Sarcoid-like reactions: a comprehensive review of granulomatous diseases mimicking sarcoidosis.

INTRODUCTION

Sarcoid-like reactions (SLR) are granulomatous conditions characterized by non-caseating epithelioid cell granulomas that mimic sarcoidosis but arise in patients who do not fulfill diagnostic criteria for systemic sarcoidosis. The overlap with sarcoidosis poses a significant challenge, as misdiagnosis can lead to inappropriate treatment.

AREAS COVERED: We performed a comprehensive review of the available literature summarizing SLRs associated with malignancies, infections, and most relevant drugs involved, discussing the timing of onset, patterns of organ involvement, and prognostic implications. Management strategies are discussed according to the underlying trigger, ranging from simple observation to corticosteroids or targeted immunosuppression, and from pathogen-directed therapy to careful continuation or modification of anticancer treatment.

EXPERT OPINION: SLRs represent a diagnostic and pathogenetic challenge due to the plasticity of the granulomatous immune response, which can be triggered by drugs, malignancy, or other stimuli, often mimicking systemic sarcoidosis. Dedicated studies are needed to develop standardized diagnostic criteria and algorithms that integrate clinical, histological, and immunological features to accurately distinguish SLRs from sarcoidosis and guide management.