Rouleaux formation on a peripheral smear is most strongly associated with which condition?

Rouleaux formation on a peripheral smear is most strongly associated with which condition?

• A. Iron deficiency anemia
• B. Multiple myeloma
• C. Megaloblastic anemia
• D. Thalassemia

Answer: (B)

Rouleaux formation happens when plasma protein levels are high, especially immunoglobulins, which reduces the charge between red blood cells and lets them stack like coins. This stacking is most striking in conditions with a monoclonal gammopathy, where a single type of immunoglobulin is greatly elevated, as in multiple myeloma. So, the smear finding of prominent rouleaux is most strongly associated with multiple myeloma. By contrast, the other conditions listed produce different red cell morphologies (microcytosis with iron deficiency or thalassemia, or macrocytosis with megaloblastic anemia) rather than this stacking pattern.

Rouleaux formation happens when plasma protein levels are high, especially immunoglobulins, which reduces the charge between red blood cells and lets them stack like coins. This stacking is most striking in conditions with a monoclonal gammopathy, where a single type of immunoglobulin is greatly elevated, as in multiple myeloma. So, the smear finding of prominent rouleaux is most strongly associated with multiple myeloma. By contrast, the other conditions listed produce different red cell morphologies (microcytosis with iron deficiency or thalassemia, or macrocytosis with megaloblastic anemia) rather than this stacking pattern.