Granuloma annulare as a leading mimicking granulomatous disease: Clinical and histopathological study in a series of 47 cases

Abstract

Objective To do a full clinical and histopathological evaluation and to present the diverse clinical presentations of different patients to make everybody aware of how it is difficult to establish the right diagnosis in many instances.   Methods This is a cross-sectional descriptive study that was carried out during the period from 2014-2023 where all patients with granuloma annulare were described. All demographic features were reported. A full clinical history and examination were carried out. Biopsy for histopathological assessment was also done.   Results The data of forty-seven patients were analyzed and assessed. All patients were asymptomatic. The commonest sites affected were hands, forearms and trunk in symmetrical ways. To a lesser degree, three patients (6.38%) had penile involvement. Scalp was involved in one (2.12%) patient. The main histopathological picture was palisading granuloma but some patients had little inflammatory reaction while in one patient there was dermal necrobiotic degeneration with no inflammatory reaction.   Conclusion Granuloma annulare presented mainly with typical annular beaded lesions, which were generalized in 87.23%, localized in 8.51% and profundus in 4.25% that might have different clinical distribution. Although some patients had only one site affected like the penis and scalp. The histopathological picture was palisading granuloma. It might imitate many granulomatous diseases both in its clinical and histopathological pictures with many overlapping features but sarcoidosis remains the most important mimicking disease. Still, there is a vague activating triggering factors for GA.