Pulmonary sarcoidosis (staging)
Thoracic sarcoidosis can be staged on a chest radiograph with implications for prognosis although HRCT and FDG-PET provide more information to help guide treatment.
Chest radiographs have been the mainstay of staging thoracic sarcoidosis for many decades with fair interobserver concordance . However, this system correlates poorly with symptom severity, extrapulmonary disease, pulmonary function tests and need for treatment . HRCT and FDG-PET can provide more information than chest x-ray to help guide treatment decisions .
On PA chest radiographs, sarcoidosis can be classified into five stages :
- stage 0: normal chest radiograph
- frequency at presentation: 5-15%
- stage I: hilar or mediastinal nodal enlargement only
- frequency at presentation: 25-65%
- spontaneous resolution: 60-90%
- stage II: nodal enlargement and parenchymal disease
- frequency at presentation: 20-40%
- spontaneous resolution: 40-70%
- stage III: parenchymal disease only
- frequency at presentation: 10-15%
- spontaneous resolution: 10-20%
- stage IV: end-stage lung disease (pulmonary fibrosis)
- frequency at presentation: 5%
- spontaneous resolution: 0%
Although in general patients progress from one stage to the next, this system does not correlate particularly well with clinical severity . In fact, chest x-ray appearances are often more dramatic than functional impairment .
History and etymology
In 1961, Scadding published a classification system adapted from one initially proposed by Karl Warm . Sometimes sarcoidosis is described as being staged with Siltzbach system , although this paper was not published until 1967 , and in turn, makes reference to classification systems already in place.
- Silzbach sarcoidosis chest radiographic staging system
- Sarkoidose Wurm Klassifikation
- Sarkoidose Scadding Stadium