Paroxysmal Nocturnal Hemoglobinuria: Symptoms & Signs

Medically Reviewed on 8/4/2020

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, chronic disease that results in an abnormal breakdown of red blood cells. When urine is concentrated overnight by the kidneys as a person with PNH sleeps, the morning urine may turn reddish to a darker cola color. This phenomenon led to the designation of the condition as nocturnal.

Signs and symptoms of PNH include

Other associated symptoms and signs can include

Causes of paroxysmal nocturnal hemoglobinuria (PNH)

PNH arises due to a spontaneous genetic mutation in a gene known as PIGA. This mutation causes red blood cells to become unusually fragile and prone to break down. The genetic mutation that causes PNH is not inherited from the parents but arises spontaneously.

Other paroxysmal nocturnal hemoglobinuria symptoms

Jameson, J. Larry, et al. Harrison's Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.