Does amino acid-based peritoneal dialysate change homocysteine metabolism in continuous ambulatory peritoneal dialysis patients?
OBJECTIVE
We examined whether amino acid-based peritoneal dialysate that contains 85 mg/dL L-methionine affects homocysteine (Hcy) metabolism.


METHODS
The study enrolled 17 adult CAPD patients (11 men, 6 women) who had been receiving CAPD for at least 6 months and who had low serum albumin levels (<3.7 g/dL). Diet was not specifically changed. All of the study patients received daily 4-exchange CAPD treatment, and they used Nutrineal (Baxter Healthcare, Deerfield, IL, U.S.A.) as one of their daily exchanges (first or second exchange). Blood samples were collected every 2 weeks, and Hcy was measured.


RESULTS
After use of Nutrineal, serum albumin was unchanged, but blood urea nitrogen (BUN) and total protein were increased. Before the study began, 1 patient had a very high Hcy level (256 micromol/L); his data were excluded from the analysis. In the remaining 16 patients, baseline Hcy was 24.4 +/- 7.0 micromol/L. Levels of Hcy progressively increased with the use of Nutrineal: 28.1 +/- 6.2 micromol/L in week 2, 28.4 +/- 7.1 micromol/L in week 4, 29.1 +/- 7.6 micromol/L in week 6, 29.3 +/- 9.0 micromol/L in week 8, 27.5+/-9.7 micromol/L in week 10, and 30.3 +/- 8.2 micromol/L in week 12.


CONCLUSIONS
Nutrineal might help to replenish daily protein loss, but it also increased formation of Hcy and, therefore, the potential risk of cardiovascular illness. Further studies will be needed to examine the effect of folic acid and vitamin B(12) supplementation in the rescue of that Hcy increase, and also a possible correlation with methylenetetrahydrofolate reductase gene polymorphism.
Chang
Jer-Ming
JM
Department of Nephrology, Kaohsiung Medical University, Kaohsiung, Taiwan.
Chen
Hung-Chun
HC
Hwang
Shang-Jyh
SJ
Tsai
Jer-Chia
JC
Lai
Yung-Hsiung
YH
D000293:Adolescent; D000328:Adult; D000368:Aged; D000596:Amino Acids / Q000494:pharmacology*; D005260:Female; D015312:Hemodialysis Solutions / Q000008:administration & dosage / Q000494:pharmacology*; D006710:Homocysteine / Q000097:blood / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000494:pharmacology*; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D055815:Young Adult
D000596:Amino Acids; D015312:Hemodialysis Solutions; C482915:Nutrineal; D006710:Homocysteine; D008715:Methionine