Taro Sugase

Central venous stenosis among hemodialysis patients is often not associated with previous central venous catheters.

It is widely assumed that central venous stenosis (CVS) is most commonly associated with previous central venous catheterization among the chronic hemodialysis (HD) patients. We evaluated the validity of this assumption in this retrospective study. The clinical records from 2,856 consecutive HD patients with vascular access failure during a 5-year period were reviewed, and a total of 26 patients with symptomatic CVS were identified. Combined with radiological findings, their clinical characteristics were examined. Only seven patients had a history of internal jugular dialysis catheterization. Diagnostic multidetector row computed tomography angiography showed that 7 of the 19 patients with no history of catheterization had left innominate vein stenosis due to extrinsic compression between the sternum and arch vessels. These patients had a shorter period from the time of creation of the vascular access to the initial referral (9.2 ± 7.6 months) than the rest of the patients (35.5 ± 18.6 months, p = 0.0017). Our findings suggest that cases without a history of central venous catheterization may not be rare among the HD patients with symptomatic CVS. However, those still need to be confirm by larger prospective studies of overall chronic HD patients with symptomatic CVS.

Balloon-Assisted Creation and Maturation of an Arteriovenous Fistula in a Patient with Small-Caliber Vasculature

The major problem associated with the creation of an arteriovenous fistula (AVF), which is the optimal form of vascular access for hemodialysis, is the fact that fistulas do not necessarily mature into a usable vascular access, requiring subsequent revision and construction of another access. The caliber of the vessels used for fistula creation is a pivotal factor predicting the presumable maturation of the constructed fistula, and veins less than 2.5 mm in diameter have poor outcomes. This report describes the balloon-assisted creation and maturation of an autogenous radial-cephalic AVF in a patient with a small-caliber vein and a radial artery measuring approximately 2 and 1.5 mm in diameter, respectively. The clinical impact of percutaneous radiological intervention for expediting the maturation of an autogenous AVF with small-caliber vessels is also discussed.

Membranous nephropathy in an HIV-positive patient complicated with hepatitis B virus infection

In ordinary settings, human immunodeficiency virus (HIV)-associated nephropathy should be considered when HIV infection is associated with heavy proteinuria. On the other hand, hepatitis B virus (HBV) may also play a role in the development of glomerular injury among patients with HIV infection, since HIV and HBV infections commonly occur together due to shared modes of transmission. We present here a case of nephrotic syndrome in an HIV-positive patient complicated with HBV infection. A renal biopsy revealed sparse granular deposits of immunoglobulin G in the subepithelial region, consistent with membranous nephropathy (MN) stage I. Moreover, immunostaining exhibited weak anti-hepatitis B core activity within glomeruli. These results led us to consider that HBV-associated MN might play a role in the development of nephrotic syndrome. Although anti-viral treatment for patients with HBV-associated MN has been suggested to be clinically effective, the use of two anti-HIV agents (tenofovir and emtricitabine), both of which have anti-HBV activities, was not effective for the patient’s nephrotic syndrome, despite obtaining a decrease in the serum HBV-DNA levels. A lack of prospective data suggests that many decisions on the treatment of glomerulopathies with HIV infections are potentially empirical. Obviously, further studies and accumulated clinical experience are required to better determine the pathogenesis and management of HBV-associated MN among patients with HIV infections.

Therapeutic Challenges to End-Stage Kidney Disease in a Patient with Tetralogy of Fallot

In this report, we describe the case of an end-stage kidney disease patient with tetralogy of Fallot (TOF). A 33-year-old female with TOF was admitted to our hospital with complaints of general fatigue and appetite loss probably due to uremic milieu. She was ultimately treated with peritoneal dialysis (PD) with a favorable clinical course. TOF patients with chronic kidney disease are not exceptional, although the currently available information regarding the association between TOF and renal failure severe enough to require dialysis treatment is limited. We also discuss the complex processes of how and why PD was selected as a mode of chronic renal replacement therapy in this case.

Tubulointerstitial Nephritis and Uveitis Syndrome: Are Drugs Offenders or Bystanders?

A 16-year-old female patient was admitted to our hospital due to progressive renal dysfunction with an increased serum creatinine (sCr) level of 1.7 mg/dL. Her clinical course without any ocular manifestations and results of drug-induced, lymphocyte-stimulating tests, in addition to a renal histological assessment, initially encouraged us to ascribe the patients renal abnormalities to drug-induced acute interstitial nephritis (AIN). Four months later, she started to complain about reduced visual acuity when she was found to have anterior bilateral uveitis despite the recovered renal function with almost constant sCr levels around 0.7 mg/dL. Thus, a diagnosis of tubulointerstitial nephritis and uveitis (TINU) syndrome was finally made. Our case illustrates the difficulties in distinguishing late-onset uveitis TINU syndrome from drug-induced AIN at the time of the renal biopsy, thereby suggesting the importance of a longitudinal follow-up to overcome the potential underdiagnosis of the disease. Several diagnostic conundrums that emerged in this case are also discussed.

Henoch–Schönlein purpura complicated with severe gastrointestinal bleeding

Bleeding from the gastrointestinal tract is one of the common determinants of morbidity and mortality in the ordinary clinical setting. The gastrointestinal involvement of Henoch–Schönlein purpura (HSP) has often been described as self-limiting, with no long-term morbidity. In this report, we describe our experience with a male HSP patient who presented with abdominal pain, loss of appetite and deteriorated renal function associated with nephrotic syndrome. Despite the use of aggressive immunomodulatory treatments, including corticosteroids and plasmapheresis, he developed lethal gastrointestinal hemorrhage. We believe that the accumulation of more experience with additional cases similar to ours is mandatory for the establishment of optimal management for HSP patients with severe gastrointestinal manifestations.

Rituximab Treatment for PR3-ANCA-Positive Membranoproliferative Glomerulonephritis Associated with Adult-Onset Periodic Fever Syndrome

We report the case of a 36-year-old Japanese woman with nephrotic syndrome due to membranoproliferative glomerulonephritis (MPGN) Type I diagnosed after a 5-year history of periodic fever syndrome (PFS). Hypocomplementemia and elevation of anti-proteinase 3 anti-neutrophil cytoplasmic autoantibody (PR3-ANCA) were observed. HIV, and hepatitis B and C serology were negative. Nephrotic syndrome and periodic fever did not respond to oral steroid and intravenous steroid pulse therapies combined with cyclosporine, dipyridamole, warfarin and losartan. We tried immunotherapy using rituximab, a human-mouse chimeric monoclonal antibody directed against the CD20 antigen on mature B cells. This therapeutic approach led to improvement of renal function and remission of nephrotic syndrome and hypocomplementemia. However, it did not have a beneficial effect on periodic fever. Suspecting adult-onset hereditary PFS, we analyzed her genetic alteration of MEFV and TNFRSF1A genes. A rare genotype in intron 6 of TNFRSF1A was revealed. The etiological relationship between periodic fever and MPGN is discussed. Rituximab is a hopeful choice of induction therapy for refractory MPGN.

Acute Kidney Injury Associated with Renal Cell Carcinoma Complicated by Renal Vein and Inferior Vena Cava Involvement.

Acute kidney injury (AKI) is caused by diverse pathologies, although it may occasionally result from concurrent renal efflux disturbances. We herein describe a case of AKI in a patient complicated by renal cell carcinoma (RCC) with renal vein and inferior vena cava (IVC) involvement. A neoplastic thrombus which disrupted the blood flow in the renal vein appeared to play a role in the rapid decline in the renal function. Such a scenario has rarely been mentioned in the previous literature describing the cases of RCC complicated by AKI. Concerns regarding the diagnostic and therapeutic strategies for RCC are also discussed.

Is there a link between the structural impact of thoracic outlet and the development of central venous stenosis

Central venous stenosis (CVS) is a serious complication for chronic hemodialysis (HD) patients. Previous reports of CVS have focused on prior central venous catheterization, because of the higher prevalence and potential for prevention of such an event. However, recent studies have demonstrated that CVS may also develop without a history of central venous catheterization. Although information about the etiological backgrounds regarding the development of CVS without previous central venous catheterization have gradually accumulated, the clinical impact of the chronic compression of the central venous system by the surrounding structures, which may likely determine the central venous susceptibility to CVS, remains poorly understood. This study proposes the hypothesis that the combination of chronic venous compression at the level of thoracic outlet characterized by the natural physique and elevated venous flow induced by the creation of vascular access should be evaluated as a potential factor for the development of CVS, since they may accelerate the development of venous stenosis, presumably through the stimulation of intimal hyperplasia, and thereby the subclavian venous susceptibility to CVS should be determined.

Challenges of Caring for an Advanced Chronic Kidney Disease Patient with Severe Thrombocytopenia

An autogenous arteriovenous fistula has been considered to be the optimal form of vascular access for hemodialysis (HD) in the field of nephrology. Nevertheless, the decision regarding the type of access, whether it be an arteriovenous fistula, an arteriovenous graft, or a central venous catheter, must still be individualized. In the present report, we describe the case of a female patient with advanced chronic kidney disease (CKD) associated with a hemostatic disorder. Despite the exhausted peripheral vasculature, she required recurrent platelet transfusions for severe thrombocytopenia due to aplastic anemia. The goal of care for this patient was to optimize the dialysis treatment without increasing the bleeding risk. Various concerns regarding the therapeutic conundrums encountered in the case are also discussed.