Yen Ts

Effect of intraperitoneally administered agents on human peritoneal mesothelial cell growth.

During continuous ambulatory peritoneal dialysis, the peritoneal mesothelial cell layer is under continuous sloughing and regeneration processes. Agents unfavorable for mesothelial cell growth may be harmful to the peritoneal membrane. We investigated whether frequent intraperitoneally instilled agents affect mesothelial cell growth. Peritoneal mesothelial cells were cultured from the human omentum. The proliferation was assessed by using a modified methyltetrazolium assay and confirmed by Coulter cell counting. The results showed that a high-glucose medium and heparin inhibited mesothelial cell growth. Cephalothin at the usual intraperitoneal loading and maintenance doses is toxic to mesothelial cells. Ceftazidime is toxic to mesothelial cells at its loading dose and inhibits growth at its maintenance dose. Aminoglycosides including netilmicin, gentamicin, and amikacin all had inhibitory effects at the loading and maintenance dose ranges. Vancomycin had no effect. The usual combinations of heparin and cephalothin with netilmicin or gentamicin as the initial treatment regimen for bacterial peritonitis are toxic to mesothelial cells. These results suggest that some intraperitoneal agents potentially may hamper mesothelial cell regeneration. The judicious use of heparin and the proper choice of antibiotic combinations may be warranted from the point of view of peritoneal protection.

The renal, cardiovascular and hemolytic actions in the rat of a toxic extract from the bile of the grass carp (Ctenopharyngodon idellus)

Grass carp bile, sometimes eaten by Chinese people, has previously been shown to induce acute renal failure in man and to result in the death of experimental mice and rats. A toxic extract from the bile acid fraction of grass carp bile (LD50 109 mg/kg) was injected into pentobarbitone anesthetized rats and an increase in urinary excretion of water and salts was produced. The bile extract also caused a prompt fall in systemic arterial blood pressure and cardiac output. It was also found, in vitro, that the bile salts caused a potent hemolysis. The hypothesis that hemoglobin is released from hemolysed red blood corpuscles and might be responsible for the long term renal functional damage is considered. Another alternative hypothesis is that the hypotension induced by the bile toxin may result in renal underperfusion and thus make the kidney more susceptible to the nephrotoxic action of the grass carp bile.

Effects of Intraperitoneal Antibiotics on Human Peritoneal Mesothelial Cell Growth

Peritonitis is one of the most frequent complications of continuous ambulatory peritoneal dialysis (CAPD). Necrosis and exfoliation of the mesothelial cell layer of the peritoneum develop during the acute phase of peritonitis. Agents that hamper regeneration of mesothelial cells will cause delayed recovery of the peritoneal surface, which results in continuous exposure of underlying stem cells to the stimulation of growth factors and possibly leads to peritoneal fibrosis syndrome. The aim of the present study is to determine the effects of several intraperitoneal antibiotics on human peritoneal mesothelial cell (HPMC) growth at their usual loading and maintenance doses. HPMCs were isolated from human omenta. Proliferation of HPMC was evaluated by modified methyltetrazolium assay and cell membrane integrity was assessed by lactate dehydrogenase method. The results showed that most cephalosporins exert an inhibitory, even toxic, effect on HPMCs at their loading doses. Cephalothin, cephradine, cefamandole, cefoxitin, cefuroxime and cefoperazone inhibited HPMC proliferation at their maintenance doses. Vancomycin, clindamycin, aztreonam, piperacillin, imipenem, tobramycin and ceftriaxone have no effect in their usual intraperitoneal doses. From the viewpoint of peritoneal protection, not only drug sensitivity of the causative microorganisms but also effects of antibiotics on HPMC regeneration should be considered when selecting antibiotics for CAPD peritonitis.

Continuous ambulatory peritoneal dialysis in the elderly: a seven-year experience.

This is a retrospective comparison of the status among the elderly (> or = 60 years, 23 patients) and younger patients (< 60 years, 31 cases) who initiated continuous ambulatory peritoneal dialysis (CAPD) between January 1986 and December 1992 at the National Taiwan University Hospital. The distribution of underlying renal diseases differed in the two groups with diabetes (56%) as the most common disease in the elderly, in contrast to glomerulonephritis (60%) in the younger patients. Haemodialysis intolerance and patient preference were the main reasons leading to the use of CAPD in both groups. Social rehabilitation status was poorer in the elderly group. The difference in cumulative risk of the first peritonitis episode and the technique failure rate were not statistically significant. The major causes of mortality were of vascular origin in both groups. In conclusion, similarities in the technique failure rate and the cumulative risk of peritonitis imply that CAPD is an acceptable alternative long-term dialysis therapy for geriatric patients.