What is the cause of a dried-out edge of the tongue and a tingly sensation in a patient?

Dried-Out Edge of Tongue with Tingling: Differential Diagnosis and Management

The combination of a dried-out tongue edge with tingling sensation requires urgent evaluation to exclude malignancy, particularly in patients over 40 with tobacco/alcohol use, followed by assessment for neuropathic conditions (burning mouth syndrome, post-traumatic trigeminal neuropathy), systemic causes (nutritional deficiencies, diabetes), and Sjögren's syndrome. 1

Immediate Red Flag Assessment

Malignancy must be ruled out first when tongue symptoms are accompanied by: 1

• New numbness in the oral cavity or cheek with intraoral swelling or ulceration 2, 1
• Unilateral symptoms with induration or non-healing lesions 1
• Palpable neck mass or lymphadenopathy 2
• Patient age >40 years with tobacco or alcohol use 2, 1
• Limited tongue mobility suggesting muscle or nerve invasion 2

Physical examination priorities include: 2

• Removal of dentures to inspect all oral surfaces 2
• Palpation of the floor of mouth to identify ulcers or masses 2
• Using gauze to grasp the tongue to facilitate inspection of lateral aspects 2
• Assessment for tonsil asymmetry or masses 2
• Neck palpation for masses and lymphadenopathy 2

Neuropathic Pain Conditions

Post-traumatic trigeminal neuropathy develops within 3-6 months following dental procedures or facial trauma, presenting as continuous burning and tingling sensations. 1 This requires documentation of recent dental work or facial trauma history. 1

Burning mouth syndrome (BMS) commonly affects the tongue tip bilaterally, characterized by burning, stinging, or tingling sensations with normal-appearing oral mucosa. 1, 3 BMS predominantly affects peri- and post-menopausal women and is associated with dry mouth and abnormal taste. 3, 4

Salivary Gland Dysfunction and Sjögren's Syndrome

Baseline evaluation of salivary gland function is essential before initiating treatment for oral dryness, as subjective feelings often do not match objective measurements. 2 Measure whole salivary flows and consider salivary scintigraphy. 2

Xerostomia (dry mouth) in older adults results from lower salivary flow rates with aging, exacerbated by medications. 2 This can present as dried-out tongue edges with associated tingling from mucosal irritation. 2

Systematic Diagnostic Workup

For acute unilateral tongue symptoms: 1

• Assess for recent dental procedures or oral trauma 1
• Examine for visible mucosal lesions, ulcerations, or masses 1
• Palpate the floor of mouth and submandibular area for stones or masses 1

For chronic bilateral burning or numbness, obtain laboratory testing: 1, 3

• Complete blood count (CBC) with differential 1, 3
• Iron studies and vitamin B12 level 1, 3, 5
• Fasting glucose and HbA1c 1, 3
• Vitamin D 25(OH) level 1, 3
• Thyroid function tests (TSH, free T4) 1, 3

Exclude secondary causes including: 3

• Candidiasis (perform scraping and microscopic examination with KOH preparation) 3, 6
• Nutritional deficiencies (particularly vitamin B12, iron, folic acid) 1, 5
• Medication side-effects 3

Management Based on Etiology

For salivary gland dysfunction with mild dysfunction: 2

• Non-pharmacological glandular stimulation using sugar-free acidic candies, lozenges, xylitol, or sugar-free chewing gum 2

For moderate glandular dysfunction: 2

• Consider pharmacological stimulation with muscarinic agonists (pilocarpine or cevimeline) 2
• Note the high frequency of adverse events with these medications 2

For no salivary output: 2

• Saliva substitution with oral sprays, gels, and rinses containing neutral pH, fluoride, and electrolytes 2

For primary burning mouth syndrome: 3

• Reassurance and education 3
• Cognitive behavioral therapy (CBT) 3
• Pharmacologic options: gabapentin, alpha-lipoic acid, topical clonazepam or diazepam 3, 7

For secondary causes: 3

• Address nutritional deficiencies with appropriate supplementation 3, 5
• Manage diabetes and control thyroid dysfunction 3
• Discontinue offending medications 3
• Treat candidiasis with antifungal therapy 3, 6

Critical Pitfalls to Avoid

Do not dismiss unilateral symptoms as benign without thorough evaluation, as these may indicate malignancy requiring urgent referral. 1 A nontender neck mass is more suspicious for malignancy than a tender mass. 2

Do not rely solely on subjective symptoms when evaluating oral dryness; objective measurement of salivary gland function is essential. 2

Do not overlook vitamin B12 deficiency, which can present with atrophic glossitis and glossodynia that may be misdiagnosed as primary burning mouth disorder. 5 The tongue may appear beefy, red, and smooth. 5