Soluble ICAM-1 serum levels in patients with intermediate uveitis

Aim-To investigate whether serum levels of soluble intercellular adhesion molecule 1 (sICAM-1) can serve as a marker of the presence of systemic disease in intermediate uveitis. Methods-In a multicentre study sICAM-1 serum levels were measured in 61 patients with idiopathic intermediate uveitis, controls included 56 uveitis patients with a systemic disease (26 sarcoid associated uveitis and 30 HLA-B27 positive acute anterior uveitis), 58 uveitis patients without systemic disease (30 toxoplasma chorioretinitis and 28 Fuchs' hetrochromic cyclitis), and 21 normal controls. The clinical records of the patients with intermediate uveitis were analysed for disease characteristics at the time of blood sampling and for a relation with the development of a systemic disease after a mean follow up of 4.5 years. Results-Increased serum levels of sICAM-1 were found in 34 out of 61 patients with intermediate uveitis and were significantly different when compared with toxoplasmosis, Fuchs' cyclitis, and healthy controls (p<0.001). Elevated sICAM-1 levels were also found in 18 out of 26 patients with sarcoid uveitis and in 11 out of 30 patients with HLA-B27 associated anterior uveitis. Raised sICAM-1 levels in the intermediate uveitis group were significantly associated with active ocular disease (p<0.01) and the presence of vitreous exudates (p<0.05). Increased levels of sICAM-1 correlated with interleukin 8 levels (IL-8) (tested in a previous study in the same group of intermediate uveitis patients) in patients with active systemic involvement. Follow up of the patients showed that an established or suspected systemic disease was found more often it the 21 intermediate uveitis patients with increased sICAM-1 and IL-8 levels compared with the other 40 patients with intermediate uveitis (p<0.01). Conclusions-The measurement of both sICAM-1 and IL-8 can be used as a marker for ocular disease activity and for a predisposition of developing an associated systemic disease in intermediate uveitis patients.