Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency Flashcards
what is the most common disorder of red blood cell (RBC) metabolism?
glucose-6-phosphate dehydrogenase (G6PD) deficiency, a defect in the hexose monophosphate shunt pathway
where is the G6PD gene located, and why does it primarily affect males?
is located on the X chromosome, making males more likely to present with clinically significant hemolysis due to having only one X chromosome
why does G6PD deficiency make red blood cells (RBCs) more susceptible to damage?
G6PD deficiency renders RBCs susceptible to oxidative stress, which shortens RBC survival
what are common triggers of haemolysis in G6PD deficiency?
- fever
- acute viral/bacterial infection
- diabetic ketoacidosis
what substances can trigger hemolysis in G6PD deficiency by causing oxidative stress?
- rasburicase
- primaquine
- salicylates
- sulphonamides
- nitrofurans
- phenacetin
- naphthalene
- dapsone
- phenazopyridine
- nalidixic acid
- methylene blue
- fava beans
what are common symptoms of hemolysis in G6PD deficiency?
- transient jaundice
- dark urine
- back/abdominal pain
what can severe G6PD deficiency lead to during profound hemolysis?
- haemoglobinuria
- AKI
what two tests are used to diagnose G6PD deficiency?
- blood film
- G6PD enzyme assay
what are characteristic red blood cell (RBC) findings on a peripheral smear in G6PD deficiency?
- blister cells
- bite cells
- heinz bodies
why can G6PD activity testing give false-negative results during or right after a haemolytic episode?
- due to destruction of the older, more deficient RBCs and the production of reticulocytes, which are rich in G6PD
- testing may need to be repeated several weeks after the acute event
what is the management of G6PD deficiency?
- avoidance of triggers
- removal of offending medication or substance
- supportive
