4.5 - G6PD Deficiency, Thalassemia, Aplastic & Myelophthisic Anemia

G6PD deficiency

G6PD is an enzyme involved in reducing oxidative stress on RBCs, producing reduced glutathione (GSH)

• X-linked hemolytic, normocytic anemia

  • clinical manifestations in males

• episodic hemolysis of RBCs following exposure to certain environmental antigens

  • drugs → aspirin, antimalarial drugs, sulfonamides, chloramphenicol, dapsone

  • infections

• hemolysis caused by production of denatured Hb that leads to:

  • increased hemolysis

  • formation of Heinz bodies

• dental management —

  • monitor for anemia/hemolysis, especially jaundice

  • avoid implicated medications

  • aggressively treat infections

  • follow guidelines in treatment for other non-sickle disease anemias

thalassemia

caused by mutation in alpha- or beta-globulin chains, resulting in decreased hemoglobin synthesis

• hemolytic, microcytic, hypochromic anemia

• autosomal dominant inheritance

• bone changes —

  • due to extra-medullary hematopoiesis

  • attempt to compensate for poor RBCs by making more

  • enlarged bones with decreased trabeculation

  • chipmunk facies → prominent zygoma/maxilla and flaring of maxillary anterior teeth

• radiographic findings —

  • stepladder trabeculations in the jaws

  • hair-on-end apperance of the skull

• dental management —

  • observe for hemolytic anemia signs, especially jaundice

  • aggressively treat infections

  • follow guidelines in treatment for other non-sickle disease anemias

aplastic anemia

bone marrow cannot adequately produce blood cells due to inability of hematopoietic stem cells to proliferate, differentiate, or generate mature blood cells

• may occur due to extrinsic factors (drugs) or immune-mediated suppression

• can cause pancytopenia due to loss of RBCs, WBCs, megakaryocyte/platelet production

• clinical features —

  • from anemia → fatigue, pallor

  • from thrombocytopenia → petechiae, ecchymoses, epistaxis, gingival bleeding

  • from leukopenia → infection

• refer if signs and symptoms present

• medical consultation required prior to dental treatment

myelophthisic anemia

infiltration of marrow by malignant neoplasm, most commonly a leukemia

• can cause pancytopenia due to loss of RBCs, WBCs, megakaryocyte/platelet production

• clinical features —

  • from anemia → fatigue, pallor

  • from thrombocytopenia → petechiae, ecchymoses, epistaxis, gingival bleeding

  • from leukopenia → infection

• refer if signs and symptoms present

• medical consultation required prior to dental treatment