Lupus pneumonitis is rare, although minor pulmonary function abnormalities are common. Life-threatening pulmonary hemorrhage may rarely occur. Pericarditis is often present. More serious rare complications are coronary artery vasculitis or fibrosing myocarditis. Libman-Sacks lesions are described under Noninfective Endocarditis in Ch.
Generalized adenopathy is common, particularly in children, young adults, and blacks.
CNS involvement can cause headaches, personality changes, stroke, epilepsy, psychoses, and organic brain syndrome. Renal involvement may be benign and asymptomatic or relentlessly progressive and fatal. The most common manifestation is proteinuria. The histopathology of the renal lesion varies from a focal, usually benign glomerulitis to a diffuse membranoproliferative glomerulonephritis. Because milder cases of lupus have been increasingly detected, the percentage of patients with clinically significant renal disease has declined.