Hémoglobinurie

Hémoglobinurie is a medical condition characterized by the presence of hemoglobin in the urine. Hemoglobin is a protein found in red blood cells that carries oxygen. Normally, hemoglobin remains within the red blood cells. When red blood cells break down excessively or are damaged, hemoglobin can be released into the bloodstream and subsequently filtered out by the kidneys, appearing in the urine.

The most common cause of hemoglobinurie is hemolysis, which is the premature destruction of red blood cells. This hemolysis can occur for a variety of reasons, including certain genetic disorders like paroxysmal nocturnal hemoglobinuria or sickle cell anemia, autoimmune conditions where the body's immune system attacks its own red blood cells, infections that damage red blood cells, or exposure to certain toxins or medications. Mechanical damage to red blood cells, such as during strenuous exercise (exercise-induced hemoglobinurie) or with prosthetic heart valves, can also lead to this condition.

The presence of hemoglobin in the urine typically results in a reddish or brownish discoloration of the urine, often described as cola-colored or port-wine colored. While the presence of hemoglobin in urine is the defining feature, symptoms can vary depending on the underlying cause. These may include fatigue, jaundice (yellowing of the skin and eyes), abdominal pain, back pain, and shortness of breath.

Diagnosis of hemoglobinurie involves urine tests to detect the presence of hemoglobin and blood tests to assess red blood cell count, hemolysis markers, and identify the underlying cause. Treatment focuses on addressing the root cause of the red blood cell destruction. This might involve medication to suppress the immune system in autoimmune cases, blood transfusions, or specific therapies for genetic disorders. In cases of exercise-induced hemoglobinurie, reducing or modifying strenuous activity may be recommended.