Differential Diagnosis for High Red Blood Cells with Low MCV, MCHC, MCH, and RDW

Single Most Likely Diagnosis

• Iron Deficiency Anemia: This is the most likely diagnosis due to the low MCV (mean corpuscular volume), MCH (mean corpuscular hemoglobin), and MCHC (mean corpuscular hemoglobin concentration) values, which are indicative of microcytic hypochromic anemia. The high red blood cell count may be a compensatory response to the anemia.

Other Likely Diagnoses

• Thalassemia: This genetic disorder can cause microcytic anemia with low MCV, MCH, and MCHC values. The normal hemoglobin and hematocrit levels may be due to the body's compensation for the anemia.
• Anisopoikilocytosis: This condition is characterized by a variation in red blood cell size and shape, which can lead to low MCV and MCH values. However, the low RDW (red cell distribution width) value may not be consistent with this diagnosis.
• Chronic Disease: Chronic diseases such as chronic kidney disease or chronic infections can cause microcytic anemia with low MCV, MCH, and MCHC values.

Do Not Miss Diagnoses

• Polycythemia Vera: Although the hemoglobin and hematocrit levels are normal, polycythemia vera can cause an increase in red blood cell count. It is essential to rule out this diagnosis, as it can lead to thrombotic complications if left untreated.
• Dehydration: Dehydration can cause a relative increase in red blood cell count, which may be misinterpreted as polycythemia. It is crucial to assess the patient's hydration status and repeat the lab tests if necessary.

Rare Diagnoses

• Sideroblastic Anemia: This rare genetic disorder can cause microcytic anemia with low MCV, MCH, and MCHC values. However, it is often associated with increased iron stores, which may not be consistent with the patient's lab results.
• Myelodysplastic Syndrome: This group of disorders can cause microcytic anemia with low MCV, MCH, and MCHC values. However, it is often associated with other cytopenias and morphological abnormalities in the bone marrow.