What is the clinical significance of median rhomboid glossitis in an otherwise healthy adult and what are the recommended management and follow‑up?

Median Rhomboid Glossitis: Clinical Significance and Management

Median rhomboid glossitis (MRG) is a benign condition with minimal clinical significance in otherwise healthy adults that requires no treatment unless symptomatic, though it warrants evaluation for underlying candidal infection and, in rare cases, exclusion of malignancy.

Clinical Significance

MRG represents a benign lesion with no malignant potential in the vast majority of cases. The condition presents as a smooth, red, oval or rhomboid patch on the dorsal midline of the tongue, typically anterior to the lingual "V" 1, 2. While historically considered a developmental anomaly from failure of the tuberculum impar to be covered by lateral tongue processes, current evidence strongly supports a candidal etiology (erythematous candidiasis) rather than a true developmental defect 3, 4.

Key Clinical Features to Document:

• Location: Typically midline dorsum of tongue, though paramedial variants occur 5
• Appearance: Depapillated, flat maculate or raised 2-5mm, reddish rhomboid area 5
• Symptoms: Usually painless; occasional mild itching or irritation 2
• Demographics: More common in males 2

Important Associations:

Candida albicans infection is the primary pathogenic factor, inducing pseudoepitheliomatous hyperplasia and inflammatory changes 4. In immunocompromised patients, particularly those with HIV, MRG represents a distinct form of oral candidiasis and may indicate immune dysfunction 3. In HIV-positive patients, MRG was found in 18% of cases with average CD4+ counts of 397.5/mm³ 3.

Risk factors to assess include:

• Tobacco smoking 4
• Denture wearing 4
• Immunocompromised status, particularly HIV infection 3

Differential Diagnosis to Exclude

Critical pitfall: Do not assume all midline tongue lesions are benign MRG. The following must be considered and ruled out based on clinical and histopathological findings when presentation is atypical 5:

• Squamous cell carcinoma (most important to exclude)
• Hemangioma
• Pyogenic granuloma
• Amyloidosis
• Granular cell tumor

Recommended Management Algorithm

For Asymptomatic, Classic Presentation:

1. Patient education only - Reassure regarding benign nature 1, 2
2. No active treatment required 1, 2
3. Counsel on risk factor modification: smoking cessation, proper denture hygiene 4

For Symptomatic Cases or Suspected Candidal Infection:

1. Trial of antifungal therapy - Topical or systemic antifungals targeting Candida albicans 3, 4
2. Reassess after 2-4 weeks of antifungal treatment
3. If lesion resolves with antifungal therapy, this confirms candidal etiology and no further workup needed 4

For Atypical Presentations Requiring Biopsy:

Indications for histopathological examination 5:

• Paramedial or unusual location
• Irregular borders or rapid growth
• Ulceration or bleeding
• Failure to respond to antifungal therapy
• Patient age and risk factors concerning for malignancy

Follow-Up Recommendations

For typical, asymptomatic MRG: No routine follow-up required beyond standard dental examinations 1, 2

For immunocompromised patients: Consider MRG as a marker of oral candidiasis and assess immune status, particularly CD4+ counts in HIV-positive patients 3

For treated symptomatic cases: Re-evaluate at 2-4 weeks post-antifungal therapy to confirm resolution 4

Common Pitfalls to Avoid

• Do not perform unnecessary biopsies on classic, asymptomatic midline lesions in healthy adults 1, 2
• Do not dismiss paramedial tongue lesions as typical MRG without careful evaluation, as location variants exist but warrant closer scrutiny 5
• Do not overlook immunocompromised status, particularly HIV infection, as MRG may be an early oral manifestation 3
• Do not ignore persistent lesions that fail to respond to antifungal therapy - these require biopsy to exclude malignancy 5