The Association between High-Dose Allopurinol and Erythropoietin Hyporesponsiveness in Advanced Chronic Kidney Disease: JOINT-KD Study.

INTRODUCTION: The aim of the study was to explore the association between urate-lowering agents and reduced response to erythropoietin-stimulating agents in patients suffering from chronic kidney disease G5. METHODS: We conducted a cross-sectional, multicenter study in Japan between April and June 2013, enrolling patients aged 20 years or older with an estimated glomerular filtration rate of ≤15 mL/min/1.73 m2. Exclusion criteria encompassed patients with a history of hemodialysis, peritoneal dialysis, or organ transplantation. The patients were categorized into four groups based on the use of urate-lowering drugs: high-dose allopurinol (>50 mg/day), low-dose allopurinol (≤50 mg/day), febuxostat, and no-treatment groups. We used a multivariable logistic regression model, adjusted for covariates, to determine the odds ratio (OR) for erythropoietin hyporesponsiveness, defined by an erythropoietin resistance index (ERI) of ≥10, associated with urate-lowering drugs. RESULTS: A total of 542 patients were included in the analysis, with 105, 36, 165, and 236 patients in the high-dose allopurinol, low-dose allopurinol, febuxostat, and no-treatment groups, respectively. The median and quartiles of ERIs were 6.3 (0, 12.2), 3.8 (0, 11.2), 3.4 (0, 9.8), and 4.8 (0, 11.2) in the high-dose allopurinol, low-dose allopurinol, febuxostat, and no-treatment groups, respectively. The multivariate regression model showed a statistically significant association between the high-dose allopurinol group and erythropoietin hyporesponsiveness, compared to the no-treatment group (OR = 1.98, 95% confidence interval: 1.10-3.57). CONCLUSIONS: Our study suggests that the use of high-dose allopurinol exceeding the optimal dose may lead to hyporesponsiveness to erythropoiesis-stimulating agents.

Granulomatosis with polyangiitis in a patient with a thoracic vertebral lesion: a case report.

Granulomatosis with polyangiitis is a systemic, small vessel vasculitis associated with the anti-neutrophil cytoplasmic antibody. We herein report a case of granulomatosis with polyangiitis with paravertebral lesions. A 69-year-old man presented to our hospital with fever, back pain, and myalgia. A computed tomography scan showed multiple lung nodules, while magnetic resonance imaging revealed soft tissue shadows around a thoracic vertebral lesion. A laboratory examination revealed positive myeloperoxidase anti-neutrophil cytoplasmic antibody. He was diagnosed with granulomatosis with polyangiitis. He was treated with oral glucocorticoid and intravenous cyclophosphamide, and the shadows resolved. Physicians should consider granulomatosis with polyangiitis in cases with paravertebral lesions.