From the Guidelines
If you have giant platelets on your CBC, you should consult with a hematologist for further evaluation, as this finding may indicate an underlying blood disorder that requires specialized assessment, such as Bernard-Soulier syndrome, which is characterized by the presence of giant platelets and thrombocytopenia, as noted in a study published in the Journal of Thrombosis and Haemostasis 1. The next steps typically include additional blood tests, such as:
- A complete blood count with peripheral smear review to confirm the presence of giant platelets
- Platelet function tests, including flow cytometry screening using antibodies against GPIIb/IIIa (CD41), GPIIIa (CD61), GPIb (CD42b), and GPIb/IX (CD42a) to evaluate platelet function and identify potential defects, as recommended in a study published in the Journal of Thrombosis and Haemostasis 1
- Possibly genetic testing to identify underlying genetic mutations associated with inherited platelet disorders, such as MYH9-related disorders, which can cause giant platelets and other bleeding disorders, as noted in a study published in the Journal of Thrombosis and Haemostasis 1 Giant platelets can be associated with several conditions, including:
- Inherited platelet disorders, such as Bernard-Soulier syndrome, May-Hegglin anomaly, or other disorders, as listed in a study published in the Journal of Thrombosis and Haemostasis 1
- Certain inflammatory conditions, such as immune thrombocytopenia, which can cause giant platelets and thrombocytopenia, as noted in a study published in the Journal of Thrombosis and Haemostasis 1
- Reactions to medications, such as heparin-induced thrombocytopenia, which can cause giant platelets and thrombocytopenia, as noted in a study published in the Journal of Thrombosis and Haemostasis 1 While waiting for your hematology appointment, it is essential to:
- Continue taking any prescribed medications unless directed otherwise by your doctor
- Report any unusual bleeding or bruising promptly to your doctor, as giant platelets can increase the risk of bleeding complications, as noted in a study published in the Journal of Thrombosis and Haemostasis 1 The presence of giant platelets doesn't always indicate a serious condition, but proper diagnosis is crucial, as some associated disorders may require specific management to prevent bleeding complications, such as the use of platelet transfusions or fresh frozen plasma, as recommended in a study published in the Journal of Thrombosis and Haemostasis 1. Your hematologist will determine if you need any treatment based on your complete clinical picture, including your symptoms, other blood test results, and medical history, and will develop a personalized treatment plan to manage your condition and prevent bleeding complications, as noted in a study published in the Journal of Thrombosis and Haemostasis 1.
From the Research
Next Steps After CBC Shows Giant Platelets
The presence of giant platelets in a complete blood count (CBC) can be indicative of several conditions, including Bernard Soulier Syndrome, type 2B von Willebrand's disease, or other platelet disorders 2, 3.
- Platelet Function Tests: It is essential to conduct platelet function tests, such as platelet aggregometry, to assess the functionality of the platelets 2.
- Repeat Testing: Single atypically abnormal platelet aggregation studies should always be repeated to confirm the diagnosis, as initial results may not be accurate 2.
- Von Willebrand Disease Diagnosis: For patients suspected of having von Willebrand disease, high-resolution multimer analysis and the PFA-100 platelet function analyzer can be useful diagnostic tools, especially in cases where the ratio of ristocetin cofactor activity to von Willebrand factor antigen level is normal 4.
- Peripheral Blood Smear: A peripheral blood smear can help identify giant platelets and other abnormalities in blood cell morphology 3, 5.
- Manual Correction of CBC Results: In cases where giant platelets interfere with automated CBC results, manual correction using the traditional dilution method may be necessary to obtain accurate platelet and white blood cell counts 5.
Potential Conditions Associated with Giant Platelets
Giant platelets can be associated with various conditions, including: