Sarcoidosis Flashcards
sarcoidosis
multi-system disorder of unknown cause
commonly affects young to middle-aged adults
usually characterized by interstitial lung disease and hilar/mediastinal lymphadenopathy
commonly affects eyes, skin, and othe rorgans
noncaseating granulomatous inflammation on biopsy without evidence that granuloma formation was triggered by infection or foreign bodies
decreased cutaneous delayed-type hypersensitivity and increased Th1 inflammatory response at sites of disease activity
epidemiology of sarcoidosis
African Americans more at risk
age of diagnosis 20-40
slight female predominance
polygenic, complex, non-medelian inheritance
pathogenesis of sarcoidosis
initiation of granuloma formation
deposition of poorly soluble antigenic material
oligoclonal expansion of T cells at sites of disease
Th-1 polarized cytokine response
release of TNF by T cells and macrophages
presence of circulating immune complexes
recent evidence suggests presence of mycobacterial antigens
pathology of sarcoidosis
discreet, compact, non-caseating granuloma
highly differentiated macrophages - epithelioid histiocytes and multinucleated giant cells
lymphocytes also present
organ distribution of sarcoid granulomas
lung, lymph nodes, liver, spleen, skin
lung distribution of non-caseating granulomas
peribronchovascular, perilobular, subpleural
end-stage pulmonary sarcoidosis - parenchymal fibrosis and honeycombing
clinical manifestations of sarcoidosis
pulmonary involvement in 90-95%
asymptomatic hilar lymphadenopathy
cough, dyspnea, chest pain
chest physical exam usually normal - clubbing is rare
constitutional symptoms of sarcoidosis
fever, fatigue, malaise, wieght loss in 30% of patients
mostly in African Americans
skin manifestations of sarcoidosis
erythema nodosum - good prognosis, raise, tender on anterior shin, no granulomas underneath
hyperpigmented plaques - granulomatous lesion underneath
lupus pernio - difficult to treat, associated with poor prognosis
Stage I sarcoidosis CXR
bilateral hilar lymphadenopathy without interstitial pulmonary infiltrates
Stage II sarcoidosis CXR
bilateral hilar lymphadenopatyh with intersitial infiltrates
Stage III sarcoidosis CXR
parynchymal infiltrate without bilateral hilar lymphadenopathy
Stage IV CXR and CT
end-stage fibrosis
HRCT patterns suggestive of sarcoidosis
nodular opacities typically peribronchovascular in location
often with a “tree-in-bud” appearance, distributed in the upper and middle lung zones
subpleural nodules also seen
pulmonary function tests for sarcoidosis
restrictive defect is characteristic
airflow obstruction seen in up to 20%
decreased DLCO is common
correlation of PFTs with pathology and CXR or CT is poor
do not predict response to therapy well
diagnostic methods for sarcoidosis
biopsy via flexible bronchoscopy
biopsy of other sites
mediastinoscopy/biopsy
What is a favorable predictor of prognosis for sarcoidosis?
Lofgren’s syndrome
treatment of sarcoidosis
corticosteroids for stages II and III
treat pulmonary disease when symptoms are severe or progressive
treat neurosarcoidosis, cardiac disease, eye disease
relapse common after tapering of treatment
alternative therapies for sarcoidosis
methotrexate - immunosuppresive agent used if steroids are ineffective
infliximab, adalimumab, rituximab - anti-TNF biologic agents, off-label use
