Is there a test for PNH?
Yes. If you show signs of hemolysisThe destruction of red blood cells by complement, a part of the body’s natural defense system. Hemolysis is the main cause of the signs, symptoms, and serious health problems in PNH, including some that are life-threatening., your doctor may request a high-sensitivity flow cytometryThe gold standard test for confirming whether or not you have PNH. It counts the actual number of red and white blood cells affected by PNH in a small blood sample taken from your arm. The results indicate your clone size. Remember, even patients with small clone sizes can have PNH symptoms that may greatly limit their lives. test.1 Using a small sample of blood taken from your arm, this test measures the number of blood cells affected by PNHA disease where red blood cells are created without a protective protein. This causes them to burst (a process called hemolysis) and can result in serious health problems. Signs and symptoms include stomach pain, difficulty swallowing, anemia, shortness of breath, and fatigue. Life-threatening complications from PNH include blood clots, kidney failure, and damage to organs., also known as your clone sizeThe percentage of blood cells in your body affected by PNH.. A larger clone size means you have more PNH blood cells, but even small clone sizes can lead to PNH-related health problems.2 Your clone size may grow over time, so symptoms can get worse over time too, if your PNH is left untreated.1,3
How will my doctor monitor my PNH?
To monitor and track your PNH, your doctor will consider all of your lab test results, signs, and symptoms, which may vary from what other people with PNH experience. Because everyone is different, how they experience the disease might be different too. No single sign, symptom, or lab result defines PNH.4-8
Some lab tests that your doctor may order include lactate dehydrogenase (LDH) An enzyme found in red blood cells, released during hemolysis. Testing for LDH can help show how much hemolysis is happening in your body. level; complete blood count (CBC)A lab test that measures and evaluates several components and features of your blood, and detects a wide range of disorders. measurements—red blood cells (RBCs)A type of cell found in your blood that delivers oxygen and removes waste (carbon dioxide) in your body. Red blood cells affected by PNH are attacked and destroyed because they are missing a protective protein., white blood cells (WBCs)A type of cell found in your blood that helps your immune system fight disease and infection., and hemoglobin (Hgb)The oxygen-carrying, reddish-brown material found inside red blood cells. When it is released into the bloodstream during hemolysis, it becomes free hemoglobin. Free hemoglobin is harmful and can lead to serious health problems.; and flow cytometryThe gold standard test for confirming whether or not you have PNH. It counts the actual number of red and white blood cells affected by PNH in a small blood sample taken from your arm. The results indicate your clone size. Remember, even patients with small clone sizes can have PNH symptoms that may greatly limit their lives..1,5,9-12
Click on a word that is underlined with a light dotted line and an explanation of that word will appear.
Learn, what high sensitivity flow cytometry is, and why this test is used in PNH patients, from Dr. Ellen W. Friedman a doctor of blood and blood diseases.
References: 1. Borowitz MJ, Craig FE, DiGiuseppe JA, et al; for Clinical Cytometry Society. Cytometry Part B. 2010;78B:211-230. 2. Lee JW, Jang JH, Kim JS, et al. Int J Hematol. 2013;97:749-757. 3. Richards SJ, Barnett D. Clin Lab Med. 2007;27:577-590. 4. Hill A, Rother RP, Wang X, et al. Br J Haematol. 2010;149:414-425. 5. Parker C, Omine M, Richards S,et al; for International PNH Interest Group. Blood. 2005;106:3699-3709. 6. Meyers G, Weitz I, Lamy T, et al. Blood. 2007;110: Abstract 3683. 7. Nishimura J-I, Kanakura Y, Ware RE, et al. Medicine. 2004;83:193-207. 8. Hill A, Richards SJ, Hillmen P. Br J Haematol. 2007;137:181-192. 9. Hill A, Kelly R, Hillmen P. Blood. 2013;121:4985-4996. 10. Mohanty BD, De Castro CM. Am J Med. 2012;125:243-245. 11. Urbano-Ispizua A, Schrezenmeier H, Muus P, et al. An International PNH Registry study. Blood. 2011;118: Abstract 2102. 12. Lee JW, Jang JH, Lee JH, et al. Haematologica. 2010;95(s2):205-206.