In this thesis the protein YKL-40 was evaluated regarding its possible benefit for the diagnosis of various diseases. In two studies with different patient cohorts the YKL-40 concentration was determined using an immunoassay system. Serum levels were evaluated with respect to the diagnostic value for the different underlying diseases and compared to the CRP concentration of these patients. YKL-40 revealed additional value as a humoral marker of inflammation. For the diagnosis of pneumonia within a cohort of inflammatory diseases, YKL-40 is superior to CRP.
«