G6PD Deficiency Flashcards
What is G6PD deficiency?
Glucose-6-phosphate dehydrogenase is an enzyme involved in hexose monophosphate pathway. It facilitates part of the pathway which provides protection of red blood cells against oxidant threats. In a state of reduced activity, red cells are at greater risk of oxidate haemolysis leading to precipitation of haemoglobin (Heinz bodies) or red cell membrane damage.
Reference: Nelson’s Paediatrics [20th Edition], p.2355; Starship Clinical Guidelines.
What causes G6PD deficiency?
G6PD deficiency is an genetic disorder showing an X-linked inheritance pattern.
It is more common in Mediterranean, African-American, Middle Eastern and Asian ethnic groups.
Reference: Nelson’s Paediatrics [20th Edition], p. 2355.
How does G6PD deficiency present?
Symptoms generally manifest themselves within 24-48 hours of exposure to the trigger:
Acute haemolysis
Caused by exposure to some medications, infections, foods, etc.
Chronic haemolysis
More rare
Anaemia
Pallor, tiredness
Jaundice
Dark Urine
Haemoglobinuria
Back Pain
Reference: Starship Clinical Guidelines
What are the triggers in G6PD deficiency?
Medications
Antibiotics
Sulfonamides, Co-trimoxazole, Chloramphenicol, Nitrofurantoin
Antimalarials
Primaquine, Chloroquine
Others
Methylene Blue, Probenecid, Rasburicase
Chemicals
Benzene, Moth Balls (Naphthalene)
Illness
DKA, Sepsis, Hepatitis
Reference: Nelson’s Paediatrics [20th Edition], p.2356.
How is G6PD deficiency investigated?
Full Blood Count
Reticulocyte Count
Blood Film
May see Heinz bodies (precipitated Haemoglobin)
G6PD Activity
<10%
Reference: Nelson’s Paediatrics [20th Edition], p. 2356; Starship Clinical Guidelines
How is G6PD deficiency managed?
Remove the responsible trigger
Avoid exposure to triggers
Blood transfusions may be required
Recovery within about a week is the norm
Reference: Nelson’s Paediatrics [20th Edition], p. 2356-2357; Starship Clinical Guidelines.
