PLATELET AGGREGATION: (089--0469)

Clinical Indication:

Differentiates platelet functional status and abnormalities, based on platelet responses to Arachidonic acid, ADP, Collagen, Epinephrin, and Ristocetin.

Test Mnemonic:

PLATAG

Methodology:

Photo Optical Detection

Performed:

Must be scheduled with Hematology Laboratory at 409-772-2293. Performed on Day Shift only, Monday through Friday.

Turnaround Time:

24 Hours.

Specimen Requirements:

Patient Preparation: Prior to drawing sample, patient must be fasting for eight (8) hours and must not have taken aspirin or medications containing aspirin within the previous 7-10 days (Contact lab for medication list).  Physician must provide a list of medications that have been taken.

Collect: Routine venipuncture; discard 1st mL of blood or collect other tubes ( red-topped) prior to collecting sample in 4 blue-topped (3.2% sodium-citrate) tubes  and one (1) purple topped tube. Immediately invert tubes gently at least 4 times to mix. Needle size should be between 19 and 21 gauge

Storage/Transport Temperature:   Specimen must be delivered to the lab within one (1) hour of collection, and is stable for 3-4 hours at room temperature.  The specimen should always be handled at room temperature (20-25°C) before testing and should never be refrigerated or chilled on ice or frozen.

Stability: Stable at room temperature for 3-4 hours.

Causes for Rejection: QNS, clotted, improperly collected samples, sample identification error, thrombocytopenia with platelets count < 100 x 10³/µl, severe hemolysis or lipemia, samples received in lab > 1 hours since collection.

Clinical Information:

If applicable, state clinical information that is required to be provided with specimen.

Reference Range:

Final Aggregation % is reported for each agonist tested.

ADP 20 uM:                    58 – 100%       

ADP 2 uM:                      9 – 100%

Collagen 190 ug/ml:      55 – 98%

Epinephrine 10 uM:       52 – 100%

Ristocetin 1.5 mg/ml:     55 – 99%

Ristocetin 0.5 mg/ml:      0 – 6%

Risotcetin 0.25 mg/ml:    0 – 4%

AD

Note:

CPT 4 Code:

 85576

Review:3/20/13 

W.Russo, MT(ASCP)

When ordering tests for which Medicare or Medicaid reimbursement will be sought, physicians should only order tests that are medically necessary for the diagnosis or treatment of the patient.  Components of the organ or disease panels may be ordered individually.  The diagnostic information must substantiate all tests ordered and must be in the form of an ICD-9 code or its verbal equivalent.