Tumour necrosis factor does not increase during routine cuprophane haemodialysis in healthy well-nourished patients

Serum tumour necrosis factor (TNF) was measured by both bioassay and immunoassay (ELISA) during routine cuprophane acetate haemodialysis in 17 asymptomatic patients. In 14 (82%) there was no change in the serum values during haemodialysis. TNF was found to increase, using both assays, in three patients, the responders. These patients differed from the others in terms of body mass index, mean index 16.8 kg/m2 (range 14.8-18.2), compared to the non-responders, mean 24.1 kg/m2 (range 19.6-33.1), P less than 0.05, and had an increased serum calcium, mean 2.9 mmol/l (range 2.6-3.2) compared to the non-responders, mean 2.4 mmol/l (range 1.7-2.8), P less than 0.05. Two of the TNF responders subsequently died of cachexia and respiratory infection. The third underwent a successful parathyroidectomy, and when retested after an increase in body-weight with a normal serum calcium concentration no longer showed an increase in TNF during haemodialysis.