Lab Test

Platelet Aggregation (Southeast Michigan Only)

Platelet Function Studies, Ristocetin Aggregation, RIPA Study

Test Codes

EPIC: LAB1231133

Department

Coagulation

Instructions

  • Inpatient (Royal Oak Only): Specimens should not be collected before 7:00 am and must be received before 12:00 pm, Monday – Friday only. This test is not available to inpatients at the other Beaumont Hospitals. 
  • Outreach, and all other Beaumont site specimens cannot be accepted. The patient must have a Royal Oak outpatient visit created and have their blood drawn at Royal Oak at the Rose Cancer Center
  • Outpatients, other Beaumont sites patients, and Outreach patients must schedule appointments through the appointment center, 248-577-9700.
  • Do not eat, drink (except water), smoke, or exercise the morning of your appointment. Do not drink alcohol the day before or the day of your appointment.
  • If you are taking aspirin, clopidogrel (Plavix), or ticlopidine (Ticlid) you must contact your physician. Your physician may require that you discontinue these medications 14 days prior to your appointment. However, if your physician is testing your blood to determine if the medications are working, he/she may want you to continue taking them.
  • Continue taking all other prescribed medications as normal.
  • Please bring a list of all the medications that you have taken within the last seven days including herbals, over-the-counter medications, and prescription medications.

  • You must bring your physician's written order with you to your appointment. Without it, we may be forced to reschedule your exam.

Specimen Collection Criteria

Collect: Eight Light Blue-top 3.2% Sodium Citrate tubes.

  • ALL TUBES MUST BE FULL.
  • Tubes must be HAND-DELIVERED to the Coagulation Laboratory immediately. Do NOT send through the pneumatic tube system.
  • For Outpatient specimens, a copy of the requisition with a sign, symptom, or diagnosis must be faxed to the Hematology laboratory at 248-551-5372.

Rejection Criteria

  • Specimens sent through the pneumatic tube system.
  • Glass tubes and 3.8% Sodium Citrate tubes.
  • Specimens that are clotted or grossly hemolyzed.
  • Inappropriate specimen volumes. Testing must be completed within 4 hours from time of collection.
  • The Laboratory will cancel the test if unable to obtain platelet rich plasma with adequate platelet count.

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 3 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

Room Temperature (20-26°C or 68-78.8°F): 1 day

Laboratory

Royal Oak Coagulation Laboratory

Performed

Inpatients (Royal Oak Only): Monday – Friday*, 9:00 am – 12:00 pm.
Outpatients: Performed by scheduled appointment only, Monday – Friday, 8:30 am or 10:30 am. Results available within 2 business days.

*NOTE: This test will not be performed on holidays. 

Reference Range

ADP 10 mcM Max & Rate: Greater than or equal to 65%.
ADP 5 mcM Max & Rate: Greater than or equal to 60%.
Ristocetin 1.5 mg/mL Max & Rate: Greater than or equal to 70%.
Ristocetin 1.0 mg/mL Max & Rate: Greater than or equal to 65%.
Ristocetin 0.5 mg/mL Max: Less than or equal to 15%.
Collagen 2.2 mcg/mL: Greater than or equal to 65%.
Collagen Lag Phase (Seconds): Less than or equal to 70.
Arachidonic Acid 500 ug/mL: Greater than or equal to 60%.

Test Methodology

Aggregation, Optical PRP.

Interpretation

An interpretive Pathologist's report is included with results.

Clinical Utility

This assay aids in the evaluation of platelet function, the diagnosis of von Willebrand disease, Glanzmann's disease, storage pool disease, Bernard-Soulier syndrome, and other intrinsic platelet disorders.

CPT Codes

Per agonist: 85576 X7

Interpretation: 85576-26

Contacts

Last Updated

11/12/2024

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