Infectious Disease · Fungal Infections
The facts most likely to be tested
Oral candidiasis presents as creamy white plaques on the buccal mucosa, palate, or tongue that are easily scraped off with a tongue depressor.
The underlying base of the lesion after scraping is typically erythematous and may exhibit punctate bleeding.
The causative organism is the dimorphic fungus Candida albicans, which is a normal commensal of the human oral flora.
Diagnosis is primarily clinical, but a KOH preparation showing pseudohyphae and yeast cells confirms the presence of the fungus.
New-onset oral candidiasis in an otherwise healthy adult should prompt screening for HIV infection or diabetes mellitus.
First-line treatment for mild oropharyngeal disease is topical nystatin suspension or clotrimazole troches.
Systemic therapy with oral fluconazole is indicated for moderate-to-severe cases or patients who are immunocompromised.
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A 34-year-old male presents to the clinic complaining of a persistent 'fuzzy' sensation in his mouth for the past two weeks. He reports no pain but notes difficulty swallowing. Physical examination reveals creamy white, curd-like plaques on the dorsal surface of the tongue and buccal mucosa. The plaques are easily scraped off with a tongue depressor, leaving an erythematous, bleeding base. The patient has no significant past medical history but admits to recent unprotected sexual encounters.
What is the most appropriate next step in the management of this patient?
HIV testing
The patient presents with classic oral candidiasis; in a young, healthy adult without a history of antibiotic or steroid use, the most important next step is to screen for underlying immunosuppression, specifically HIV.
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High yield triage
Etiology / Epidemiology
Opportunistic infection by Candida albicans. Immunocompromised states, inhaled corticosteroids, and broad-spectrum antibiotics are primary drivers.
Clinical Manifestations
Presents as pseudomembranous white plaques that scrape off with an erythematous base. Angular cheilitis is a common associated finding.
Diagnosis
Clinical diagnosis is standard; KOH preparation showing yeast and pseudohyphae confirms if uncertain.
Treatment
Nystatin swish and swallow is first-line for mild cases; Fluconazole is the systemic agent of choice.
Prognosis
Generally self-limiting with treatment; esophageal involvement indicates severe immunosuppression or HIV/AIDS.
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Epidemiology & Etiology
Common in neonates, the elderly, and patients using inhaled corticosteroids without spacer devices. Significant risk factor includes HIV/AIDS (CD4 < 200) and recent broad-spectrum antibiotic use. It is an opportunistic fungal infection caused by Candida albicans.
Pertinent Anatomy
Infection typically involves the buccal mucosa, tongue, and palate. Angular cheilitis involves the commissures of the lips. Esophageal extension is a defining feature of AIDS-defining illness.
Pathophysiology
Disruption of the oral microbiome or host immune surveillance allows overgrowth of commensal Candida. Hyphal invasion of the superficial epithelium triggers an inflammatory response. Chronic irritation or local immunosuppression facilitates the transition from colonization to symptomatic infection.
Clinical Manifestations
Classic thrush presents as white, curd-like plaques that scrape off to reveal a raw, bleeding base. Red flag: odynophagia or dysphagia suggests esophageal candidiasis, requiring systemic therapy. Angular cheilitis manifests as painful fissures at the corners of the mouth.
Diagnosis
Diagnosis is primarily clinical. If diagnostic uncertainty exists, a KOH preparation of a scraping reveals yeast and pseudohyphae. A biopsy is reserved for refractory cases to rule out malignancy or other infections.
Treatment
Mild cases are treated with Nystatin swish and swallow suspension. Moderate to severe or refractory cases require oral Fluconazole. Contraindications: Avoid systemic azoles in pregnancy due to potential teratogenicity. Ensure patients rinse mouth after using steroid inhalers to prevent recurrence.
Prognosis
Excellent with appropriate antifungal therapy. Recurrence is common if the underlying immunodeficiency or corticosteroid use is not addressed. Esophageal involvement requires systemic treatment and evaluation for HIV.
Differential Diagnosis
Oral Leukoplakia: white patches that do not scrape off
Oral Lichen Planus: Wickham striae (lacy white lines)
Diphtheria: gray pseudomembrane that bleeds when scraped
Geographic Tongue: migratory erythematous patches
Herpetic Stomatitis: painful vesicles and ulcers