Incidence and prognosis of systemic lupus erythematosus in a 35 year period in Fukushima, Japan

Background We examined the epidemiology, clinical manifestations, and prognosis of pediatric systemic lupus erythematosus (SLE) in Fukushima Prefecture, Japan over a 35 year period. Methods We collected the medical records of 37 patients diagnosed with SLE between 1977 and 2013. These children were divided into two groups. group 1 consisted of 19 patients who were diagnosed between 1977 and 1995, and group 2 consisted of 18 patients diagnosed between 1996 and 2013. The epidemiology, clinical features, and prognosis were retrospectively compared between the two groups. Results The mean number of patients per 100 000 children per year for group 1 and group 2 was 0.33 ± 0.25 and 0.35 ± 0.30, respectively. The duration from onset of symptoms to treatment in group 2 was shorter than that in group 1, but the clinical and laboratory findings at onset did not differ between the two groups. All patients were treated with prednisolone, and 17 patients in group 1 and 18 in group 2 were treated with methylprednisolone pulse therapy. The frequency of cyclophosphamide treatment decreased whereas the frequency of cyclosporine, tacrolimus and mizoribine pulse therapy increased in group 2. SLE disease activity index (SLEDAI) score at the latest follow up in group 2 was lower in group 1. The survival rate was 84% in group 1 and 100% in group 2. Conclusion The frequency and severity of SLE in group 1 were similar to those in group 2, and the prognosis of SLE in group 2 was better than that in group 1.