What are the signs, symptoms, and management of anemia?

Signs, Symptoms, and Management of Anemia

Anemia is characterized by decreased hemoglobin concentration or red blood cells, requiring prompt evaluation of underlying causes and appropriate management based on etiology, severity, and patient factors.

Clinical Presentation

Signs and Symptoms

• Fatigue and exhaustion that interferes with normal functioning and is less likely to be ameliorated by rest 1
• Exercise dyspnea, syncope, headache, vertigo, and chest pain 1
• Abnormal menstruation in female patients 1
• Pallor (visible in skin, mucous membranes) 1
• Tachycardia and heart murmurs 1
• Neurologic symptoms in severe cases or specific deficiencies 1
• Pica (craving for ice or non-food substances), restless leg syndrome, and hair loss in iron deficiency 1

Specific Manifestations by Type

• Iron deficiency: angular stomatitis, glossitis, koilonychia, blue sclerae 1
• Vitamin B12 deficiency: neurologic symptoms, macrocytosis 1
• Chronic disease anemia: often concurrent with underlying condition symptoms 1
• Hemolytic anemia: jaundice, splenomegaly 1

Diagnostic Approach

Initial Assessment

• Complete blood count (CBC) with indices to characterize anemia and identify other cytopenias 1
• Visual review of peripheral blood smear to confirm size, shape, and color of RBCs 1
• Mean corpuscular volume (MCV) classification 1, 2:
  • Microcytic (<80 fL): iron deficiency, thalassemia, anemia of chronic disease
  • Normocytic (80-100 fL): hemorrhage, hemolysis, bone marrow failure, chronic inflammation
  • Macrocytic (>100 fL): vitamin B12/folate deficiency, alcoholism, medications, MDS

Further Workup Based on MCV

• Microcytic anemia: serum ferritin (diagnostic at <12 μg/dL), iron studies, TIBC 1, 2
• Normocytic anemia: reticulocyte count to assess bone marrow response 1
• Macrocytic anemia: vitamin B12 and folate levels, alcohol history 1
• Elevated red cell distribution width (RDW >14.0%) with microcytosis strongly suggests iron deficiency 2

Reticulocyte Index Assessment

• Low RI (<1.0): indicates decreased RBC production (iron/B12/folate deficiency, bone marrow dysfunction) 1
• High RI (>2.0): indicates blood loss or hemolysis 1

Specific Testing for Common Causes

Iron Deficiency Anemia

• Serum ferritin is the most powerful test (<12 μg/dL is diagnostic) 1, 2
• In inflammation, malignancy, or hepatic disease, use higher threshold (<100 μg/L) 2
• Transferrin saturation <30% helps confirm diagnosis 1, 2
• Gastrointestinal evaluation is necessary in men and postmenopausal women 1

Vitamin Deficiencies

• B12 and folate levels should be measured in patients with high MCV 1
• Homocysteine or methylmalonate can be tested in doubtful cases 1

Chronic Disease/Inflammation

• Elevated inflammatory markers (CRP, ESR) 1
• Normal or elevated ferritin with low transferrin saturation 1

Hemorrhage

• Stool guaiac testing, endoscopy findings 1
• Urine testing for microscopic hematuria 1

Management Strategies

Iron Deficiency Anemia

• Oral iron supplementation as first-line therapy 1, 2
• Initial therapy with 35-65 mg of elemental iron daily 1
• Assess response after one month (hemoglobin rise ≥1 g/dL) 1
• Intravenous iron for patients with oral intolerance, malabsorption, or severe anemia 1, 2
• Identify and treat underlying cause (especially GI evaluation in adults) 1

Vitamin Deficiencies

• B12 and folate deficiencies should be treated to avoid anemia 1
• Regular monitoring in high-risk patients (small bowel disease or resection) 1

Anemia of Chronic Disease

• Optimize treatment of underlying condition 1
• Consider erythropoiesis-stimulating agents (ESAs) in patients with insufficient response to intravenous iron 1
• Target hemoglobin level not above 12 g/dL with ESAs 1

Blood Transfusions

• Consider transfusion when hemoglobin is below 7 g/dL or higher if symptoms or risk factors are present 1
• Indications include 1:
  • Hemodynamic instability/shock
  • Comorbidities requiring higher hemoglobin targets
  • Need to increase hemoglobin acutely (pre-surgery, pregnancy)
  • Inability to maintain adequate hemoglobin despite iron infusions
• Follow transfusions with intravenous iron supplementation 1

Special Considerations

Cancer-Related Anemia

• Evaluate for multiple potential causes (cancer itself, chemotherapy, nutritional, blood loss) 1
• Consider both immediate correction (transfusion) and long-term management 1
• One unit of PRBC typically increases hemoglobin by approximately 1 g/dL 1

Inflammatory Bowel Disease

• Regular screening for iron deficiency and anemia 1
• Consider both iron deficiency and anemia of chronic disease 1
• Monitor for medication-related causes (azathioprine can cause cytopenias) 1

Elderly Patients

• Anemia is common and associated with increased morbidity and mortality 3
• Complete evaluation warranted even with mild anemia 3
• Consider "unexplained anemia" when standard workup is negative 4

Common Pitfalls to Avoid

• Not accepting dietary history alone as the cause of anemia without completing GI investigation 2
• Not accepting minor upper GI findings as the sole cause without completing lower GI evaluation 2
• Relying solely on hemoglobin and hematocrit for diagnosis, as these are late indicators 2
• Overlooking celiac disease as a potential cause, even without GI symptoms 2
• Assuming normal ferritin excludes iron deficiency in patients with inflammatory conditions 2