G6PD deficiency is the most common human enzymes deficiency results from mutation in the G6PD locus at Xq28. Inherited as an X-linked disorder, more prevalent among blacks. It confers protection against Malaria, which probably accounts for its high gene frequency.
The G6PD enzyme catalyzes the oxidation of glucose-6-phosphate to 6-phosphogluconate while concomitantly reducing the oxidized form of nicotinamine adenine dinucleotide phosphate (NADP+) to nicotinamine adenine dinucleotide phosphate (NADPH).
NADPH is necessary to keep glutathione reduced, which in turn detoxifies free radicals and peroxides. Decrease of NADPH in RBCs leads to hemolytic anemia due to poor RBCs defense against oxidizing agents.
The most common clinical feature of G6PD deficiency is lack of symptoms.
Symptomatic patients present with neonatal jaundice (this patient are placed under special lights –bili-lights- that alleviated jaundice), and acute hemolytic anemia.
Gallstones may be a prominent feature.
Splenomegaly may be present.
Acute hemolysis from G6PD deficiency is associated with the formation of Heinz bodies, which consist an altered hemoglobin precipitated within RBCs.
Medical Care:
Identification and discontinuation of the precipitating agents is critical in cases of G6PD deficiency.
Affected patient are treated with oxygen and bed rest.
Most individuals with G6PD deficiency do not need treatment.
Diet: avoid broad beans (fava beans).
Prevention:
.Avoid oxidant drugs such as the antimalarial drugs primaquine, chloroquine, pamaquine, and pentaquine.
.Avoid Nitrofurantion.
.Avoid nalidixic acid, ciprofloxacin niridazol, norfloxacin, methylene blue, chloranphenicol, phenazopyridine, and vitamin K analogues.
.Avoid sulfonamides.
.Avoid exposure to certain chemicals such as those in the mothballs.
.Other substances should be avoid:
-acetanili
-dexorubicin
-isobutyl nitrate
-naphthalene
-phenylhydrazine
pyridium
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