Haematology Flashcards
- Severe nose bleeds and post-surgery bleeding (predominantly mucosal bleeding)
- Autosomal dominant inheritance
- Mildly elevated APTT
What is the provisional diagnosis and what test would confirm this??
Mild type 1 vWF deficiency
Confirm via blood tests for:
vWF Ag levels
vWF activity or function tests
- X-linked inheritance
- Characterised by joint bleeding! (often post-trauma)
- Mildly elevated APTT
What is the provisional diagnosis and what test would confirm this?
Mild Type Haemophilia
Confirm via blood tests for factors 8 (deficiency=Type A) and 9 (deficiency=Type B)
And/or genetic tests
- Bruising and petechiae on skin +/- Blood blisters on palate/mucosal surfaces, epistaxis, menorrhagia, GI bleeding, intracranial bleeding…
- Previously well with no medications
- Only abnormality on investigation is thrombocytopenia
What is the provisional diagnosis?
Treatment for this?
Immune Thrombocytopenia Purpura (ITP)
Diagnosis of exclusion!
Make sure to do FBE, blood film, U&Es, LFTs (can lead to renal failure), ANA, serology for EBV & CMV
Treatment:
- High dose steroids
- IV Ig if bleeding
- Splenectomy if life-threatening bleeding
- DO NOT give plts
- Arterial or venous blood clots
- Mixing study not correctable - what does this mean and what further bloods would you order for diagnosis?
What is the provisional diagnosis ?
indicating presence of an inhibitor rather than factor deficiency
-Blood tests positive for anticardiolipin and antiphospholipid Ab
Antiphospholipid syndrome (primary or secondary to SLE or induced by drugs such as Quinine)
- HX severe trauma, obstetric complications, sepsis, allergic/toxic reaction, cancer
- Investigations reveal: Low Hb and Plt; high APTT and PT; low fibrinogen; positive D dimer
What is the provisional diagnosis ? What is the underlying pathophys?
Disseminated Intravascular Coagulation
Widespread activation of clotting cascade results in formation of clots in microvasculature around body, leading to organ infarct and coagulation factor deficiency which leads to bleeding at other sites.
Causes microcytic anaemia
Iron deficiency (slow chronic bleed or nutrient deficiency)
Anaemia of chronic disease
Thalassaemia
Causes normocytic anaemic
Hypoproliferative
- leukaemia
- aplastic anaemia
- pure red cell aplasia
Hyperproliferative
- haemmhorage/bleed
- haemolytic anaemia (sickle cell, thalassaemia, spherocytosis, G6DP deficiency, haemolytic uraemia, DIC, TTP)
Causes macrocytic anaemia
Megaloblastic
-B12/folate deficiency
Non-megaloblastic
- cirrhosis, liver failure
- alcoholism
- myelodysplastic syndrome
- congenital bone marrow failure syndrome
- myeloproliferative disorders
- myeloma
What are 2 common causes of acute decline in CML?
Developing Largre B Cell lymphoma
Infection from immunocompromised state (few white cells)
Casues of mediastinal obstruction
- Massive lymphadenopathy
- Thyroid (neoplasm or goitre)
- Thymus (neoplasm)
- Teratoma (germ cell neoplasm)
- Terrible lymphoma (lymphoma or lymphoblastic)
What is the name of the cells characteristically found on Hodgkins lymphoma histopath?
Reed Sternberg cells.
35 year old female w erythema nodosum, SOB (CT chest shows pulmonary nodules)
What are 2 probable diagnoses and what histo path pattern would you see on biopsy?
Sarcoidosis or Tb.
Granulomatous inflammation on biopsy.
Pathophys of ITP
Patient develops autoantibodies for glycoprotines (Ag) on platelet membranes -> platelets targeted to the spleen for sequestration -> destroyed (phagocytosed) by mononuclear macrophages
Signs and symptoms of ITP
Petechiae and ecchymoses
Gingival bleeding
Haemorrhagic bullae
Occurs in otherwise healthy person (no splenomegaly, wasting, signs of chronic disease/infx)
MX ITP
Prednisone + IV Ig
DO NOT infuse platelets - they will be destroyed by immune response!
DDX for petechiae/purpura/ecchymosis
- Thrombocytopenia
- ITP
- Secondary to meds, leukaemia, SLE, APL syndrome, vWF deficiency - Vascular disorders
- Senile purpura, HTN, Henoch Schonlein purpura - Coagulation problem
- DIC or Scurvey - MENINGOCCOCEMIA
Extrinsic pathway:
- which blood test measures this?
- what drug acts on this pathway?
- INR /PT
2. Warfarin
Intrinsic pathway:
- which blood test measures this?
- what drug acts on this pathway?
- APTT
2. Heparin
What is primary haemostasis?
How do you test this?
Vasoconstriction, platelet adhesion and activation via binding vWF, and pletelet aggregation to form plug.
Triggered by exposure of collagen and subendothelial matrix from vessel injury
Test via platelet count.
WHat is secondary haemostasis and how do you test it?
Reinforcement of platelet plug by formation of fibrin meshwork via extrinsic and intrinsic pathways.
How does the extrinsic pathway differ from intrinsic pathway in how they start, and where do yhey join up with the common pathway?
Extrinsic: starts w tissue damage & exposure of Tissue factor
Intrinsic: starts with conversion of factor 12 to 12a
Common pathway: conversion of factor 10 to factor 10a
How long does clopidogrel stay in system for?
10-12 days. essentially a long-acting aspirin
What can you do for bleeding due to drugs?
- dabigatran
- warfarin
- clopidogrel/aspirin
- prothrombinex and activated factor 7
+ antidote for dabigatran - give vitamin K, Or FFP and prothrombinex
- Give platelet transfusion (aspirin and clopidogrel affect platelets for extent of life span) and FFP
Differentials for abnormal bleeding
Haemophilia A or B vWF disorder Other factor deficiency Platelet disorder Anticoag/antiplatelet drugs
Investigations to order for bleeding disorders
FBE - plts, Hb
Coags
Factor VIII, IX levels (factor 8 levels give indicator of vWF levels; haemophilia A and B)
vWF Ag
vWF activity or function test
Blood group (group 0 have lower levels vWF)
Genetic studies
Type 1 vs Type 2 vWF deficiency
type 1- partial deficiency
type 2-complete vWF deficiency
Treatment for vWF disease
Treat only if symptomatic
Desmopressin - releases stores of vWF and factor 8
OR replacement therapy (recombinant factor 8/vWFAg concentrate or recombinant vWF Ag or cryoprecipitate)
Antifibrinolytics to symptomatically treat tranexamic acid
What are the hallmarks of haemophilia?
X linked (in males)
Haemarthrosis
Subcutaneous and intramuscular haematomas
Poor wound healing
Abnormal APTT but normal INR (factor 8 and 9 only involved in intrinsic pathway)
Treatment of haemophhilia
Replace factor 8 or 9