Methemoglobinemia

This code represents a blood disorder characterized by the presence of an abnormally high level of methemoglobin in the red blood cells. Methemoglobin is a form of hemoglobin that cannot bind oxygen, leading to reduced oxygen delivery to tissues and potential cyanosis.

Use this code when documentation indicates a diagnosis of methemoglobinemia, whether congenital or acquired. This typically occurs due to exposure to certain drugs, chemicals, or genetic enzyme deficiencies. Supporting documentation should detail the diagnosis and, if known, the etiology.

• Differentiate between congenital and acquired forms if specified in the documentation, as some acquired forms may require additional external cause codes.
• Consider co-occurring conditions such as hypoxia or cyanosis, which may also require separate coding.
• Ensure documentation clearly states the diagnosis of methemoglobinemia, not just symptoms like cyanosis, to support this specific code.