[Significance of anticardiolipin antibodies in connective tissue diseases]

Recent attention has focused on the possibility that the presence of Anticardiolipin Antibodies (ACA) in patients with connective tissue diseases, particularly with Systemic Lupus Erythematosus (SLE), may be associated with clinical and serological symptoms that identify a particular subset of patients. This group is characterized by recurrent arterial and/or venous thrombosis, multiple abortions and or intrauterine fetal death, presence of Lupus AntiCoagulant (LAC), false positive VDRL, thrombocytopenia and neuro-psychiatric diseases. These clinical features may identify the so-called "Anticardiolipin Syndrome". In this work, we have measured ACA, by ELISA test, in 194 serum samples: 97 SLE patients, 5 Mixed Connective Tissue Disease (MCTD), 8 Progressive Systemic Sclerosis (PSS), 7 Dermato/PolyMyositis (D PM), 3 Sjögren Syndrome (SS), 3 Unclassifiable Connective Tissue Disease (UCTD), 9 Rheumatoid Arthritis (RA), 1 Idiopathic Anticardiolipin Syndrome, 19 cases of Miscellanea, 42 healthy controls. The Optical Density (O.D.) was greater than 0 (higher than 0) in 89 serum samples (out of the 194): 43 SLE, 4 MCTD, 4 PSS, 3 D PM, 1 SS, 7 RA, 10 cases of Miscellanea, the Idiopathic Anticardiolipin Syndrome and 16 healthy controls. The O.D. was greater than m (greater than mean healthy controls level) + 3 Standard Deviations (S.D.) in a restricted number of cases (25 out of the 194): 14 SLE, 2 MCTD, 1 PSS, 1 D/PM, 1 SS, 1 RA, 3 cases of Miscellanea and 2 healthy controls. Therefore, we have noticed, first of all, the lack of specificity of positive results obtained: all the groups of patients, healthy controls included, had low as well as high levels of ACA. Moreover, we have examined the relationship between the presence of ACA and typical clinical features of the so-called. "Anticardiolipin Syndrome"; there was not difference of clinical symptoms between patients with low or high ACA levels. We have also clinically examined ACA negative patients; most of them had one or several clinical features of the "Syndrome", until almost complete clinical picture. Therefore, no correlation was found between clinical picture and immunological features of the so-called "Anti-cardiolipin Syndrome"; we would not exclude the existence of the "clinical" subset of patients, but of the "immunological" subset.