BMJ Case Reports 2017; doi:10.1136/bcr-2017-220661
  • Reminder of important clinical lesson

Foot-strike haemolysis in an ultramarathon runner

  1. Katharine C DeGeorge2
  1. 1 Department of Anesthesiology and Critical Care, University of Chicago Medical Center, Chicago, Illinois, USA
  2. 2 Department of Family Medicine, University of Virginia, Charlottesville, Virginia, USA
  1. Correspondence to Dr Katharine C DeGeorge, KD6FP{at}
  • Accepted 27 November 2017
  • Published 13 December 2017


This case report describes mild anaemia and intravascular haemolysis in an otherwise healthy 41-year-old ultramarathon runner. In long-distance endurance athletes, trace gastrointestinal bleeding and plasma volume expansion are recognised sources of mild anaemia, often found incidentally. However, repetitive forceful foot striking can lead to blood cell lysis in the feet, resulting in a mild macrocytic anaemia and intravascular haemolysis, as was demonstrated in the patient described herein. Mild anaemia in runners, often called ‘runner’s pseudoanaemia’, is typically clinically insignificant and does not require intervention. However, an unexplained anaemia can cause undue worry for otherwise healthy patients and lead to costly further testing, providing an argument against routine testing with complete blood counts in healthy, asymptomatic patients.


  • Contributors AAF was the major contributor to writing the manuscript. All authors read and approved the final manuscript. KCD initially saw the patient in clinic, provided guidance for the content of the manuscript and provided substantial editing for the manuscript. MSW revised the manuscript critically for important intellectual content.

  • Competing interests None declared.

  • Patient consent Obtained.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Register for free content

The full text of all Editor's Choice articles and summaries of every article are free without registration

The full text of Images in ... articles are free to registered users

Only fellows can access the full text of case reports (apart from Editor's Choice) - become a fellow today, or encourage your institution to, so that together we can grow and develop this resource

Don't forget to sign up for content alerts so you keep up to date with all the case reports as they are published, and let us know what you think by commenting on the Editor's blog

Navigate This Article