Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (23 page)

   Anti-PM/Scl autoantibodies indicate associated myositis.

   Antibodies to RNA polymerase II may be found in SSc and SLE patients.

   RF is positive in 30% of patients. When present in high titer, it suggests overlap disease.

   Serum and urine protein electrophoresis may be indicated to exclude monoclonal gammopathies in patients with symmetrical skin induration but no Raynaud phenomenon.

   Eosinophilia is common.

   ESR may be normal, mildly increased, or greatly increased.

   Skin biopsy is rarely necessary.

Suggested Reading

Gabrielli A, Avvedimento EV, Krieg T. Scleroderma.
N Engl J Med.
2009;360(19):1989–2003.

   
AUTOIMMUNE VASCULITIS

See Vasculitis (Chapter
3
, Cardiovascular Disorders).

EOSINOPHILIC GRANULOMATOSIS WITH POLYANGIITIS (CHURG-STRAUSS SYNDROME)

   Definition

Eosinophilic granulomatosis with polyangiitis (EGPA), also referred to as Churg-Strauss syndrome (CSS) or allergic granulomatosis and angiitis, is a multisystem vasculitis affecting small and medium-sized blood vessels and characterized by asthma, allergic rhinitis and sinusitis, eosinophil-rich inflammation, and peripheral blood eosinophilia.

EGPA has three phases:

   Prodromal (allergic) phase: characterized by airway inflammation (asthma and allergic rhinitis).

   Eosinophilic phase: peripheral eosinophilia and eosinophilic infiltration of multiple organs, especially the lungs and gastrointestinal tract.