• Clinical science

Candidiasis

Summary

Candida albicans is the most common cause of candidiasis and appears almost universally in low numbers on healthy skin, in the oropharyngeal cavity, and in the gastrointestinal and genitourinary tracts. In immunocompetent individuals, C. albicans usually causes minor localized infections, including thrush (affecting the oral cavity), vaginal yeast infections (if there is an underlying pH imbalance), and infections of the intertriginous areas of skin (e.g., the axillae or gluteal folds). More widespread and systemic infections may occur in immunocompromised individuals (e.g., neonates, diabetics, and HIV patients), with the esophagus most commonly affected (candida esophagitis). Localized cutaneous candidiasis may be treated with topical antifungal agents (e.g., clotrimazole). More widespread and systemic infections require systemic therapy with fluconazole or caspofungin.

Etiology

Pathogen

Risk factors

C. albicans appears almost universally in low numbers on healthy adults but can cause disease in certain high-risk patients, especially those that are immunocompromised.

References:[2][3][4][5][6][7]

Pathophysiology

  • Local infection: imbalance in local flora (e.g., triggered by antibiotic use) → local overgrowth of C. albicans local mucocutaneous infection (e.g., oropharyngeal infection, vaginitis)
  • Systemic infection: local mucocutaneous infection → breach of skin/mucosal barrier or translocation (IV catheterization, ascending infection in pyelonephritis, or resorption via GIT) → direct invasion of bloodstream (candidemia) → spread to visceral tissues → disseminated organ infection (e.g., pyelonephritis, endocarditis)

References:[2][8][9][10]

Clinical features

Local mucocutaneous

Systemic candidiasis

References:[2][12][8][13][14][15]

Diagnostics

A suspected diagnosis based on clinical appearance requires confirmation with additional tests.

References:[16]

Treatment

Treatment of local mucocutaneous infection

Treatment of systemic infection

  • Indications: systemic treatment is preferred in the following
  • Drug of choice: IV caspofungin; or micafungin (echinocandins) for 2 weeks after resolution of symptoms and documented clearance of C. albicans
  • Alternatives
    • Fluconazole: in patients that are not critically ill and in the case that resistance is unlikely
    • Amphotericin B: because of toxicity, only indicated if there is intolerance, limited availability, or resistance to alternatives

References:[2][15][16][17][18][19]