A 35-year-old woman comes to the office due to reduced energy and fatigue. She reports heavy menstrual bleeding over the past 6 months. The patient is found to have hypochromic microcytic anemia. Iron supplementation is prescribed. A week later, a peripheral blood smear shows numerous enlarged red blood cells that have a bluish hue on Wright-Giemsa staining. The bluish color of these red blood cells is best explained by the presence of which of the following?

Question

A 35-year-old woman comes to the office due to reduced energy and fatigue.  She reports heavy menstrual bleeding over the past 6 months.  The patient is found to have hypochromic microcytic anemia.  Iron supplementation is prescribed.  A week later, a peripheral blood smear shows numerous enlarged red blood cells that have a bluish hue on Wright-Giemsa staining.  The bluish color of these red blood cells is best explained by the presence of which of the following?

Quizplus · Accepted Answer

11ec160b_3985_4810_9249_8b0a1eb1cfd9_MD0001_00 This patient has iron deficiency anemia (most likely due to menstrual blood loss), characterized by the presence of microcytic (ie, small), hypochromic (ie, pale) red blood cells (RBCs). Patients with iron deficiency anemia who receive iron replacement therapy experience enhanced erythropoiesis and accelerated release of reticulocytes into the bloodstream as the bone marrow attempts to correct the anemia. Reticulocytes (immature RBCs) are anucleate (like mature RBCs) but are enlarged and have a blue-gray hue on Wright-Giemsa staining. This bluish color (ie, polychromatophilia) is due to the presence of large amounts of ribosomal RNA necessary for adequate hemoglobin synthesis. The ribosomal RNA can be distinguished using a supravital stain that binds RNA (eg, new methylene blue) and appears as a blue, reticular (ie, net-like) substance. Ribosomal RNA is gradually degraded as the reticulocyte matures. After spending a day or more in the bloodstream, the maturation process is complete, and the reticulocyte transforms into a mature RBC, which has a lifespan of approximately 120 days. (Choices A and D) Young reticulocytes contain organelles necessary for cell development, including mitochondria and remnants of Golgi apparatus, which are also removed as the reticulocyte matures. However, it is the ribosomal RNA that imparts the bluish color on Wright-Giemsa staining. (Choice B) Heinz bodies consist of denatured hemoglobin precipitate and are associated with glucose-6-phosphate dehydrogenase deficiency. They cannot be seen on Wright-Giemsa staining but appear as round, peripheral RBC inclusions using a supravital stain. (Choice C) Histone proteins are found in the nucleus. During erythropoiesis, the erythroblast ejects its nucleus, forming a reticulocyte; because the reticulocyte does not have a nucleus, it does not contain histones. (Choice E) Howell-Jolly bodies are nuclear remnants visible on Wright-Giemsa staining as purple, round, peripheral RBC inclusions. They are associated with asplenia or hyposplenia because the spleen typically removes these nuclear remnants. Educational objective: Reticulocytes (immature red blood cells) appear as blue-gray (ie, polychromatophilic) red blood cells on Wright-Giemsa staining due to the presence of ribosomal RNA. In patients with iron deficiency anemia, iron supplementation results in increased bone marrow erythropoiesis and accelerated release of reticulocytes into the bloodstream.

A 35-Year-Old Woman Comes to the Office Due to Reduced