Quantitative and functional abnormalities of certain RBC membrane proteins (alpha- and beta-spectrin, protein 4.1, F-actin, ankyrin) cause hemolytic anemias.Ībnormalities of RBC morphology often suggest the presence and cause of hemolysis (see table Red Blood Cell Morphologic Changes in Hemolytic Anemias Red Blood Cell Morphologic Changes in Hemolytic Anemias ). Alpha-thalassemia is particularly common among people with African, Mediterranean. read more, thalassemias Thalassemias Thalassemias are a group of inherited microcytic, hemolytic anemias characterized by defective hemoglobin synthesis. It is caused by homozygous inheritance of genes for hemoglobin. read more (eg, sickle cell disease Sickle Cell Disease Sickle cell disease (a hemoglobinopathy) causes a chronic hemolytic anemia occurring almost exclusively in people with African ancestry. Hemoglobin molecules consist of polypeptide chains whose chemical structure is genetically. read more ), and hemoglobinopathies Overview of Hemoglobinopathies Hemoglobinopathies are genetic disorders affecting the structure or production of the hemoglobin molecule. read more ), disorders of RBC metabolism (eg, glucose-6-phosphate dehydrogenase (G6PD) deficiency Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked enzymatic defect common in people with African ancestry that can result in hemolysis after acute illnesses or intake of oxidant. Leukopenia, thrombocytopenia, arterial and venous thromboses. read more ), acquired cell membrane disorders (eg, paroxysmal nocturnal hemoglobinuria Paroxysmal Nocturnal Hemoglobinuria (PNH) Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder characterized by intravascular hemolysis and hemoglobinuria. Symptoms, generally milder in hereditary. Even at the often-quoted estimate of 42.8 mmol/l (2.5 mg/dl) at which at scleral icterus is detected, approximately one-third of medical examiners in our study did not detect scleral icterus.Abnormalities include hereditary cell membrane disorders (eg, hereditary spherocytosis Hereditary Spherocytosis and Hereditary Elliptocytosis Hereditary spherocytosis and hereditary elliptocytosis are congenital red blood cell (RBC) membrane disorders that can cause a mild hemolytic anemia.

Level of training did not appear to influence sensitivity, as 3 of 11 apparent false-negatives (total serum bilirubin = 66.7 mmol/l and the absence of detection of scleral icterus) were not attributable to medical students (p = 0.278). Level of training appeared to influence specificity, as 6 of 8 apparent false-positives (total serum bilirubin = 12.0 mmol/l and the presence of scleral icterus) were attributable to medical students. At a total serum bilirubin of 42.8 mmol/l (2.5 mg/dl) and 53.0 mmol/l (3.1 mg/dl), 58% (95% confidence interval 33-80%) and 68% (95% CI 46-85%) of examiners detected the presence of scleral icterus, respectively. Sixty-two medical observers at various levels of medical training examined six patients for the presence or absence of scleral icterus in a double-blind survey.

Scleral icterus