Case of diffuse cutaneous systemic sclerosis with anti‐Ku and anti‐centromere antibodies

We report the case of a 58‐year‐old man who had an ulcer on the right middle finger that was cured by surgery 4 years before consultation with our department. A few years after the surgery, he noticed recurrence of the ulcer and sclerosis of the skin. At the initial examination, skin sclerosis was observed from the fingers to the upper arms and from the feet to the thighs. Pitting scars on the fingertips and punctured hemorrhages of the nail‐fold capillaries were also present. Gastroscopy showed slight reflex esophagitis. Laboratory findings were positive for antinuclear antibody (ANA; 1:640) with a speckled and discrete speckled pattern. Anti‐topoisomerase I (anti‐topo I) antibody and anti‐RNA polymerase III were negative, but anti‐centromere antibody was positive in an enzyme‐linked immunosorbent assay. Anti‐Ku antibody was positive in an immunoprecipitation assay using extracts of the leukemia cell line K562. Therefore, the patient was diagnosed with diffuse cutaneous systemic sclerosis with anti‐Ku and anti‐centromere antibodies. Treatment with an oral antiplatelet agent, vitamin E, a proton pump inhibitor, and i.v. lipoprostaglandin E1 were started. Subsequently, there has been repeated recurrence of finger ulcers, but no muscle involvement has been detected since his first visit. This is the first reported case of systemic sclerosis with anti‐Ku and anti‐centromere antibodies.