candidiasis

Candidiasis is an infection caused by fungi of the genus Candida, most often Candida albicans. It ranges from superficial mucocutaneous disease to invasive infections. Candida species are part of the normal microbiota of the mouth, gut, and vagina, and disease usually results from overgrowth or invasion when host defenses are reduced or microbial balance is disrupted.

Mucocutaneous forms include oral candidiasis (thrush), vaginal candidiasis, and cutaneous intertrigo. Oral thrush presents as creamy white plaques on the tongue or inside the cheeks with soreness. Vaginal candidiasis causes itching and discharge. Cutaneous candidiasis affects skin folds with redness and cracking. In immunocompromised individuals, disease can be more extensive, and esophageal candidiasis may occur.

Invasive candidiasis involves the bloodstream or internal organs and occurs mainly in hospitalized or immunocompromised patients. Risk factors include central venous catheters, broad-spectrum antibiotics, surgery, neutropenia, diabetes, and critical illness. Candida species such as Candida auris can cause outbreaks and exhibit antifungal resistance.

Diagnosis combines clinical assessment with laboratory tests. Microscopy and culture from affected sites confirm disease; blood cultures detect candidemia. Nonculture tests, including beta-D-glucan assays and PCR, support diagnosis in suspected invasive disease.

Treatment depends on location and severity. Superficial infections use topical antifungals (clotrimazole, miconazole, nystatin) or short courses of oral azoles. Invasive candidiasis and esophageal involvement require systemic therapy, typically an echinocandin (caspofungin, micafungin, anidulafungin), followed by fluconazole if susceptible; amphotericin B may be used in resistant cases. Preventive measures include careful device management and antimicrobial stewardship.