Biomedical subjects

Naohiko Kato

Publications and source records attributed to Naohiko Kato.

6 recordsLinked to original sources

PubMed2005

[Dialysis as bridge therapy for renal transplantation: single center experience, a comparison of hemodialysis and continuous ambulatory peritoneal dialysis].

BACKGROUND: Kidney transplantation is the most ideal treatment in renal replacement therapy for patients with end-stage renal disease. However, the prevalence of transplantation is extremely low and most patients with ESRD should continue dialysis for their whole life. Recently, high transposition rate of renal transplantation from peritoneal dialysis (PD) was reported, however, it was unclear whether a difference in dialytic modality can influence the outcome. Therefore, we evaluated the influence of dialytic modality on the rate of kidney transplantation and outcome in our single center. METHODS: Forty-two kidney transplants were carried among 1,573 dialysis patients from the years 1986 to 2004 in our center. Transposition rates from two modalities (HD and PD) and graft survival were compared. The incidence of acute rejection episode, complications after receiving transplantations, and coexisting diseases were also evaluated between the two modalities prior to transplantation. RESULT: The number of patients who received HD was larger than PD (HD 77.1%, PD 22.9%, respectively). Forty-two patients undergoing dialytic therapy received a living-donor kidney transplantation. Overall graft survival was 92% at 5 years and 75% at 10 years. Among these cases, dialytic modality prior to transplantation was 57.1% in HD, and 42.9% in PD. The transfer rate from PD to transplantation was significantly (p = 0.0036) higher (4.7%) than that of HD (1.9%). The reason for the high transfer rate of PD patients might be cooperation with their family and the provision of relevant information by nephrologists during PD. There were no differences between the two modalities prior to transplantation in the graft survival rate, incidence of acute rejection, and complications before and after transplantation. CONCLUSION: Difference in pretransplant dialysis modality did not affect the outcomes, however, the transfer rate from PD was significantly higher than from HD. Accordingly, PD is useful compared to HD as bridge therapy for kidney transplantation from the high feasibility of living-donor kidney transplantation.

Adult↗

PubMed2004

Usefulness of radio-guided surgery using technetium-99m methoxyisobutylisonitrile for primary and secondary hyperparathyroidism.

The efficacy of technetium-99m methoxyisobutylisonitrile (99mTc-MIBI)-guided surgery for detecting abnormal parathyroid glands in patients with secondary hyperparathyroidism (2-HPT) was evaluated and compared with the results from the same examination in patients with primary hyperparathyroidism (1-HPT). The results were also compared with those found by ultrasonography (US) and preoperative 99mTc-MIBI scintigraphy was also made. At operation 99mTc-MIBI accumulated in 64 nodules of 15 cases of 2-HPT, and all of 60 parathyroid swellings were detected (true-positives 60, sensitivity 100%, accuracy 94%). In the cases of 1-HPT, 99mTc-MIBI revealed 11 hot nodules in 10 cases, and the evaluation was true-positive 10, sensitivity 100%, and accuracy 91%. US and preoperative 99mTc-MIBI scintigraphy in patients with 2-HPT had a sensitivity of 75% and 67% and an accuracy of 70% and 66%, respectively. The usefulness of 99mTc-MIBI-guided surgery for detecting abnormal parathyroid tissue in 2-HPT patients was similar to that in 1-HPT patients but was superior to US and preoperative 99mTc-MIBI scintigraphy. Intraoperative 9mTc-MIBI for patients with 2-HPT is effective and makes the surgery easier, especially when the parathyroid glands are ectopic or when a few glands are markedly enlarged but the other glands are atrophied.

Adult↗

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

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↗