Serum cytokine profile in reflux nephropathy

Cytokines are small regulatory peptides with diverse functions. They regula te the immune system and modulate the inflammatory response, both of which are implicated in vesico-ureteric reflux (VUR) and associated reflux nephro pathy (RN). The cytokine profile in VUR and RN has yet to be fully investig ated. Blood was obtained from three subject groups immediately after induct ion of anaesthesia: group A [subjects with VUR and established RN, (N = 9)] ; group B [VUR alone but no associated RN, (N = 6)]; and group C [age- and sex-matched controls with no history of urinary sepsis, (N = 14)]. Serum cy tokine levels of tumour-necrosis factor-alpha (TNF-alpha), interleukin-6 (I L-6), soluble TNF receptor-1 (sTNF-R1), and interleukin-8 (IL-8) were measu red using standard ELISA technique. Serum levels of IL-6 were higher in gro up A subjects (1.798-4.638 pg/ml, median 3.253 pg/ml) than controls (1.531- 2.078 pg/ml, median 1.798 pg/ml). There was no significant difference in le vels in group B subjects (1.498-3.048 pg/ml, median 1.948 pg/ml) and contro ls. These same relationships were observed for levels of TNF-alpha (group A : 8.501-14.471 pg/ml, median 13.483 pg/ml; group B: 7.088-10.650 pg/ml, med ian 8.886 pg/ mi; group C: 6.746-13.344 pg/ml, median 7.671 pg/ml) and sTNF -R1 (group A: 690.34-5780.74 pg/ml, median 1197.38 pg/ml; group B: 366.65-1 401.62 pg/ml, median 592.82 pg/ml; C: 313.49-636.33 pg/ml, median 504.17 pg /ml). IL-8 was not significantly elevated in any of the study groups (A or B) compared with control group C (group A: 27.08-56.38 pg/ml, median 31.35 pg/ml; group B: 29.90-35.87 pg/ml, median 31.35 pg/ml; group C: 25.05-30.22 pg/ml, median 29.90 pg/ml). These results suggest there may be an immunolo gical basis to RN.