The clinical significance of antinucleolar antibodies

The importance of antinucleolar antibodies seen by indirect immunofluorescence on HEp-2 cells, although associated with systemic sclerosis (SSc), in unselected patients is unknown.

To determine the true clinical significance of antinucleolar antibodies in an unselected patient population.

Antinucleolar antibody (ANoA) positive samples were identified in the immunology laboratory during routine autoimmune screening tests; case notes were reviewed using a standard proforma.

104 patients with ANoA were identified and ANoA+ samples were subclassified into homogeneous, clumpy and speckled antinucleolar types. SSc was evident in only two (1.8%) patients. Other connective tissue diseases were identified in 33 patients (32%); 22 patients (21%) had evidence of various malignancies. Both disordered liver function and anaemia were seen in 22 patients and were the commonest laboratory abnormalities.

Neither the presence nor subtype of ANoA is specific for systemic sclerosis. Laboratory comments appended to results should reflect this fact.