Progressive Renal Dysfunction due to IgG4-Related Kidney Disease Refractory to Steroid Therapy: A Case Report

Abstract

Recently, as the number of case reports of IgG4-related kidney disease (IgG4-RKD) has increased, the histopathological features and clinical approach have been clarified. IgG4-RKD generally has a benign prognosis due to the efficacy of steroid therapy and rarely requires dialysis. Herein, we report a case of IgG4-RKD that presented with a subacute onset, advanced to end-stage kidney disease, and finally required maintenance hemodialysis despite steroid therapy. A 75-year-old man was admitted to our hospital for further evaluation of subacute renal failure. Diffuse enlargement of the kidney on computed tomography and increased urinary N-acetyl-β-D-glucosaminidase and α1-microglobulin levels led us to suspect IgG4-RKD. Upon admission, the laboratory serological findings were as follows: creatinine 3.3 mg/dL, urea nitrogen 46.9 mg/dL, and IgG4 235 mg/dL. Urinalysis showed slight proteinuria without hematuria. Percutaneous renal needle biopsy showed diffuse infiltration of abundant lymphocytes and IgG4-positive plasma cells and storiform fibrosis, which is specific to IgG4-RKD, in the interstitium on light microscopy. Slight linear deposition of C3 was also observed in the tubules on immunofluorescence microscopy, with no electron-dense deposits. He was definitively diagnosed as having IgG4-RKD and started on prednisolone 0.6 mg/kg/day. However, the renal insufficiency continued to progress and hemodialysis was necessary. As the prednisolone was tapered, renal function did not improve and maintenance hemodialysis was started. In conclusion, this case indicates that the prognosis of IgG4-RKD is not necessarily benign and that further studies involving more patients are needed.

IgG4-related nephritis and interstitial pulmonary disease complicated by invasive pulmonary fungal infection: a case report

“…Since kidney involvement was firstly reported in a patient with IgG4-RD in 2004 [ 22 ], many similar cases have been described [ 23 – 25 ]. A cross-sectional study reported in 2010 revealed all kidney lesions were associated with extrarenal disease among 114 patients with IgG4-related disease [ 26 ].…”

“…Several clinicopathologic studies reported IgG4-RD with both kidney and lung involvement [ 5 , 14 , 27 – 30 ]. In kidney its characteristic manifestation is TIN with multiple extrarenal tissue damage [ 14 , 31 ], which is easily apparent with a chronic or rapid progressive renal function decline [ 23 ]. In lung, this may present as nodules with spiculated margins mimicking primary pulmonary malignancy [ 28 , 32 ], multiple ground glass opacities (GGO) mimicking interstitial lung disease [ 14 ], alveolar interstitial type, and bronchovascular type [ 33 ].…”