Castleman disease (CD), a benign lymphoproliferative disorder, can involve kidney. Various diseases had been reported in patients with CD, amyloidosis, thrombotic microangiopathy being the most common. Zoshima et al. reported 2 cases of CD with kidney involvement mimicking IgG4-related tubulointerstitial nephritis. Although kidney biopsies show many IgG4+ plasma cells, there was no characteristic storiform fibrosis or IgG staining in tubular basement membrane as seen in majority patients with IgG4 renal disease. Patients with CD had more marked inflammatory response with highly elevated C reactive protein and were not responsive to steroid as favorably as IgG4RD. Imaging study was also different with CD showing no kidney abnormalities in contrast to characteristic low density lesion in IgG4RD.
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| Patchy plasma cell aggregates without storiform fibrosis in Castleman disease with tubulointerstitial nephritis (Image from Zoshima et al.) |
Zoshima T, Yamada K, Hara S, et al. Multicentric Castleman Disease With Tubulointerstitial Nephritis Mimicking IgG4-related Disease: Two Case Reports. Am J Surg Pathol. 2016;40(4):495-501. doi:10.1097/PAS.0000000000000575
