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Foot-strike haemolysis in an ultramarathon runner.
Abid A Fazal1, Mary S Whittemore2, Katharine C DeGeorge2
1Department of Anesthesiology and Critical Care, University of Chicago Medical Center, Chicago, Illinois, USA.
BMJ Case Reports
|December 15, 2017
Summary
Repetitive foot striking during ultramarathons can cause mild anemia and red blood cell breakdown in runners. This condition, known as runner's pseudoanemia, is usually harmless and doesn't require medical intervention.
Area of Science:
- Sports Medicine
- Hematology
- Physiology
Background:
- Mild anemia and intravascular hemolysis are sometimes observed in endurance athletes.
- Potential causes include gastrointestinal bleeding and plasma volume expansion.
- Repetitive mechanical stress on red blood cells is another proposed mechanism.
Observation:
- A case report details a 41-year-old ultramarathon runner experiencing mild anemia and intravascular hemolysis.
- The patient was otherwise healthy.
- The findings were consistent with exercise-induced red blood cell destruction.
Findings:
- Repetitive forceful foot striking during ultramarathon running can lead to mechanical lysis of red blood cells in the feet.
- This results in a mild macrocytic anemia and intravascular hemolysis.
- The condition is often termed 'runner's pseudoanemia'.
Implications:
- Runner's pseudoanemia is typically clinically insignificant and does not necessitate treatment.
- Unexplained anemia can cause patient anxiety and lead to unnecessary, costly diagnostic tests.
- Routine complete blood count screening may not be indicated for healthy, asymptomatic endurance athletes.
