Prospective study of a systemic sclerosis/dermatomyositis overlap patient presenting with anti-Ku and anti-Ki antibodies

Abstract A 60-year-old woman visited the Keigu Clinic in January 1998 complaining of morning stiffness and flexion contracture of the distal interphalangeal joint. Blood tests showed the presence of antinuclear antibody at a 1 : 40 dilution with speckled staining. She was suspected of having Heberden's node. Nine months later, she developed Raynaud's phenomenon, sclerodactyly, and Gottron's sign, and was diagnosed with systemic sclerosis/dermatomyositis (SSc/DM) overlap. Blood tests revealed the presence of antinuclear antibody at a 1 : 5120 dilution, along with high titer of anti-Ku and anti-Ki antibodies. Subsequently, the patient developed interstitial pneumonia in January 2000. It is thought that the appearance of antinuclear antibody and development of other immunological events played an important role in determining this patient's limited SSc/DM overlap.