Temporary Hemodialysis Research Articles

Laser sheath for tunneled dialysis catheters extraction

The number of patients with acute renal failure and end-stage renal disease undergoing hemodialysis (HD) has increased during the past years, and the management of vascular access is pivotal. Among tunneled dialysis catheters (TDC), Tesio twin-catheter system (Medcomp, Harleysville, PA, USA) provides good long-term survival with acceptably high blood flow and low complication rates [1, 2]. Unfortunately, catheter infection is still a serious and common complication related to temporary HD vascular access. When catheter infection and/or dysfunction occur, extraction is mandatory [3]. Although the development of a fibro-epithelial sheath is a common occurrence, TDC extraction is usually easily performed by traction or cut down technique [3, 4]. However, when the catheters are tethered or attached to central veins and/or to right atrium, these techniques could lead to their rupture and retention and could increase the risk of vascular or atrial wall avulsion. Laser extraction technique is usually adopted for pacing leads, but it can also be helpful in TDC extraction to avoid the previous mentioned complications. A circumferential Excimer laser beam applied at the tip of a specialized telescopic sheath is passed over the lead. The energy source comes from a xenon chloride laser with an output wave length of 308 nm. It is a cool cutting laser (50 C) with a very limited absorption depth; twothirds of the energy are absorbed within 0.06 mm from the tip of the sheath by proteins and lipids instead of water. These technical characteristics allow the ablation of the fibro-epithelial sheath surrounding TDC without damaging the endothelial wall and the catheter itself [5]. According to these assumptions, our laboratory has decided to adopt this technique to extract tethered TDCs. A woman of 57 years, affected by endstage renal disease, was admitted to our Department for a Tesio twin-catheter system-associated bacteraemia. A transesophageal echocardiographic evaluation showed a thrombus occluding the apex of the right atrial appendage. A valvular involvement was excluded. After 2 months of oral anticoagulation therapy, she underwent TDC extraction performed using an Excimer Laser system emitting energy at the tip of a flexible, fiber-optic 12F-sheath (Spectranetics Inc., Colorado Springs, CO, USA). The procedure was performed under assistant sedation with i.v. midazolam. First, the TDC was isolated. Then, an A. Curnis L. Bontempi M. Cerini F. Vassanelli A. Lipari N. Ashofair C. Pagnoni L. Dei Cas Division of Cardiology, EP Lab, Post Graduate School of Cardiology, Spedali Civili, University of Brescia, Brescia, Italy

Aortic valve calcium load before TAVI: Is it important?

Aortic valve calcium load before TAVI: Is it important?

Clinical Performance and Skill Retention after Simulation‐based Education for Nephrology Fellows

We previously demonstrated that simulation-based education (SBE) improved temporary hemodialysis catheter (THDC) insertion skills by nephrology fellows. SBE, featuring deliberate practice and rigorous achievement standards, was a powerful method to enhance THDC insertion skills in nephrology fellows. However, experts have called for further research to evaluate skill transfer from the simulated environment to actual clinical care and skill retention. This is a prospective observational cohort study of THDC insertion skills. Twelve nephrology fellows from three academic centers in Chicago were evaluated using a skills checklist from July 2008 to June 2009. Simulator-trained fellows were tested after the SBE intervention and expected to meet or exceed a minimum passing score (MPS) set by an expert panel. To assess transfer of skill to clinical care, three simulator-trained fellows were assessed at 6 months on actual patient THDC insertions using the checklist. To assess retention of skill, 11 of 12 simulator-trained fellows were reassessed at 1 year using the checklist and central venous catheter simulator. Outcomes were determined by THDC insertion skill performance. Simulator-trained fellows scored similarly during 6-month THDC insertions on actual patients and immediate posttest (M = 86.2%, SD = 22.3% vs. M = 93.5%, SD = 5.3%, p = 0.32). However, 1 year after SBE, simulated THDC insertion scores were significantly lower than at immediate posttest (M = 73.4%, SD = 22.2% vs. M = 93.5%, SD = 5.3%, p = 0.01). Our results show that nephrology fellows who completed SBE displayed high levels of performance during THDC insertions on actual patients 6 months later. At 1 year, there was statistically significant skills decay. We recommend booster training at 6 months.

N-acetylcysteine for the Prevention of Contrast-induced Nephropathy in the Emergency Department

To evaluate the use of N-acetylcysteine (NAC), a potent antioxidant, to prevent contrast-induced nephropathy (CIN). We prospectively studied 209 patients (106 in the NAC group and 103 in the control group) who received contrast-enhanced computed tomography (CECT) in the emergency department (ED). The NAC group received intravenous NAC (600 mg) before CECT imaging to prevent CIN. Both the NAC and control groups were treated using a standardized hydration strategy, where clinically feasible. The patients' mean age was 79.6±9.8 years. The prevalence of hypertension, diabetes, and chronic kidney disease (CKD) were 63.2%, 27.3%, and 21.5%, respectively. The baseline clinical characteristics were similar between the two groups except for their body weight (p=0.011), amount of contrast material administered (p=0.049) and prevalence of CKD (p=0.002). The incidence of CIN was 7.5% in the NAC group and 14.6% in the control group. The adjusted odds ratio was 0.305 (95% confidence interval: 0.097 to 0.960, p=0.042). All-cause mortality was 7.5% in the NAC group and 12.6% in the control group, which was not significantly different. Temporary hemodialysis was required in 0% of subjects in the NAC group and 1.0% in the control group, which was not a statistically significant difference. A single dose of NAC before CECT imaging can prevent CIN in an ED setting. However, it does not improve the mortality rate or the need for dialysis.

Clinical Results of Endovascular Abdominal Aortic Aneurysm Repair in Patients with Renal Insufficiency without Hemodialysis

Chronic renal insufficiency may be a relative contraindication to endovascular aneurysm repair (EVAR) for the use of contrast enhanced mediums. It is thought that more contrast enhanced media are needed in patients who are not anatomically suitable for EVAR, because of procedural difficulties. We reviewed a 2 year EVAR experience at our institution to determine whether the procedure and use of contrast enhanced mediums has any deleterious effect on renal function in patients with pre-existing chronic renal insufficiency. EVAR was performed in 46 patients with pre-existing chronic renal insufficiency without hemodialysis. Patients were retrospectively assigned to two groups on the basis of their preoperative creatinine clearance levels. Furthermore, patients were assigned to two other groups on the basis of anatomical suitability for EVAR. The absolute change in the serum creatinine (Cr) level was reviewed in the each renal insufficiency group between the preoperative and post-operative time periods. No increase in the serum Cr level was noted, and no patient required temporary or permanent hemodialysis, in any of the groups. EVAR with contrast agents can be accomplished in patients with chronic renal insufficiency without hemodialysis; therefore,elevated Cr levels maynot be a contraindication in EVAR.

Unintended Cannulation of the Subclavian Artery in a 65-Year-Old-Female for Temporary Hemodialysis Vascular Access: Management and Prevention

Ultrasound-guided cannulation of a large-bore catheter into the internal jugular vein was performed to provide temporary hemodialysis vascular access for uremia in a 65-yr-old woman with acute renal failure and sepsis superimposed on chronic renal failure. Despite the absence of any clinical evidence such as bleeding or hematoma during the procedure, a chest x-ray and computed tomographic angiogram of the neck showed that the catheter had inadvertently been inserted into the subclavian artery. Without immediately removing the catheter and applying manual external compression, the arterial misplacement of the hemodialysis catheter was successfully managed by open surgical repair. The present case suggests that attention needs to be paid to preventing iatrogenic arterial cannulation during central vein catheterization with a large-bore catheter and to the management of its potentially devastating complications, since central vein catheterization is frequently performed by nephrologists as a common clinical procedure to provide temporary hemodialysis vascular access.

Eculizumab Treatment of Paroxysmal Nocturnal Hemoglobinuria Relapsing After Bone Marrow Transplant and Subsequent Clonal: Case Report

Abstract 5274 Background:Paroxysmal nocturnal hemoglobinuria (PNH) is a chronic and life-threatening hematopoietic stem cell disorder characterized by deficiency of the GPI-anchored complement inhibitory proteins CD55 and CD59 on blood cells. The resulting uncontrolled complement activation is responsible for chronic hemolysis and can lead to serious clinical morbidities including thromboembolism (TE) and chronic kidney disease (CKD), which have been shown to increase risk of mortality. Patients may also experience debilitating quality-of-life (QoL) issues, including fatigue, shortness of breath, erectile dysfunction, and abdominal pain, attributed to chronic hemolysis and resultant nitric oxide scavenging by free hemoglobin.Although hematopoietic stem cell transplantation (HSCT) remains the only potentially curative option for PNH, the risk for substantial morbidities and mortality still exist. In patients with PNH undergoing HSCT, up to 45% die or develop acute or chronic graft-versus-host disease. Eculizumab, a first-in-class terminal complement inhibitor, is the only approved treatment for patients with PNH. By inhibiting terminal complement activity and chronic hemolysis, eculizumab reduces the incidence of TE, CKD, and transfusion requirements, improves anemia and QoL, and normalizes survival in patients with PNH. Aim:Report the benefits of eculizumab in a patient with PNH who relapsed after HSCT. Case Report:A 27-year-old woman presented in December 1993 with fever, diarrhea, hemoglobinuria, and acute renal failure requiring temporary hemodialysis (Table). She was subsequently diagnosed with PNH. In February 1995, allogeneic HSCT from an HLA-identical sibling donor was performed. In 2003, 8 years after successful engraftment, the patient relapsed and presented with hemoglobinuria, abdominal pain, corticosteroid dependence requiring 20 to 40 mg methylprednisone, and high transfusional requirements. In November 2007, she had a granulocyte clone size of 37.2% as determined by flow cytometry. In June 2009, she started eculizumab therapy which was associated with a rapid reduction in lactate dehydrogenase (LDH) from 4964U/L to 456U/L. She subsequently achieved resolution of asthenia, disabling fatigue, and abdominal pain, as well as transfusion independence and improvement in hemoglobin. In May 2010, she had a granulocyte clone size of 86.1% as determined by both CD55- and CD59-negative cells, and a granulocyte clone size of 98.7% as determined by CD16b-negative cells. Conclusions:The only potential cure for PNH—bone marrow transplantation—is associated with high risks of morbidity and mortality; therefore, for most patients the associated risks preclude this option. In this case study, we show that HSCT may not be curative in all patients and the PNH associated symptoms can arise after BMT. The potential benefits of eculizumab in this patient population should be considered in light of recent data that demonstrated normalized survival in PNH patients receiving long-term eculizumab treatment.TableLaboratory CharacteristicsJanuary 1994March 10, 1995June 19, 2009aAugust 31, 2009Hemoglobin, g/dL5.311.86.289.2White-cell count, per mm≥7,8008,1006,0602,600Neutrophils, %—685338Neutrophils, mL—5,5082,69898Platelet count, per mm≥213,000250,000416,000327,000Lactate dehydrogenase, U/L——4,964456Indirect bilirubin, mg/dL1.1—2.203.82baStarted eculizumab June 23, 2009.bExtravascular hemolysis for C3. Disclosures:Brodsky:Alexion Pharmaceuticals, Inc.: Consultancy, Speakers Bureau. Velez:Alexion Pharmaceuticals, Inc.: Consultancy.

Inadvertent arterial catheterization complicating femoral venous access for haemodialysis

Large-bore catheters for temporary haemodialysis are often placed via the internal jugular or femoral vein, guided by external landmarks or ultrasound techniques. Inadvertent femoral artery catheterization may occur during attempted placement of the dialysis catheter in the femoral vein. This investigation was carried out in Skåne University Hospital, Malmö, Sweden. Between 2008 and 2011, patients referred for consultation by a vascular specialist owing to inadvertent arterial catheterization after attempted placement of a dialysis catheter in the femoral vein were noted in a logbook and patients with iatrogenic arterial injuries undergoing vascular repair at Malmö-Lund Hospitals were identified through the Swedish vascular registry (Swedvasc). The five included patients had a dialysis catheter (11-13.5 Fr) inserted, without ultrasound guidance, into the femoral artery. One patient suffered from circulatory shock. Two cases were managed with external compression, while three cases required surgical repair. Two patients had postoperative wound infection in the groin. Femoral dialysis catheters should be inserted using ultrasound guidance. Large-bore catheters suspected of being in an inadvertent arterial position should be fixed securely before further diagnostic or interventional considerations. A management algorithm for inadvertently placed catheters in the femoral artery is proposed.

Ultrasound use for the placement of haemodialysis catheters

A significant proportion of patients starting dialysis do so with a temporary or tunnelled haemodialysis catheter. Insertion of these catheters can be achieved either by using the anatomical landmarks for the veins into which they are inserted or using ultrasound guidance. It has been suggested that the use of ultrasound guidance reduces the immediate complications of haemodialysis catheter insertions such as pneumothorax or arterial puncture. The aim of the review was to compare the use of real-time 2-dimensional (2-D) Doppler ultrasound venous imaging in the insertion of percutaneous central venous catheters for dialysis versus the traditional "blind" landmark method. We searched the Cochrane Renal Group's Specialised Register, MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL). Reference lists of identified studies and relevant narrative reviews were also screened. Search date: January 2011. All randomised controlled trials (RCTs) and quasi-RCTs evaluating ultrasound guidance in the percutaneous insertion of central venous catheters for dialysis (both cuffed and uncuffed) against the traditional blind landmark method. Two authors assessed risk of bias and extracted data. Statistical analyses were performed using the random effects model and the results expressed as risk ratios (RR) for dichotomous outcomes or mean difference (MD) for continuous data with 95% confidence intervals (CI). We identified seven studies enrolling 767 patients and with 830 catheter insertions. Three of seven studies described the method of random sequence generation, none described allocation concealment, and blinding of participants and personnel was not possible. Real-time ultrasound guidance was found to significantly reduce the risk of catheter placement failure on the first attempt (5 studies, 595 catheters): RR 0.40, 95% CI 0.30 to 0.52), significantly reduce the risk of arterial puncture (6 studies, 535 catheters: RR 0.13, 95% CI 0.04 to 0.37) and haematomas (4 studies, 323 catheters: RR 0.22, 95% CI 0.06 to 0.81) when compared to the landmark method. The time taken for successful cannulation was significantly lower with the use of real-time ultrasound guidance (1 study, 73 catheters: MD -1.40 min, 95% CI -2.17 to -0.63) and there were less attempts/catheter insertion (1 study, 110 catheters: -0.35, 95% CI -0.54 to -0.16). Use of real-time 2-D Doppler ultrasound guidance has significant benefits with respect to the number if catheters successfully inserted on the first attempt, reduction in the risk of arterial puncture and haematomas and the time taken for successful vein puncture.

Tissue plasminogen activator versus heparin for locking dialysis catheters: A systematic review

Background and Objectives:Hemodialysis catheters are commonly used when renal replacement therapy is initiated. These catheters have significant complications. Among “locking” solutions used in an attempt to decrease these complications is recombinant tissue plasminogen activator (rt-PA). This systematic review is to determine the efficacy of rt-PA versus heparin, the standard of care.Materials and Methods:A systematic review of randomized controlled trials studying rt-PA alone or rt-PA plus heparin versus heparin alone as locking agents for hemodialysis catheters, which included patients needed a temporary hemodialysis catheter for hemodialysis. We identified relevant trials through electronic databases and correspondence with experts. Two investigators independently reviewed potentially eligible trials and extracted data.Results:Three trials met the inclusion criteria. One trial reported an improved catheter malfunctioning in patients using rt-PA plus heparin to lock catheters (20.0%) versus heparin alone (34.8%). Another trial reported higher blood flow rate in hemodialysis catheters in patients who received rt-PA (231.6 ± 12.4 mL/min) compared with those who received heparin (206.9 mL/min). The third trial reported formation and weight of clots which were decreased by half in rt-PA group versus heparin group.Conclusions:In the few randomized trials that met our inclusion criteria, the use of rt-PA as a locking solution for hemodialysis catheters seems to be associated with fewer adverse events and catheter malfunctioning as compared with heparin. Our systematic review is limited by the few randomized trials addressing our question and the wide variety of outcome measures. Further prospective randomized trials are needed to confirm this conclusion.

Amanita poisonings resulting in acute, reversible renal failure: new cases, new toxic Amanita mushrooms

Renal failure as a consequence of eating mushrooms has been reported repeatedly after ingestion of webcaps of the Cortinarius orellanus group. But mushrooms of the genus Amanita can also cause renal failure: Amanita smithiana (North America) and Amanita proxima (Mediterranean area). Here, we discuss poisonings caused by other white amanitas. A German and--independently--two Portuguese patients reported the ingestion of completely white mushrooms with ring. Similar to intoxications with A. smithiana or A. proxima, the clinical picture was characterized by nausea and vomiting 10-12 h after ingestion, severe acute renal failure and mild hepatitis. Renal biopsy showed acute interstitial nephritis and tubular necrosis. Two patients were given temporary haemodialysis. All have fully recovered their renal function. Poisonings caused by mushrooms containing the toxin of A. smithiana were suspected. We tested 20 Amanita species for the presence of this toxin. Thin layer chromatography was applied to detect A. smithiana nephrotoxin in herbarium specimens using authentic material of A. smithiana as reference. A. smithiana toxin could be detected in Amanita boudieri, Amanita gracilior and in Amanita echinocephala. A. boudieri was collected by the Portuguese patients. A. echinocephala is the only nephrotoxic Amanita growing North of the Alps and is suspected to be the cause of renal failure in the German patient. No A. smithiana toxin was detectable in the nephrotoxic A. proxima. A. boudieri, A. gracilior and A. echinocephala are nephrotoxic. These intoxications are clinically similar to that of A. smithiana, with acute reversible renal failure and mild hepatitis but are different in their clinical picture from Orellanus syndrome characterized by a delayed onset of severe and often irreversible renal failure.

A propensity score–matched comparison of deep versus mild hypothermia during thoracoabdominal aortic surgery

By using deep hypothermic circulatory arrest and non-deep hypothermic circulatory arrest approaches, we examined the impact of distal ischemia time and temperature on intra-abdominal reversible adverse outcomes and permanent adverse outcomes during descending thoracic aortic and thoracoabdominal aortic aneurysm operations. A retrospective review of all patients who underwent descending thoracic aortic and thoracoabdominal aortic aneurysm repair between January 2002 and December 2008 was undertaken, including relevant preoperative, intraoperative, and postoperative data, and followed by a propensity score-matched analysis. Of the total of 262 patients, 240 had data complete enough to permit analysis, and 90 were suitable for the propensity-matched study. Reversible adverse outcomes included renal failure, liver failure, and temporary hemodialysis. Permanent adverse outcomes included paraplegia, permanent hemodialysis, and 30-day mortality. Thirty-day mortality was 7.1% (17/240). Overall, reversible adverse outcomes developed in 40.8% of patients and permanent adverse outcomes developed in 10% of patients. The propensity score analysis identified statistically significant decreased odds of developing reversible adverse outcomes in patients undergoing deep hypothermic circulatory arrest (odds ratio, 0.32; confidence interval, 0.12-0.85). Specifically, significantly lower rates of acute renal failure (22% vs 46.4%, P=.03) and liver failure (17.8% vs 34.3%, P=.04) were observed in the deep hypothermic circulatory arrest group compared with the non-deep hypothermic circulatory arrest group. In addition, there were decreased odds of reversible adverse outcomes (odds ratio, 0.22; confidence interval, 0.06-0.79) developing in patients with a stage II elephant trunk procedure. During descending thoracic aortic and thoracoabdominal aortic aneurysm repairs, the use of deep hypothermic circulatory arrest results in improved postoperative adverse outcome rates compared with non-deep hypothermic circulatory arrest techniques. The development of reversible adverse outcomes is strongly associated with the development of permanent adverse outcomes.

Partial nephrectomy in two patients with known T3a tumours involving the renal vein

Study Type--Therapy (case series). Level of Evidence 4. What's known on the subject? And what does the study add? Although nephron-sparing surgery (NSS) has became accepted therapy for T1 tumours, radical nephrectony is considered the best therapy for T3a tumours involving the renal vein. NSS can be considered in T3a or greater tumours if imperative indications exist, such as bilateral disease or solitary kidney. However, there is little published data on the characteristics of these patients, the impact of surgery on their renal function, and long-term oncologic outcomes. This study profiles single-institution experience with nephron-sparing surgery for known T3a tumours involving the renal vein, including patient characteristics, tumour characteristics, preoperative and follow-up imaging, preoperative and follow-up estimated glomerular filtration rate, length of temporary postoperative haemodialysis, and oncologic outcome. Additionally, we compare this to other published data on nephron-sparing surgery for similar tumors. • To present two patients with T3a tumours involving the renal vein who underwent nephron-sparing surgery (NSS) for imperative reasons. • Retrospective chart review of patients who underwent NSS for renal cell carcinoma (RCC) with known renal vein tumour thrombus (RVTT). • Both patients underwent open partial nephrectomy and renal vein thrombectomy of a solitary kidney. • Primary outcomes of the study include radiographic evidence of recurrence, haemodialysis requirement and estimated glomerular filtration rate (eGFR) before and after surgery. • Patient 1 is 24 months from NSS and has no evidence of recurrence based on CT scan. His final pathology revealed a 9-cm, T3a, clear cell, Fuhrman grade II carcinoma. He spent 42 days on haemodialysis and is now off all dialysis. His preoperative and most recent eGFR are 48 and 23 mL/min/1.73 m(2) based on the Modification of Diet in Renal Disease (MDRD) equation and 69.4 and 29.8 mL/min by the Cockcroft-Gault equation. • Patient 2 is 9 months from NSS and has no evidence of recurrence based on CT scan. Her final pathology revealed a 6-cm, T3a, clear cell, Fuhrman grade II-III carcinoma. She spent 30 days on haemodialysis and is now off all dialysis. Her preoperative and most recent eGFR are 58 and 30 mL/min/1.73 m(2) based on the MDRD equation and 62.2 and 32.8 mL/min by the Cockcroft-Gault equation. • Based on our review, preservation of renal function and favourable oncological outcome can be accomplished with NSS in patients with known stage T3a RCC with RVTT and should be considered in carefully selected patients.

Low-Dose Heparin Retention in Temporary Hemodialysis Double-Lumen Catheter Does Not Increase Catheter Occlusion and Might Reduce Risk of Bleeding

Background: The objective of this study was to assess the impact of heparin concentration retained in temporary double-lumen catheters on bleeding risk. Methods: Activated partial thromboplastin time (aPTT) was measured in patients hemodialyzed via double-lumen catheters. Heparin solutions of 5,000 U/ml (group 1, n = 95) and 1,000 U/ml (group 2, n = 89) were randomly retained in catheters after placement and each hemodialysis (HD) session. Blood transfusion, bleeding episodes, and changes of hematocrit were recorded. Results: The aPTT at the beginning of HD or 10 min after heparin lock was significantly prolonged, which was more prominent in the 5,000 U/ml group, whereas the aPTT declined to baseline values at the end of HD or before the next dialysis session in both groups. Infection and occlusion rates were similar in both groups. More patients suffered from major bleeding and prominent decline of hematocrit in the 5,000 U/ml group. Conclusions: Low-dose heparin (1,000 U/ml) retention in double-lumen catheters for temporary HD maintains comparable catheter patency and might reduce the bleeding risk.

Fungal peritonitis in patients undergoing continuous ambulatory peritoneal dialysis in Qatar

This study was conducted at Hamad General Hospital to determine the incidence of fungal peritonitis and to describe its clinical and microbiological findings in patients undergoing continuous ambulatory peritoneal dialysis in Qatar. The medical records of these patients between 1 January 2005 and 31 December 2008 were retrospectively reviewed and the collected data were analysed. During the study period, 141 episodes of peritonitis were observed among 294 patients. In 14 of these episodes (9.9%), fungal peritonitis was reported in 14 patients with a rate of 0.05 episodes per patient year, while the bacterial peritonitis rate was 0.63 per patient year. Thirteen (93%) patients had one or more previous episodes of bacterial peritonitis that was treated with multiple broad-spectrum antibiotics, 11 (85%) had received broad-spectrum antibiotics within the preceding month, 12 (92%) within three months, and 8 (62%) within six months. Candida species were the only fungal species isolated from the dialysate with predominance of non-albicans Candida species (especially Candida parapsilosis). Therapeutic approach was immediate catheter removal, followed by systemic antifungal therapy and temporary haemodialysis. Nine patients (64.3%) were continued on haemodialysis, whereas five patients (35.7%) died. Prior antibiotic use was an important risk factor predisposing patients to the development of fungal peritonitis. Early detection of fungal peritonitis would lead to early institution of appropriate therapy and prevention of complications.

アンジオテンシンII受容体拮抗薬(losartan)が有効と考えられた強皮症腎クリーゼの1例

A 67-year-old man with a one-and-a half-year history of Raynaud's phenomenon was admitted to our hospital for progressive dyspnea occurring over the previous two weeks. Physical examination revealed a blood pressure of 200/124 mmHg, and slightly tight and smooth skin of the fingers, hands and forearms. Laboratory evaluation included serum creatinine of 5.42 mg/dl, plasma renin activity > 20 ng/ml/hr, and antinuclear antibody with a titer of 1 : 1,280. Renal biopsy was performed and the histopathological findings showed that some glomeruli exhibited ischemic retraction with wrinkling of the basement membranes, and that one arteriole exhibited significant intimal hyperplasia with luminal stenosis. These findings were compatible with scleroderma renal crisis (SRC). On the 5th day, serum creatinine had risen to 9.16 mg/dl, and he required temporary hemodialysis therapy. After the administration of captopril was started, his blood pressure fell to 160/86 mmHg and serum creatinine was reduced to 5.12 mg/dl. On the 9th day, he exhibited skin eruptions, and captopril was discontinued accordingly and temocapril started. Because of continued eruptions, temocapril was replaced by losartan. His blood pressure was controlled easily and his serum creatinine level reduced steadily. One year after the start of losartan, serum creatinine was 2.25 mg/dl and blood pressure was 130/82 mmHg. SRC is a life-threatening manifestation of systemic sclerosis. In the late 1970s, angiotensin converting enzyme (ACE) inhibitor was introduced and has dramatically improved the outcome in SRC patients. As ACE inhibitors act mainly on hyperreninemic renal vasoconstrictive hypertension in SRC, we would expect losartan, a selective antagonist of angiotensin receptor subtype 1, to be interchangeable with ACE inhibitors in SRC. In 1997, Caskey and colleagues reported the failure of losartan to control hypertension in a patient of SRC, and the reason has remained unclear. We report here, a case of SRC whose blood pressure was controlled successfully and his renal failure reversed by the administration of losartan.

Two cases of nephrotic syndrome (NS)-induced acute kidney injury (AKI) associated with renal hypouricemia

Renal hypouricemia is a clinical disorder attributed to an increased renal urate excretion rate and is well known to involve a high risk of urolithiasis and exercise-induced acute kidney injury (AKI). This report concerns two interesting cases of nephrotic syndrome (NS)-induced AKI associated with renal hypouricemia. A 64-year-old female (Case 1) and a 37-year-old male (Case 2) were hospitalized because of AKI (serum creatinine: 2.07 mg/dl and 3.3 mg/dl, respectively), oliguria and NS. They were treated with prednisolone and temporary hemodialysis. Renal function improved, but hypouricemia persisted during hospitalization. Histological findings in both cases led to a diagnosis of minimal change nephrotic syndrome and identification of the diuretic phase of tubulointerstitial damage because of findings such as acute tubular necrosis. Furthermore, distal tubules of Case 2 showed an amorphous mass, possibly a uric acid crystal. Analysis of the two cases with the URAT1 gene, encoded by SLC22A12, found a homozygous mutation in exon 4 (W258stop) of each one. Our cases show that patients with renal hypouricemia may be susceptible to AKI without involvement of exercise if they possess some facilitators. Renal hypouricemic patients should therefore be carefully examined for all complications from renal hypouricemia because of high risk of AKI.

A dangerous entanglement

Entrapment of guidewires by inferior vena cava filters can occur during the blind insertion of a jugular or a subclavian central venous catheter. Recently, few case reports have been published in the radiology literature. In addition, others have described endovascular techniques aimed at removing entrapped guidewires, avoiding the possibility of vena cava rupture. Given that a temporary hemodialysis venous catheter is frequently used as a first access, the possibility of entrapping the dialysis catheter guidewire should not be neglected.

The D&T Report

The D&T Report

A case of progressive thrombotic microangiopathy after ABO‐incompatible renal transplantation

A 21-yr-old man of blood type O receiving hemodialysis for IgA nephropathy underwent living-related ABO-incompatible (ABOI) renal transplantation from his mother, whose blood type is A. He was negative for flow cross-match, anti-human leukocyte antigen (HLA) antibody, and anti-MICA antibody. Pre-treatment anti-A IgG titer was 1:256. Desensitization consisted of tacrolimus, mycophenolate mofetil, methylprednisolone, rituximab, and plasmapheresis. He developed acute antibody rejection at day 2 post-transplant, which was successfully treated. After renal artery reconstruction surgery at day 91 for renovascular hypertension caused by renal artery stricture, the patient suffered from acute prostatitis, which subsequently induced type III acute antibody-mediated rejection. Even after recovery from the rejection after temporary hemodialysis, graft function progressively deteriorated and consecutive allograft biopsy showed progressive thrombotic microangiopathy (TMA) without any evidence of donor-specific antibody other than anti-A antibody. The tacrolimus dose was kept low for fear of tacrolimus-induced TMA. Despite these efforts, the patient resumed hemodialysis six months' post-transplant.