What is the next step in managing a 10-month-old infant with normal neurology examination, increased irritability, crying while holding the back of their head, and white patches over the peri-oral region, suggestive of oral candidiasis (thrush)?

Management of 10-Month-Old with Oral Thrush and Irritability

Treat the oral candidiasis with nystatin oral suspension 200,000 units (2 mL) four times daily for 7-14 days, but the key next step is to evaluate for potential invasive candidiasis given the concerning symptom of irritability with head-holding behavior in this infant. 1, 2, 3

Immediate Assessment Required

The combination of oral thrush with increased irritability and crying while holding the back of the head raises concern for possible CNS involvement, which can occur with disseminated candidiasis in infants. 1

Critical evaluation steps:

• Perform a lumbar puncture to rule out Candida meningitis, as CNS involvement should be assumed in infants with candidemia and can present as meningoencephalitis 1
• Obtain blood cultures to assess for candidemia, as failure to identify invasive disease places the infant at risk for prolonged infection and irreversible neurodevelopmental impairment 1
• Perform dilated retinal examination to evaluate for Candida endophthalmitis, which is recommended for all infants with suspected invasive candidiasis 1

Treatment of Oral Candidiasis

If invasive disease is ruled out, proceed with standard oral thrush treatment:

First-Line Therapy

• Nystatin oral suspension (100,000 IU/mL): 2 mL (200,000 units) four times daily for 7-14 days 2, 3
• Use dropper to place one-half of dose in each side of mouth 3
• Avoid feeding for 5-10 minutes after administration 3
• Continue treatment for at least 48 hours after symptoms disappear and cultures confirm eradication 3

Alternative Options if Nystatin Fails

• Fluconazole oral: 3-6 mg/kg daily for 7 days is the preferred second-line agent with superior efficacy 2
• Miconazole oral gel 15 mg every 8 hours has higher cure rates (85.1% vs 42.8-48.5% for nystatin) but raises concerns about generating triazole resistance 2, 4

If Invasive Candidiasis is Confirmed

Escalate immediately to systemic antifungal therapy:

• Amphotericin B deoxycholate 1 mg/kg daily IV for at least 3 weeks 1
• Alternative: Fluconazole 12 mg/kg daily IV/oral 1
• Duration of at least 3 weeks, with longer treatment if CNS involvement confirmed 1
• Remove any central venous catheters if present, as failure to do so increases mortality and neurodevelopmental impairment risk 1

Critical Pitfalls to Avoid

• Do not dismiss irritability and head-holding as normal infant fussiness when oral thrush is present—this combination warrants investigation for invasive disease 1
• Do not treat with topical therapy alone if any systemic symptoms are present 1
• Do not discontinue therapy when symptoms improve but before completing the full 7-14 day course, as premature discontinuation leads to high recurrence rates 2, 4
• Never use combination antifungal/corticosteroid preparations in infants 4, 5

Additional Management Considerations

If breastfeeding:

• Treat mother and infant simultaneously 2, 4
• Mother should apply miconazole cream to nipples/areola after each feeding 2, 4

Environmental measures:

• Sterilize all items contacting the mouth (pacifiers, bottles, toys) during and after treatment 4
• Evaluate and treat maternal vaginal candidiasis if present 4, 5

Follow-Up

• Neurologic impairment is common in survivors of neonatal invasive candidiasis, therefore careful follow-up of neurodevelopmental parameters is essential if invasive disease is identified 1
• Clinical improvement should be evident within 48-72 hours for uncomplicated oral thrush 4
• The endpoint should be mycological cure, not just clinical improvement 2, 4