precipitate as small spherical inclusions evenly distributed giving the golf ball appearance.
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Reporting name
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Hemoglobin H Inclusion Bodies
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Clinical information
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Demonstrated by incubation of blood with supravital oxidizing stains (i.e:brilliant cresyl blue). Hemoglobin H is abnormal (unstable) Hb composed of excess of β chain (β chain tetramers) that forms due to reduced alpha chain synthesis (in alpha thalassemias). There are four types of alpha thalassemia corresponding to the number of alpha genes. Three gene deletion indicates HbH disease. Hb H disease can cause moderate to severe anemia and serious health problems such as an enlarged spleen, bone deformities, and fatigue. The signs and symptoms associated with Hb H disease vary widely. Some individuals are asymptomatic while others have severe anemia, requiring regular medical care. Hemoglobin H disease is found most often in individuals of Southeast Asian or Mediterranean descent.
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Specimen type / Specimen volume / Specimen container
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Whole blood.
Container/Tube: EDTA.
Specimen Volume: 3 ml (may be part of CBC)
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Collection instructions / Special Precautions / Timing of collection
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The test is performed when Hb result is ≤10.5g/dl for samples requested for Hemoglobin Electrophoresis.
Specimens must be analyzed within 48 hours of collection.
Do not centrifuge the specimen.
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Relevant clinical information to be provided
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Recent blood transfusion, patient/family history of alpha thalassemia
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Storage and transport instructions
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Ambient: 8 hours
Refrigerated: 48 hours.
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Specimen Rejection Criteria
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Insufficient quantity of blood (<1ml in macro tubes & <0.5ml in microtubes)
Errors in patient identification.
Delayed (old) specimen
Clotted specimen/hemolyzed sample
Wrong/unlabeled collection container
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Biological reference intervals and clinical decision values
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Factors affecting test performance and result interpretation
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Reticulocytes should be differentiated from cell with precipitated hemoglobin H. If blood and stain are not well mixed after incubation before preparing the smears.
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Turnaround time / Days and times test performed / Specimen retention time
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3 working days
Test is peformed daily
Specimen is retained for 3 Days at 2 - 8 °C
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