Fungal Infections

Pathophysiology
Numerous types of fungi live on and in our bodies without causing harm; they are held in check by competing bacteria and our immune system. Disease-causing fungi can be divided into two groups: filamentous fungi and yeasts. Filamentous fungi are made up of branching threads known as hyphae; yeasts are single-celled organisms. The most common fungal infections are superficial and caused by Tinea, a filamentous fungi and Candida albicans, a yeast. Heat, humidity, immunocompromised states, long term antibiotic use, diabetes, and steroid therapy predispose people to both types of fungal infections. Fungal infections are more common in the summer and exerted by wearing synthetic clothing and sweating.

Tinia Infections
Tinea infections are caused by a group of fungi (ringworm) that live on keratinous structures and invade dead layers of the host's skin, hair, and nails; the transmission routes are direct contact with an infected person or animal or with contaminated soil. Clinically, tinea infections are classified according to the body region involved/infected: tinea capitis (scalp), tinea corporis and versicolor (trunk and extremities), tinea manuum and tinea pedis (palms, soles, and interdigital webs), tinea cruris (groin), tinea barbae (beard area and neck), tinea faciale (face), and tinea unguium (nails).

Candida Albicans (Yeast) Infections
Candida albicans skin infections may closely mimic tinea crurisare but are usually moister, more inflammatory, and associated with satellite macules, pustules, and scales. Unlike Tinea, Candida may also infect the mucus membranes of the mouth, vagina, penis, and eye. These infections are red, itchy, moist and often associated with a yeasty odor and a white cheese-like discharge. Most mucosal infections result from long-term antibiotic use.

Prevention

• Avoid communal baths.
• Keep potentially affected areas (between toes, genitals, skin folds) clean and dry.
• People participating in contact sports are pre-disposed to tinea infections.

Assessment

• Both Tinea and Candida skin infections present with localized itching and red rash. Candida may exhibit satellite lesions and pustules.
• Vaginal Candida infections typically present with white, cheesy discharge and yeasty smell.
• In the mouth, Candida shows up as thick, white lacy patches on the tongue, lips, gums, or inside of the patient's cheeks. The lesions are painful and swallowing may be difficult.
• Candida infections on the scrotum often present as red bumps.

Treatment

• Treatment varies and is based on the anatomic location of the infection. Most localized fungal infections may be treated with numerous topical antifungal agents: clotrimazole, econazole, ciclopirox, miconazole, ketoconazole, or nystatin prepared as creams, suppositories, lozenges, etc. Systemic or persistent infections are treated with oral antifungal therapy using either fluconazole or itraconazole and require liver function tests.
• For skin rashes from either both Tinea or Candida, apply topical Lac-hydrin and Clotrimazole twice a day for 3-4 weeks; wash and dry thoroughly before each application.
• For oral Candida infections dissolve a Clotrimazole lozenge twice a day for 7-14 days.
• Begin a Level 3 Evacuation if S/Sx are mild and antifungals are unavailable or the patient does not respond. Begin a Level 2 Evacuation if patient is immunosuppressed or a systemic Candida infection is suspected.

Don't know where to begin or what to do? Take one of our wilderness medicine courses. Guides and expedition leaders should consider taking our Wilderness First Responder course.

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