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PA20.1-2 | Welcome to Platelet & Vascular Bleeding Disorders
Learning Objectives
- Distinguish primary haemostasis bleeding (mucocutaneous) from secondary haemostasis bleeding (deep/delayed) on clinical grounds.
- Classify thrombocytopenia by mechanism: decreased production, increased destruction, and dilutional causes.
- Explain the pathogenesis of Immune Thrombocytopenic Purpura (ITP) in its acute and chronic forms.
- Describe TTP/HUS and recognise its pentad and distinguishing laboratory features.
- Enumerate qualitative platelet defects and their molecular basis.
- List the major vascular purpuras and their clinicopathological features.
- Outline the laboratory approach to a patient with suspected platelet or vascular bleeding disorder.
INSTRUCTIONS
Bleeding disorders are divided into those affecting primary haemostasis (platelets + vessel wall) and those affecting secondary haemostasis (coagulation factors). Recognising the clinical pattern of bleeding is the single most powerful diagnostic step a clinician performs at the bedside — before any laboratory test. This module equips you to classify platelet and vascular causes systematically, understand their pathogenesis, and select the right investigations. These concepts are high-yield for both clinical exams and ward reasoning.
References
- Robbins & Kumar: Basic Pathology, 11th ed., Ch 12 (Red Cell and Bleeding Disorders) (textbook)
- Harsh Mohan: Textbook of Pathology, 8th ed., Ch 18 (Disorders of Platelet and Bleeding) (textbook)
Version 2.0 | NMC CBUC 2024