Plasma interleukin-18 levels in chronic renal failure and continuous ambulatory peritoneal dialysis.
OBJECTIVE
Based on associations of interleukin (IL)-18 with chronic inflammation, we investigated IL-18, IL-6, and tumor necrosis factor-alpha (TNF-alpha) in patients with chronic renal failure (CRF) and patients undergoing continuous ambulatory peritoneal dialysis (CAPD).


METHODS
Plasma was evaluated by ELISA methodology in 15 healthy controls, 27 CRF and 15 CAPD patients.


RESULTS
Plasma IL-18 levels in CRF (572.5 +/- 41.9 pg/ml) or CAPD (479.2 +/- 47.4 pg/ml) were significantly higher than normal (263.6 +/- 20.0 pg/ml), but there was no difference in IL-18 between CRF and CAPD patients. The IL-18 concentration negatively correlated with creatinine clearance (Ccr). However, the duration of dialysis, normalized protein nitrogen appearance, weekly Ccr, and Kt/V(urea) were not correlated with plasma IL-18 in CAPD. The plasma IL-18 concentration was positively correlated with TNF-alpha but not with IL-6 in renal failure patients with or without CAPD.


CONCLUSIONS
Uremia is the principal origin of increased plasma IL-18 in these patients. Increased IL-18 levels may be associated with Th1 differentiation and elevated TNF-alpha.
Chiang
Chih-Kang
CK
Department of Internal Medicine, Far Eastern Memorial Hospital, Taipei, Taiwan.
Hsu
Shih-Ping
SP
Pai
Mei-Fen
MF
Peng
Yu-Sen
YS
Ho
Tai-I
TI
Liu
Shing-Hwa
SH
Hung
Kuan-Yu
KY
Tsai
Tun-Jun
TJ
Hsieh
Bor-Shen
BS
D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007249:Inflammation / Q000175:diagnosis; D020382:Interleukin-18 / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy*; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D014511:Uremia / Q000276:immunology
D015415:Biomarkers; D020382:Interleukin-18; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha