Vascular

One Liners

1. Quantification of hepatic copper content via a liver biopsy (>250 mu g/g dry weight) serves as the definitive gold standard and confirmatory diagnostic test for Wilson disease,
2. Most common inherited bleeding disorder = VwD

HEMODYNAMIC DYSFUNCTION

Hemorrhage

Hemorrhage is the escape of blood from the vascular system.

Types

Hemorrhage size

Clinical relevance: Petechiae may occur with platelet disorders, while deep tissue and joint hemorrhages are more characteristic of coagulation factor deficiencies.

Edema

Edema is abnormal accumulation of fluid in interstitial tissues or body cavities.

Mechanisms

Transudate versus exudate

Anasarca

Severe generalized edema involving widespread subcutaneous tissues.

Hyperemia and Congestion

Chronic passive congestion

Lung: Chronic pulmonary venous congestion may cause hemosiderin-laden macrophages, known as heart failure cells.

Liver: Chronic hepatic venous congestion may produce a nutmeg appearance due to centrilobular congestion.

MCQ tip: Nutmeg liver = chronic passive venous congestion.

Thrombosis

Thrombosis is the formation of a solid blood clot within the cardiovascular system during life.

Types of thrombi

Lines of Zahn

Alternating pale layers of platelets/fibrin and darker red cell-rich layers within a thrombus.

They support formation of the clot in flowing blood before death.

Fate of a thrombus

• Propagation.
• Embolization.
• Dissolution.
• Organization and recanalization.

Embolism

An embolus is a detached intravascular mass carried through blood to a distant site.

Types

Pulmonary thromboembolism

Usually arises from thrombi in deep veins of the lower limbs or pelvis.

Possible consequences:

• Asymptomatic small emboli.
• Acute respiratory distress.
• Pulmonary infarction in selected patients.
• Right ventricular strain.
• Sudden death from massive embolism.

Fat embolism syndrome

Classically associated with:

• Respiratory distress.
• Neurological abnormalities.
• Petechial rash.

Usually follows major skeletal trauma.

Amniotic fluid embolism

A rare, severe obstetric complication associated with sudden cardiopulmonary collapse and often coagulopathy/DIC.

Infarction

An infarct is an area of ischemic necrosis caused by impaired blood supply or venous drainage.

Red versus white infarcts

Remember: Brain infarction produces liquefactive necrosis.

Shock

Shock is systemic circulatory failure resulting in inadequate tissue perfusion and cellular oxygen delivery or utilization.

Types of shock

Stages of shock

Septic shock

Common mechanisms include:

• Dysregulated inflammatory responses.
• Vasodilation.
• Increased vascular permeability.
• Endothelial dysfunction.
• Microcirculatory abnormalities.
• Impaired cellular oxygen utilization.

MCQ tip: Early septic shock may produce warm, flushed skin because of peripheral vasodilation.

Disseminated Intravascular Coagulation (DIC)

DIC is systemic activation of coagulation, resulting in microvascular thrombosis and consumption of platelets and clotting factors.

Causes

• Sepsis.
• Major trauma.
• Obstetric complications.
• Certain malignancies.
• Severe systemic tissue injury.

Laboratory findings

Remember: DIC causes both thrombosis and bleeding.

Dual Circulation organs

Organs with dual blood supply or loose, spongy vascular networks (such as the lungs, liver, and gastrointestinal tract) are classic sites for red (hemorrhagic) infarctions.

When a vessel in a dual-supply organ becomes occluded, collateral blood flow from the secondary unobstructed vessel leaks into the ischemic, necrotic tissue, causing the infarcted area to fill with blood.

Erythrocyte Sedimentation Rate (ESR)

often referred to as a "sed rate"—is a common blood test that measures how quickly red blood cells (erythrocytes) settle at the bottom of a tall, thin, vertical test tube over the period of one hour (measured in mm/hr).

• Normal State: Under normal conditions, red blood cells carry a net negative charge (called a zeta potential) that causes them to repel each other and settle very slowly.
• Inflammatory State: During inflammation, infection, or tissue injury, liver-produced acute-phase proteins—primarily fibrinogen and globulins—increase in the plasma. These positively charged proteins neutralize the negative charge on RBCs, causing them to stack together like coins into clumps called rouleaux.
• Sedimentation: Heavier rouleaux overcome fluid resistance and sink to the bottom much faster, resulting in a higher ESR value.

Factors Affecting ESR

1. Factors that INCREASE ESR (Faster settling):

• Infections, Autoimmune Disorders, & Cancer: High fibrinogen/globulin levels speed up rouleaux formation.
• Anemia: Fewer RBCs relative to plasma allows cells to fall with less resistance.
• Old Age & Female Sex: Naturally tend to have slightly higher baseline ESR values.

2. Factors that DECREASE ESR (Slower settling):

• Increased Albumin: Albumin carries a strong negative charge that maintains RBC repulsion and inhibits rouleaux formation.
• Abnormal RBC Shapes: Sickle cell anemia, spherocytosis, or anisocytosis prevent proper rouleaux stacking, slowing down sedimentation.
• Polycythemia: A high density of RBCs creates "traffic jams" that hinder settling.

Coagulation profile

Platelet disorders

Platelet versus coagulation-factor bleeding

von Willebrand disease (vWD) is the most common inherited bleeding disorder. vWF mediates platelet adhesion and stabilises factor VIII, so vWD can impair both primary haemostasis and coagulation.

Important bleeding and clotting disorders

Liver disease and bleeding risk

The liver synthesises most coagulation factors, so hepatic dysfunction can affect both haemostasis and drug metabolism.

Dental considerations

• Review the severity of liver disease, platelet count, coagulation results, medication list and bleeding history before invasive procedures.
• INR alone does not fully represent bleeding risk in cirrhosis because procoagulant and anticoagulant proteins may both be reduced.
• Avoid automatically discontinuing medications or applying a single INR cut-off to every patient; decisions should be individualised with the treating team.
• Consider local haemostasis, appropriate analgesic selection and the potential for altered drug metabolism.

HEMOPHILIA A

Definition and Pathophysiology

Hemophilia A is an X-linked recessive bleeding disorder caused by deficiency or dysfunction of coagulation factor VIII. It impairs the intrinsic coagulation pathway and reduces stable fibrin clot formation.

Factor VIII acts as a cofactor for factor IXa in the intrinsic tenase complex, which activates factor X.

Clinical features

Severity classification

Severity is commonly classified according to residual factor VIII activity.

Common manifestations

• Hemarthrosis, particularly in knees, ankles and elbows.
• Deep muscle hematomas.
• Prolonged bleeding after trauma, surgery or dental extraction.
• Delayed or recurrent bleeding after procedures.
• Severe cases may develop intracranial or other life-threatening hemorrhage.

MCQ tip: Hemophilia A produces a prolonged aPTT with normal PT and platelet count.

Laboratory Findings

A mixing study typically corrects the prolonged aPTT when the cause is a factor deficiency. Failure to correct, or loss of correction after incubation, may suggest an inhibitor.

Dental Management of Hemophilia A

Dental procedures should be coordinated with the patient's hematology team.

Important precautions

• Obtain a bleeding history and current factor/inhibitor status.
• Assess the invasiveness of the planned procedure.
• Arrange factor VIII replacement or another appropriate hemostatic plan when indicated.
• Use local hemostatic measures, including sutures, pressure and suitable topical agents.
• Consider tranexamic acid when clinically appropriate.
• Avoid unnecessary trauma and use careful surgical technique.

Analgesic safety

Dental procedures and bleeding risk

• Simple examination and noninvasive treatment usually carry low bleeding risk.
• Local anesthetic techniques should be selected according to bleeding risk and the patient's hemostatic plan.
• Deep regional blocks, particularly inferior alveolar nerve blocks, may cause significant deep tissue hematoma if coagulation is inadequate.
• Extractions and periodontal surgery require an individualized plan, which may include factor replacement and antifibrinolytic therapy.

Clinical pearl: Do not treat all patients with hemophilia identically. Factor activity, inhibitor status, disease severity and the procedure determine the plan.

IDIOPATHIC THROMBOCYTOPENIC PURPURA (ITP)

Definition and Pathophysiology

Immune thrombocytopenia (ITP) is an acquired autoimmune disorder in which antibodies and immune mechanisms promote platelet destruction and may impair platelet production.

The result is a reduced platelet count and a tendency toward mucocutaneous bleeding.

Clinical features

Diagnosis

ITP is generally a diagnosis of exclusion. Assessment includes:

• Complete blood count and peripheral blood smear.
• Review of medications and possible secondary causes.
• Evaluation for other cytopenias or abnormal blood-film findings.
• Further investigations according to the clinical context.

Management

Treatment depends on platelet count, bleeding severity, comorbidities and the need for procedures.

Options may include:

• Observation in selected patients.
• Corticosteroids.
• Intravenous immunoglobulin (IVIG) when a rapid rise in platelet count is needed.
• Thrombopoietin-receptor agonists or other specialist therapies in persistent disease.
• Platelet transfusion in selected life-threatening bleeding situations, generally alongside treatments directed at immune-mediated destruction.

Platelet count and dental treatment

The PDF gives the following procedural guide. These values are educational thresholds, not universal clearance criteria; current recommendations vary by procedure and patient factors.

Local hemostatic measures

• Firm pressure and careful suturing.
• Absorbable hemostatic materials when appropriate.
• Topical tranexamic acid when indicated.
• Atraumatic technique and close postoperative follow-up.

Exam tip: ITP primarily causes mucocutaneous bleeding and thrombocytopenia. Hemophilia primarily causes deep tissue bleeding with a prolonged aPTT.

PLATELET DEFECTS VERSUS COAGULATION FACTOR DEFECTS

How to Differentiate Them

Primary versus secondary hemostasis

• Primary hemostasis: Platelets adhere, activate and aggregate to form an initial platelet plug.
• Secondary hemostasis: Coagulation factors generate thrombin and fibrin to stabilize the plug.

Remember: Mucosal bleeding suggests a platelet or von Willebrand disorder; hemarthrosis suggests a coagulation factor deficiency.

VON WILLEBRAND DISEASE (VWD)

Definition and Mechanism

Von Willebrand disease is a common inherited bleeding disorder caused by a quantitative or qualitative defect in von Willebrand factor (VWF).

VWF has two major functions:

1. Helps platelets adhere to damaged vascular endothelium.
2. Carries and stabilizes coagulation factor VIII in circulation.

Consequently, VWD can impair primary hemostasis and, in some forms, reduce factor VIII activity.

Clinical Features

• Easy bruising.
• Recurrent epistaxis.
• Gingival bleeding.
• Heavy menstrual bleeding.
• Prolonged bleeding after dental extraction.
• Postoperative mucosal bleeding.

Laboratory findings

VWD versus hemophilia A

Dental Management of VWD

The plan depends on subtype, bleeding history and procedure.

• Coordinate invasive treatment with hematology when necessary.
• Desmopressin may be useful in selected patients, depending on subtype and demonstrated response.
• VWF-containing concentrates may be needed for patients who do not respond to desmopressin or who require more substantial hemostatic support.
• Tranexamic acid and local hemostatic measures may be useful adjuncts.
• Avoid aspirin and generally avoid nonselective NSAIDs when bleeding risk is significant.

Important: Desmopressin is not appropriate for every VWD subtype. In particular, it is generally contraindicated in type 2B VWD because it can worsen thrombocytopenia.

OTHER CLOTTING DISORDERS

Hemophilia B — Christmas Disease

Hemophilia B is an X-linked disorder caused by factor IX deficiency.

MCQ tip: Christmas disease = factor IX deficiency.

Factor XI Deficiency — Hemophilia C

Factor XI deficiency is usually inherited in an autosomal pattern and has variable clinical severity.

• Bleeding is often most apparent after surgery or trauma.
• Bleeding risk is not reliably predicted by factor XI level alone.
• Spontaneous hemarthrosis is less typical than in severe hemophilia A/B.
• aPTT may be prolonged, while PT and platelet count are generally normal.
• Management is individualized according to bleeding history and procedural risk.

Disseminated Intravascular Coagulation (DIC)

DIC is systemic activation of coagulation, leading to widespread fibrin formation, microvascular thrombosis and consumption of platelets and clotting factors.

Causes

• Sepsis.
• Major trauma.
• Obstetric emergencies.
• Certain malignancies.
• Severe systemic tissue injury.

Laboratory pattern

Exam tip: DIC can cause simultaneous bleeding and thrombosis.

Intrinsic-pathway disorders — quick comparison

ANGINA BULLOSA HAEMORRHAGICA (ABH)

Definition

Angina bullosa haemorrhagica is a benign, usually self-limiting condition characterized by sudden blood-filled blisters in the oral mucosa, often following minor trauma.

Clinical features

• Sudden appearance of a blood-filled oral blister.
• Commonly affects the soft palate, although other oral sites may be involved.
• Often follows eating, chewing or minor mechanical trauma.
• The blister may rupture spontaneously, leaving a shallow ulcer.
• Usually heals without significant scarring.

Diagnosis and management

ABH is generally diagnosed clinically after excluding other causes of oral blood-filled lesions.

Management includes:

• Reassurance when the presentation is typical.
• Avoiding further trauma.
• Maintaining oral hygiene.
• Assessing the airway if a large posterior lesion causes swelling or obstruction.
• Investigating atypical, recurrent or unexplained lesions for thrombocytopenia, coagulation disorders or other mucosal diseases.

Exam tip: A sudden blood-filled blister on the soft palate after minor trauma, with otherwise normal hemostasis, suggests ABH.

ANEMIA

Definition and Hemoglobin Thresholds

Anemia is a reduction in hemoglobin concentration below the reference threshold for the relevant age, sex and physiological state, reducing the blood's oxygen-carrying capacity.

The PDF uses these commonly taught adult thresholds:

Pregnancy, altitude, age and the reference criteria used may alter interpretation.

Clinical Features

General manifestations

• Fatigue and weakness.
• Pallor.
• Dizziness or headache.
• Dyspnea on exertion.
• Tachycardia or palpitations in more severe cases.

Oral manifestations

Dental management

• Review recent CBC results and the cause/severity of anemia.
• Assess symptoms, exercise tolerance and relevant comorbidities.
• Elective invasive treatment may need to be postponed in patients with severe or symptomatic anemia.
• Use local anesthetics and other drugs according to the patient's overall medical status.
• Consider the underlying cause rather than treating the hemoglobin value in isolation.

The source's dental guidance flags hemoglobin below approximately 10 g/dL for increased concern with elective treatment. This is not a universal contraindication: urgency, symptoms, cause, cardiopulmonary status and the planned procedure must be considered.

CLASSIFICATION OF ANEMIA

Classification by Mean Corpuscular Volume (MCV)

MCV describes the average size of red blood cells and is a useful starting point for investigating anemia.

Iron Deficiency Anemia

Iron deficiency limits hemoglobin synthesis and commonly produces microcytic, hypochromic red blood cells as deficiency progresses.

Causes

• Chronic blood loss, including gastrointestinal or menstrual blood loss.
• Inadequate dietary iron.
• Increased requirements.
• Malabsorption.

Laboratory pattern

Oral manifestations

• Atrophic glossitis.
• Angular cheilitis.
• Oral mucosal pallor.
• In selected cases, association with dysphagia and esophageal webs in Plummer–Vinson syndrome.

Plummer–Vinson syndrome

The classic triad is:

1. Iron deficiency anemia.
2. Dysphagia.
3. Esophageal webs.

It is associated with increased risk of upper aerodigestive tract squamous cell carcinoma.

Megaloblastic Anemia

Megaloblastic anemia results from impaired DNA synthesis, producing abnormal maturation of hematopoietic cells.

The common nutritional causes are vitamin B12 and folate deficiency.

Vitamin B12 deficiency

Causes include:

• Pernicious anemia due to autoimmune intrinsic-factor deficiency.
• Gastric surgery or disorders affecting intrinsic factor.
• Terminal ileal disease or resection.
• Inadequate dietary intake, particularly over prolonged periods.
• Selected medications or malabsorption states.

Folate deficiency

Causes include:

• Poor dietary intake.
• Alcohol use.
• Increased physiological requirements.
• Malabsorption.
• Selected medications that interfere with folate metabolism.

B12 versus folate deficiency

Oral manifestations

• Atrophic glossitis.
• Smooth, red or painful tongue.
• Oral mucosal soreness.
• Angular cheilitis may coexist.

MCQ tip: Neurologic findings plus megaloblastic anemia strongly suggest B12 deficiency rather than isolated folate deficiency.

Normocytic Anemia

Normocytic anemia has an MCV within the usual reference interval, although the number of red cells or their hemoglobin content may still be reduced.

Causes

• Acute blood loss.
• Hemolysis.
• Chronic inflammation.
• Chronic kidney disease.
• Bone marrow suppression or infiltration.
• Early iron deficiency before microcytosis develops.

Initial investigation

The reticulocyte count helps distinguish whether the marrow is responding appropriately.

HEMOGLOBINOPATHIES

Sickle Cell Disease

Sickle cell disease is an inherited hemoglobin disorder caused by a β-globin mutation producing hemoglobin S (HbS).

When deoxygenated, HbS polymerizes, causing red blood cells to become rigid and sickle-shaped. These cells can hemolyze and obstruct small vessels.

Pathophysiology

HbS polymerization → red cell deformation → hemolysis + vaso-occlusion → anemia, ischemia and tissue injury.

Clinical manifestations

• Chronic hemolytic anemia.
• Painful vaso-occlusive crises.
• Acute chest syndrome.
• Increased risk of infection, especially from encapsulated organisms.
• Stroke and other ischemic complications.
• Renal, splenic and skeletal complications.

Oral and dental relevance

• Delayed eruption and other dental findings may occur, but are not diagnostic.
• Pulpal pain or ischemic complications can occasionally occur.
• Elective dental treatment should ideally be provided when the patient is clinically stable.
• Avoid dehydration, hypoxia, acidosis and poorly controlled pain or stress.
• Coordinate care for patients with severe disease or a history of major complications.

Exam tip: HbS polymerization is promoted by deoxygenation.

Thalassemia

Thalassemias are inherited disorders characterized by reduced or absent synthesis of α- or β-globin chains. The resulting globin-chain imbalance causes ineffective erythropoiesis and varying degrees of hemolysis.

Types

Clinical features

• Microcytic anemia.
• Variable hemolysis.
• Ineffective erythropoiesis.
• Hepatosplenomegaly in more severe forms.
• Skeletal changes from marrow expansion in transfusion-dependent disease.
• Iron overload, particularly with repeated transfusions.

Dental manifestations

Severe thalassemia may produce:

• Maxillary expansion.
• Prominent cheekbones.
• Facial skeletal changes.
• Malocclusion.
• Increased spacing or altered tooth position in some patients.

Dental management

• Assess current disease severity, transfusion history and iron-overload complications.
• Review relevant cardiac, hepatic and endocrine disease.
• Coordinate invasive procedures with the treating team when needed.
• Consider infection risk and medication-related issues in patients with significant comorbidities.

Remember: Both iron deficiency anemia and thalassemia can cause microcytosis. Ferritin and iron studies help distinguish iron deficiency from thalassemia.

HEMATOLOGICAL MALIGNANCIES

Leukemia

Leukemia is a malignant disorder involving hematopoietic cells, commonly affecting the bone marrow and circulating blood.

Classification

Acute versus chronic leukemia

Clinical manifestations

• Anemia causing fatigue and pallor.
• Thrombocytopenia causing bruising or bleeding.
• Neutropenia or dysfunctional leukocytes causing infection.
• Fever and weight loss.
• Lymphadenopathy or hepatosplenomegaly.
• Bone pain.

Oral manifestations

• Gingival enlargement, particularly in some AML subtypes such as monocytic/monoblastic leukemia.
• Spontaneous gingival bleeding.
• Petechiae and ecchymoses.
• Oral ulceration.
• Recurrent infection.
• Delayed healing.

Dental red flag: Unexplained gingival enlargement with spontaneous bleeding, pallor or recurrent infection warrants prompt medical investigation.

Lymphoma

Lymphomas are malignant proliferations of lymphocytes, usually presenting in lymph nodes or other lymphoid tissues, although extranodal disease can occur.

Hodgkin versus non-Hodgkin lymphoma

Common symptoms

• Painless lymph node enlargement.
• Fever.
• Night sweats.
• Unexplained weight loss.
• Fatigue and itching in some patients.

Dental relevance

• Some lymphomas involve the jaws, oral mucosa or salivary tissues.
• Unexplained persistent oral swelling or a rapidly enlarging mass requires assessment.
• Dental management depends on the diagnosis, stage, current therapy and risks of infection or bleeding.

Multiple Myeloma

Multiple myeloma is a malignant plasma-cell disorder associated with monoclonal immunoglobulin production and bone marrow involvement.

Key manifestations

The classic CRAB framework includes:

• C: Hypercalcemia.
• R: Renal impairment.
• A: Anemia.
• B: Bone lesions.

Oral and dental manifestations

• Jaw pain.
• Osteolytic lesions.
• Tooth mobility in affected regions.
• Pathological fractures.
• Delayed healing or infection risk, depending on disease and treatment.

Exam tip: Multiple punched-out lytic lesions of the skull are a classic radiographic association of multiple myeloma.