G6PD Deficiency
capable of producing the G6PD enzyme, resulting
is an important element (enzyme) in the glucose
in more severe symptoms. Females, on the other
oxidation (oxygen utilization) process of red blood
hand, inherit two X chromosomes, one from each
cells (RBCs) and for maintaining their normal life
parent. A mutation in one copy is compensated for
span. G6PD deficiency is an inherited disorder
by the presence of the other healthy copy of the
caused by a defect or deficiency in the production
gene. As a result, many females are carriers of the
of that enzyme. Consequently, G6PD deficiency
disease and do not present any clinical symptoms.
may cause the destruction of RBCs leading to a
However, in the rare case when a female receives
condition known as hemolytic anemia in which the
two defective G6PD genes, the hemolytic anemia
body cannot compensate for the destroyed cells.
becomes as severe as in the affected male.
In this condition, the patient may show jaundice
Interestingly, carrier females for G6PD deficiency
(pallor, yellowing of the skin, and discoloration of
are more resistant to malaria than normal non-
the eyes), dark urine, fatigue, shortness of breath,
carrier females and, hence, the high prevalence of
and a rapid heart rate. Many patients, however,
G6PD deficiency in areas that were, or still are,
remain without symptoms. Sometimes severe
hemolytic crisis in individuals with G6PD deficiency require immediate medical interventions. Environment: Hemolytic anemia associated with G6PD deficiency is usually triggered by bacterial
G6PD deficiency is the most common human blood
or viral infections as well as by certain drugs.
enzyme deficiency affecting about 400 million
Also, eating fava beans or inhaling pollen from
people worldwide. The highest prevalence rates
fava plants increase the breakdown of RBCs in
occur in areas where malaria is common, such as:
susceptible individuals, thus, leading to a condition
tropical Africa (20% of the population are affected),
the Mediterranean (4-30% are affected), tropical and subtropical Asia, and Papua New Guinea. However, the severity of the disease varies among
Diagnosis and Management
populations with the milder form being common in Africans, while the most severe form is found in
Some, but not all, newborns with G6PD deficiency
Mediterraneans and South East Asians.
are recognized because of jaundice occurring soon after birth. Among many affected males, the condition remains asymptomatic and the signs and
Risk Factors
symptoms of the disease may appear at any age only after the intake of fava beans or certain drugs. Genetic: Mutations in the G6PD gene, located on the X chromosome, are responsible for causing the
Hemolysis due to G6PD deficiency is best
disease by reducing the amount of G6PD enzyme
prevented by excluding fava beans from the
in the blood or altering its structure. Males inherit
diet as well as avoiding certain antibiotics (e.g.,
one X chromosome from the mother and one Y
Sulphonamides, Nitrofurantoin, Dapsone), anti-
chromosome from the father. Since the mutation
malarial drugs (e.g., Quinine, Chloroquine), anti-
affects the X chromosome, it cripples the only copy
cancer drugs, and other drugs such as Aspirin and
G6PD Deficiency
Hydralazine. In severe hemolysis, blood transfusion
males in Bahrain and Oman have this disorder. In
other Arab countries, G6PD deficiency occurs at relatively low to moderate rates: Jordan (3-12%), UAE (7.9%), Iraq (6.1%), Yemen (6%), Libya (2-3%),
G6PD deficiency in Arab Populations
Tunisia (1.84%), Lebanon (1.2%), and Egypt (1%).
G6PD deficiency is a common genetic disorder in
Genetic studies conducted in Algeria, Iraq, Kuwait,
almost all Arab countries due to the high frequency
and UAE have demonstrated that the Mediterranean
of the abnormal gene in conjunction with the high
type of G6PD deficiency occurs more commonly
consumption of fava beans in the region. The
in patients in the Arab World. In the UAE, 80% of
prevalence of the disorder varies widely in different parts of the Arab World. A very high frequency of
the G6PD deficient cases carry the Mediterranean
Hemophilia
G6PD deficiency has been recorded in Saudi Arabia
variant, which results in more severe symptoms than
among male and female newborns (37% and 21%,
other G6PD variants, due to an unstable enzyme and
respectively). Studies indicate that about 20-25% of
Sickle Cell Thalassemia ombophilia Thr
American Journal of Obstetrics and Gynecology (2004) 190, S30e8James Trussell, PhD,a,* Charlotte Ellertson, PhD,b Felicia Stewart, MD,cElizabeth G. Raymond, MD, MPH,d Tara Shochet, MPHeWoodrow Wilson School of Public and International Affairs, Office of Population Research, Princeton University,Princeton, NJa; Ibis Reproductive Health, Cambridge, Massb; University of California San Francisco,
IS 39 January 2011 Information sheet Anti-psychotic drugs: what to do if you are worried Background Sadly, this scenario is not uncommon, as we Alzheimer Scotland has been concerned for found at our 2010 Annual General Meeting some years about the extent of the use of experiences. It has also been recognised by the Scottish Government, which is committed to improving c