Symptoms:

Symptoms of type 1 methemoglobinemia (erythrocyte reductase deficiency) include:

• Bluish coloring of the skin and mucous membranes

Symptoms of type 2 methemoglobinemia (generalized reductase deficiency) include:

• Developmental delay
• Failure to thrive
• Mental retardation
• Seizures

Symptoms of hemoglobin M disease include:

• Bluish coloring of the skin and mucous membranes
• Mild breakdown of red blood cells

Symptoms of acquired methemoglobinemia include:

• Bluish coloring of the skin and mucous membranes
• Headache
• Fatigue
• Shortness of breath
• Lack of energy

Signs and tests:

Methemoglobinemia can be diagnosed with a blood test.

A baby with this condition will have bluish skin color (cyanosis) at birth or shortly thereafter. Arterial blood gases and pulse oximetry results will be normal, making the condition challenging to diagnose.