A 45-year-old female presents to clinic with worsening dyspnea on exertion and fatigue. She also notes an insatiable craving for detergent soap
- What is your differential for microcytic anemia?
- What is the next best test to confirm the diagnosis?
Click for answer:
Diagnosis: Iron Deficiency Anemia (IDA)
CBC findings suggestive of diagnosis:
(1) Microcytosis with elevated RDW, (2) Hypochyromic, microcytic cells on smear, (3) Thrombocytosis
Q1: What is your differential for microcytic anemia?
TAILS (see Box 1).
Q2: What is the next best test to confirm the diagnosis?
Ferritin and transferrin saturation.
Iron deficiency and thalassemia are the most common causes of micocytic anemia and occur concurrently. Thrombocytosis is often seen with iron deficiency, with or without anemia.
Microcytic Anemia Differential
• Thalassemia
• Anemia of chronic inflammation
• Iron deficiency
• Lead poisoning
• Sideroblastic anemia
CBC Pearls
• Thrombocytosis is often seen in the setting of iron deficiency
• Thrombocytosis is often seen in the setting of iron deficiency
• Always look for the cause of iron deficiency
The clinical history is important as the patient endorses pica. This refers to the uncontrollable craving for unusual, non-edible objects. Cravings for ice are most common but can also include clay, dirt, and soap. It is important to identify the cause for iron deficiency, which include reduced consumption, reduced absorption, or increased loss (e.g. bleeding). A thorough bleeding history, including menstruation, should be obtained. Endoscopy should be considered in those with higher pre-test probability for occult GI bleed. Celiac testing should be considered, including an IgA level, as patients can be asymptomatic from a GI perspective. In this scenario, although the patient has significant anemia and symptoms, she does not warrant emergent transfusion. Intravenous iron should be considered in an expedited manner, depending on resource availability.