Question

Is the metabisulfite screen positive in sickle cell disease or trait?

1) Positive in sickle cell disease
2) Positive in sickle cell trait
3) Negative in both sickle cell disease and trait
4) Cannot be determined

Answer 1

The metabisulfite screen is positive for both sickle cell disease and sickle cell trait, as it reveals the presence of sickled hemoglobin (HbS), which is found in both conditions.

Step-by-step explanation:

The metabisulfite screen or test is used for the detection of sickle cell trait and sickle cell disease. This test causes deoxygenation of hemoglobin, which in turn can reveal the presence of hemoglobin S (HbS), found in sickle cell disease.

A positive metabisulfite screen indicates the presence of HbS. Therefore, the answer to the question is: 1) Positive in sickle cell disease and 2) Positive in sickle cell trait.

Individuals with sickle cell disease (homozygous for the sickle cell mutation, SS) have exclusively sickled red blood cells, while individuals with sickle cell trait (heterozygous, AS) have a mixture of normal and sickled cells.

Therefore, both sickle cell disease and sickle cell trait can give a positive metabisulfite screen result since both conditions involve the presence of HbS. It is relevant to note that individuals with sickle cell trait generally have fewer symptoms and may even exhibit a protective effect against malaria in endemic regions.