From the Guidelines
Sarcoidosis is diagnosed based on a combination of clinical presentation, histological findings, and exclusion of alternative causes.
Diagnostic Criteria
The diagnosis of sarcoidosis is based on three major criteria:
- Compatible clinical presentation: a spectrum of manifestations ranging from asymptomatic to progressive and relapsing disease, with certain clinical features considered highly specific for the disease, such as L¨ofgren’s syndrome, lupus pernio, and Heerfordt’s syndrome 1.
- Nonnecrotizing granulomatous inflammation: finding nonnecrotizing granulomatous inflammation in one or more tissue samples, with characteristic features including compact, tightly formed collections of large “epithelioid” histiocytes and multinucleated giant cells, and perilymphatic location around bronchovascular bundles and fibrous septa containing pulmonary veins 1.
- Exclusion of alternative causes: excluding alternative causes of granulomatous disease, such as tuberculosis, lymphoma, and other conditions that may present with similar clinical and histological features 1.
Key Pathological Features
The key pathological features of sarcoidosis include:
- Granuloma presence and morphology
- Lesion location, such as perilymphatic and around bronchovascular bundles
- Accompanying histology, such as sparse surrounding lymphocytic infiltrate
- Negative microorganism stains and cultures
- Multidisciplinary clinical features, such as intra- and extrathoracic involvement 1.
From the Research
Diagnostic Criteria for Sarcoidosis
The diagnostic criteria for sarcoidosis are based on a combination of clinical, radiologic, and histologic findings. The following are the key criteria:
- A compatible clinical and radiologic presentation 2, 3, 4, 5, 6
- Pathologic evidence of noncaseating granulomas 2, 3, 4, 5, 6
- Exclusion of other diseases with similar findings, such as infections or malignancy 2, 3, 4, 5, 6
Clinical Presentation
Sarcoidosis can present with a variety of symptoms, including:
- Unexplained cough or shortness of breath 2
- Constitutional symptoms, such as fever or weight loss 2
- Skin lesions, uveitis, or other extrapulmonary manifestations 3
- Cardiac or neurological symptoms, although these are less common 3
Histologic Findings
The histologic findings of sarcoidosis are characterized by:
- Noncaseating granulomas, which are a hallmark of the disease 2, 3, 4, 5, 6
- Granulomatous inflammation, which can be found in various organs, including the lungs, lymph nodes, and skin 3, 4
Diagnostic Approach
The diagnostic approach to sarcoidosis involves:
- Weighing the clinical evidence for and against the diagnosis 4
- Histologic examination of an affected tissue in most instances 4
- Exclusion of alternative diseases with similar findings 2, 3, 4, 5, 6
- Consideration of specific clinical features, such as Löfgren's syndrome or lupus pernio, which are highly specific for sarcoidosis 3