Background: Anti-multiple nuclear dots (MND) antibodies are the markers of primary biliary cirrhosis (PBC), but can also be found in patients with other autoimmune diseases.
Methods: We looked for MND in 9189 sera belonging to 6240 patients stored for autoimmune diseases with prevalent cutaneous features.
Results: Fifty sera proved anti-MND-positive and came from 15 different patients: 6 had lupus erythematosus, 2 dermatomyositis, 2 lichen planus, 1 stroke, 1 telogen effluvium, 1 autoimmune thrombocytopenia, and 2 undifferentiated connective tissue disease.
Conclusions: Anti-MND antibodies can be found not only in patients with PBC, but in connective tissue diseases as well. They can be associated with other fluoroscopic patterns and their titers can vary over the years, never correlating with the disease activity or with particular cutaneous features. Although anti-MND antibodies found are directed to the Sp100 antigen of the nuclear dots, it remains unclear whether their molecular target is the same amino-acid domain as in PBC.