Comment
Ulcerative (or erosive) lichen planus is a rare form of lichen planus. Ulcerative lichen planus most commonly presents as erosive lesions of the oral and genital mucosae but rarely can involve other sites. The palms and soles are the most common sites of cutaneous involvement, with lesions frequently characterized by severe pain and limited mobility.2
We conducted a review of the Ovid MEDLINE database using the search terms ulcerative lichen planus and erosive lichen planus for articles from the last 30 years, focusing specifically on articles that reported cases of cutaneous involvement of ULP and successful therapeutic modalities. The Table provides a detailed summary of the cases from 1985 to present, representing a spectrum of clinical manifestations and successful treatments of ULP.1-13
Hepatitis C is a comorbidity commonly associated with classic lichen planus, while hepatitis B immunization has a well-described association with classic and oral ULP.12,14 Although hepatitis C was negative in our patient, we did find a chronic inactive carrier state for hepatitis B infection. Al-Khenaizan and Al-Mubarak12 reported the only other known case of ULP of the sole associated with positive serology for hepatitis B surface antigen.
Ulcerative lichen planus of the soles can be difficult to diagnose, especially when it is an isolated finding. It should be differentiated from localized bullous pemphigoid, epidermolysis bullosa acquisita, ulcerative lupus erythematosus, and dermatitis artefacta.13 The characteristic associated clinical features of plantar ULP in our patient and lack of diagnostic immunofluorescence helped us to rule out these alternative diagnoses.4 Long-standing ulcerations of ULP also pose an increased risk for neoplastic transformation. Eisen15 noted a 0.4% to 5% frequency of malignant transformation into squamous cell carcinoma in those with oral ULP. Therefore, it is important to monitor previously ulcerated lesions long-term for such development.
Plantar ULP is difficult to treat and often is unresponsive to systemic and local treatment. Historically, surgical grafting of the affected areas was the treatment of choice, as reported by Patrone et al.6 Goucha et al13 reported complete healing of ulcerations within 3 weeks of starting oral prednisone 1 mg/kg once daily followed by a maintenance dosage of 5 mg once daily. Tacrolimus is a macrolide immunosuppressant that inhibits T-cell activation by forming a complex with FK506 binding protein in the cytoplasm of T cells that binds and inhibits calcineurin dephosphorylation of nuclear factor of activated T cells.12 Al-Khenaizan and Al-Mubarak12 reported resolution of plantar ULP ulcerations after 4 weeks of treatment with topical tacrolimus. Eisman and Orteu7 also achieved complete healing of ulcerations of plantar ULP using tacrolimus ointment 0.1%.
In our patient, doxycycline also was started at the time of initiating the topical tacrolimus. We chose this treatment to take advantage of its systemic anti-inflammatory, antiangiogenic, and antibacterial properties. Our case represents rapid and successful treatment of plantar ULP utilizing this specific combination of oral doxycycline and topical tacrolimus.
Conclusion
Ulcerative lichen planus is an uncommon variant of lichen planus, with cutaneous involvement only rarely reported in the literature. Physicians should be aware of this entity and should consider it in the differential diagnosis in patients presenting with chronic ulcers on the soles, especially when lesions have been unresponsive to appropriate wound care and antibiotic treatment or when cultures have been persistently negative for microbial growth. The possibility of drug-induced lichen planus also should not be overlooked, and one should consider discontinuation of all nonessential medications that could be potential culprits. In our patient ibuprofen was discontinued, but we can only speculate that it was contributory to his healing and only time will tell if resumption of this nonsteroidal anti-inflammatory drug causes a relapse in symptoms.
In our patient, a combination of systemic and topical steroids, topical tacrolimus, and oral doxycycline successfully treated his plantar ULP. Our findings provide further support for the use of topical tacrolimus as a steroid-sparing anti-inflammatory agent for the treatment of plantar ULP. We also introduce the combination of topical tacrolimus and oral doxycycline as a novel therapeutic combination and relatively safer alternative to conventional immunosuppressive agents for long-term systemic anti-inflammatory effects.