While the knowledge concerning the role of the immune system in many internal 
disorders has grown rapidly in recent years, there are few methods to assess 
immune system activation in clinical practice. Measurement of urine neopterin, 
product of a metabolic pathway controlled by interferon-gamma, has been found 
useful in many clinical conditions. The present study concerns neopterin 
excretion in 157 patients with different internal disorders. As expected, we 
found an increase in urine neopterin in patients with malignant tumors, 
autoimmune disorders like systemic lupus erythematosus or inflammatory bowel 
disease, and infections. Elevated neopterin levels were also observed in acute 
pancreatitis and in acute myocardial infarction. In addition, significant 
correlations between urine neopterin and zinc and neopterin and copper excretion 
were found suggesting a physiological role of neopterin as urine antioxidant.