Erythrocyte Morphology and Hemoglobin

Grading Erythrocyte Morphology

• Erythrocyte morphology grading uses a scale of 0 to 4+.
• 0: Normal appearance or slight variation in erythrocytes.
• 1+: Only a small population of erythrocytes displays slight abnormality.
• 2+: More than occasional numbers of abnormal erythrocytes are seen in a microscopic field; equivalent to moderately increased.
• 3+: Severe increase in abnormal erythrocytes in each microscopic field; equivalent to many.
• 4+: The most severe state of erythrocytic abnormality, with the abnormality prevalent throughout each microscopic field.

Hemoglobin

• Hemoglobin is the main component of red blood cells (approximately 95% of cytoplasmic content).
• Also known as respiratory pigment.
• Concentration of Hb in RBCs is approximately 34 g/dL.
• Molecular weight is approximately 64,000 Daltons.
• Felix Seyler identified the respiratory protein hemoglobin in 1862.
• About 65% of cytoplasmic hemoglobin is produced before the nucleus is extruded. The remaining 35% is synthesized in early reticulocytes.
• Single most common complex organic molecule in vertebrates.
• 1 gram of hemoglobin can carry 1.34 mL of O₂.
• 1 gram of hemoglobin can carry a constant 3.47 mg of iron.

Hemoglobin Reference Ranges

• Children (8 to 13 years): 12 to 15 g/dL (conventional) / 120 to 150 g/L (SI)
• Adult (male): 14 to 18 g/dL (conventional) / 140 to 180 g/L (SI)
• Adult (female): 12 to 15 g/dL (conventional) / 120 to 150 g/L (SI)