Sarcoidosis

Definition: Multisystem disorder characterised by non-caseating epithelioid cell granulomata.

Demographics

Prevalence 27:100 000. M:F roughly equal, slighty more common in women. More common among West Indians.

Aetiology

Idiopathic. ?infection.

Pathophysiology

MHC class II macrophages present unknown antigen to TH1. T-cells proliferate and release immune mediators. Macrophages are recruited and transform into epitheliod cells and Langhan's giant cells. langhan's cells may show cytoplasmic inclusions: calcium carbonate crystals, Schaumann bodies, asteroid bodies.

Presentation

Breathlessness, anterior uveitis, abnormal CXR, superficial lymphadenopathy. Constitutional: fever, malaise, weightloss.

Clinical features

Multisystem:

Diagnosis

If barn door, then no histology required.

Monitoring

Serial CXR, serum ACE levels.

Treatment

Controversial.
Remits without treatment in 2/3 of whites, 1/3 of blacks. Fatal in <3%.
Steroids may help the more severe manifestations. May try chloroquine. Azathioprine or methotrexate may be tried as steroid sparing agents.