Understanding key terminology helps me fight PNH, aplastic anemia

Gaining knowledge about my blood disorders has been empowering

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by Brandi Lewis |

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Have you ever paused during an appointment because your doctor used a term you didn’t understand? When it happened to me, it was like time had stopped. I was no longer listening to my doctor; instead, my mind filled with questions as I tried to figure out what the term meant.

When you have a chronic or rare illness, one important lesson you learn is how to adapt and understand the key terminology that comes with your diagnosis.

After being thrust into the world of aplastic anemia and paroxysmal nocturnal hemoglobinuria (PNH), I began to recognize the weight of such words. This was one of many times when Google searches were my best friend.

Following my diagnosis, I met with my doctor to establish an action plan for fighting two blood disorders. Because few providers in the U.S. are familiar with my conditions, my doctor and I were tasked with learning more about them.

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My doctor walked into the follow-up appointment with persistence and confidence. She said she’d been researching my illnesses and learning more about PNH. I could tell she wanted to calm my nerves with the research she’d done to make the process easier for me.

She began to explain her findings, but all I remember from that conversation were terms like “flow cytometry test.” That’s when my curiosity peaked. She went on to mention clone size and hemoglobin levels, then followed up with a discussion about platelets, red blood cell count, and complete blood count. Once I began to understand this key terminology, that knowledge helped immensely in my battle against PNH and aplastic anemia.

Following are five of the most important terms that I believe PNH patients should understand, based on my experience:

1. Flow cytometry test

As PNH News notes on its diagnosis resource page, a flow cytometry test is considered the gold standard for diagnosing PNH. It measures the level of specific proteins that help prevent the destruction of red blood cells and other functions. These levels “are either low or undetectable in people with PNH.”

2. PNH clone size

PNH clone cells are blood cells that have been affected by PNH. “The PNH clone size refers to the proportion of PNH-affected cells versus normal cells within the total cell population,” the European Society for Blood and Marrow Transplantation notes in a guide to understanding PNH. This number can vary greatly among PNH patients and may even change over time for individuals.

3. PNH

We know what PNH stands for, but it’s crucial to understand each word. “Paroxysmal” means sudden, recurrent attacks or increasing symptoms. “Nocturnal” refers to nighttime. “Hemoglobinuria” means hemoglobin in the urine.

But, as PNH News notes, “the term nocturnal in the name PNH can be misleading, given that the destruction of blood cells that causes disease symptoms can happen continually throughout the day. However, the reddish discoloration associated with hemoglobinuria is often seen most clearly in the morning.”

4. Bone marrow failure

PNH and aplastic anemia are both bone marrow failure diseases. According to the Aplastic Anemia and MDS International Foundation, “Bone marrow failure happens when the marrow does not produce enough red cells, white cells, or platelets, or the blood cells that are produced are damaged or defective. This means the body can not supply itself with the blood it needs.”

5. Complete blood count, or CBC

This blood test provides information about the cells in a person’s blood, including the amount of white blood cells, red blood cells, and platelets, and the concentration of hemoglobin and hematocrit. It is used to monitor many different health conditions.

Understanding these five terms has helped me better manage my blood disorders. I hope this information gets you started on researching your own fight.


Note: PNH News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of PNH News or its parent company, BioNews, and are intended to spark discussion about issues pertaining to paroxysmal nocturnal hemoglobinuria.