Glucose-6-phosphate dehydrogenase deficiency
Glucose-6-phosphate dehydrogenase deficiency
So what exactly is that?
Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive hereditary disease characterised by abnormally low levels of glucose-6-phosphate dehydrogenase (abbreviated G6PD or G6PDH), a metabolic enzyme involved in the pentose phosphate pathway, especially important in red blood cell metabolism. G6PD deficiency is the most common human enzyme defect.
In short,
Individuals with the disease may exhibit nonimmune hemolytic anemia in response to a number of causes, most commonly infection or exposure to certain medications or chemicals. It is closely linked to favism, a disorder characterized by a hemolytic reaction to consumption of broad beans, with a name derived from the Italian name of the broad bean (fava). The name favism is sometimes used to refer to the enzyme deficiency as a whole, although this is misleading as not all people with G6PD deficiency will manifest a physically observable reaction to consumption of broad beans.
So what is the signs??
Most individuals with G6PD deficiency are asymptomatic.
An asymptomatic carrier (healthy carrier or just carrier) is a person or other organism that has contracted an infectious disease, but who displays no symptoms. Although unaffected by the disease themselves, carriers can transmit it to others.
Symptomatic patients are almost exclusively male, due to the X-linked pattern of inheritance, but female carriers can be clinically affected due to unfavorable Lyonization, where random inactivation of an X-chromosome in certain cells creates a population of G6PD-deficient red blood cells coexisting with normal red cells. A typical female with one affected X chromosome will show the deficiency in approximately half of her red blood cells. However, in rare cases, including double X deficiency, the ratio can be much more than half, making the individual almost as sensitive as a male.
Abnormal red blood cell breakdown (hemolysis) in G6PD deficiency can manifest in a number of ways, including the following:
Prolonged neonatal jaundice, possibly leading to kernicterus (arguably the most serious complication of G6PD deficiency)
Hemolytic crises in response to:
1 Illness (especially infections)
2 Certain drugs (see below)
3 Certain foods, most notably broad beans
4 Certain chemicals
5 Diabetic ketoacidosis
6 Very severe crises can cause acute renal failure
This was the red blood cells if there is no diagnosis toward G6PD
This is another image of the signs getting G6PD
Favism may be formally defined as a haemolytic response to the consumption of broad beans. All individuals with favism show G6PD deficiency. However, not all individuals with G6PD deficiency show favism. For example, in a small study of 757 Saudi men, more than 42% showed a variant of G6PD deficiency, but none displayed symptoms of favism.[3] Favism is known to be more prevalent in infants and children, and G6PD genetic variant can influence chemical sensitivity.[citation needed] Other than this, the specifics of the chemical relationship between favism and G6PD are not well understood.
What are the causes??
Environmental triggers
Many substances are potentially harmful to people with G6PD deficiency, variation in response to these substance makes individual predictions difficult. Antimalarial drugs that can cause acute haemolysis in people with G6PD deficiency include primaquine, pamaquine and chloroquine. There is evidence that other antimalarials may also exacerbate G6PD deficiency, but only at higher doses. Sulfonamides (such as sulfanilamide, sulfamethoxazole and mafenide), thiazolesulfone, methylene blue and naphthalene should also be avoided by people with G6PD deficiency, as should certain analgesics (such as aspirin, phenazopyridine and acetanilide) and a few non-sulfa antibiotics (nalidixic acid, nitrofurantoin, isoniazid, dapsone, and furazolidone).
Another possible cause may because of
Genetics
All mutations that cause G6PD deficiency are found on the long arm of the X chromosome, on band Xq28. The G6PD gene spans some 18.5 kilobases.
So what exactly is that?
Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive hereditary disease characterised by abnormally low levels of glucose-6-phosphate dehydrogenase (abbreviated G6PD or G6PDH), a metabolic enzyme involved in the pentose phosphate pathway, especially important in red blood cell metabolism. G6PD deficiency is the most common human enzyme defect.
In short,
Individuals with the disease may exhibit nonimmune hemolytic anemia in response to a number of causes, most commonly infection or exposure to certain medications or chemicals. It is closely linked to favism, a disorder characterized by a hemolytic reaction to consumption of broad beans, with a name derived from the Italian name of the broad bean (fava). The name favism is sometimes used to refer to the enzyme deficiency as a whole, although this is misleading as not all people with G6PD deficiency will manifest a physically observable reaction to consumption of broad beans.
So what is the signs??
Most individuals with G6PD deficiency are asymptomatic.
An asymptomatic carrier (healthy carrier or just carrier) is a person or other organism that has contracted an infectious disease, but who displays no symptoms. Although unaffected by the disease themselves, carriers can transmit it to others.
Symptomatic patients are almost exclusively male, due to the X-linked pattern of inheritance, but female carriers can be clinically affected due to unfavorable Lyonization, where random inactivation of an X-chromosome in certain cells creates a population of G6PD-deficient red blood cells coexisting with normal red cells. A typical female with one affected X chromosome will show the deficiency in approximately half of her red blood cells. However, in rare cases, including double X deficiency, the ratio can be much more than half, making the individual almost as sensitive as a male.
Abnormal red blood cell breakdown (hemolysis) in G6PD deficiency can manifest in a number of ways, including the following:
Prolonged neonatal jaundice, possibly leading to kernicterus (arguably the most serious complication of G6PD deficiency)
Hemolytic crises in response to:
1 Illness (especially infections)
2 Certain drugs (see below)
3 Certain foods, most notably broad beans
4 Certain chemicals
5 Diabetic ketoacidosis
6 Very severe crises can cause acute renal failure
This was the red blood cells if there is no diagnosis toward G6PD
This is another image of the signs getting G6PD
Favism may be formally defined as a haemolytic response to the consumption of broad beans. All individuals with favism show G6PD deficiency. However, not all individuals with G6PD deficiency show favism. For example, in a small study of 757 Saudi men, more than 42% showed a variant of G6PD deficiency, but none displayed symptoms of favism.[3] Favism is known to be more prevalent in infants and children, and G6PD genetic variant can influence chemical sensitivity.[citation needed] Other than this, the specifics of the chemical relationship between favism and G6PD are not well understood.
What are the causes??
Environmental triggers
Many substances are potentially harmful to people with G6PD deficiency, variation in response to these substance makes individual predictions difficult. Antimalarial drugs that can cause acute haemolysis in people with G6PD deficiency include primaquine, pamaquine and chloroquine. There is evidence that other antimalarials may also exacerbate G6PD deficiency, but only at higher doses. Sulfonamides (such as sulfanilamide, sulfamethoxazole and mafenide), thiazolesulfone, methylene blue and naphthalene should also be avoided by people with G6PD deficiency, as should certain analgesics (such as aspirin, phenazopyridine and acetanilide) and a few non-sulfa antibiotics (nalidixic acid, nitrofurantoin, isoniazid, dapsone, and furazolidone).
Another possible cause may because of
Genetics
All mutations that cause G6PD deficiency are found on the long arm of the X chromosome, on band Xq28. The G6PD gene spans some 18.5 kilobases.
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