Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
Other disorders of blood and blood-forming organs
A condition in which a higher-than-normal amount of methemoglobin is found in the blood. Methemoglobin is a form of hemoglobin that cannot carry oxygen. In methemoglobinemia, tissues cannot get enough oxygen. Symptoms may include headache, dizziness, fatigue, shortness of breath, nausea, vomiting, rapid heartbeat, loss of muscle coordination, and blue-colored skin. Methemoglobinemia can be caused by injury or being exposed to certain drugs, chemicals, or foods. It can also be an inherited condition.
An inherited or acquired condition characterized by abnormally increased levels of methemoglobin in the blood. Signs and symptoms include cyanosis, dyspnea, headache, fatigue, mental status changes, and loss of consciousness.
The presence of methemoglobin in the blood, resulting in cyanosis. A small amount of methemoglobin is present in the blood normally, but injury or toxic agents convert a larger proportion of hemoglobin into methemoglobin, which does not function reversibly as an oxygen carrier. Methemoglobinemia may be due to a defect in the enzyme nadh methemoglobin reductase (an autosomal recessive trait) or to an abnormality in hemoglobin m (an autosomal dominant trait). (Dorland, 27th ed)