Gadolinium-based contrast agents, erythropoietin and nephrogenic systemic fibrosis in patients with end-stage renal failure

Choi JH et al. Vitamin E improves microsomal phospholipase A2 activity and the arachidonic acid cascade in kidney of diabetic rats. Gadolinium-based contrast agents, erythropoietin and nephrogenic systemic fibrosis in patients with end-stage renal failure Sir, Nephrogenic systemic fibrosis (NSF) is a rare and debili-tating disorder, which affects patients with kidney failure. An association with gadolinium-based contrast agents for magnetic resonance imaging (MRI) was found [1]. However , not all NSF patients had a prior gadolinium exposure [2]. Recently, an association of NSF and the use of erythropoietin was proposed [3]. Our aim was, thus, to investigate the use of gadolinium-based contrast agents and erythropoietin in haemodialysis patients with and without NSF. Four patients in our dialysis unit developed NSF (between 2002 and 2006). We retrospectively compared those to all other patients requiring chronic haemodialysis (n = 61; data collection in August 2007). Besides demographic characteristics, we investigated haemoglobin levels , iron and erythropoietin supplementation, parameters of inflammation, Kt/V and exposure to gadolinium. Table 1 gives the basic characteristics of patients and controls. There were no differences with regard to age, sex, number of previous kidney transplantations, cumulative time on haemodialysis or primary renal disease. The same was true for Kt/V. The haemoglobin levels were comparable , but NSF patients received higher doses of erythro-poietin (331.1 ± 215.1 versus 133.3 ± 99.5 U/week/kg body weight; P < 0.05). In the NSF group, 4/4 of the patients received erythropoietin and in the control group 53/61 (P > 0.05). In the NSF group, on average, more contrast enhanced MRIs had been performed [3.0 ± 1.2 per patient (range 2–4) versus 1.8 ± 2.0 per patient (range 0–10); the mean dose contrast agent 12.6 ± 5.4 versus 11.6 ± 4.6 mmol/MRI]. In the control group, the following contrast agents were used: gadopentetate dimeglumine 94 times, gadodiamide 9 times, gadobutrol 4 times and gadobenate dimeglumine once. In the NSF group, gadopentetate dimeg-lumine and gadodiamide were used six times each. The cumulative dose of contrast agent was higher in the NSF group (0.57 ± 0.14 versus 0.29 ± 0.37 mmol/kg body weight; P < 0.05). In the NSF group, the time from the last administration of a contrast agent to the first symptoms was 2 weeks till 5 months. Comparing those patients with a minimum of two MRIs (as this is the minimum number in the NSF group) patients in the NSF group, again, received …