Objective To investigate whether high sensitivity C-reactive protein (hs CRP) levels are elevated in young type 1 diabetic patients and to determine the relationships with age, degree of metabolic control determined by glycated hemoglobin (HbA1c), blood lipids, and subclinical complications. Methods High sensitivity CRP was determined in young type 1 diabetic patients and in healthy controls. Blood lipids and HbA1c were also determined. The patients were divided into 2 groups. In group A, patients were free from subclinical complications (retinopathy, nephropathy and neuropathy) and in group B, patients had at least one subclinical complication. Results The hs CRP concentrations were significantly higher in the 126 diabetic patients (55 girls and 71 boys) than in the 52 controls (2.6+/-4mg/L vs 0.7+/-0.7mg/L; p<0.001). This difference persisted when comparing the normal subjects with the 81 patients of group A (2.0+/-3.1 mg/L; p<0.01) and the 45 patients of group B (3.6+/-5.1 mg/L; p<0.001). The hs CRP concentrations were significantly correlated with total cholesterol, total cholesterol/HDL-cholesterol ratio, and LDL cholesterol for the 2 groups of patients. In the patients of group A, significant correlations were observed between hs CRP and age or duration of diabetes. No correlation was observed between hs CRP levels and glycaemia, HbA1c and HIDL-cholesterol in the two groups of patients. Conclusion Levels of hs CRP were 3-fold greater in diabetic patients without complications than in controls and 5-fold greater in diabetic patients with subclinical complications. High sensitive CRP therefore appears to be an interesting indicator of the risk for developing complications.