Lichen planus pemphigoides

To the Editor,

Lichen planus pemphigoides (LPP) presents with lesions of lichen planus (LP) which are of acute onset and generalised followed by appearance of large, tense bullae on them or on uninvolved skin.[1],[2] Histologically, subepidermal bullae with an eosinophilic infiltrate that is not bandlike, is seen when biopsy is taken from bulla not associated with lesions of LP.[3]

A 50-year-old lady presented with acute onset of lesions of LP scattered over wrists, forearms, feet, ankles, legs, abdomen and upper chest. A few days later, during which she was on antihistamines and topical steroids, there was sudden appearance of tense vesicles and bullae all over the body including areas uninvolved by LP. Patient complained of itching. There was no underlying erythema. There were no mucosal lesions. Histology of specimen taken from skin with only bulla revealed subepidermal blisters without changes of LP, but, histopathology of skin showing lesions of LP were consistent with that of LP. Routine haemogram, urinalysis, chest X-ray etc were within normal limits. With a 2 to 3 week tapering dose of systemic corticosteroids the bullae subsided and the lesions of LP flattened and almost subsided. Till date there has not been any relapse.

Recent studies suggest that although LPP antigen and bullous pemphigoid (BP) antigen have similar ultrastructural localization but they have different properties and LPP is a distinct entity.[2] The possibility of bullous LP was excluded because bullae were more numerous on univolved skin and changes of LP were not seen with subepidermal bulla on histology. Immunoelectron microscope would have shown deposition of IgG and C3 in the base of the bulla in LPP as distinct from similar deposits at the roof of the bulla in BP,[1] but was not possible in our institution. Thus, the age of the patient, the clinical findings and histology and the rapid response to treatment suggested the diagnosis of LPP.