What is the diagnosis and treatment for multiple painful yellowish plaques in the oral cavity?

Multiple Painful Yellowish Plaques in the Oral Cavity

Multiple painful yellowish plaques in the oral cavity with pseudomembrane formation require urgent systematic evaluation to rule out life-threatening conditions including hematologic malignancies, invasive fungal infections, and severe systemic diseases before considering benign causes.

Immediate Diagnostic Approach

The 2022 International Journal of Oral Science expert consensus provides a structured algorithm for evaluating difficult oral ulcerations with yellowish-white pseudomembranes 1.

Initial Blood Work (Before Biopsy)

Obtain these tests immediately to identify potentially fatal conditions:

• Full blood count - Critical to rule out acute leukemia (neutropenia <2.0% can present with yellowish pseudomembrane-covered necrotic ulcers) 1
• Fasting blood glucose - Hyperglycemia is a major predisposing factor for invasive fungal infections presenting as yellowish plaques 1
• Blood coagulation studies - Required before biopsy 1
• HIV antibody and syphilis serology - Essential screening 1
• Fungal markers (1-3-β-D-glucan and galactomannan) - If diabetes or immunosuppression present, as invasive fungal infections can present with yellowish pseudomembranes 1

Key Differential Diagnoses by Clinical Context

Life-threatening conditions that present with yellowish plaques/pseudomembranes:

1. Acute leukemia - Widespread necrotic ulcers with smooth, thick yellowish-white pseudomembrane, particularly with neutropenia 1

2. Extranodal NK/T-cell lymphoma - Serious erosion and necrosis covered by yellowish-white pseudomembrane, typically lasting weeks to months 1

3. Invasive fungal infection - In diabetic or immunosuppressed patients, presents with yellowish plaques; elevated fungal markers confirm diagnosis 1

4. Oral tuberculosis - Widespread ulcers and masses with yellowish covering; requires acid-fast bacilli staining and chest imaging 1

Common benign conditions:

1. Crohn's disease - Ulcers with yellowish-white pseudomembrane, often with concurrent abdominal symptoms 1

2. Candidiasis - Yellowish plaques that can be scraped off, common in diabetics 2

Treatment Algorithm Based on Diagnosis

If Fungal Infection Suspected (Diabetic/Immunosuppressed Patient)

First-line antifungal therapy:

• Nystatin oral suspension (100,000 units) four times daily for 1 week, OR 3
• Miconazole oral gel 5-10 mL held in mouth after food four times daily for 1 week 3
• Fluconazole 200 mg on first day, then 100 mg once daily for oropharyngeal candidiasis 4

For invasive fungal infection (elevated fungal markers):

• Caspofungin infusion (hospital setting) 1

Pain Management Protocol

Immediate pain relief (use while awaiting diagnosis):

• Viscous lidocaine 2% - 15 mL per application, held in mouth for 1-2 minutes before spitting out 3, 5
• Benzydamine hydrochloride rinses - Every 3 hours, particularly before eating 3, 5
• Avoid eating/drinking for 30 minutes after application 3

Supportive care:

• Alcohol-free mouthwash - Rinse 4 times daily for 1 minute with 15 mL 1
• Soft toothbrush after meals and before sleep 1, 5
• Avoid irritants - No smoking, alcohol, spicy foods, citrus fruits, hot drinks, or crusty foods 1, 6
• White soft paraffin to lips every 2 hours 3

When to Proceed to Biopsy

Biopsy is indicated if:

• Blood work shows no diagnostic abnormalities 1
• No contraindications identified 1
• Multiple sites with different morphology require multiple biopsies 1

Critical pitfall: If initial biopsy shows only "inflammatory ulcer with lymphocyte infiltration," this is non-specific and requires consultation with superior pathologists 1. Consider special stains (acid-fast bacilli for tuberculosis, immunohistochemistry for lymphoma) 1.

If Diagnosis Remains Unclear After Initial Workup

Proceed to Part 3 evaluation:

• Detailed history for systemic diseases (tuberculosis, inflammatory bowel disease, autoimmune conditions) 1
• Colonoscopy if abdominal symptoms present (Crohn's disease) 1
• Chest imaging if tuberculosis suspected 1
• Metagenomic sequencing or tissue culture 1
• Trial of low-dose short-term oral glucocorticoids (diagnostic treatment) 1
• Multi-disciplinary team consultation 1

Common Pitfalls to Avoid

• Never dismiss yellowish plaques as simple aphthous ulcers - They can represent acute leukemia or lymphoma 1
• Always check complete blood count first - Neutropenia with oral lesions is a medical emergency 1
• Don't overlook diabetes screening - Uncontrolled hyperglycemia predisposes to life-threatening invasive fungal infections 1
• Avoid petroleum jelly chronically on oral mucosa - It promotes dehydration and infection risk 1