Cover me! Understanding dermatology in Sports and Exercise Medicine – part III

Fungal Infections

1. Onychomycosis

Onychomycosis is a common disorder that is difficult to cure. Signs include nail discoloration, thickening, cracking, and fragility (see figure 1). In addition, athletes are twice as likely to develop the disease than the general population. The risk of developing onychomycosis is increased by the warm environmental conditions, occlusive and moist footwear, shared hygiene spaces, and foot or toenail trauma. Once infected, onychomycosis treatment is long and requires strict compliance. Treatment carries the risk of significant side effects, and recurrence rates remain high. Avoiding infection is a potent first line of defense and includes well-kept toenails and thorough washing of laundry. Furthermore, technological improvements such as synthetic, moisture-wicking socks and well-ventilated mesh shoes reduce moisture and injury⁽³⁾.

Topical and oral agents are available for fungal nail infection treatments. Unfortunately, oral antifungal agents require a long treatment period and thus may have more side effects⁽⁴⁾. In contrast, topical agents are inconvenient, and results are often disappointing. In addition, creams and other topical medications are usually ineffective against nail fungus because nails are too complex for external applications to penetrate.

Figure 1: Onychomycosis

2. Tinea Pedis (Athlete’s Foot)

Athlete’s foot is a fungal skin infection that usually begins between the toes and can extend to the sides of the feet. It commonly occurs in people whose feet have become very sweaty while confined within tightfitting shoes. Aquatic athletes, runners, soccer, and basketball players experience tinea pedis two to four times more commonly than non-athletes⁽⁵⁾. The signs and symptoms include an itchy, scaly rash, but tinea pedis is often asymptomatic⁽⁶⁾. As a result, athletes may mistake the signs for dry skin. Furthermore, athlete’s foot is contagious and spread via contaminated floors, towels, or clothing. The differential diagnosis for tinea pedis includes xerosis (dry skin), eczema, psoriasis, and pitted keratolysis.

Tinea pedis is effectively treated with topical therapy twice daily for several weeks. However, in resistant disease cases, clinicians use oral antifungal treatment. Furthermore, wearing synthetic socks wicks moisture from the foot, preventing hyperhydration and tinea pedis⁽⁷⁾.

3. Tinea Corporis Gladiatorum

Tinea corporis is common in wrestling; however, any athlete with intense skin-to-skin contact may develop ringworm. The fungus resides asymptomatically in some athletes’ scalps or develops into red, round, scaling papules and plaques on the head, neck, and arms (which correlate to the skin-to-skin contact areas) (see figure 2). Early lesions may be confused for acne, eczema, early herpes gladiatorum, and early impetigo. Clinicians can treat the fungal infection orally⁽⁸⁾.

Figure 2: Tinea corporis

Bacterial Infections

Most bacterial infections in athletes occur on exposed skin, corresponding to intense skin-to-skin contact during practice and competition, although lesions may also appear beneath athletic equipment. Acquiring turf burns, shaving body hair cosmetically, wearing athletic tape and elbow pads, and not showering before using communal pools increase the risk of developing bacterial infections⁽⁹⁾.

Staphylococcus Aureus (Staph) is the most commonly transmitted bacterial skin infection amongst athletes’. The disease can manifest in several forms (see table 1)⁽¹⁰⁾. In addition, Streptococcus (Strep) conditions present similarly to Staph infections. Effective treatment for Staph and Strep infections includes the application of topical ointments twice daily and administering oral therapy three times per day for 10–14 days. Athletes allergic to penicillin and similar medications should use erythromycin or clindamycin.

Methicillin-resistant Staph Aureus (MRSA) is a strain of staph infection that has become resistant to common antibiotics over time. Although effective treatment is still available, MRSA infections are often misdiagnosed initially as typical staph infections. This misdiagnosis can prolong the infection and allow it to spread. Furthermore, MRSA may take the form of a solitary abscess that requires incision and drainage or any other type of Staph infection, including impetigo and folliculitis.

Athletes may also asymptomatically carry Staph in their perianal region and nares or Strep in their throat, so clinicians should culture these areas after repeated infection. It is essential to realize that systemic findings (lymphadenopathy, pharyngitis, and post-streptococcal glomerulonephritis) may result⁽¹⁰⁾. Treatment of MRSA can be notoriously difficult to clear and often requires prolonged and repeated antibiotic therapy.

Table 1: Bacterial Skin Infections

Viral Infections

1. Herpes Simplex Virus (HSV)

Herpes simplex infection is prevalent in wrestlers and rugby players⁽¹²⁾. The clinical presentation is that of a group of vesicles on an erythematous plaque (see figure 3). Lesions are all at the same stage of development, unlike herpes zoster, which has lesions at various stages of development. Rupture of the HSV vesicles may result in erosions. Transmission is primarily through skin-to-skin contact. Clinicians should identify infected athletes promptly and exclude them from direct contact with their teammates to halt the spread. Rapid administration of antiviral treatment may accelerate an athlete’s return to sport. In athletes prone to frequent recurrences of HSV, clinicians may prescribe prophylactic antivirals.

Figure 3: Herpes Simplex Virus. Grouped vesicles on an erythematous base all at the same stage of development.

2. Molluscum Contagiosum

Poxvirus causes molluscum contagiosum and is common in athletes involved in contact sports. Typically there are multiple, asymptomatic white or skin-colored papules with a central indentation (see figure 4). The lesions usually resolve spontaneously, but for those athletes wanting treatment, there are numerous options, such as removal with a curette or destruction with liquid nitrogen, trichloracetic acid, or cantharidine.

Figure 4: Molluscum contagiosum

3. Verruca

Verruca can occur on any skin surface. The bacterial infection is transmitted by direct contact. However, locker rooms and shower floors may also act as reservoirs. Swimmers may be particularly susceptible to plantar verruca⁽¹³⁾. Clinicians may treat verruca using cautery and cryotherapy. Unfortunately, these treatments can cause significant morbidity and interfere with training. Athletes with plantar verruca should wear sandals while showering in shared facilities.

Skin Infection Prevention

The American Academy of Dermatologists published guidelines for athletes to follow to prevent bacterial and fungal infections. Hygiene is a cornerstone of prevention, and athletes who train and compete frequently should practice good hygiene with the highest standards.

1. Keep cuts and scrapes clean and covered with a bandage until healed. A cut or scrape weakens the skin’s defense and allows germs that cause infections to enter.
2. Prevent blisters to reduce infections. To help prevent blisters, athletes should consider using specialized gloves and socks or wearing two pairs of socks. Athletes should also make sure that their footwear fits properly.
3. Wear moisture-wicking clothes. This helps keep the athlete’s skin dry and prevents germs from growing.
4. Wear sandals in the locker room.
5. Shower after every practice and game. In addition, athletes should use antimicrobial soap.
6. Do not share personal care items. Athletes should always use a clean towel after showering and use their own towels, soaps, razors, and other personal care items.
7. Wash clothes and towels after each use. Athletes should wash sports bags regularly.
8. Disinfect equipment, including protective gear, daily.
9. Perform regular skin checks. Athletes should check their skin daily, especially in high-risk sports such as wrestling.

Conclusion

Cutaneous infections are relatively common in athletes. Early recognition will result in appropriate treatment, reduced time off sports, and reduced infectious disease. However, prevention is always best, and athletes should maintain good hygiene standards to ensure optimal skin health and performance.

References

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