Platelet Disoders

Question 1

Typical clinical presentation of platelet disorders

Answer 1

Muco cutaneous bleeding
GI, GU, Oral bleeding
Epitaxial
Petechiae, purpura, bruising

Surgical or traumatic bleeding

Joint bleeding and non traumatic musculoskeletal bleeding is rare

Rarely intracranial bleeding ( in certain drugs )

Question 2

Thrombocytopenia causes ? ( 3 broad categories and specific causes )

Answer 2

Decreased production
– Drugs /Toxins
– Vitamin B12/folate deficiency
– Bone marrow failure –aplastic anaemia, myelofibrosis
– Bone marrow infiltration –leukaemia, metastases

• Increased destruction
– Immune thrombocytopenia (ITP)
– DIC/TTP
– Viral infections/Bacterial infections

• Sequestration
– Hypersplenism

Question 3

An ITP patient with a platelet count of 30k gonna have better haemostasis than an aplastic anaemia patient with same platelet count. Explain why

Answer 3

As the platelets are being destroyed in ITP there are always new platelets in the system. These new big platelets function better than mature platelets.

Question 4

What are some pathological mechanisms that cause primary ITP ?

Answer 4

Pathological antiplatelet antibodies
Impaired megakaryocytopoiesis
T-cell–mediated destruction of platelets

Therfore different patients will have different meds.

Question 5

What underlying disorders can cause secondary ITP ?

Answer 5

Autoimmune diseases ( SLE, Rheumatoid arthritis)
HIV
Helicobactor pylori
Immune dysregulation syndromes (CVID )