The classic sign of<unk>  is red discoloration of the urine due to the presence of hemoglobin and hemosiderin from the breakdown of red blood cells. As the urine is more concentrated in the morning, this is when the color is most pronounced. This phenomenon mainly occurs in those who have the primary form of<unk> , who will notice this at some point in their disease course. The remainder mainly experience the symptoms of anemia, such as tiredness, shortness of breath, and palpitations. A small proportion of patients report attacks of abdominal pain, difficulty swallowing and pain during swallowing, as well as erectile dysfunction in men; this occurs mainly when the breakdown of red blood cells is rapid, and is attributable to spasm of smooth muscle due to depletion of nitric oxide by red cell breakdown products. Forty percent of people with<unk>  develop thrombosis (a blood clot) at some point in their illness. This is the main cause of severe complications and death in<unk> . These may develop in common sites (deep vein thrombosis of the leg and resultant pulmonary embolism when these clots break off and enter the lungs), but in<unk>  blood clots may also form in more unusual sites: the hepatic vein (causing Budd-Chiari syndrome), the portal vein of the liver (causing portal vein thrombosis), the superior or inferior mesenteric vein (causing mesenteric ischemia) and veins of the skin. Cerebral venous thrombosis, an uncommon form of stroke, is more common in those with<unk> .
Paroxysmal nocturnal hemoglobinuria
Paroxysmal cold hemoglobinuria
Hereditary spherocytosis
Beta thalassemia
Congenital hemolytic anemia
Hemoglobinemia
Alpha-thalassemia
Congenital dyserythropoietic anemia type II