[Sarcoidosis].

Abstract

Clinical/methodical issue: Sarcoidosis is a systemic inflammatory disease of unknown cause, characterized by the formation of noncaseating epithelioid cell granulomas, which can potentially affect nearly every organ. The lungs and mediastinal lymph nodes are most commonly affected-with granulomatous involvement found in approximately 90% of cases. Typically, younger adults are affected by sarcoidosis. The clinical picture and the course of the disease can vary significantly, which is why it is also referred to as the "great mimicker". The aim of this review is to provide an overview on the imaging findings in patients with sarcoidosis. In addition, the current diagnostic and therapeutic management will be elaborated.

Standard radiological methods: The conventional chest radiograph has long been considered a fundamental examination in suspected sarcoidosis. Traditionally, staging is performed according to the Scadding classification (stages 0-IV). However, computed tomography (CT) is increasingly used due to its higher accuracy and availability.

Methodical innovations: Recently, seven dedicated radiologic phenotypes of sarcoidosis have been identified on CT, comprising four nonfibrotic and three fibrotic subtypes. Given the superior accuracy of CT and its potential role in therapy monitoring, baseline high-resolution CT (HRCT) is increasingly recommended.

Practical recommendations: Sarcoidosis is an inflammatory multisystem disease involving the lungs and thoracic lymph nodes in approximately 90% of cases. Current guidelines still recommend chest radiography as the initial imaging modality for diagnosis and staging; however, CT is increasingly being used.