Lipid-lowering effect of carnitine in chronically uremic patients treated with maintenance hemodialysis.

Hypertriglyceridemia is often present in chronically uremic patients treated with maintenance hemodialysis and has been considered a risk factor in the accelerated development of atheroma. Muscle carnitine content is low in hemodialyzed patients. This abnormality may help to explain the myopathy and cardiomyopathy often observed in these subjects. In addition, carnitine might play a role in the hypertriglyceridemia in renal failure. Carnitine, which is necessary for fatty acid oxidation, has been recently reported to lower serum triglycerides in patients with type IV hyperlipoproteinemia. Carnitine was administered intravenously three times weekly at the end of hemodialysis in eight patients. Carnitine was given in 0.5 g doses for 8 weeks and then in 1.0 g doses for 6 additional weeks. There was a significant decrease in serum triglycerides at the end of treatment. In contrast, serum lipids in eight hemodialysis patients receiving placebo did not change significantly. Carnitine administration does not cause any side effect except some euphoria. These results suggest that carnitine may be effective in the treatment of hypertriglyceridemia in dialysis patients.

A new technique of continuous ambulatory peritoneal dialysis (CAPD): double-bag system for freedom to the patient and significant reduction of peritonitis.

A new technical approach has been described for the treatment of patients on CAPD. The new approach is based on the use of a two-bag system and closed connection by a connector to the Tenckhoff catheter. After each dialyzate exchange the patient discards the entire system and is completely bag-free, unlike the Oreopoulos CAPD technique. Using this new procedure we have markedly reduced the incidence of peritonitis and we have made the patient free from carrying an uncomfortable burden during the interval of solution exchange.

Continuous ambulatory peritoneal dialysis without wearing a bag: complete freedom of patient and significant reduction of peritonitis.

Despite the great impact of continuous ambulatory peritoneal dialysis (CAPD) as an effective modality of treatment for uraemic patients, two limiting factors remain: the high incidence of peritonitis and the need for patients continuously to carry a bag. We have designed a new closed system with two bags connected to the permanent Tenckhoff catheter. Two clamps alternately allow outflow and inflow of peritoneal dialysate. When the exchange manoeuvre is finished the patient frees the whole system from the needle and discards it. Since December 1978, 24 patients have been treated with this technique. The results are similar to the Toronto series with a marked reduction in the incidence of peritonitis (22.5 pt/months).

Lecithin-cholesterol acyltransferase (LCAT) activity in chronic uremia.

High plasma concentrations of triglycerides and low plasma concentrations of esterified cholesterol and lysolecithin, with an impaired rate of VLDL and LDL catabolism, have been reported in chronic uremic patients. An important contribution to these abnormalitites might be an impaired activity of the (LCAT). Serum LCAT activity and cholesteryl ester clearance were determined in 11 patients with chronic renal failure and in 10 controls. LCAT activity was determined by using the serum of each patient both as a source of enzyme and as a substrate ("intrinsic" activity) and was compared with the activity determined on a standard substrate ("extrinsic activity), so as to ascertain the presence of inhibitory factors in the patients' sera. Both activityes have been found to be significantly (P less than 0.01) lower in chronic uremic patients than in controls. The cholesteryl ester clearance apparently did not respond to the stimulatory effect of hypertriglyceridemia, as observed in other cases of dislipoproteinemias. The parallel decrease of both enzyme activities makes it unlikely that it is due to the presence of "uremic toxins" inhibiting the enzyme activity. LCAT synthesis in the liver is probably reduced in chronic uremia. These results suggest that in chronic uremia the VLDL fail to cooperate in their own catabolism.