Multiple brown facial lesions: A diagnostic challenge

Question

What is your diagnosis?

Answer

Granuloma faciale

Discussion

Skin biopsy from the lesion revealed a pandermal, dense infiltrate below a well-formed grenz zone [Figure 2a]. The infiltrate was composed of neutrophils, karyorrhectic debris, occasional eosinophils, plasma cells, lymphocytes, and histiocytes with an intervening sclerotic dermis [Figure 2b]. No leukocytoclastic vasculitis changes, including fibrin deposition or erythrocyte extravasation were noted. Based on clinico-pathological correlation, a diagnosis of multiple granuloma faciale was made.

Granuloma faciale is an uncommon dermatosis with few large studies available.^1,2 It has been traditionally classified as an eosinophilic chronic fibrosing leukocytoclastic vasculitis, although it has been shown that eosinophils rarely comprise the main cell type and leukocytoclasia can be absent or minimal in up to 33% cases.² The disease has a slight predominance in males (1.6:1), with the majority of lesions being solitary, although multiple lesions can be seen in up to 38% cases.^1-3 While granuloma faciale is believed to occur predominantly on the face, exclusive extra-facial involvement has also been reported in up to 13% cases.^1,4-6

Granuloma faciale is a disease of uncertain aetiology, usually occurring in middle age.² It presents as well-circumscribed, asymptomatic, erythematous to skin- coloured, soft, smooth papules, plaques or nodules with prominent follicular ostia. Surface changes are rare.^1,2 Differential diagnoses include tumid lupus erythematosus, angio-lymphoid hyperplasia with eosinophilia (ALHE), sarcoidosis, pseudolymphoma, lymphoma, non-Langerhans cell histiocytosis (NLCH), juvenile xanthogranuloma, mastocytoma, erythema elevatum diutinum (EED).^1,2

Histopathology aids the diagnosis and usually reveals a normal to atrophic epidermis and follicular plugging in up to 60% cases, with a narrow grenz zone below (in up to 74% cases).^1,2 The distribution of inflammatory infiltrate is perivascular in about 60% cases, though diffuse infiltrate is also common. Although eosinophils have been traditionally considered important in making a diagnosis, a large series showed that they were present in only 57% of cases and never constituted the major cellular infiltrate.² Neutrophils and lymphocytes have been shown to be present in the majority of cases, and they are in fact the predominant infiltrate in about half of the cases. Occasionally, lymphoid follicles can be seen, but germinal centre formation is rare. Vascular changes are seen in up to 62% cases, consisting of perivascular infiltrate, leukocytoclasia, erythrocyte extravasation, and hemosiderin deposition. However, necrotising vasculitis is rare, and was seen in only 7% cases in a large series.² While many previous studies have shown high direct immunofluorescence (DIF) positivity, this has been challenged in larger cohorts, in which none of the lesions showed positivity.^2,4 The major histological differential diagnoses include EED and ALHE.²

Treatment of this entity has been challenging; in part because of difficulty in diagnosing the disorder, and therefore, there is a lack of high-quality studies availability to guide evidence. Medical strategies promulgated include topical or intralesional corticosteroid, tacrolimus ointment, anti-neutrophilic agents like antimalarials, dapsone, and colchicine. Physical modalities include dermabrasion, fractional ablative lasers, surgical excision, radio-frequency ablation, and cryotherapy.^1,2 In view of multiple lesions, oral dapsone has been planned for our case.

In conclusion, granuloma faciale is an under-diagnosed condition requiring clinico-pathological correlation to establish a diagnosis. While traditionally thought to occur as a solitary lesion, the multiplicity of lesions should not hinder its diagnosis.