C. albicans: Causes, Symptoms, and Treatment

Candida albicans is a single-celled fungus, a type of yeast, commonly found as a normal inhabitant of the human body. This microorganism lives in harmony with its host as a commensal organism that does not cause harm. It is a natural part of the human microbiome and can be detected in the gastrointestinal tract and mouth of 40–60% of healthy adults.

While often benign, C. albicans can cause infections, known as candidiasis, if the opportunity arises. This transition from a harmless resident to a pathogen occurs when the body’s internal balance is disrupted, allowing the fungus to overgrow.

C. albicans in the Human Body

As a member of the human microbiota, C. albicans resides on various mucosal surfaces. The most common sites for colonization include the gastrointestinal tract, the genitourinary tract, and the skin. In these locations, the yeast population is kept in check by two primary factors.

The host’s immune system constantly monitors microbial populations. Competition with other microorganisms for nutrients and space also prevents C. albicans from proliferating to the point of causing an infection.

Triggers for C. albicans Overgrowth

Candida albicans is an opportunistic pathogen, meaning it takes advantage of situations where the body’s defenses are weakened. Several factors can create this opportunity for overgrowth. A primary trigger is a compromised immune system, such as in individuals with HIV/AIDS or those undergoing chemotherapy.

The use of broad-spectrum antibiotics is another factor, as these medications can kill beneficial bacteria that compete with C. albicans. Hormonal fluctuations, such as those during pregnancy or from oral contraceptive use, can alter the vaginal environment and make it more favorable for yeast growth. Underlying health conditions like diabetes also contribute by providing higher sugar levels, which serve as a food source for the yeast.

In response to these shifts, C. albicans can change its form to a filamentous structure called a hypha. This change enables the fungus to become more invasive and penetrate tissues, allowing it to cause disease.

Candidiasis: Infections Caused by C. albicans

When C. albicans overgrowth occurs, it results in an infection known as candidiasis. The name and symptoms depend on the location of the infection, which can range from mild to serious.

Common forms of candidiasis include:

• Oropharyngeal candidiasis (oral thrush), which manifests as white patches on the tongue and inner mouth, often with soreness. It is frequently seen in infants and adults with weakened immune systems.
• Vulvovaginal candidiasis (vaginal yeast infection), which causes intense itching, irritation, and a thick, white vaginal discharge.
• Cutaneous candidiasis, a skin infection that develops in warm, moist areas like skin folds, causing a red, itchy rash. Diaper rash in infants can also be caused by C. albicans.
• Invasive candidiasis, a severe form where the fungus enters the bloodstream (candidemia) and spreads to organs like the heart, brain, and kidneys. This affects severely immunocompromised or hospitalized individuals.

Addressing C. albicans Infections

Managing C. albicans infections focuses on controlling the fungal overgrowth and restoring the body’s microbial balance. Treatment primarily involves antifungal medications that target fungal cells. The type of medication and its delivery method depend on the infection’s location and severity.

Superficial infections like oral thrush or skin rashes are treated with topical creams or mouthwashes, while vaginal yeast infections are treated with suppositories or creams. Widespread infections may require oral antifungal pills, and severe invasive candidiasis requires intravenous (IV) antifungals in a hospital. Seeking a medical diagnosis is necessary to ensure correct treatment.

Beyond medication, managing underlying triggers is part of the approach. This includes controlling blood sugar levels in diabetics or reviewing medications with a healthcare provider.