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Yoshindo Kawaguchi

Publications and source records attributed to Yoshindo Kawaguchi.

30 records · Page 2Linked to original sources
PubMed2002

Clinical effects of L-threo-3,4-dihydroxyphenylserine on orthostatic hypotension in hemodialysis patients.

Orthostatic hypotension is one of the major factors interfering with everyday activities in hemodialysis patients, but there has been no effective agent for treating it. In order to clarify the clinical effects of L-threo-3,4-dihydroxyphenylserine (L-DOPS) on orthostatic hypotension of hemodialysis patients, we conducted a randomized, double-blind comparative trial. 149 regular hemodialysis patients with orthostatic hypotension were randomly allocated to three groups and L-DOPS at doses of 400 mg, 200 mg or placebo was orally administrated to each group 30 min before starting every hemodialysis for 4 weeks. Changes of blood pressure (BP) in orthostatic hypotension immediately after completion of hemodialysis and symptoms related to orthostatic hypotension were compared between the three groups. In the 400-mg group, systolic and diastolic BP after standing increased significantly and the drop of mean BP after standing was also reduced compared with pretreatment levels. No such changes were observed in the placebo group. Fatiguability, malaise/weakness, dizziness and light-headed feeling, the interdialytic symptoms commonly observed in hemodialysis patients who developed orthostatic hypotension, were improved to a significant extent in the L-DOPS group compared with the placebo group. In particular, the improvement was more remarkable for the L-DOPS 400-mg group than the placebo group in patients with diabetic nephropathy, lower systolic BP after standing, and the long duration type of orthostatic hypotension. The incidence of adverse events was comparable between the three groups, and all recovered after discontinuation of L-DOPS or concomitantly administered drugs, or without any treatment. These findings indicate that L-DOPS taken before hemodialysis prevents orthostatic hypotension in patients undergoing hemodialysis, and is also effective for the interdialytic symptoms related to orthostatic hypotension.

Aged↗
PubMed2002

The negative Ca(2+) balance is involved in the stimulation of PTH secretion.

The low calcium (Ca(2+)) dialysate have been developed to diminish the risk of hypercalcemia with the administration of active vitamin D and Ca(2+) carbonate as phosphate binder. Today, increasing numbers of hemodialysis (HD) patients have been on the low Ca(2+) dialysate (Ca(2+) = 2.5 mEq/l). However, the clinical consequences of a negative calcium net-balance which may be induced by the use of low Ca dialysate are not well evaluated. In the present study, we explored the effects of low Ca(2+) dialysate on the calcium balance and the PTH secretion. Eighty one chronic HD patients (male/female: 47/34; mean age: 60.2 +/- 1.5 years; mean HD periods: 11.1 +/- 0.8 years) who had been dialyzed with 3.0 mEq/l Ca(2+) dialysate were studied. All patients were transferred to the low Ca dialysate, which actually brought about a negative net-balance in Ca (mean: -94.5 mg) and an increase in serum intact PTH levels (mean: +23.7%: p = 0.03) during a single HD session. However, no changes in serum ionized Ca(2+) were found in spite of negative Ca(2+) balance. One month after change to the low Ca(2+) dialysate (total 12 sessions in each case), serum intact PTH levels increased significantly (186.7 +/- 19.5 vs. 216.2 +/- 21.9 pg/ml: p = 0.01) in spite of the fact that no changes were found in serum ionized Ca(2+), Pi and Mg. This result indicates that the negative Ca(2+) balance during low-Ca(2+) hemodialysis-stimulated PTH secretion, which offset the decrease of serum Ca(2+); a trade-off phenomenon between negative Ca balance and PTH. This suggests that low Ca(2+) dialysate may exaggerate the progression of secondary hyperparathyroidism.

Calcium↗
PubMed2002

[Long-standing high-transport membrane as a risk factor for EPS development after PD withdrawal: an analysis based on changes in peritoneal function during and after CAPD withdrawal].

The pathophysiology of encapsulating peritoneal sclerosis (EPS) that develops after withdrawal from long-standing dependence on CAPD remains unclear. The aim of this study was to clarify the risk factors for EPS as expressed in the peritoneal function. Fourteen patients who had shifted to standard hemodialysis after long-term CAPD (average, 105 months) were studied: 3 developed EPS after PD withdrawal while 11 did not. Analysis of the data obtained from the peritoneal equilibration test (PET) revealed that: (1) the dialysate/plasma creatinine ratio (D/Pcr) was significantly higher in the EPS group than in the non-EPS group during the course of PD as well as after PD withdrawal; and (2) eight patients, including the 3 with EPS, were classified as being in a high-transport membrane state (HTS) at PD withdrawal. The duration of HTS during PD was longer in those patients with EPS. During the periods after PD withdrawal, none of these EPS patients recovered from HTS, whereas 4 of the 5 non-EPS patients did. These data suggest that long-standing HTS during the course of PD as well as post-withdrawal, may be risk factors for EPS development. For this reason, it is indicated that PET has clinical relevance in examining sequential changes in peritoneal function and in detecting those patients at risk of EPS.

Adult↗
PubMed2002

Encapsulating peritoneal sclerosis in patients undergoing continuous ambulatory peritoneal dialysis in Japan.

Encapsulating peritoneal sclerosis (EPS) is recognized as a serious complication in patients on continuous ambulatory peritoneal dialysis (CAPD). We retrospectively studied the management of CAPD patients who developed EPS in 157 CAPD centers in Japan. Among 11,549 patients undergoing CAPD between 1980 and 2000 in 157 centers, 256 patients developed EPS. The EPS developed between 10 and 168 months (average: 99.6 months) after the start of CAPD. Of the 256 patients who developed EPS, 104 (40.6%) were using high glucose CAPD solution; however, 135 (52.7%) were not. Only 27 patients who developed EPS (10.5%) were using beta-blockers; many other patients were not. A history of peritonitis was seen in 232 patients (90.6%), but not in 11 other patients (4.3%). The average frequency of peritonitis before development of EPS was 3.3 times higher in patients who developed EPS than in those who did not. Various therapeutic approaches were tried with 101 of the patients who developed EPS. Steroid therapy, including pulse therapy, was used to treat 84 patients (83.2%), and total parenteral nutrition was used to treat 80 patients (79.2%). Total intestinal enterolysis was performed in 31 patients (30.7%). Immunosuppressive agents were used in only 8 patients (7.9%). After 2 years, 100 patients (39.1%) were known to have died; 143 (55.9%) patients were known to still be alive. The most important problem for the living EPS patients was their mental condition, especially depressive state. However, only 22 of 133 patients (16.5%) were able to consult with a counselor in the hospital. A mental health support system should be provided to EPS patients in Japan.

Humans↗
PubMed2002

High-transport membrane is a risk factor for encapsulating peritoneal sclerosis developing after long-term continuous ambulatory peritoneal dialysis treatment.

Increased peritoneal function has been suggested to be a risk factor for developing encapsulating peritoneal sclerosis (EPS); however, clinical evidence is scarce. The present study aimed to clarify the specific character of peritoneal function in patients who developed EPS after withdrawal from peritoneal dialysis (PD). We studied 12 patients who developed EPS after PD withdrawal [(EPS group) mean PD duration: 109 months; mean period of EPS development: 7.0 months after withdrawal] and 128 patients who did not develop EPS (non EPS group). All 140 patients were withdrawn from continuous ambulatory peritoneal dialysis (CAPD) and were observed for the following 24 months. Based on the records of the annual peritoneal equilibration tests (PETs), we analyzed (1) the patients' dialysate-to-plasma (D/P) creatinine at various durations on PD, and (2) the accumulative appearance incidence of high-transport (HT) state of peritoneal membrane. The mean D/P creatinine in EPS group was significantly higher than that in the non EPS group in the course of PD from the 6th to the 10th year. The accumulative incidence of HT was significantly higher in the EPS group than in the non EPS group, indicating early development of HT membrane in EPS group. Early development of increased D/P creatinine, classified as HT state, was observed during certain periods on PD in patients who developed EPS after PD withdrawal. That finding may indicate that HT state of peritoneal membrane is an early marker for EPS, and that the PET is useful to detect patients at high risk of EPS.

Adult↗
PubMed2002

Fifteen cases of encapsulating peritoneal sclerosis related to peritoneal dialysis: a single-center experience in Japan.

To evaluate the incidence and characteristics of encapsulating peritoneal sclerosis (EPS), we analyzed 111 patients who had been transferred to hemodialysis and had been periodically monitored using the peritoneal equilibration test. Encapsulating peritoneal sclerosis was diagnosed in 11 patients. All patients had high-transport peritoneum, and 10 patients had been treated with continuous ambulatory peritoneal dialysis (CAPD) for more than 72 months. Incidence of EPS increased according to prolongation of CAPD. To evaluate outcome, we analyzed 15 cases of EPS. All patients were treated with total parenteral nutrition (TPN). Five patients improved with TPN alone. However, the remaining 10 patients showed deterioration. Of those 10, 4 patients died. They had not been treated with corticosteroids (CSs). The remaining 6 patients were treated with CSs, but they did not improve. Those cases required surgical treatment. The postoperative course in 4 patients was satisfactory, but 2 patients died. In our center, the EPS survival rate was 60%. In patients treated with TPN alone, the remission rate was only 33.3%. Administration of CSs could not improve that rate. In 6 patients treated with surgery, the mortality rate was 33.3%. When EPS symptoms are not ameliorated by CS and TPN, surgical treatment should be considered. To prevent EPS, high-risk patients who have more than 72 months on CAPD and who have a high-transport peritoneum should discontinue CAPD.

Biological Transport↗
PubMed2002

Risk factors and preventive measures for encapsulating peritoneal sclerosis--Jikei experience 2002.

A growing incidence of encapsulating peritoneal sclerosis (EPS) has been reported recently in Japan, and it is now urgent to establish preventive measures against EPS development. In the present paper, we describe our observational results regarding the risk of EPS development and the characteristic features of patients with EPS, in terms of peritoneal morphology and peritoneal function as determined by peritoneal equilibration test. The ongoing working protocol for EPS prevention at Jikei University Hospital is also discussed. Our findings have revealed that long-term continuous ambulatory peritoneal dialysis (CAPD) is a risk factor for EPS development after transfer to hemodialysis from peritoneal dialysis (PD), and that, in most patients with EPS, peritoneal function is characterized by a longstanding high-transport state. The striking alterations in peritoneal morphology between patients with EPS and those with simple long-term CAPD hyperplasia include, in EPS patients, a prominent thickening of the collagenous layer of the peritoneum with neoangiogenesis and myofibroblastic transformation. Based on our findings, we established a withdrawal protocol for long-term CAPD patients, with the goal of preventing EPS. Those who have been on PD treatment for more than 72 months with high-transport state are candidates for withdrawal from PD, with performance of peritoneal lavage thereafter for a certain period of time. The clinical benefit of post-PD lavage has not yet been determined; however, the maneuver could be precluded in patients at low risk of EPS, because it was found that some patients can recover to average transport state during the period of PD withdrawal. Patients who remain high transporters with inflammatory reaction might require pharmacologic intervention, including prednisolone therapy. Further observations are required to validate our approach.

Adult↗
PubMedDate not supplied

Effects of L-threo-3,4-dihydroxyphenylserine on orthostatic hypotension in hemodialysis patients.

BACKGROUND: Orthostatic hypotension (OH) is a serious complication observed in hemodialysis (HD) patients after HD as well as during the interdialytic period. L-Threo-3,4-dihydroxyphenylserine (L-DOPS) is a nonphysiological neutral amino acid that is directly converted to the neurotransmitter norepinephrine by aromatic L-amino acid decarboxylase. METHODS: A placebo-controlled double-blind study for 4 consecutive weeks and a long-term study (24-52 weeks) were conducted to evaluate the efficacy of L-DOPS for OH after HD. The drug was administered orally 30 min before the start of each HD period in both studies. Doses of 400 mg of L-DOPS or placebo were given to HD patients with OH (45 and 41 patients, respectively) in the double-blind study, and doses of 200 or 400 mg of L-DOPS were given to 74 HD patients in the long-term study. RESULTS: In the double-blind study, L-DOPS significantly ameliorated subjective symptoms related to OH, including dizziness/light-headed feeling, and malaise, throughout the interdialytic period. For 19 patients with delayed-type OH, hypotension with the lowest blood pressure recorded 10 min after standing, the decrease in blood pressure was suppressed significantly after L-DOPS treatment (10 patients) as compared with the placebo-treated group (9 patients). In the long-term study, the efficacy of L-DOPS was not attenuated, and the marked fluctuations in the plasma L-DOPS and norepinephrine levels were not noted after long-term use, without increases in incidence or severity of adverse reactions. CONCLUSIONS: These results indicate that L-DOPS is effective for improving OH-related interdialytic subjective symptoms in HD patients after short-term as well as after long-term administration.

Autonomic Nervous System Diseases↗
PubMedDate not supplied

Association between an increased surface area of peritoneal microvessels and a high peritoneal solute transport rate.

OBJECTIVE: The peritoneal solute transport rate (PSTR) often increases, especially for small solutes, during long-term peritoneal dialysis (PD) treatment. Although the mechanism by which PSTR increases in PD patients is not known, it is likely that an increased PSTR reflects an increased surface area of the peritoneal capillary and post-capillary venules (microvessels), but this has not previously been investigated. The aim of this study was to clarify the relationship between PSTR and peritoneal microvessel alterations in biopsy specimens of peritoneum obtained from PD patients after various times on PD, and the possible contribution of the duration of PD in relation to these alterations. DESIGN: Tissue from the parietal peritoneum was obtained from 22 PD patients (age 48.5 +/- 9.0 years, duration of PD 66.3 +/- 46.6 months, incidence of peritonitis 0.3/patient-year). The patients were subdivided into three groups according to duration of PD: zero months (group 0, n = 4), less than 60 months (group I, n = 7), and more than 60 months (group II; n = 11). METHODS: For each specimen, the relative microvessel area (RVA) calculated as total area of microvessels/total area of peritoneal field, and the relative microvessel number (RVN), calculated as number of microvessels/total area of peritoneal field, were determined. The ratio RVA/RVN was used to assess the average area of microvessels. The PSTR was evaluated for creatinine, glucose, beta2-microglobulin, and albumin using the peritoneal equilibration test. RESULTS: The dialysate-to-plasma concentration ratio (D/P) for creatinine showed a significant positive correlation with both RVA (rho = 0.77, p < 0.001) and RVA/RVN (rho = 0.51, p = 0.01), but not with RVN. The D/P for beta2-microglobulin correlated with RVA (rho = 0.51, p = 0.015) but not with RVN or RVA/RVN. No differences were found between the three groups in the values for RVN, whereas there was an apparent significant increase in RVA with time on PD (p < 0.001 for group 0 vs both groups I and II). Furthermore, in high transporters, RVA tended to be higher in group II than in group I. CONCLUSIONS: The present study demonstrates for the first time that an increased peritoneal solute transport rate (for both creatinine and beta2-microglobulin) is associated with an increased surface area of peritoneal microvessels, especially in patients on long-term PD treatment. This indicates that increased vascularization and/or dilatation of peritoneal microvessels may play a key role in the development of a high PSTR.

Adult↗
PubMedDate not supplied

Is technique survival on peritoneal dialysis better in Japan?

Technique failure resulting in transfer to hemodialysis (HD) remains one of the most important challenges in Longterm peritoneal dialysis (PD). In general, the proportion of patients transferring from PD to HD is much greater than the proportion transferring from HD to PD. However, technique failure rates differ considerably between and within countries. The question arises as to how technique failure rates in Japan compare with those in other countries. To address this issue, we reviewed the literature and our experience of 139 incident continuous ambulatory peritoneal dialysis (CAPD) patients from January 1995 to December 1999. Based on our review, we estimate that the 5-year technique survival rate in Japanese CAPD patients is approximately 70%, and that technique failure rate is around 7% per year. This rate is significantly lower than that in many other countries. The most common reasons for technique failure in Japan are peritoneal membrane failure, ultrafiltration loss, and inadequate dialysis. Another factor contributing to the low technique failure rate in Japan is an extremely low peritonitis rate. This may be related to good sanitation and excellent PD training programs. Peritoneal membrane failure continues to be the major challenge for long-term technique survival on PD in Japan.

Humans↗