Haematology for Dental Students - Bleeding Disorders

Pathology of Bleeding Disorders:

Dr. Shashidhar Venkatesh MurthyA/Prof. & Head of Pathology

Learning Outcomes:

Discuss normal hemostasis, how bleeding stops.Discuss common bleeding disorders:

1. Common Blood Vessel disorders.

2. Common Platelet disorders.

3. Common Coagulation disorders.

4. Hypercoagulability/Thrombophilia disorders.

Discuss Pathology of each:• Clinical features, Pathogenesis & Laboratory diagnosis.

At the end of the session student will be able to,

Less More

Top Disorders:• Thrombocytopenia, ITP.• Vit-K deficiency.• Heparin, Warfarin, Aspirin• Cong: Haemophilia, VWD

Bleeding Disorders - Clinical

Normal Hemostasis Components:

1. BV – Vasoconstriction

2. Platelet plug formation

3. Activation of Coagulation – stable fibrin plug.

4. Activation of fibrinolysis – clot dissolution.

Injury

BV spasm

Plt. plug.

Coagulation

Fibrinolysis

Haemostasis overview:

BV Injury

PlateletAggregation

Blood Vessel Constriction

Coagulation Cascade

Stable Fibrin Plug

ReducedBlood flow

Plasma

Primary hemostatic plug

Blood Vessel

PlateletActivation

Fibrin formation*

Platelets

Injury

BV spasm

PLt. Act.

Coag.

FibrinolysisAnticoagulantsDisorders

ThrombophiliaDisorders Fibrinolysis

Disorders of Blood vessel Platelets Coagulation

LAB TEST:PT ~10 sec.Prothrombin Time. Factor 7

LAB TEST:aPTT ~20 sec.Activated Partial Thromboplastin Time.Factor 12, 9, 8

Bl. Clot

What actions are most excellent? To gladden the heart of a human being, to feed the hungry, to help the afflicted to lighten the sorrow of the sorrowful and to remove the wrongs of injured...” - Dr. APJ Abdul Kalam.

This is the reason medical profession is considered special…!

Clinical bleeding symptoms: Petechiae <3mm

Purpura <1 cm

Echymosis >1cm

Hematoma

Blood Vessel / Platelet disorder

Trauma / Coagulation

Key Words:• Hemostasis• Primary plug• Sec. / stable plug• Blood clot.• Plt. Aggregation.• Plt. Adhesion• Plt. Activation• Coagulation• Thrombosis• Thrombolysis• Thrombophilia

Superficial / Deep Bleeding

A. Superficial & small Platelet & BV disorderB. Deep & Big Coagulation disorder

Platelet / BV Coagulation

Good and Evil, happiness and misery, merit and sin depend on our actions. As is the action so is the result. It is easy & fun to indulge in sinful deeds but it is extremely painful to bear the bad results they yield.

Karma – You reap what You sow.. .

— Sai Baba

Bleeding Disorders: ClassificationPlatelet

AggregationBlood Vessel Constriction

Coagulation Cascade

Platelet Disorders:Function disorder

• Drugs – Aspirin• Kidney failure: uremia.

Thrombocytopenia:• Immune - ITP• Drugs, viral Infection• Aplastic anemia.• Chemotherapy.

Blood Vessel Disorders:Hereditary

• H.H.telangiectasia• Marfans sy.

Acquired• Simple easy bruising• Aging,Scurvy, • Drugs - steroids• Viral infections.

Coagulation Disorders:Hereditary:

• Haemophilia A, B• Von Willebrand’s

Acquired:• Liver disease.• Drugs - Heparin.• Inhibitors – immune.• Blood Transfusion

DIC – Disseminated Intravascular Coagulation All factor deficiency – Septicemia

“Thinking” should become your capital asset, no matter whatever ups and downs you come across in your life.” - Wings of Fire: An Autobiography of Dr. APJ Abdul Kalam.

Disorders of Haemostasis:

Blood vessel & Platelet disorders

Shashidhar Venkatesh Murthy B.Sc, MBBS, MD(path), GCTT, MBA(Edu), IFCAP(USA)

A/Prof. & Head of Pathology

Dengue – Hemorrhagic fever

Purpura in viral infections: Direct vascular damage, immune vasculitis leading to platelet activation & Coagulation.

BV & Plt

Spleen

Coag.

Bone Marrow Circulation

Thrombocytopenia: Commonest bleeding.Immune, Bone marrow dis, drugs, infections, Spleen

ITP: Immune Thrombocytopenic Purpura.

Autoimmune disorder. IgG Ab against plt. Mem. glycoproteins.

• Destroyed in Spleen. Thrombocytopenia, giant plts.• Insidius onset, Petechiae, purpura, easy bruising.

Acute & Chronic types.• Acute (children, post infections) • Chronic (females, 20-40y, Autoimmune)

Platelet counts & bone marrow examination.• BM: Increased Immature megakaryocytes.• Blood: Thrombocytopenia with giant platelets.• Other hemostasis tests normal.

Acute ITP: Petechiae

Chronic ITP: Female 28y.

Vit-K Deficiency: Green Veg & Intestinal bacteria. Deficiency of 2,7,9 & 10, C & S. Diet, Drugs & Liver Disease Warfarin * Lab: PT. Normal PTT (F7)

Warfarin

Factors: 2,7,9,10

Von Willebrand Disease:• Commonest Cong. Bl. Disorder.

• Autosomal recessive (M:F)

• Deficiency of vWF & F VIII*

• Both Plt & Coag. Disorder.• Type-1 85%, Quantitative, mild.

• Type 2 – Qualitative, rare.

• Type 3 – total absence, rare.

• Easy bruising & muco-cutaneous bleeding. Petechiae, Purpura.

• Lab Diagnosis:

• Prolonged bleeding time & normal coagulation time (mild F8 def.).

• Normal platelet count.

Plt & F VIII

Haemophilia-A X linked. Xq 2.8, Factor VIII def. Males affected, Female carrier. Factor level of >30% normal. Factor level <1%, 1-5%, >5% mild Wound bleeding & Hematoma. aPTT prolonged PT normal,

FVIII assay. Treat: FVIII. Haemophilia B: similar, F IX def.

Mild >5%

Mod 1-5%

Severe <1%

Chronic deformity

DIC: Disseminated Intravascular Coagulation.

Excess whole body activation of hemostasis Consumption of factors Bleeding.

Cause / Etiology: (infection, trauma, cancer)• Tissue factor release into circulation - trauma• Or Widespread endothelial damage - infection

Morphology / Clinical features:• Thrombosis, Severe bleeding, shock, renal failure.

Laboratory Diagnosis:• All tests abnormal*

“To educate a person in the mind but not in morals is to educate a menace to society.”

-Theodore Roosevelt

Anticoagulants & Hypercoagulability Disorders.

Heparin

WarfarinWarfarin

Bl. Clot

Thrombophilic disorders:

Hereditary:• Factor V Leiden (resistant to breakdown)• Protein C or S deficiency (anticoag.).• Prothrombin Gene mutation (hyperact.)

Acquired:• CVS disorders – MI, DM, HPTN.• Major trauma or inflammation or

malignancy – procoagulants.• Drugs - Oestrogen therapy.• Hyperhomocyteinaemia (rarely hereditary)• Antiphospholipid syndrome.

• Lupus anticoagulant & Anti cardiolipin Ab.

• Arterial thrombosis• Thromboembolism• Venous thrombosis• Abortions.

“Intelligence plus character, that is the goal of true education”

- Martin Luther King Jr.

Students today enticed by modernity, have become oblivious to their

identity & purpose in life.

“In order to succeed, your desire for success should be greater than your fear of failure.”

- Bill Cosby

“To educate a person in the mind but not in morals is to educate a menace to society.”

-Theodore Roosevelt

What you admire in others will develop in yourself. Therefore, to love the ordinary in any one is to become ordinary, while to love the noble and the lofty in all is to

grow into the likeness of that which is noble and lofty.

— Christian Larson

Why only PT abnormal in Vit-K def?

Ans: Shortest half life…!

Why no effect?

Vit-K Liver Coag. Factors 2,7,9,10 – both PT & aPTT should raise…?