Oral Medicine: Red Cell Disorders

Oral Medicine, Diagnosis & Periodontology I

• Students are responsible for all material presented in lectures and sections, even if not in handouts.
• Textbook: Burket's Oral Medicine, 12th edition.

Red Cell Disorders

• Dr. Amira Abdelwhab
• RBC lifespan: 120 days.
• RBC count: 4.5-5 million/cubic mm (males); >females.
• Hemoglobin: 13-16 gm/dL (males); 13-14 gm/dL (females).
• Adult hemoglobin (Hb A): α2β2
• Fetal hemoglobin (Hb F): α2γ2

Classification of Red Blood Cell (RBC) Disorders

• Polycythemia
  • Absolute erythrocytosis: true increase in red cell mass
  • Relative erythrocytosis: red cell mass normal, but plasma volume reduced -Causes: intravascular fluid loss, rapid diuresis (secondary to congestive heart failure treatment) -Hemoglobin rarely rises >25% -No significant oral changes
• Anemia
  • Normocytic, normochromic
  • Microcytic, hypochromic (iron deficiency anemia)
  • Macrocytic, normochromic (pernicious anemia, folate deficiency)

Primary (Idiopathic) Polycythemia

• Etiology: unknown
• Age and gender: elderly (males > females).
• Characterized by:
  • High number of RBCs (up to 18 million/mm3).
  • High hemoglobin (18-24 g/dL).
  • Elevated white blood cell (WBC) count.
  • Elevated platelet count with dysfunction.
  • High blood viscosity.
  • Elevated serum iron and ferritin levels.

Secondary Polycythemia

• Etiology: varied causes (e.g., heart defects causing 2ry polycythemia, brain tumor)

Clinical Features of Polycythemia

• Symptoms/signs due to high blood volume and viscosity.
• Thrombosis as a complication of elevated blood viscosity
• Bone marrow overactivity

Extra-Oral Features of Polycythemia

• Purplish red face, extremities;
• Distended dark neck veins;
• Headaches;
• Bone Pain;
• Splenomegaly (enlarged spleen).

Oral Features of Polycythemia

• Purplish-red oral mucosa
• Varicosities in the ventral aspect of the tongue
• Bleeding gums
• Petechiae and ecchymoses

Dental Management of Polycythemia

• Particular attention to hemostasis during dental procedures.

Anemia

• Defined as a reduction in oxygen-carrying capacity of the blood, typically due to reduced numbers of red blood cells or decreased hemoglobin.
• Types of anemia:
  • Normocytic/normochromic anemia
  • Microcytic/hypochromic anemia (e.g., iron deficiency anemia)
  • Macrocytic/normochromic anemia (e.g., pernicious anemia, folate deficiency)

Iron Deficiency Anemia

• Etiology:
  • Inadequate iron intake
  • Impaired iron absorption (e.g., gastrectomy)
  • Chronic blood loss (e.g., heavy menstruation)
  • Increased iron requirements (e.g., pregnancy, growing children, or consumption of tea with meals)
• Clinical features:
  • Iron depletion
    • Sparse hair
    • Brittle nails
    • Spoon-shaped (koilonychia) nails
  • Anemia and tissue hypoxia
    • Fatigue
    • Headaches
    • Palpitations
    • Dyspnea on exertion
    • Pallor of skin, nail beds, and palpebral conjunctivae
    • Tachycardia
    • Cardiac murmurs
• Oral features:
  • Pallor of oral mucosa
  • Angular cheilitis
  • Glossitis
  • Sore mouth and atrophic oral mucosa
  • Slow wound healing

Plummer-Vinson Syndrome

• Smooth, red, painful tongue
• Atrophy of the mucosa of the mouth, pharynx; upper esophagus
• Angular cheilitis and oral ulcerations
• Dysphagia (difficulty swallowing)
• Mucosal atrophy due to iron deficiency

Pernicious Anemia

• An autoimmune disease where the stomach's parietal cells are progressively destroyed.
• Etiology:
  • Circulating autoantibodies.
  • Defective intrinsic factor secretion.
  • Defective vitamin B12 absorption.
• Defective RBC maturation
• Clinical features:
  • Insidious onset
  • Anemia
  • Severe pallor
  • Jaundice
  • Neurologic symptoms
  • Gastrointestinal symptoms (e.g., constipation, diarrhea, epigastric pain, increased risk of stomach cancer
• Oral features:
  • Glossitis, glossodynia (painful tongue), and sore atrophic tongue
  • Pallor of the entire oral mucous membrane
  • Aphthous-like ulcerations, particularly on the tongue
• Diagnosis:
  • Detailed history
  • Clinical examination
  • Laboratory investigation: decreased RBC count, reduced hemoglobin, increased MCV, MCH, reduced serum vitamin B12 testing
• Treatment:
  • Lifelong vitamin B12 injections

Folate Deficiency Anemia

• Macrocytic normochromic anemia due to folate deficiency
• Body reserve of folate in the liver can be depleted in less than 4 months.
• Causes:
  • Poor intake
  • Malabsorption
    • Inflammatory bowel disease
  • Increased demand
    • Infancy
    • Pregnancy
  • Drugs that interfere with folate absorption or metabolism
    • Alcohol
    • Barbiturates
    • Phenytoin
• Oral features(s) as with other types of anemia
• Diagnosis: Normal Schilling test, low serum folate level, normal serum vitamin B12 level.
• Treatment: Folic acid supplements (5 mg/day).

Aplastic Anemia

• Rare bone marrow aplasia
• Refractory normocytic normochromic anemia
• Leukopenia and thrombocytopenia (pancytopenia).
• Etiology: -Congenital causes (like Fanconi's anemia)
  • Acquired causes (immune suppression of bone marrow stem cells by T suppressor cells; drugs, e.g., cytotoxics like methotrexate, and noncytotoxics like chloramphenicol; radiation exposure; viral infections)
• Clinical features: Anemia, thrombocytopenia, and neutropenia are the principal clinical features. Frequent infections, bleeding, and fatigue are common. Oral manifestations include pallor of the oral mucosa, minimal or persistent gingival bleeding, petechiae and ecchymoses, and oral ulcers.
• Diagnosis: Detailed history and clinical examination; laboratory investigation for pancytopenia; normal MCV, MCH, and MCHC
• Treatment: Addressing the cause, bone marrow transplant is vital, sometimes.

Hemoglobinopathies

• Defects in the globin portion of the hemoglobin molecule; making RBCs with abnormal hemoglobin susceptible to hemolysis.
  • Sickle cell disease
  • Thalassemias
    • major
    • Minor

Sickle Cell Disease

• Hereditary disorder of hemolytic anemia
• Glutamic acid on beta chain is replaced by valine
• Clinical features:
  • Painful crisis - abdominal and bone pain due to blood vessel occlusion by sickled RBCs
  • Aplastic crisis - cessation of RBC production.
  • Splenic sequestration crisis - early childhood, spleen becomes enlarged as sickle cells entrap there, potentially fatal.

Sickle Cell Trait

• Heterozygous, mild form
• No significant clinical manifestations
• Increased risk in situations of hypoxia (e.g., general anesthesia)

Thalassemia

• Inherited group of anemias with deficient synthesis of either alpha or beta globin chains.
• Clinical features:
  • Slow growth & development of children.
  • Ashen gray skin color
  • Recurrent bacterial infections (increased iron availability).
  • Severe anemia (features of).
  • Hepatosplenomegaly
  • Skeletal growth retardation
  • Iron overload (due to repeated blood transfusions)
• Oral manifestation(s): Pale oral mucosa, Yelllowish tinge, delayed eruption and enamel hypoplasia, maxillary overgrowth, painful swelling of parotid glands caused by iron deposition, painful tongue, dentin and enamel with excessive quantity of iron (5 times normal).
• Radiologic features: similar to sickle cell anemia.

Diagnosis:

• Specific hematological finding(s) like reduced RBCs, reduced hemoglobin, reduced MCH, MCHC, MCV, elevated Fetal Hemoglobin
• Identifying factors like case history; clinical examination & laboratory investigation testing (including Schilling Test, Antibody for parietal cells, gastric intrinsic factors, Serum Folate).

Treatment:

• Eliminating causative factors/ addressing the underlying issue (like infection)
• Symptomatic treatment; supportive therapy like IV Fluids, oxygen, antibiotic and narcotic analgesics
• Medications like Folic acid (during pregnancy; severe hemolysis).
• Blood transfusions (as in aplastic crisis; reduced Hb levels)
• Bone marrow transplant

Dental implications of the above conditions:

• Avoid extensive soft tissue surgery due to slower healing time.
• Avoid general anesthesia if Hb is low.
• Treat any infections promptly.

This quiz covers material from the Oral Medicine, Diagnosis & Periodontology I course, focusing specifically on red cell disorders. Students will review key concepts related to red blood cell lifespan, classification, and abnormalities such as polycythemia and anemia, referencing Burket's Oral Medicine. Prepare to test your knowledge on the specifics of RBC disorders and their implications.