“Coexistence of IgA nephropathy and renal artery stenosis in Takayasu arteritis: case report and literature review”

Although Takayasu arteritis (TAK) is a form of large vessel vasculitis, complications of glomerulonephritis have occasionally been observed, with mesangial proliferative glomerulonephritis as the most common. The aim of this work was to present a case-based review regarding the association of glomerulonephritis and IgA nephropathy (IgAN) with TAK. A literature search was carried out using the PubMed and Scopus databases for articles published in English, and the Ichu-shi Web for Japanese. A 34-year-old Japanese man was evaluated for proteinuria, and IgAN was diagnosed by renal biopsy. Simultaneously, aortic wall thickening and right renal artery stenosis confirmed a coexisting TAK. Prednisolone and methotrexate improved both diseases, and percutaneous transluminal renal angioplasty resulted in right renal artery reopening. Our case and literature review revealed that membranous proliferative glomerulonephritis and IgAN are common in eastern Asia, while focal segmental glomerulosclerosis and mesangial proliferative glomerulonephritis are common in other regions. The incidence of IgAN is higher in TAK cases and is mostly reported in Asia. Abdominal aortic involvement and renal artery stenosis are common in cases with preceding TAK. IgAN could be related to the cytokine network involving interleukin-6, suggesting the usefulness of tocilizumab in patients with TAK accompanied by IgAN. The type of glomerulonephritis complicated with TAK differs among regions, and patients with TAK are more likely to experience IgAN than the healthy population.