Patients presenting with desquamative gingivitis (DG) are typically some of the most frustrated, aggravated patients I encounter. Frequently, they have not been adequately evaluated, are in pain, and are desperate for help.
The differential diagnosis is broad – it is essential to know their overall health, what medications they are taking, and if there is involvement of other mucous membranes, especially the eyes and anogenital region.
The two most common causes of DG are lichen planus (LP) and mucous membrane pemphigoid (MMP). Less likely are pemphigus, dermatitis herpetiformis (DH), linear immunoglobulin A disease (IAD), and epidermolysis bullosa. Other causes of DG that present with erythema and ulcerative lesions include plasma cell gingivitis (PCG), systemic LE, discoid LE, chronic ulcerative stomatitis (CUS), and granulomatous disorders (including orofacial granulomatosis, Crohn disease, and sarcoidosis). Local hypersensitivity responses to various substances such as mouthwashes, dental materials, drugs, cosmetics, chewing gum, cinnamon, sodium lauryl (a usual ingredient of toothpaste) may also play a role as causative agents in some patients (1).
In differentiating the two leading causes of DG, LP and MMP, a mucosal biopsy with direct immunofluorescence (DIF) is essential. Personally, I prefer not to biopsy gingivae, so I refer my patients to oral surgery with a specific request for H&E and DIF. (I have examined many patients with DG who have been biopsied by oral surgeons for routine microscopy, but no DIF was performed).
Haefliger et al reported on the successful management of isolated, refractory DG due to MMP by utilizing rituximab. The patients had been inadequately treated with standard therapies (i.e. topical corticosteroids, careful oral hygiene, doxycycline, nicotinamide, dapsone, prednisolone, and mycophenolate mofetil). Each was administered rituximab delivered by 2 infusions of 1000 mg each, with an interval of 2 weeks between the infusions. After follow-up at 2 years, 1 patient was in complete remission on no treatment, and 2 were in complete remission with minimal adjuvant maintenance therapy (dapsone 12.5 mg daily in one patient and sulfasalazine 1 g daily in the other) (2). This is encouraging, however, rituximab should be considered a second-line treatment reserved for recalcitrant cases pending further confirmatory studies.
Is rituximab valuable for recalcitrant oral LP?
Very little data addresses this question. There is a solitary report of a 59-year-old woman diagnosed with esophageal LP who was successfully treated with rituximab (3). Paradoxically, a case of a rituximab-induced oral lichenoid reaction has been reported in a 43-year-old woman treated for a follicular lymphoma. Interestingly, her extensive lesions involved the lips, tongue, and buccal mucosa; there was no mention of DG. She responded to discontinuation of rituximab combined with the use of steroids (systemic, topical and intralesional) (4).
Anyone who has gleaned the medical dermatology literature the past few years is aware that rituximab has been extraordinarily effective in treating autoimmune bullous disorders. I have had several patients who have derived ample benefit from the infusions. I try to suppress my concerns about the possibility of progressive multifocal leukoencephalopathy – while it has not become a major issue, the concerns are legitimate. As stated by Al-Tawfiq et al, “further studies are needed to quantify the risk and identify the patients for whom rituximab should be avoided.” (5).
- Al-Abeedi F, et al. The differential diagnosis of desquamative gingivitis: Review of the literature and clinical guide for dental undergraduates. J Int Oral Health 2015; 7 (Suppl 1): 88-92.
- Haefliger S, et al. Rituximab for the treatment of isolated refractory desquamative gingivitis due to mucous membrane pemphigoid. JAMA Dermatol 2016; 152: 1396-8.
- Goñi Esarte S, et al. Rituximab as rescue therapy in refractory esophageal lichen planus. Gastroenterol Hepatol 2013; 36: 264-7.
- Kuten-Shorrer M, et al. Lichenoid mucosal reaction to rituximab. Oncologist 2014; 19: e12-3.
- Al-Tawfiq JA, et al. Progressive multifocal leukoencephalopathy (PML) in a patient with lymphoma treated with rituximab: A case report and literature review. J Infect Public Health. 2015 Sep-Oct;8(5):493-7.
*The image is from Pocket Dentistry