ABSTRACT
BACKGROUND: Neopterin is a pyrazino-pyrimidine compound, produced by human monocytes or macrophages primarily upon stimulation with gamma interferon. Neopterin is a marker associated with cell- mediated immunity. The levels of neopterin in body fluids are elevated in allograft rejection, infections, autoimmune diseases, malignancies, cardiac and renal diseases. We hypothesized that the levels of serum and urine neopterin maybe elevated in some renal disease including nephrotic syndrome (NS), chronic renal failure (CRF) and end stage renal disease (ESRD). METHODS: We examnined the serum and urinary neopterin levels in 19 patients with NS underwent renal biopsy, 8 patients with CRF, 64 patients with ESRD undergoing maintenance hemodialysis. Twenty-two healthy controls were enrolled to define the normal range of neopterin levels. Serum and urinary neopterin were measured by radiommunoassay method. We also correlated the levels of serum and urinary neopterin with many clinical parameters such as WBC, hemoglobin, hematocrit, BUN, creatinine, total protein, albumin, triglyceride, iron, total iron binding capacity. RESULTS: The serum neopterin levels elevated in patients with NS (14.1+/-30.9 ng/mL), CRF (28.2+/-19.4 ng/mL) and ESRD (68.6+/-25.5 ng/mL) than control (1.6+/-0.3 ng/mL). Particularly the patients with CRF and ESRD showed statistically significant elevation (p<0.05, p<0.01). The urine neopterin levels elevated in patients with NS (203.2+/-349.6 microgramol/mol creatinine), CRF (319.2+/-107.7 microgramol/mol creatinine) and ESRD (407.9+/-256.9 microgramol/mol creatinine) than control (108.9+/-57.9 microgramol/mol creatinine). Particularly the patients with CRF and ESRD showed statistically significant elevation (p<0.05, p<0.05). The serum neopterin showed significantly positive correlation with serum creatinine levels, inverse correlation with total iron binding capacity and serum triglyceride levels among clinical parameters in all groups (respectively p<0.01). The urine neopterin showed significant inverse correlation with hemoglobin (p< 0.05). CONCIUSION: The serum and urinary neopterin levels elevated in patients with some renal diseases. And also neopterin levels showed clinical correlations with some renal parameters in these patients. We suggest that serum and urinary neopterin levels may be useful marker to predict disease acitivity and prognosis in some renal diseases. They should be confirmed by a prospective study during a long-lasting and in a higher number of patients.