Oral Thrush

Oral thrush is Candida infection of the oral mucosa, most commonly caused by Candida albicans. It is common in young infants because of immature mucosal immunity and may also occur after antibiotic exposure, inhaled corticosteroid use, immunosuppression or significant malnutrition.

Persistent, recurrent or unusually severe candidiasis should trigger assessment for an underlying immune disorder, HIV infection, diabetes or other predisposing disease.

Typical findings are:

• White or creamy plaques on the tongue, buccal mucosa, palate or gingiva
• Plaques that are adherent and may leave an erythematous or slightly bleeding surface when removed
• Irritability during feeding
• Reduced feeding in more extensive disease
• Associated candidal diaper dermatitis

Milk residue usually wipes away easily and does not produce an inflamed underlying mucosa.

Diagnosis is usually clinical.

Microscopy or fungal culture is unnecessary in straightforward disease but may be useful when:

• Treatment fails
• Disease is recurrent
• The diagnosis is uncertain
• Resistant Candida is suspected

Assess for contributing factors including recent antibiotics, inhaled corticosteroid use, immunosuppression and poor nutritional status.

• Nystatin oral suspension 100,000 units/mL: commonly 1 mL PO four times daily in infants, distributed around the oral mucosa after feeds. Continue for at least 48 hours after lesions resolve, commonly 7 to 14 days in total.

• Oral miconazole gel is effective in older infants and children where age appropriate, but requires caution in very young infants because of choking risk and important drug interactions.

• Treat concurrent maternal nipple candidiasis where breastfeeding related reinfection is suspected.

• Sterilize or thoroughly clean feeding equipment and pacifiers.

• Rinse the mouth after inhaled corticosteroids and use a spacer where appropriate.

Persistent disease despite correct therapy requires reconsideration of diagnosis and immune status.