[Serum neopterin levels in oncology patients in intensive care]

Elevated neopterin serum levels are associated with diseases that stimulate the cellular immune response. This includes viral infections, autoimmune diseases, transplant rejection and dissemination of certain types of cancer. T-helper lymphocytes and macrophages play a key role in neopterin synthesis. The degree of activation of Th1-lymphocytes is responsible for the production of interferon-gamma and interleukin-2, which stimulate neopterin production in human macrophages.

We have designed a prospective observational study to assess the dynamics of serum neopterin levels in 75 oncological patients during post-surgery period. We measured serum neopterin by means of RIA method (radioimmunoassay) in 50 uncomplicated surgery patients (group A), in 15 complicated surgery patients (group B--abdominal sepsis, peritonitis, ileus) and 10 medical ICU patients (group C). Serum levels of neopterin were measured in 5 consecutive periods: before surgery, after surgery, and on the 1st, 2nd, 3rd postoperative days.

In all groups, we observed gradual elevation of serum neopterin. The lowest values of neopterin were measured in group A in patients with uncomplicated course following surgery: 6.75 nmol/l, 7.67 nmol/l, 8.9 nmol/l, 10.82 nmol/l and 13.66 nmol/l. A significant increase in serum neopterin levels was measured in group B in patients with septic complications during perioperative period: 18.9; 23.2; 26.82; 29.53 and 27.32 nmol/l. High values of neopterin were also measured in medical ICU patients with disseminated cancer and sepsis during ICU stay: 26.1; 58.1; 28.7 and 22.5 nmol/l. We concluded that serum neopterin levels were increased during the post-surgery period. We observed a significant increase in serum neopterin in patients with severe systemic infection or sepsis or in patients with cancer progression or dissemination (more than 15-20 nmol/l). Neopterin is a simple, reliable and sensitive parameter of cell-mediated immunity, suitable for early diagnosis of viral, autoimmune and transplantant rejection diseases. Neopterin can be used also for non-specific laboratory monitoring of cancer progression and/or dissemination. (Tab. 3, Fig. 4, Ref. 7.)