IgG4-related Kidney Disease Mimicking Malignant Ureter Tumor

Abstract

Immunoglobulin G4-related disease is a recently recognized systemic disease that can affect any organ or tissue in the body, including the kidneys. IgG4-related kidney disease (IgG4-RKD) is an important part of immunoglobulin G4-related disease. The most common renal manifestation of IgG4-RKD is tubulointerstitial nephritis and glomerular lesions. There, however, is few case of IgG4-RKD mimicking malignant ureter tumor leading to severe hydronephrosis. We herein report an unusual case of IgG4-RKD mimicking malignancy.A 66-year-old Asian man presented to the nephrologist with soreness of loins, anorexia, and acute kidney injury in 2010. His renal function spontaneously improved after 2 weeks’ hemodialysis without systemic steroid therapy. Four years later, he presented to the urologist with severe left hydronephrosis because of marked thickness of the left ureter wall. As a ureteral malignancy could not be ruled out, laparoscopic nephroureterectomy was performed.IgG4-related kidney disease was confirmed by the histologic examination. Then, repeat laboratory test showed almost complete recovery of renal function after initiation of steroidal therapy.This case highlights the rare possibility of IgG4-RKD mimicking malignant ureter tumor. Nephrologist and pathologists should be aware of the possibility that hydronephrosis with ureter obstruction may be involved in IgG4-RKD.

IgG4-related focal retroperitoneal fibrosis in ureter suggestive of colon cancer recurrence and resected laparoscopically: a case report

“…To our knowledge, the published literature concerning IgG4-RD occurring in ureters is rare, with only 13 cases found globally in our survey. All cases including ours are summarized in Table 1 [10][11][12][13][14][15][16][17][18], which shows that 11 (78.6%) were men and 3 (21.4%) were women. The median patient age was 74 years (range, 39-84 years).…”

A case of IgG4-related kidney disease with predominantly unilateral renal atrophy

“…In general, rapid unilateral renal atrophy is caused by renal arterial stenosis, renal infarction, thromboembolism, or hydronephrosis associated with periaortitis or inflammatory abdominal aortic aneurysm [ 15 , 16 ]. Moreover, unilateral renal atrophy could be induced by unilateral hydronephrosis in cases with IgG4-related periaortitis/retroperitoneal fibrosis [ 10 , 11 ]. However, this is the first reported case with IgG4-RKD to show multiple low-density lesions in the bilateral kidneys on CE-CT and obvious unilateral renal atrophy without retroperitoneal fibrosis or hydronephrosis.…”

“…Patients with IgG4-related kidney disease (IgG4-RKD) reveal various renal abnormalities on imaging studies, such as multiple low-density lesions on contrast-enhanced computed tomography (CE-CT), diffuse bilateral renal swelling, and/or a hypovascular solitary nodule [ 6 , 7 ], resulting in partial or diffuse renal atrophy in some cases [ 8 , 9 ]. However, unilateral renal atrophy is very rare except in cases of unilateral hydronephrosis caused by IgG4-related retroperitoneal fibrosis [ 10 , 11 ]. Here, we describe a patient with IgG4-RKD manifesting predominantly unilateral renal atrophy probably due to IgG4-related tubulointerstitial nephritis (IgG4-related TIN).…”

Simulators of Urothelial Carcinoma

“…IgG4-related disease is a systemic autoimmune disorder that may affect many different organs and whose pathophysiological bases and intimate mechanisms are still badly known [54]. The urinary tract, from renal pelvis to urethra [55][56][57][58][59][60], is frequently involved. IgG4-related disease simulates malignancy everywhere, since it develops tumor masses that are detectable on radiological exams.…”