No abstract

The guideline committee of Japanese Society for Dialysis Therapy (JSDT), chaired by Dr Ohira, has published an original Japanese guideline, 'Guidelines for Vascular Access Construction and Repair for Chronic Hemodialysis'. The guideline was created mainly because of the existence of numerous factors characteristic of Japanese hemodialysis therapy, which are described in this report, and because we recognized the necessity for standardization in vascular access-related surgeries. This guideline consists of 10 chapters, each of which includes guidelines, explanations or comments and references. The first chapter discusses informed consent of vascular access (VA)-related surgeries, which often resulted in trouble between dialysis staff and patients. The second chapter describes the fundamentals of VA construction and timing of the introduction of hemodialysis with emphasis on the avoidance of catheter indwelling if at all possible. In the third chapter, arteriovenous fistula (AVF) construction and management are discussed from the viewpoint of the most preferable type of VA. The fourth chapter deals with arteriovenous grafts (AVG) which has recently increased in clinical applications. The factors which improve the AVG patency rate are discussed and postoperative management methods are emphasized to avoid possible complications. The fifth chapter deals with short and long-term vascular catheters. It is emphasized that these methods are definitely effective but, at the same time, are apt to be associated with several serious complications and might result in vascular damage. In the sixth chapter, superficialization of an artery is explained. This was originally for emergency use or backup but has been used permanently in 2-3% of Japanese hemodialysis patients. In the seventh chapter, methods for the use of VA are described and the buttonhole method is referred to as one of the options for patients who complain of intense pain at every cannulation. In the eighth chapter, the importance of continuous monitoring is stressed for maintaining appropriate function of VA. As a rule, the internal shunt type VA (AVF, AVG) places a burden on cardiac function. Thus, in the ninth chapter, it is stressed that VA construction, maintenance and repair should always be carried out with consideration of cardiac function which is not constant but variable. The 10th chapter forms one of the cores of this guideline and deals with repair and timing of VA. It is shown how to select a surgical or interventional repair method. In the final 11th chapter, VA types and resultant morbidity and mortality of hemodialysis patients are reviewed.

SUMMARYPirfenidone has been shown to modify some cytokine regulatory actions and inhibit fibroblast biochemical reactions resulting in inhibition of proliferation and collagen matrix synthesis by fibroblast. We have investigated the effect of pirfenidone on the expression of cell adhesion molecules. The synovial fibroblasts were treated with IL-1a in the presence or absence of pirfenidone (range 0-1000 mM), and assayed for the expression of adhesion molecules such as ICAM-1 and endothelial-leucocyte adhesion molecule-1 (E-selectin) by cell ELISA. Pirfenidone significantly down-regulated the expression of ICAM-1 on cultured synovial fibroblasts in a dose-dependent manner. In contrast, expression of Eselectin was not affected. Furthermore, we examined whether pirfenidone affects the cellular binding between cultured lymphocytes and IL-1a-stimulated synovial fibroblasts by in vitro binding assay and found their mutual binding was significantly suppressed in a dose-dependent manner by pirfenidone. It is speculated that down-regulation of ICAM-1 might be one of the novel mechanisms of action of pirfenidone. These data indicate a novel mechanism of action for pirfenidone to reduce the activation of synovial fibroblasts.

Object: To study the effects of the intravenous administration of methylcobalamin, an analogue of vitamin B12, for uremic or uremic-diabetic polyneuropathy in patients whoare receiving maintenance hemodialysis. An ultra-high dose of vitamin B12 has been reported to promote peripheral nerve regeneration in experimental neuropathy. Methods: Nine patients received a 500|ig methylcobalamin injection 3 times a week for 6 months. The effects were evaluated using neuropathic pain grading and a nerve conduction study. Results: Serum concentrations of vitamin B12 were ultra-high during treatment due to the lack of urinary excretion. After 6 months of treatment, the patients' pain or paresthesia had lessened, and the ulnar motor and median sensory nerve conduction velocities showed significant improvement. There were no side effects. Conclusion: Intravenous methycobalamin treatment is a safe and potentially beneficial therapy for neuropathy in chronic hemodialysis patients. (Internal Medicine 38: 472-475, 1999)

Dialysis-related amyloidosis (DRA) is characterized by the presence of beta 2-microglobulin (beta 2-m) in the plasma. In order to eliminate beta 2-m from the circulating blood, the beta 2-m selective adsorbent for direct hemoperfusion (DHP) was developed. A DHP column (BM-01), containing 350 ml of the adsorbent, was subjected to clinical trials. The column was connected with a PAN (AN69) membrane dialyzer in series and used 3 times a week for 1 week (11 patients), 4 weeks (5 patients), 6 months (1 patient) and 12 months (2 patients). The percent reduction (%) of beta 2-m was for 16 patients (for 1 or 4 weeks), more than 65, and for 3 patients (for more than 6 months), 76.5 +/- 4.9, 73.5 +/- 5.7, 72.2 +/- 6.2. At the end of each session, beta 2-m plasma levels were found to be below 10 mg/L, with 3.4 mg/L being the lowest. The total amounts of beta 2-m removed were 172.5 +/- 22.3, 257.0 +/- 75.6, 157.6 +/- 32.2 and 429.8 mg/session at max. Two out of these three patients had a favorable effect on joint symptoms and ocular fundus. It can be concluded that this selective adsorption therapy may delay the progression of DRA, and is worth considering for wide application.