We investigated the long‒term outcomes of 19 cases in which the GIT（graft inclusion technique）, a technique for reducing the flow volume passing through high‒flow vascular access points, was performed. In the GIT, a PTFE graft of 4 mm in diameter is sewn to an expanded anastomotic site, and a length of about 4 cm is inserted into the target blood vessel to reduce its flow volume. In the examined cases, the median blood flow rate was 2,200 mL/min preoperatively, 880 mL/min immediately after the operation, and 940 mL/min in the remote period. The flow volume control rate was 39.8％ immediately after the operation and 39.6％ in the remote period, and the median operation time was 90.0 minutes. During the follow‒up period（median duration：3.0 years, maximum duration：6.9 years）, there were no direct cases of graft infection and no recurrence of high flow volume. The primary patency rate was 66.2％ at 1 year, 42.8％ at 3 years, and 28.5％ at 5 years, and the secondary patency rate was 100％ at 1 year, 87.1％ at 3 years, and 67.7％ at 5 years. One advantage of this method is that it is simple; i.e., a PTFE graft is inserted 3 to 4 cm into the target site through exfoliation alone on the vein side, and no adjustment of the intraoperative flow rate is required. This surgical procedure can be performed at any anastomotic site, including the elbow, and access can be preserved without interfering with the existing puncture site. The contraction of anastomotic regions affected by aneurysms is simultaneously induced. The long‒term flow‒reducing and patency‒inducing effects of the GIT were confirmed.
［Objectives］In the standard anastomosis method（functional side‒to‒end anastomosis） for the creation of arteriovenous fistulas（AVF） from autologous blood vessels, bending of the vein wall at the center of the anastomosis is sometimes experienced. We have devised a method to prevent such bending of the vein wall. We report on its usefulness.［ Method］The key points of this method are（1） to obliquely incise the vein wall and（2） to create an anastomosis using the upper and lower surfaces of the relevant artery and vein, respectively. The subjects were limited to cases in which an AVF was created using the radial artery and cephalic vein for the first time. We compared 52 cases involving the conventional method with 89 cases involving the venous wall oblique incision method. ［Results］There were no significant differences in patient background factors between the two groups. According to the Kaplan‒Meier method, the 1‒, 3‒, and 5‒year AVF primary patency rates in the conventional method and venous wall oblique incision method groups were 73.8％ vs. 76.8％, 47.5％ vs. 68.4％, and 38.1％ vs. 68.4％, respectively. The patency rates of the venous wall oblique incision group were significantly higher than those of the conventional method group（Log‒rank test, p＝0.0416）.［ Discussion and conclusion］A recent study based on computer simulations suggested that a change in hemodynamics is associated with the onset of shunt vessel stenosis after AVF anastomosis creation. Specifically, an increase in shunt blood flow disturbances might cause thickening of the inner surface of the shunt vessel, thrombus formation, and/or stenosis or obstruction of the shunt vessel. It is speculated that the reduction in venous wall bending at AVF anastomoses brought about by the venous wall oblique incision method might reduce blood flow disturbances in shunt vessels and improve AVF patency.
Single needle‒hemodialysis（SN‒HD） with a puncture needle is sometimes performed in cases in which it is difficult to puncture the blood return side and for self‒puncturing during home dialysis, but it is also indicated for cases in which high dialysis efficiency is not required. We hypothesized that there might be some scenarios in which performing SN‒HD using a single‒lumen catheter（SLC） would also be effective. However, as it was unclear how much dialysis efficiency decreases when SN‒HD is performed using a SLC, we studied the optimal conditions for maximizing dialysis efficiency so that this technique could be used in a wide range of patients. The blood flow volume for the study was fixed at 300 mL/min, and 11 directions in which the pressure could be switched were set. The amount of movement and recirculation rate of simulated blood were measured for ten minutes, after which the actual processed amount was calculated. As a result, the actual processing rate at the default pressure for switching（200/100 mmHg） was found to be approximately 104 mL/min, while the highest processing rate seen was 130 mL/min at a pressure of 300/150 mmHg. This study revealed the optimal conditions for performing SN‒HD using a SLC, which could result in greater dialysis efficiency than is produced by the default conditions.
Evocalcet is a calcimimetic agent with a strong lowering effect on parathyroid hormone （PTH） levels. It is safer to take than cinacalcet hydrochloride, as it is less likely to cause upper gastrointestinal tract symptoms or interact with other drugs. According to the package insert for evocalcet, the initial dose should be 1 mg, regardless of previous cinacalcet doses. In this study, 92 patients that were undergoing hemodialysis at our facility were divided into three groups： the low‒dose （n＝33）, medium‒dose （n＝46）, and high‒dose （n＝13） groups, who were treated with cinacalcet doses of ＜25 mg, ≧25 mg and ＜50 mg, and ≧50 mg, respectively. After they were switched to 1 mg evocalcet, their progress was monitored, and their serum PTH, corrected calcium, and phosphorus levels were measured for up to 12 months. The equivalent evocalcet doses for cinacalcet doses of 25‒100 mg were found to be 0.2 mg for 12.5 mg, 1.4 mg for 25 mg, 4.0 mg for 50 mg, 6.9 mg for 75 mg, and 10.3 mg for 100 mg. These findings suggest that when switching patients to evocalcet it is necessary to set the initial dosage based on the equivalent dose or increase the dose quickly, as needed.
Coronavirus disease 2019 （COVID‒19） has become a pandemic, and the number of patients receiving renal replacement therapy （RRT） due to acute kidney injuries （AKI） caused by COVID‒19 has increased. We experienced several cases in which COVID‒19 patients underwent RRT at our institution, and managed to prevent infections from contaminated artificial kidney dialysis machines. When a dialysis machine was used for a COVID‒19 patient, it was not used again for ≥10 days because it was not known how long it takes for the virus to become unviable. Therefore, we were concerned that a shortage of machines for RRT might occur if the number of AKI patients with COVID‒19 continued to increase. To solve this issue, we tested the surfaces, internal fans, and filters of a dialysis machine for severe acute respiratory syndrome coronavirus 2 （SARS‒CoV‒2） using the reverse transcription polymerase chain reaction after a COVID‒19 patient underwent RRT. The results obtained for nine locations, including sites outside and inside of the machine, were all negative. Shortening the time that dialysis machines are kept out of use for after they have been used for COVID‒19 patients requires careful consideration. Further investigations of this issue, involving different environments, are needed.
A 56‒year‒old male with diabetic nephropathy was started on continuous ambulatory peritoneal dialysis （CAPD） in May 2018. Approximately 2 months later, he was admitted to our hospital because of weariness. A chest X‒ray showed right‒sided hydrothorax. The CAPD was interrupted, and the hydrothorax disappeared. However, the hydrothorax recurred when the CAPD was restarted. Thoracentesis was performed, and transudative pleural effusion was noted. Thus, we diagnosed the patient with pleuroperitoneal communication. Video‒assisted thoracoscopic surgery was carried out. After dialysis solution containing indigo carmine dye was passed through a CAPD catheter, it was shown to flow through a fistula near the right central tendon of the diaphragm. The fistula was directly closed with an automatic anastomotic device. CAPD was restarted 14 days after the surgery. A few days later, the right‒sided hydrothorax recurred. We suspected recurrent pleuroperitoneal communication. Thoracentesis was performed by passing dialysis solution containing indigo carmine dye through a CAPD catheter. The pleural effusion was not colored with indigo carmine dye and appeared hemorrhagic and exudative. These findings excluded tuberculous and cancerous pleural effusion. We diagnosed the patient with uremic pleuritis and initiated hemodialysis. No recurrence of the hydrothorax has been detected since the treatment.
We report a case of acute infectious purpura fulminans（AIPF）due to E. coli in a hemodialysis patient. An 81‒year‒old female, who has been receiving hemodialysis for 4 years, was admitted to our hospital to undergo treatment for dyspnea and shock. Her laboratory data suggested pancytopenia, disseminated intravascular coagulation, and septic shock. A blood culture was positive for E. coli. Five days after admission, purpura with grayish‒white spots spread from the patient’s extremities to her groin and back. The skin lesions became necrotic. We diagnosed her with acute infectious purpura fulminans due to E. coli. Intensive treatment, involving antibiotics, fresh frozen plasma, heparin, skin lesion debridement, and hemodialysis, was performed. The patient died 15 days after admission. AIPF is rare, especially in hemodialysis patients. In adults, the most common form is meningococcal sepsis, followed by pneumococcal sepsis. There have not been any reports about E. coli‒induced AIPF in hemodialysis patients. Physicians should be aware that E. coli can cause purpura fulminans and start appropriate treatment quickly in cases of E. coli‒induced purpura fulminans.
A 71‒year‒old male had started receiving maintenance hemodialysis 8 years ago. He had been diagnosed with rheumatoid arthritis at another hospital, based on his serological and imaging findings, 5 years ago. He was initially treated with disease‒modifying antirheumatic drugs, including salazosulfapyridine（SASP）and 2 mg/day of prednisolone（PSL）；however, he stopped taking PSL after developing a stomachache. The SASP did not affect his disease activity. Four years ago, he began taking etanercept, a biologic drug that is often used to treat rheumatoid arthritis. However, it was ineffective so we discontinued it. Tocilizumab（TCZ）, another biologic drug, was started 3 years and 6 months ago, and the patient’s joint symptoms and blood test results improved. However, after taking TCZ for 1 year and 2 months, he developed allergic dermatitis, and the treatment was halted. We initiated treatment with golimumab and abatacept（biologic drugs）. The allergic dermatitis symptoms resolved； however, the joint symptoms recurred. Thus, these drugs were discontinued. We then administered sarilumab （SAR）, another biologic drug, and found that it improved the patient’s joint symptoms and blood test results. Methotrexate is contraindicated for hemodialysis patients with rheumatoid arthritis； therefore, PSL and biological agents are often used to treat refractory rheumatoid arthritis patients who are on hemodialysis. Unlike other biologic drugs, SAR was effective in the reported patient, who was on hemodialysis and had intractable rheumatoid arthritis.