What condition mimics sickle cell trait?

• A. Rhabdomyolysis
• B. Hemophilia
• C. Iron deficiency anemia
• D. G6PD deficiency

Answer: (A)

Exertional rhabdomyolysis is the situation that most closely mimics sickle cell trait in athletes. Both can present after intense, dehydration-prone exercise with muscle pain and weakness, and in rhabdomyolysis you often see dark urine from myoglobin and a very high CK. Sickle cell trait can lead to exercise intolerance and, in rare cases, muscle ischemia from red cell sickling under stress, which can produce a similar clinical picture. The key to telling them apart is testing: sickle cell trait will show HbS on electrophoresis with HbA present, whereas rhabdomyolysis shows elevated CK and myoglobin without evidence of HbS. The other conditions listed involve different problems (bleeding tendency, iron-deficiency anemia, or oxidative hemolysis) and don’t reproduce the same pattern of exercise-related muscle injury.