[Development and long-term prognosis of unexplained persistent inflammatory biologic syndromes]

Unexplained inflammatory syndrome is a frequent and worrying condition in Internal Medicine. However, the long-term clinical outcome of these patients cannot be inferred from the literature. The aim of this study is to describe the long-term follow-up and the prognosis of a group of patients hospitalised for an inflammatory syndrome and discharged without causal diagnosis.

This retrospective study was carried out on 46 patients, 15 men and 31 women, aged 21 to 90 years, hospitalised between 1992 and 1999. Data concerning the hospital stay were obtained from the patients' medical record. Follow-up was performed by consulting the treating physician.

The prognosis of these patients is fairly good. In one third of the cases, the inflammatory syndrome resolved spontaneously (n = 13). In the second third, a definite diagnosis was established after discharge (n = 14) and consisted mainly of chronic inflammatory diseases (n = 9), cured with a specific treatment. In the remaining third (n = 12), the inflammatory syndrome persisted, in clinically asymptomatic patients.

These results suggest that the persistence of an inflammatory syndrome is not a poor prognostic factor. Thus we propose for patients discharged with an undiagnosed persistent inflammatory syndrome despite thorough investigations, a simple clinical and biological follow-up instead of repeated etiological investigations.