Methaemoglobinaemia
Methaemoglobinaemia Causes
Methaemoglobinaemia is caused by elevated levels of a type of hemoglobin called methemoglobin in blood. It may come in one of two forms: congenital methaemoglobinaemia and acquired methaemoglobinaemia. Congenital methaemoglobinaemia results from an inborn deficiency of the enzyme diaphorase; while acquired methaemoglobinaemia results from exposure to exogenous oxidizing drugs and their metabolites, which accelerates the rate with which methemoglobin forms in the blood.
Methaemoglobinaemia Definition
Methaemoglobinaemia pertains to a disorder marked by the presence of abnormally high levels of methemoglobin (a type of hemoglobin that doesn't bind oxygen) in the blood, possibly leading to anemia and tissue hypoxia. Methaemoglobinaemia is also sometimes referred to as met-Hb.
Methaemoglobinaemia Diagnosis
Blood tests can reveal elevated methemoglobin levels in blood.
Methaemoglobinaemia Symptoms and Signs
Methaemoglobinaemia may present with the following symptoms: cyanosis; shortness of breath; changes in alertness and general mental status; headaches; fatigue; exercise intolerance; dizziness; and loss of consciousness. In severe cases, affected patients may develop: seizures, coma, dysrhythmias, and even death. When the concentration of methemoglobin is high in red blood cells, some of the possible complications are anemia and tissue hypoxia.
Methaemoglobinaemia Treatment
Patients with methaemoglobinaemia are treated with intravenous supplemental oxygen and methylene blue solution, which restores iron hemoglobin to its normal oxygen-carrying state.