Sickle Cell Trait (SCT) is the inheritance of one gene for sickle hemoglobin (Hemoglobin S) and one for normal hemoglobin (Hemoglobin A). SCT is a genetic condition based on inheritance. It is most commonly found in persons with ancestry from Mediterranean, Middle Eastern, Indian, African, Caribbean, and South and Central America. Therefore, SCT is a required screen for every new born in the United States. One in 12 African Americans have SCT, whereas only one in 2,000-10,000 Caucasian Americans.
During intense or extensive exertion, the sickle hemoglobin can change the shape of red blood cells from round to quarter-moon, or “sickle”. The change, known as “exertional sickling”, can pose a grave risk for some athletes. The sickled cells can create a “logjam” in the blood stream and lead to Ischemic Rhabdomyolysis (Rhabdo), which is characterized as the rapid breakdown of muscles that are starved for blood. Rhabdo will be covered in greater detail later in this statement. Heat, dehydration, altitude, and asthma can increase the risk for and worsen sickling, even when exercise is not “all-out”. Most SCT related deaths have been associated to football and most of these cases are very similar:
- Sickling athletes may be on-field for a brief period of time, sprinting only 800-1600 meters, often early in the season.
- This can also occur during repetitive running of hills or stadium steps, during intense sustained strength training, if the tempo increases at the end of the training session, or at the end of a practice when athletes run wind sprints.
- Sickling can begin in only 2-3 minutes of sprinting, or in any other all out exertion, and sickling can quickly increase to grave levels is the stricken athlete struggles on or is urged on by the coach.
However, other sickling cases have been documented in sprinting, mid-distance, and distance training. Therefore, all sports at Ohio Wesleyan University have conditioning programs that make them susceptible to causing “exertional sickling”.
Is Sickle Cell Trait the same as Sickle Cell Disease?
No. A person who carries the Sickle Cell Trait has enough hemoglobin for their red blood cells to function normally due to them having one of each gene (Hemoglobin A and S). A person who has Sickle Cell Disease, inherits abnormal genes from both parents. Sickle Cell Disease is a life-long condition that may require ongoing medical treatment and follow-up. If you have Sickle Cell Trait it will NOT develop into Sickle Cell Disease. However, if you have children with another SCT carrier, your offspring may be born with Sickle Cell Disease.
Exertional Rhabdomyolysis (Rhabdo) is the breakdown of muscle fibers resulting in the release of its contents into the bloodstream. This causes an increase in protein which can cause kidney failure and/or cardiac complications. This increase in protein also will result in discoloration of urine that is different from dehydration. A person suffering from Rhabdo will present with urine being more of a brownish tint (tea or cola colored) as opposed to a deeply yellow or amber color of a person experiencing dehydration.
Although anyone who performs strenuous exercise can develop Exertional Rhabdo, research shows that individuals with the SCT may be at in increased risk of suffering from complications. There have been recent documented Rhabdo outbreaks at colleges and universities that involve multiple sports, genders, and student-athletes with different ethnic backgrounds.
Signs and Symptoms of Rhabdo include:
- Muscular Weakness
- Muscular Swelling
- Muscular Pain and/or cramping
- Darkened Urine, 24-48 hours post workout
A student-athlete with SCT is not disqualified from participating in athletics, because simple precautions seem to be adequate. These precautions center on proper conditioning techniques and making slight modifications if necessary.
Signs and Symptoms
Sickling collapse has been mistaken for cardiac or heat collapse. However, cardiac collapse tends to be instantaneous, has no muscle cramping, and an athlete with ventricular fibrillation hits the ground and no longer talks. Heat collapse normally occurs at the end of practice and the athlete has an elevated core temperature. As stated above, sickling collapse normally occurs within the first 30 minutes of a workout.
Sickling is also commonly confused with heat cramping. Athletes who have experienced both syndromes know the difference, as indicated by the following distinctions:
- Heat cramping often has muscle twinges, whereas sickling has none.
- The pain with both is very different. Heat cramping pain is much more excruciating.
- What keeps the athlete from participating is different. Persons suffering from heat cramps complain of muscles “locking up”, while sickling players slump to the ground with “weak” muscles.
- Physical characteristics are different. Heat crampers writhe and yell in pain, with muscles that are visibly contracted, whereas sicklers lie fairly still, do not yell in pain, with muscles that both look and feel normal.
- The response to initial treatment is different. Sickling players caught early enough and treated correctly will recover faster than players with major heat cramping.
Granted, not all athletes who sickle present the same way. Some players stop exercising and take a rest. This allows for their body to regain oxygen in the lungs which causes most red blood cells to then revert back to normal shape. When this occurs the athlete soon feels better and is ready to continue. This simple self-limiting treatment can save lives.
For the student-athlete with SCT the following guidelines should be applied:
- Slowly build up the intensity in workouts while training.
- Have fitness tests scheduled later in the training program. Evaluate their performance once they are acclimated to the stress about to be placed upon them.
- Allow SCT athletes to set their own pace while conditioning.
- Implement a slow and gradual preseason conditioning program that prepares them for the start of practices.
- Provide adequate rest and recovery between repetitions, especially during end of practice wind sprints or intense station conditioning drills.
- Provide alternatives for conditioning testing rather than serial sprints or timed runs, especially if they are not sport specific.
- Stop activity immediately when an athlete begins experiencing symptoms such as muscle pain, abnormal weakness, undue fatigue, or being “out of breath”.
- Stay hydrated at all times, especially in hot and humid conditions.
- Do not use high caffeine energy drinks and supplements as they may contribute to dehydration.
- Maintain proper asthma management.
- Refrain from extreme exercise during acute illness, if feeling ill, or experiencing a fever.
- Modify training when experiencing a change in altitude (even as little as 2,000 ft.).
- Seek prompt medical care, when experiencing unusual physical distress.
In the event of a sickling collapse, treat it as a medical emergency and do the following:
- Check vital signs
- Cool the athlete if necessary
- If vital signs worsen, call 911 and attach an AED.
- Inform EMS and/or ER staff to expect explosive rhabdomyolysis and grave metabolic complications.
SCT and OWU
There is currently legislation that will require all NCAA Division III institutions to either confirm SCT status in all incoming student-athletes for the 2013-14 academic year or have student-athletes sign a written release declining the SCT test during their pre-participation physical examination (PPE).
The Ohio Wesleyan University Department of Athletics in coordination with the Student Wellness Center will go about three (3) different ways of meeting these NCAA requirements. Each way will require the student athlete to complete and sign the “Sickle Cell Trait Testing Agreement, Waiver, and Release of Claims” form (Appendix A, link below).
- A student-athlete will report to campus prior to the season beginning with a documentation of SCT status as provided by their home physician or when completed at birth. The student athlete will acknowledge this on their waiver form. This documentation will be kept in their medical file in the Athletic Training Room. If the student-athlete is a SCT carrier and they have not met with a Hematologist, they will be offered a meeting with a local Hematologist as described below (Education, Step 1). If they have already met with a Hematologist at home, the student-athlete can waive the local referral and the Department of Athletics will begin with Step 2 in the Education section below.
- A student-athlete will report to campus and choose to be tested for SCT as part of their Pre-Participation Examination. Due to a period of time being elapsed between the test being performed and results being returned, the student-athlete will need to undergo baseline education and sign a waiver.
- A student-athlete opts out of testing for SCT and receives baseline education and signs a waiver stating that they do not wish to be tested for SCT.
Education for Ohio Wesleyan University Student-Athlete with Sickle Cell Trait
If a student-athlete tests positive for SCT they will be required to go through the following steps:
- Step One – Referral to a Hematologist for initial consultation on what being a SCT carrier means and provide them the opportunity to ask questions about how it may affect their competitive and personal life with an expert in the area. A member of the Athletic Training staff will attend this appointment.
- Step Two – After the appointment with a Hematologist, there will be a meeting held on campus that will be for the student-athlete, Head Coach, AT staff member and Jason Diehl, Head Team Physician. This will provide an opportunity to set a plan for prevention, recognition, and treatment of a sickling episode.
- Step Three – If applicable, there could be a meeting with the Head Coach, AT staff member, and teammates about SCT and exertional sickling. This will provide an opportunity for all involved to set a plan for prevention, recognition, and treatment of a sickling episode, due to the fact that Head Coaches are not able to attend off-season conditioning or volunteer workouts.