Search

The aim of the present study was to describe the prevalence of all gastrointestinal (GI) symptoms reported by dialysis patients, as well as the tools being used for diagnosis. GI symptoms are commonly reported in patients having haemodialysis (HD) and peritoneal dialysis (PD), but there are multiple definitions and assessment tools reported in the literature.A comprehensive systematic review was undertaken using five databases (Embase, Medline, CINAHL, Psycinfo and Web of Science) between 1996 and 2017. Articles were critically appraised using the Newcastle Ottawa Scale (NOS). Data collected were analyzed in a Microsoft Excel spreadsheet.Thirty studies (24 cross-sectional, six cohort) met the inclusion criteria. In total 5161 patients were studied (3804 HD and 1507 PD). Fifteen studies included HD, five included PD and 10 included both dialysis modalities. GI symptoms were heterogeneous, with the reported prevalence highly dependent on the definitions used, inclusion/exclusion criteria, assessment tools and methods used. The most prevalent symptoms were constipation, indigestion, abdominal pain and reflux. Medication use and dietary data were poorly reported. The most common tools used were Gastrointestinal Symptom Rating Scale (GSRS), Rome II and Rome III. Constipation was more common in HD patients than PD patients. Indigestion, abdominal pain and reflux were commonly reported in both dialysis modalities.Gastrointestinal symptoms are highly prevalent in people on dialysis; however, the evidence base is limited and further investigation of preventable causes and potential interventions such as medications and diet are required in future research.

Objective L-Carnitine is an endogenous molecule involved in fatty acid metabolism. Secondary carnitine deficiency may develop in patients with end-stage renal disease undergoing long-term hemodialysis because of dialytic loss. In these patients L-carnitine can be administered to restore plasma and tissue levels. The objective of this study was to evaluate the pharmacokinetics of intravenous L-carnitine in patients undergoing long-term hemodialysis. Methods Twelve patients undergoing three dialysis sessions/week received L-carnitine intravenously (20 mg · kg−1) at the end of each dialysis session for 9 weeks. Plasma samples were analyzed for L-carnitine, acetyl-L-carnitine, and total carnitine by HPLC. Results Under baseline conditions, the mean ± SD predialysis plasma concentration of L-carnitine was 19.5 ± 5.6 μmol/L, decreasing to 5.6 ± 1.9 μmol/L at the end of the dialysis session. These concentrations were substantially lower than endogenous levels in healthy human beings. Under baseline conditions the extraction ratios of L-carnitine and acetyl-L-carnitine by the dialyser were 0.74 ± 0.07 and 0.71 ± 0.11, respectively. During repeated dosing, there was accumulation of L-carnitine in plasma, and after 9 weeks of dosing, the predialysis and postdialysis plasma levels were 191 ± 54.1 and 41.8 ± 13.0 μmol/L, respectively. The predialysis and postdialysis plasma levels of L-carnitine decreased once dosing was ceased but had not returned to pretreatment levels after 6 weeks. Conclusion The study demonstrated that removal of L-carnitine by hemodialysis is extremely efficient and that patients undergoing hemodialysis had plasma concentrations that were substantially lower than normal, particularly during dialysis. During repeated administration of L-carnitine, the predialysis and postdialysis concentrations of the compound increased steadily, reaching an apparent steady state after about 8 weeks. It is proposed that this accumulation arose from the distribution of l-carnitine into a deep tissue pool that includes skeletal muscle. Clinical Pharmacology & Therapeutics (2000) 68, 238–249; doi: 10.1067/mcp.2000.108850