Glossitis

Anatomy of the Tongue

• Embryology: Derived from the median lingual swelling on the mandibular arch.
• Structure: Comprised of skeletal muscle; motor innervation via hypoglossal nerve (except palatoglossus by vagus nerve); sensory innervation from the lingual nerve (anterior two-thirds) and accessory nerve (posterior one-third).
• Surface: Divided by median sulcus; contains papillae (filiform, fungiform, and pointed filiform) and lymphoid tissue (lingual tonsils).

Etiology of Glossitis

1. Anemia:
   • Iron-deficiency anemia
   • Pernicious anemia
2. Vitamin B Deficiencies:
   • B1, B2, B3, B6, B9, B12
3. Infections:
   • Viral: Herpes viruses
   • Bacterial: Rare in immunocompetent patients
   • Fungal: Candida species
   • Parasites: Malaria, spirochetes
4. Medications:
   • ACE inhibitors, albuterol
   • Organosulfur antimicrobials
   • Oral contraceptives
   • Lithium carbonate
5. Others:
   • Psychological factors, irritants (alcohol, spicy food, tobacco), familial variants, mechanical irritation, poor hydration, Down syndrome, psoriasis, burning mouth syndrome

Epidemiology

• Diverse causes; variable prevalence
• Geographic tongue prevalence: 1.41% to 2.29%
• Median rhomboid glossitis prevalence: 0.30% to 0.46%

Pathophysiology

• Poorly understood for some types (e.g., geographic tongue)
• Stress and dietary factors can exacerbate conditions like geographic tongue

History and Physical Examination

• History: Nutritional status, dietary restrictions, substance use, medical history, medication review, and family history
• Physical Exam: Appearance of tongue surface, mucosa character, dental health, lymphadenopathy

Types of Glossitis

• Atrophic Glossitis: Erythematous, smooth, shiny, dry appearance
• Median Rhomboid Glossitis: Central rhomboid hyperkeratotic areas
• Benign Migratory Glossitis: Smooth areas with loss of papillae, white border
• Geometric Glossitis: Painful linear fissures
• Strawberry Tongue: Red, denuded appearance, hypertrophic fungiform papillae

Evaluation

• Biopsy: For bullous diseases or suspicious lesions
• Laboratory Studies: Vitamin levels, rheumatologic tests, CBC, HIV testing, endocrine studies
• Imaging: Only for suspected malignancy (CT neck with IV contrast)

Treatment/Management

• Atrophic Glossitis: Vitamin B12 injections
• Median Rhomboid Glossitis: Antifungals if symptomatic
• Benign Migratory Glossitis: Reassurance, mouth rinses
• Geometric Glossitis: Reassurance, antivirals for acute episodes
• Strawberry Tongue: Vitamin B12 supplementation
• Medication-Induced: Discontinue offending medication
• Infectious: Treat underlying infection, manage immunosuppression

Differential Diagnosis

• Normal-Appearing Tongue: Burning mouth syndrome, diabetic neuropathy, acid reflux
• Atrophic Glossitis: Protein-calorie malnutrition, vitamin B12 deficiency, candidiasis
• Median Rhomboid Glossitis: Haemangioma, amyloidosis, squamous cell carcinoma
• Strawberry Tongue: Yellow fever, Kawasaki disease, toxic shock syndrome
• Geographic Tongue: Oral lichen planus, dehydration, leukoplakia

Prognosis

• Varies by cause; generally benign but can be chronic or lifelong
• Many causes reversible with treatment of underlying condition

Complications

• Anxiety due to appearance; biopsy may reassure patient and provider

Patient Education and Deterrence

• Educate about benign nature
• Symptomatic treatment with mouth rinses
• Biopsy chronic or unchanging lesions to rule out malignancy
• Emphasize good oral hygiene