Introduction
The clinical associations of NuMA and HsEg5 antibodies, the main anti-mitotic spindle apparatus autoantibodies, remain unclear
due to their extremely low prevalence.
Patients and Methods
We have analysed the clinical data of 40 anti-NuMA- (0.87‰) and 7 anti-HsEg5- (0.15‰) positive patients detected during routine
immunofluorescence examination of 45,804 sera. NuMA reactivity was further confirmed by immunoblotting.
Results
Antibodies to HsEg5 did not associate with any specific pathology. NuMA positivity associated with a diagnosis of connective
tissue disease (CTD) in 18 patients (45%), primary Sjögren or sicca syndrome and undifferentiated connective tissue disease
being the most represented. Seven patients (17.5%) were diagnosed with different organ-specific autoimmune diseases, whereas
in the other 15 patients (37.5%), no autoimmune pathology could be documented.
Conclusions
Therefore, although both anti-mitotic spindle apparatus antibodies are not associated to a defined autoimmune pathology, the
presence of NuMA antibodies, mainly at high titers, may be an indication for a more extensive screening of CTD.
Keywords Mitotic spindle apparatus autoantibodies - NuMA protein - HsEg5 protein - connective tissue diseases