Red Blood Cell Conditions

There are a variety of conditions that contribute to abnormal RBC function or counts.

Condition	Physiology	WBC	RBC	HGB	HCT	MCV	MCH	MCHC	RDW	PLT	Morphology	Followup Tests
Blood loss/hemorrhage			N/↓	N	N	N	N	N	N		Normal
Iron Deficiency Anemia	Insufficient erythropoiesis		N/↓	N/↓	↓	↓	↓	↓	↑		Hypo/micro Ovals, pencils Tears, targets (occasional)
Anemia of Chronic Inflammation	Insufficient erythropoiesis										Normal or Hypo/micro
Sideroblastic Anemia	Ineffective erythropoiesis Deficient protoporphyrin synthesis		↓	↓	↓	N/↓	N/↓	N/↓	↑		Dual population Normochromic/normocytic Hypo/micro Pappenheimers
Lead poisoning			↓	↓	↓	N/↓	N/↓	N/↓	N		Normal OR hypo/micro Stomatocytes Coarse basophilic stippling
Thalassemia	Ineffective erythropoiesis										Hypo/micro
Megaloblastic Anemia	Ineffective erythropoiesis Vitamin B12 deficiency Folic acid deficiency Certain cancers or drugs					↑		N			Macrocytic/normochromic
Liver disease						↑		N			Macrocytic/normochromic
Aplastic Anemia	Insufficient erythropoiesis Hypocellularity due to autoimmune destruction					↑

Insufficient Erythropoiesis

• Iron deficiency anemia
• Erythropoietin deficiency (renal disease)
• Loss of erythroid precursors
  • Aplastic anemia (autoimmune)
  • Infection
  • Destruction/suppression of erythroid precursors (cancers, granulomas, fibrosis)

Anemias

• Ineffective erythropoiesis
  • Defective precursors made that are destroyed or function poorly
• Insufficient erythropoiesis
• Blood loss (acute or chronic)
• Increased RBC destruction (hemolytic anemia)
  • Shortened cell survival
  • Intrinsic RBC defects
  • Extrinsic RBC defects