• Clinical science

Glucose-6-phosphate dehydrogenase deficiency (Favism)

Abstract

Glucose-6-phosphate dehydrogenase (G6PD) deficiency leads to an impaired regeneration of reduced glutathione, an important antioxidant, which makes RBCs more susceptible to oxidative stress and can result in episodic hemolytic anemia. The condition is inherited in an X-linked recessive pattern and is the most common human enzyme deficiency worldwide. It primarily affects males of African, Asian, and Mediterranean descent. G6PD is usually asymptomatic, but a sudden surge in oxidative stress (e.g., after infection, consumption of fava beans, or various drugs) may lead to a life-threatening hemolytic crisis. Diagnostic findings include signs of intravascular hemolysis (e.g., normocytic anemia, LDH, and haptoglobin), Heinz bodies, and bite cells on blood smear. Management mainly consists of preventing hemolysis by avoiding triggers.

Epidemiology

  • G6PD deficiency is the most common human enzyme deficiency.
  • Prevalence: ∼ 400 million worldwide
  • Affects primarily males of African, Mediterranean, and Asian descent

References:[1][2][3]

Epidemiological data refers to the US, unless otherwise specified.

Pathophysiology

References:[4][3][5]

Clinical features

  • Most patients are asymptomatic.
  • Recurring hemolytic crises may occur, especially following triggers
  • Recurrent severe infections causing symptoms of chronic granulomatous disease

References:[3][6][7]

Diagnostics

References:[1][8][3][6]

Treatment

References:[3][6]

Miscellaneous

Selective advantage in areas of endemic malaria: : As with sickle cell anemia, carriers of the G6PD deficiency may be less severely affected by malaria, especially disease caused by Plasmodium falciparum.
References:[9]

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last updated 10/16/2018
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