Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency

1. It is an enzyme that catalyzes the reaction to stabilize red blood cells and prevents them from being damaged.
2. G6PD deficient subjects normally enjoy good health, but they will develop acute hemolytic anemia when expose to exogenous stresses such as fava beans, certain drug or severe infections.
3. During acute hemolysis, hemoglobin metabolizes into bilirubin, which will cause jaundice.
4. Neonatal jaundice can be a serious problem if left untreated. Excess bilirubin can cause permanent brain damage and leading to neurological complications, which includes mental retardation, cerebral palsy and hearing deficit, or even death.
   
   

Etiology of G6PD Deficiency:

1. G6PD Deficiency is an X-linked recessive genetic condition, males are likely to be affected by this
2. Their parent may not be affected
3. Its ratio in Hong Kong is: there are 4 to 5 out of 100 male newborns and 3 to 5 out of 1,000 female newborns suffering from G6PD deficiency
4. G6PD Deficiency is an inheritable which is life-long condition, and there is no cure of the disease

Precaution for Acute Hemolysis affected:

1.  Avoid Chinese herbal medicines like:
   • Rhizoma Coptidis ( Huang Lian )
   • Calculus Bovis ( Niu Huang )
   • Flos Chimonanthi Praecocis ( Leh Mei Hua )
   • Margartias (Pearl Powder) etc. (e.g. Over-the-counter drugs such as Bo Ying Compund which contains Margartias)
2. Avoid Western medicines like:
   • Certain Antipyetics
   • Antibiotics: Nitrofurantoin, Nalidixic acid and Sulfamethoxazole
   • Antimalarials: Primaquine
   • Antispasmodics: Phenazopyridine
     (This list is not exhaustive. Please consult your doctor for more information)
3. Avoid eating fava or broad beans and their products (Pay attention to the food labelling).
4. Avoid close contact with mothballs (Naphthalene) and Naphthlene – containing products.
5. Inform doctor or medical staff about your status or show your G6PD deficiency document / alert card during consultation.
6. During hemolytic crisis, affected subjects will develop yellowish skin and mucosal membranes including the whites of the eyes. It may present as passing dark colored urine.
   • Neonates may refuse feeding, lacking energy and excessively sleepy
   • Children or adult may look pake, complain of tiredness, breathlessness and rapid hearbeats
7. Mothers who are breastfeeding their G6PD Deficiency babies should consult doctor before taking any Chinese or Western medicine.
8. Pregnant ladies should inform their medical and nursing staff about any family history of G6PD Deficiency.

Information retrieved from Genetic Screening Unit, Clinical Genetic, Department of Health

Version 2.0   Effective date: 6.2020