Methemoglobinemia

On November 2, 2009, I began taking Dapsone, a medication to treat a lupus lesion on my face. Everything appeared to be on the mend until about 3 weeks later. I began feeling weak, tired, and dizzy. I figured I had a touch of the flu which was going around. I finally made a doctor's appointment when I no longer could get out of bed. I guess you could say, I hate going to the doctor almost as much as the dentist. By this time, my skin color was blue, from head to toe. I looked like something from the walking dead. As soon as my doctor saw me, I was rushed to the hospital, with an oxygen saturation level of 83%. Needless to say, I was in bad shape.

It was not long after arriving at the hospital that I was told that I had methemoglobinemia as a result of the Dapsone medication I had been taking. I was then nicknamed the "Smurf" and my nightmare was only about to begin.

 Methemoglobin is a form of hemoglobin that does not bind oxygen. Methemoglobinemia is when there are higher than normal levels of methemoglobin in a person's blood. Basically, the majority of  my red blood cells were not able to carry oxygen to my body. This is why I was blue- cyanotic. When the lab drew my blood, it was a chocolate brown color and my urine was maroon. I knew I was in trouble. Finally, on 15 liters of oxygen, my saturation level reached 90%. The Dapsone medication had literally crashed my hemoglobin.

There are different types of methemoglobinemia.

Congenital: A person can be born with methemoglobinemia, inherited from one or both parents with a recessive gene. If only one parent has the gene, the offspring will have normal color of skin. If both parents have the gene, the offspring will have a blue hue to the skin.

Methemoglobinemia can be caused by an enzyme diaphorase deficiency, resulting in higher levels of methemoglobin which inhibit's the red blood cells ability to carry oxygen.

It can also be caused by improper structure of the hemoglobin even though the enzyme system is intact.

Pyruvate kinase deficiency and G6PD deficiency can also cause methoglobinemia.

Acquired: Methemoglobinemia can be caused by medications, as was the case with me. Dapsone, benzocaine, and nitrates can cause the methemoglobin to rise in enormous numbers in the blood, compromising the oxygen carrying system. Certain Antibiotics such as trimethoprim, sulphonamides, and dapsone can be a causing factor as well. Local anaesthetics, such as articaine and prilocaine, have been known to cause methemoglobinemia. In addition, Aniline dyes, metoclopramide, bromates and chlorates are also been known to be culprits of causing this condition.

As soon as I was diagnosed with methoglobinemia, I began a series of methlyne blue treatments in addition to supplemental oxygen. The methlyne blue is taken IV and aids in restoring the hemoglobin to normal oxygen carrying state. This unfortunately was not the case for me. I continued to have rising levels of methemoglobin, despite the treatment and eventually started losing red blood cells. I was airlifted to a bigger hospital with poison control personnel on-site. There was a fear that I would require dialysis, in an effort to avoid my organs from shutting down due to insufficient oxygen levels. I was lucky in that none of this happened to me. After about a week, the Dapsone levels in my blood were gone, and I slowly began my healing. Fortunately, red blood cells regenerate every 120 days, the bad ones gone, with new healthy ones taking their place. I am still on oxygen, but am improving each day. By February, I should be able to supply oxygen on my own and return to a normal life.

All of this life-threatening drama happened because of a "sulfa allergy" that I have and have had all my life. Dapsone is contraindicated for those allergic to sulfa. Although this reaction that I had appears to be not the usual scenario, It almost cost me my life. It happened to me and I write this article in hopes that noone else experiences the methemoglobinemia nightmare.