ADENOSINE DEAMINASE
Adenosine Deaminase Deficiency (SCID)
BIOCHEMICAL ANALYSIS

Description:

Adenosine deaminase is deficient in one form of severe combined immune deficiency. The enzyme converts adenosine into inosine. This method measures the conversion of 14C-adenosine into inosine. The substrates and products of the reaction are separated by chromatography on a thin layer plate. The analysis of the products is somewhat complicated by the potential of conversion of the product, inosine, into hypoxanthine by purine nucleoside phosphorylase. This is particularly noticeable if large amounts of enzyme activity are present in extracts. Extracts should be diluted and re-assayed if this problem occurs.

Specimen Requirements:

The assay is routinely performed on red blood cells or white blood cells prepared from heparinized whole blood. Draw 3-5 ml in a yellow top (ACD) tube and ship to us on wet ice in an insulated container by overnight express. Sample must arrive at our location within 48 hrs. If the patient has been transfused, draw 7-10 ml in a yellow top (ACD) tube and ship to us on wet ice in an insulated container by overnight express. Sample must arrive at our location within 48 hrs. Cultured cells of all types can also be used. For fibroblasts, send two T25 flasks of confluent cells in an insulated container by overnight carrier. Contact the laboratory for information regarding prenatal diagnosis studies.

Normal Range:

Red Blood Cells: 0.42-4.50 µmoles/min/gm Hb
Skin Fibroblasts: 17-45 nmoles/min/mg protein
White Blood Cells: 8-20 nmoles/min/mg protein

Turnaround Time:

Amniotic Cell Culture, Cultured Chorionic Villus Cells: 3 weeks
Liver, White Blood Cells: 2 weeks
Skin fibroblasts assays are growth dependent

CPT Codes and Prices:

Amniotic Cell Culture: 82658x2, 82489x2, 88235x4, 88240x2, 84155x2, 83912x2, 83901x8, 83894x8, 83891x2
Cultured Chorionic Villus Cells: 82658x2, 82489x2, 88240x2, 88235x4, 84155x2, 83912x2, 83901x8, 83894x8, 83891x2
Red Blood Cells: 82489, 82658, 83026
Skin Fibroblast Culture: 82658, 82489, 88240, 88233, 84155
White Blood Cells: 82658, 84155, 82489

Shipping Information

Forms:

>> Biochemical Requisition
>> Biochemical Prenatal Consent
>> Prenatal Requisition

Test Codes:

Amniotic Cell Culture: 4507
Cultured Chorionic Villus Cells: 4508
Red Blood Cells: 4509
Skin Fibroblast Culture: 4510
White Blood Cells: 4511