Recurrent aphthous stomatitis — SAQ

Stem

A 24-year-old woman presents with recurrent painful mouth ulcers for 18 months. They occur every 6-8 weeks, are on the buccal mucosa and ventral tongue, have a yellow-white base and red halo, and usually heal in 10 days without scarring. She has no preceding vesicles. She has no genital ulcers, eye symptoms or gastrointestinal symptoms.

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Questions

a) What is the most likely diagnosis and what clinical features support it? (2 marks)

b) List important differential diagnoses and distinguishing features. (3 marks)

c) What investigations would you arrange if the ulcers become frequent, severe or atypical? (2 marks)

d) Outline stepwise management. (3 marks)

Model answer

a) Diagnosis (2 marks)

• Recurrent aphthous stomatitis, most likely minor aphthae. (1)
• Supporting features: recurrent painful shallow ulcers, yellow-white fibrinous base, erythematous halo, non-keratinized mucosa, no vesicular stage, healing within 7-14 days without scarring. (1)

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^[2]b) Differential diagnosis (3 marks)

• HSV: vesicles first, often keratinized mucosa such as hard palate or gingiva; confirm with HSV PCR if uncertain. (0.5)
• Hand-foot-mouth disease: febrile child or outbreak, oral ulcers plus palms/soles/buttocks rash. (0.5)
• Traumatic ulcer: single ulcer at bite line, sharp tooth, denture or orthodontic contact. (0.5)
• Oral squamous cell carcinoma: persistent ulcer beyond 2-3 weeks, induration, rolled edge, bleeding, neck node, tobacco/alcohol/betel risk; biopsy/referral. (0.5)
• Erosive lichen planus: Wickham striae with chronic erosions. (0.5)
• Pemphigus or pemphigoid: widespread fragile erosions or desquamative gingivitis; biopsy and direct immunofluorescence. (0.5)

^[3]c) Investigations if recurrent, severe or atypical (2 marks)

• FBC with differential, ferritin/iron studies, vitamin B12, folate and zinc. (1)
• Directed tests: coeliac serology with total IgA if iron deficiency or GI features; HIV Ag/Ab if severe, atypical or risk factors; ESR/CRP/faecal calprotectin or gastroenterology referral for IBD symptoms; serial FBC if periodic fever/infections suggest cyclic neutropenia; biopsy for persistent or suspicious ulcer. (1)

d) Management (3 marks)

• Mild measures: explanation, soft toothbrush, remove trauma, SLS-free toothpaste trial, avoid reproducible food triggers, chlorhexidine mouthwash, topical benzydamine or lidocaine for pain. (0.75)
• First-line pharmacological therapy for frequent painful disease: topical corticosteroids such as triamcinolone dental paste or betamethasone rinse, started early and used as rinse-and-spit where appropriate. (1)
• Treat causes and associations: replace iron, B12, folate or zinc if deficient; investigate/manage coeliac disease, IBD, HIV, Behçet disease or neutropenia when suspected. (0.75)
• Refer/escalate: oral medicine/dermatology/ENT/maxillofacial for major, complex, treatment-resistant or suspicious ulcers; systemic agents such as colchicine, dapsone or thalidomide only under specialist supervision. (0.5)

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Examiner traps

• Herpetiform aphthae are not HSV.
• Any non-healing indurated ulcer needs biopsy pathway assessment, not repeated steroid paste.
• Oral aphthae plus genital ulcers or uveitis is Behçet disease until assessed.

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References4ShowHide

1. [1]Oral Aphthous: Pathophysiology, Clinical Aspects and Medical Treatment. Archives of Razi Institute, 2021.PMID 35355774
2. [2]Recurrent aphthous ulceration: a review of potential causes and novel treatments. The Journal of dermatological treatment, 2018.PMID 29278022
3. [3]Jacobson JM, Greenspan JS, Spritzler J, et al. Thalidomide for the treatment of oral aphthous ulcers in patients with human immunodeficiency virus infection. National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group N Engl J Med, 1997.PMID 9154767
4. [4]Lin D, Yang L, Wen L, et al. Crosstalk between the oral microbiota, mucosal immunity, and the epithelial barrier regulates oral mucosal disease pathogenesis Mucosal Immunol, 2021.PMID 34040155