Introduction to the special issue on the 9th International Congress on Autoimmunity.

It is a great pleasure to introduce this special issue of Immunologic Research on the 9th International Congress on Autoimmunity held in Nice, France, on March 26–30, 2014. This special edition highlights a broad spectrum of emerging issues in the field of autoimmune diseases, both through original studies, reviews and case reports. Nice area and most particularly Grasse (France) might be the sweetest smelling city in Europe, widely known as the perfume capital in the world. While a superior olfactory sense, like that of Jean Baptiste Grenouille, the antihero of Patrick Süskind’s novel Perfume, may lead to addiction and psychiatric diseases, some olfactory function has been found to be impaired in patients affected by variety of autoimmune diseases. Recently, several studies have reported olfactory disorders in various immune-mediated diseases [1] including systemic lupus erythematosus (SLE) [2]. In this issue, two articles evaluate for the first time olfactory function in patients with idiopathic inflammatory myopathies (IIM) [3], fibromyalgia (FM) and systemic sclerosis (SSc) [4]. Thus, Iaccarino et al. [3] performed a case–control study in 60 patients with IIM using the Sniffin’ Sticks test, based on threshold, discrimination and identification (TDI) of odors. TDI score was found to be significantly lower in IIM patients when compared to ageand sex-matched healthy control individuals. Similarly, Amital et al. [4] investigated olfactory function in 24 patients with FM compared to 20 SSc and age-matched healthy controls. They demonstrated that TDI score was significantly decreased in FM and SSc compared with controls, the sense of smell being more deeply altered in patients with FM. The mechanisms of smell system damage in patients with autoimmune diseases are still elusive and are though to result from a complex interplay between genetic, environmental and hormonal factors [1]. In both articles, the role of depression as a potential confounding factor is still unclear. Unfortunately, none of these studies explored potential pathophysiological processes. Whether olfactory function may parallel disease activity or outcome should also be explored. Many women report a heightened sense of smell during pregnancy. Accounts of these anecdotes have existed for over 100 years, but scientific evidence has been sparse and inconclusive. A recent review [5] examined the literature on olfactory perception during pregnancy, showing no support for a general decrease in olfactory thresholds. This special issue examined more conventional aspects of pregnancy in the context of autoimmunity. Two authors have questioned predictive factors of SLE flares as well as of obstetric and fetal complications during pregnancy [6, 7]. Despite considerable progress in the identification of pre-conception, per pregnancy and puerperium risk factors for lupus flare, summarized by Jara et al. [7], it appears that predictive factors in pregnancy have not been systematically and fully elucidated. However, by prospectively following 132 pregnancies in 96 SLE patients, Borella et al. [6] reported that the number of flares before conception best predicted the risk of lupus flares during pregnancy. Moreover, manifestations during flares were even best predicted by the same features occurred before conception, illustrating Thucydides’ quote ‘‘History eternally repeats itself.’’ E. Rosenthal (&) M. Versini P.-Y. Jeandel Department of Internal Medicine, Centre Hospitalier Universitaire de Nice, Université de Nice Sophia Antipolis, 06200 Nice, France e-mail: [email protected]