Pemphigus vegetans: An unusual presentation.

Pemphigus vegetans is a rare variant of pemphigus vulgaris that is characterized by vegetating lesions primarily in the flexures. We report a 45-year-old male patient with an unusual presentation of the disease. A careful analysis of the clinical and laboratory findings enabled us to reach a diagnosis and successfully treat the patient.

INTRODUCTION

Pemphigus vulgaris is an autoimmune disorder characterized by production of IgG autoantibodies against intercellular adhesion protein desmoglein, leading to acantholysis. Pemphigus vegetans is a rare variant of pemphigus vulgaris characterized by heaped up, cauliflower-like vegetating plaques in the flexures.[1] The disorder affects chiefly middle-aged adults. Lesions are primarily flexural, although vegetations may occur at any site.[2] We report a case of pemphigus vegetans involving the oral mucosa and perioral region which was initially mistaken for malignancy due to its unusual presentation.

CASE REPORT

A 45-year-old wood furniture painter was brought to the dermatology outpatient department with complaints of recurrent painful oral erosions for the last three years. Six months prior, he developed extremely itchy, irregular reddish and ulcerative patches around the mouth that gradually extended into his nose. He also developed scattered patches over the scalp and glans penis with oozing and pus formation. On examination, he had a well-defined, irregular, hypertrophic, fissured plaque with oozing and crusting surrounding the mouth, extending above up to and into the ala nasii [Figure 1] and within to involve both the lips, the entire oral mucosa, and oropharynx. The tongue showed white folds and fissures, and there was white cobblestoning of the entire palate. The scalp showed three well-defined, approximately 2.5 × 3 cm, exudative, yellowish plaques with pustules and intact hair follicles within them. There was single 3–4 mm erosion over glans penis. There were four to five firm, discrete, nontender, 1–1.5 cm, submandibular and anterior cervical lymph nodes on both sides of the neck. There were no other systemic findings. As the patient was a heavy smoker and a chronic alcoholic, a possibility of the lesion being a malignant neoplasm was considered. His routine investigations including hemoglobin, total leukocyte count, differential leukocyte count, liver function tests, renal function tests, and X-ray chest were essentially normal, except for a raised eosinophil count (11%). A KOH preparation for fungus was negative. Gram's smear from the lesion revealed several polymorphonuclear cells (neutrophils, eosinophils) along with gram-positive cocci and gram-negative bacilli. Repeated culture for bacteria only showed contaminants. The first biopsy taken from the perioral region showed acanthosis, papillomatosis, few dysplastic keratinocytes, neutrohils, and eosinophils in the epidermis. There was perivascular mixed inflammatory cell infiltrate of eosinophils, plasma cells, lymphocytes, and histiocytes. The patient was given several courses of broad-spectrum antibiotics along with supportive treatment without any improvement. He was then given a 2-week course of Itraconazole 100 mg twice daily on empirical basis. He subsequently also received a 2-week course of standard antitubercular drugs with disappointing results. A positron emission tomography-computed tomography (PET-CT) scan was also carried out on suspicion of malignancy which revealed fluorodeoxyglucose (FDG)-avid lesions in the scalp, perioral region including lips, and nose, and bilateral cervical lymphadenopathy. Excision biopsy of one of the enlarged lymph nodes revealed reactive lymphadenitis. A repeat biopsy was performed as the lesion continued to persist and expand. In addition to the findings seen in the first biopsy sample, microabscesses containing eosinophils and an intraepidermal cleft with acantholytic cells was noted in one of the cut sections [Figures 2 and 3]. This led us to include pemphigus vegetans in the differential diagnosis. A serum sample was sent for indirect immunofluorescence, which confirmed the diagnosis. The patient was then put on intravenous dexamethasone 8 mg twice daily for 1 week and had a dramatic response with significant clearing of his lesions. In the 2nd week, the dose was reduced to 4 mg twice daily. By this time, he had almost 80% clearing of his perioral [Figure 4] and scalp lesions and complete healing of the oral and genital mucosa. He has been enrolled for standard dexamethasone cyclophosphamide pulse regimen[3] and is under regular follow-up.

Figure 1

Clinical photograph showing well-defined, irregular, hypertrophic, fissured plaque with oozing and crusting surrounding the mouth, extending above into the ala nasii

Figure 2

Histopathologic photograph showing the presence of microabscesses containing eosinophils and an intraepidermal cleft

Figure 3

High-power view of Figure 3

Figure 4

Clinical photograph showing dramatic response with significant clearing of the patient's lesions after treatment

DISCUSSION

Pemphigus vegetans is a rare variant of pemphigus vulgaris, first described by Neumann in 1876.[3] Two subtypes – Neumann and Hallopeau types are recognized, which are differentiated based on their clinical presentation, course, and response to treatment.[45] Unlike pemphigus vulgaris which has a classical clinical picture and is easy to diagnose most of the time, pemphigus vegetans, especially the Hallopeau variant, has no clinical resemblance to a vesiculobullous disorder. It presents as heaped up vegetating and verrucous plaques mainly in the flexures. Oral lesions are common.[6] Other areas are very uncommonly involved, though reports of lesions limited to foot, oral mucosa, lips, or toes have been described.[47-9] Hence, a lack of familiarity or clinical suspicion may lead to the diagnosis being missed. The possibility of a dermatopathologist concentrating more on the given clinical differential diagnosis, especially when the relevant findings are subtle on biopsy and are present only in few cut sections, is ever present. Also, the use of newer sophisticated diagnostic tools such as PET-CT that showed increased uptake of 18 FDG by these lesions and presence of multiple lymph nodes, a finding usually seen in neoplastic disorders, could have led to a wrong diagnosis if seen in isolation. In such cases, relying on repeated clinical reviews, repeat biopsies, relevant feedback to the pathologist, and use of other diagnostic modalities (immunofluorescence study in our case) is the only way we can arrive at a correct diagnosis [Figure 5]. This becomes all the more relevant when the disease occurs at unusual sites such as perioral region as in our case.

Figure 5

Immunoperoxidase staining of lower part of epidermis (intercellular area)