Background The effect of dialysis on urate levels (sUA) in patients with gout has not been well characterized. No prospective series are available from the literature, and no recommendation has yet been made by either EULAR or ACR on the topic.
Methods Exploratory, observational, prospective study. Patients with crystal-proven gout and at least one flare the previous year to entrance into dialysis program, either hemodialysis (HD) or home peritoneal dialysis (PD), were followed-up. No urate-lowering drug was prescribed for the first 3-month period, but low-dose allopurinol (50 mg/day) was to be prescribed from 6-month visit onwards if tophi (any subcutaneous or ultrasonographic >10 mm longest diameter) were present or febuxostat in case allopurinol was not clinically suitable. sUA levels previous to the first dialysis procedure were recorded, along with sUA levels pre-dialysis (pre-sUA) and immediately post-dialysis (for patients on hemodialysis) sUA (post-sUA) were obtained during follow-up at 3, 6, and 12 months of follow-up. No prophylaxis was prescribed, and only adrenocorticotropic hormone (ACTH) analogue or corticosteroids were to be used for the treatment of flares.
Results 17 patients studied to date: 12 men, mean age 69 (IQ range 62–78). Time from onset of gout was 7years (IQR 1–10) pre-dialysis, and 2 patients entered into dialysis due to prolonged use of NSAIDs because recurrent, longstanding gout over 20 years. Allopurinol (n=6) and febuxostat (n=2) had been prescribed previously to dialysis procedures. ULT was prescribed to 10 patients: 4/4 patients on PD and 6/13 on HD as per in methods; patients treated were prescribed allopurinol 50 mg/day but one who showed HLA-B58 antigen and was treated with febuxostat 80 mg every 3 days. After 12 months 5 patients were lost for follow-up: 2 underwent a renal transplant, 3 were dialyzed at private centers. Follow-up ranged from 12 to 30 months.
There was a significant reduction in sUA at 3-month (Δ - 2.6 mg/dl), compared to baseline sUA. Reduction of sUA from 3–6-month and 3–12 month was greater in patients treated with ULT (Table).
The rate of flares at 3-month was similar in patients on HD (5/13) than in patients on PD (2/4), only one flare was reported at 6 month follow-up visits, none afterwards. No serious side effect was observed.
Conclusions In this exploratory study, dialysis is effective in reducing sUA levels. In hemodialysis, both sUa and postHD-sUA may be needed to better estimate the effect of interventions on sUA. Low dose ULT seems to be effective and may be considered to properly control sUA, but only to be considered in patients with severe (tophaceous) gout.
Disclosure of Interest I. Urionagüena: None declared, S. P. Chinchilla: None declared, G. Garcia Erauzkin: None declared, M. L. Muñiz-Gomez: None declared, F. Pérez-Ruiz Consultant for: Amgen, Ardea, AstraZeneca, Gruenenthal, Menarini, Speakers bureau: AstraZeneca, Gruenenthal, Menarini