ABSTRACT:A 56-year-old man who had undergone cadaveric kidney transplantation 21 months earlier was admitted to our hospital for a protocol biopsy; he had a serum creatinine level of 1.2 mg/dL and no proteinuria. Histological features showed two distinct entities: (i) inflammatory cell infiltration, in the glomerular and peritubular capillaries and (ii) focal, aggressive tubulointerstitial inflammatory cell infiltration, predominantly plasma cells, with mild tubulitis (Banff 13 classification: i2, t1, g2, ptc2, v0, ci1, ct1, cg0, cv0). Immunohistological studies showed mildly positive C4d immunoreactivity in the peritubular capillaries. The patient had donor specific antibody to human-leucocyte-antigen-DR53. We diagnosed him with subclinical antibody-mediated rejection accompanied by plasma cell-rich acute rejection. Both antibody-mediated rejection due to anti-human-leucocyteantigen -DR53 antibodies and plasma cell-rich acute rejection are known to be refractory and have a poor prognosis. Thus, we started plasma exchange with intravenous immunoglobulin and rituximab for the former and 3 days of consecutive steroid pulse therapy for the latter. Three months after treatment, a follow-up allograft biopsy showed excellent responses to treatment for both histological features. This case report considers the importance of an early diagnosis and appropriate intervention for subclinical antibody-mediated rejection due to donor specific antibody to humanleucocyte-antigen-DR53 and plasma cell-rich acute rejection.A recent study demonstrated that untreated subclinical antibody-mediated rejection (ABMR) is an important predictor of poor allograft outcomes.

We report a rare case of nephrocalcinosis caused by hereditary renal hypouricaemia 3 months after kidney transplantation. A 41-year-old man who underwent living-related kidney transplantation from his father was admitted to our hospital for a protocol biopsy; he had a serum creatinine (S-Cr) of 1.37 mg/dL and no proteinuria. Histologically, there was no evidence of rejection or calcineurin inhibitor toxicity, although scattered nephrocalcinosis was observed in the distal tubules. Perioperatively, the patient had a serum uric acid (S-UA) of 1.9 mg/dL with a fractional excretion of uric acid (FEUA) of 29% (normal, <10%) and UA clearance of 26.8 mL/min (normal, 7.3-14.7 mL/min) 3 days after kidney transplantation. The donor also had a relatively low S-UA of 2.4 mg/dL and high FEUA of 10.3%. Subsequent DNA direct sequencing followed by restriction fragment length polymorphism revealed that both the recipient's and donor's urate transporter 1 (URAT1) gene had a heterozygous nonsense mutation in exon 5 (C889T). Further, the immunoreactivity of antibodies for the C terminus of URAT1 revealed a partial deletion. De Galantha and von Kossa staining revealed that the nephrocalcinosis was due to urate crystals and calcium stones. Therefore, we diagnosed hereditary renal hypouricaemia. We directed the patient to avoid hard exercise, drink plenty of water, and alkalize the urine. The 1-year follow-up allograft biopsy showed no evidence of nephrocalcinosis in the distal tubules. This is the first report of nephrocalcinosis in the distal tubules as a diagnostic clue to hereditary renal hypouricaemia. We also review the related literature.

The long-term patient and graft survival of IgA vasculitis in renal transplantation were comparable with the previous reports. The recurrence rate was 28.6 %, but none of the recurrent cases showed allograft loss in this study. We speculate that methylprednisolone pulse therapy and/or tonsillectomy prevent the progression of recurrent IgA vasculitis.

ABSTRACT:We report a case of recurrent Henoch-Schönlein purpura nephritis (HSPN) treated successfully with a tonsillectomy and steroid pulse therapy in a kidney transplant patient. A 29-year-old woman was admitted to our hospital for an episode biopsy; she had a serum creatinine (S-Cr) of 1.0 mg/dL and 1.34 g/day proteinuria 26 months after kidney transplantation. Histological examination revealed increased amounts of mesangial matrix and mesangial hypercellularity with IgA deposition. Of note, one glomerulus showed focal endocapillary proliferation and tuft necrosis. We diagnosed active recurrent HSPN. Considering both the histological findings and refractory clinical course of the native kidney, she was treated for 3 consecutive days with steroid pulse therapy and a tonsillectomy. The patient's proteinuria decreased gradually to less than 150 mg/day 6 months later. A second biopsy 6 years after kidney transplantation showed an excellent response to treatment and revealed a marked reduction in both the mesangial matrix and mesangial hypercellularity, with trace IgA deposition. We conclude that a tonsillectomy and steroid pulse therapy appeared to be useful in this patient with active recurrent HSPN. This paper is the first to report a tonsillectomy and steroid pulse therapy as a therapeutic option for active recurrent HSPN. Further studies are needed to elucidate the efficacy and mechanisms of tonsillectomy with recurrent HSPN in kidney transplant patients.Henoch-Schönlein purpura is a systemic small vessel vasculitis thought to be mediated by IgA immune complex deposition (IgA vasculitis). Henoch-Schönlein purpura affects the kidney in 20-80% of patients and most patients have a good prognosis. However, 3-20% of Henoch-Schönlein purpura nephritis (HSPN) has a poor outcome with a higher incidence of endstage renal disease, especially in adults. [1][2][3] Compared with IgA nephropathy, relatively little is known about recurrent HSPN in renal allografts. The recurrence rate ranges from 15% to 53%, and graft loss due to recurrent HSPN was 7.5% to 21% in different observation periods. 4 Therapy for severe HSPN usually involves methylprednisolone pulse therapy with oral corticosteroids, immunosuppressive agents, antiplatelet drugs, and plasmapheresis. Tonsillectomy has also been used in some HSPN patients, with a marked improvement in renal function and proteinuria, 3,5 but its benefit in the setting of recurrent disease in a renal allograft has not been reported. To our knowledge, this is the first report of the efficacy of tonsillectomy and steroid pulse therapy in a kidney transplant patient who developed active HSPN. CASE REPORTA 29-year-old Japanese woman was admitted to our hospital for an episode biopsy 26 months after kidney transplantation. She first presented with purpura on her lower legs, abdominal pain, macrohematuria, and proteinuria (0.5-1.0 g/ day) at 15 years of age, at which time a renal biopsy was performed and the histology revealed focal segmental

BackgroundBoth prevention and treatment of recurrent immunoglobulin A nephropathy (IgAN) in kidney transplant recipients are important since recurrent IgAN seems to affect long-term graft survival. We present here a case of recurrent IgAN that was successfully treated using steroid pulse therapy plus tonsillectomy 10 years after kidney transplantation.Case presentationA 46-year-old male was admitted for an episode biopsy with a serum creatinine level of 1.8 mg/dl and proteinuria (0.7 g/day). Histological features showed recurrent IgAN (only focal segmental mesangial proliferation) and severe arteriolar hyalinosis partly associated with calcineurin inhibitor toxicity, with limited interstitial fibrosis and tubular atrophy (5%) (IF/TA) 8 years after transplantation. Sodium restriction and conversion from cyclosporine to tacrolimus successfully reduced his proteinuria to the level of 0.15 g/day. However, 2 years later, his proteinuria increased again (1.0 g/day) and a second episode biopsy showed global mesangial proliferation with glomerular endocapillary and extracapillary proliferation accompanied by progressive IF/TA (20%). The steroid pulse therapy plus tonsillectomy successfully decreased his proteinuria and he achieved clinical remission 3 years after this treatment.ConclusionThis case, presented with a review of relevant literature, demonstrates the difficulty and importance of the treatment of recurrent IgAN and calcineurin inhibitor arteriolopathy, especially in long-term kidney allograft management.