Introduction
Oral Thrush (Candidiasis) is a clinical infection of mucous membranes due to the fungus species Candida.
Candida albicans is the most frequently isolated strain.
Classification of oral thrush
- Acute oral candidasis
- Chronic oral candidasis
- Denture association candidasis/ denture stomatitis
Pathogenesis of oral thrush
- Immunosupression results in the Candida albicans (a normal oral commensal) becoming virulent
- It invades and proliferates in superficial epithelium
- Results in a thick plaque which is oedematous and not easily rubbed off
Symptoms and clinical features of oral thrush
- A creamy/whitish, soft and friable slough located on the soft tissues of the oral cavity: tongue, palate, cheek, pharynx
- May be asymptomatic, or painful, with difficulty in swallowing
Predisposing factors
- Denture wearing
- Reduced salivation (e.g. drug induced)
- Antibiotic therapy (especially broad spectrum)
- Poorly controlled diabetes mellitus
- Steroid therapy (chronic)
- Salivary gland damage (e.g. post radiation)
- Malnutrition
- HIV infection
- Leukaemia
- Iron, vitamin B, folic acid deficiency and
- Agranulocytosis
Investigations
- Smear of the affected region and Gram staining or PAS with or without potassiumvhydroxide to demonstrate hyphae
- Swab sample for microscopy, culture and sensitivity
- Biopsy and histopathologic examination
- Identify predisposing factors (including immunosuppresion)
- Define extent of involvement
Treatment for Oral Thrush
Non-drug treatment
- Manage any underlying predisposing factors
- Replace worn dentures
- Proper counselling of patients as to use of dentures
- Diet modification and improvement
- Chlorhexidine mouthwash three times daily for 1-2 weeks
Drug treatment
A. Topical anti-fungal medication:
i. Nystatin suspension
- Adult: 100,000 units/mL 4 times daily, after food (usually for 7 days). Continue for 48 hours after lesions have resolved
- Child
- 1 month 18 years, prophylaxis and treatment: 100,000 units 6 hourly after food for 7 days. Continue for 48 hours after lesions have healed
- Immunocompromised children: 500,000 units 6 hourly for 7 days
Or:
ii. Miconazole oral gel 2%
Adult: place 5-10 mL in the mouth after food and retain near lesions 4 times daily
Child
- under 2 years: 2.5 mL twice daily;
- 2 – 6: years: 5 mL twice daily;
- 6 – 12 years: 5 mL 4 times daily;
- 12-18 years: 5-10mL. 4 times daily.
- Leave in the mouth after food and retain near lesions.
B. Systemic antifungal drugs
Some patients may require systemic
antimicrobial medicines
i. Fluconazole
Adult: 50 mg orally daily for 7-14 days
Child: 3-6mg/kg on the first day, then 3mg/kg daily
- For neonates up to 2 weeks old: administer every 72 hours;
- 2 – 4 weeks old: administer every 48 hours