Overlap syndrome - Altmeyers Encyclopedia

Synonym(s)

PM-SCL Syndrome

Antibody-associated, clinically overlapping autoimmune diseases that meet the classification criteria of two or more clinically-phenomenologically defined autoimmune diseases or exhibit major symptoms of these diseases. The majority of these diseases are associated with characteristic autoantibodies against non-organ-specific nuclear or cytoplasmic autoantibodies whose formation is related to certain immunogenetic characteristics. Overlap syndromes are considered to exist when at least 2 of the following conditions are fulfilled: systemic lupus erythematosus (SLE); systemic scleroderma; idiopathic myositis (IM); Sjögren's syndrome (SS); rheumatoid arthritis (RA).
Serologically overlap syndromes characterized by distinct ANA patterns:

MCTD = mixed connective tissue disease, detection of U1-RNP antibodies.
PM-Scl syndrome = overlap syndrome with signs of PSS, dermatomyositis and chronic polyarthritis (rheumatoid arthritis); detection of PM-Scl antibodies.
Antisynthetase syndrome or Jo1 syndrome = overlap syndrome with myositis, fibrosing alveolitis, polyarthritis; less frequent association with sicca symptoms, Raynaud's phenomenon, PSS. In more than 80% of the cases detection of antibodies against aminoacyl-tRNA synthetases or Jo-1 antibodies.
Overlap syndrome with Ku antibodies = clinical picture with symptoms of systemic scleroderma, myositis and SLE.

Csepregi A et al (2003) Characterization of a lipoyl domain-independent B-cell autoepitope on the human branched-chain acyltransferase in primary biliary cirrhosis and overlap syndrome with autoimmune hepatitis. Clin Dev Immunol 10: 173-181
Genth E (2000) Clinical manifestations, immunology and genetics of overlap syndromes. In: Plettenberg A, Meigel WN, Moll I (Hrsg) Dermatology at the threshold of the new millennium. Springer, Berlin Heidelberg New York, S. 57-59
Lee MW et al (2003) Lupus erythematosus cells in the cutaneous lesion of overlap syndrome of dermatomyositis-SLE-like disease. At J Dermatopathol 25: 272-274
Raijmakers R et al (2004) PM-Scl-75 is the main autoantigen in patients with the polymyositis/scleroderma overlap syndrome. Arthritis Rheum 50: 565-569
Watanabe K et al (2003) Polyangitis overlap syndrome: a fatal case combined with adult Henoch-Schonlein purpura and polyarteritis nodosa. Catholic Int 53: 569-573