Diagnostic value of plasma asymmetric and symmetric dimethylarginine levels in liver transplant recipients.

INTRODUCTION: Nitric oxide is an important factor in the pathogenesis of liver cirrhosis. Its synthesis depends on the availability of L­arginine and is inhibited by asymmetric dimethylarginine (ADMA). Symmetric dimethylarginine (SDMA) seems to be a good marker of multiorgan failure, especially renal failure. OBJECTIVES: The aim of the present study was to evaluate the diagnostic significance of dimethylarginines in patients after liver transplantation. PATIENTS AND METHODS: The study included 30 cadaver liver donors and 30 recipients with liver cirrhosis. The following parameters were estimated in donors and in liver recipients before and at days 1 and 3 after transplantation: serum alanine transaminase (ALT), aspartate transaminase (AST), and γ­glutamyltranspeptidase (GGT) activity, international normalized ratio (INR), concentrations of bilirubin, albumin, creatinine, electrolytes, ADMA, SDMA, and L­arginine. RESULTS: Before transplantation cirrhotic patients showed higher bilirubin concentrations, higher ALT and GGT activity, and lower sodium and albumin levels compared with donors. At day 3 after transplantation, we observed a significant increase in ALT, AST, creatinine, sodium, ADMA, SDMA, and L­arginine, and a decrease in bilirubin levels. A significant positive correlation between SDMA and creatinine was found in donors (P <0.001), recipients before transplantation (P <0.0005), and at days 1 (P <0.004) and 2 after transplantation (P <0.0005). A significant positive correlation was also observed before transplantation between ADMA and bilirubin concentrations (P = 0.0264), ADMA and albumin concentrations at day 1 after transplantation (P = 0.02), while a negative correlation was observed between ADMA and INR before transplantation (P = 0.008) and at day 3 after transplantation (P = 0.03) in recipients. CONCLUSIONS: An increase in dimethylarginine levels after liver transplantation seems to be due not only to the dysfunction of the transplanted liver, but also to impaired kidney function caused by the surgery itself and/or the use of a nephrotoxic calcineurin inhibitor--tacrolimus. A significant correlation between serum creatinine and SDMA concentrations both in liver donors and recipients suggests that SDMA renal clearance may have diagnostic value to evaluate the glomerular filtration rate in these patients.

[Prevalence of anemia, calcium-phosphorus abnormalities and metabolic acidosis in different stages of chronic renal failure]. / Stopien niewydolnosci nerek a czestosc wystepowania niedokrwistosci, zaburzen gospodarki wapniowo-fosforanowej oraz kwasicy metabolicznej.

BACKGROUND: Chronic kidney disease (CKD) is associated with the reduction of haemoglobin concentration and a variety of biochemical abnormalities including changes in serum concentration of sodium, potassium, calcium, phosphate, bicarbonate, and hydrogen ions. However, data concerning epidemiology of these abnormalities are rare and incomplete, especially among subjects with mild to moderate CKD. PATIENTS AND METHODS: Patients with a serum creatinine concentration > 110 micromol/l hospitalized in the Department of Nephrology, Endocrinology and Metabolic Diseases Medical University of Silesia from 1998 to 2002 were analyzed. Patients with acute renal failure or chronic renal failure treated with renal replacement therapy were excluded from this study. A total of 653 patients (262F and 391M) were divided into 9 subgroups differing from each other by progressive decline of glomerular filtration rate (GFR). RESULTS: A statistically significant decrease in haemoglobin concentration and increase in the prevalence of anaemia were found in patients with GFR < 50 ml/min. In a large number of patients with a GFR < 80 but > 50 ml/min, Hb concentration <11 g/dl was observed. Mean MCV, MCH and serum iron concentration were similar in all studied subgroups. A progressive increase in serum phosphorus concentration and decrease of calcaemia was found in patients with GFR < 30 ml/min. The elevated Ca x P product (> 4.44 mmol2/12) was noticed almost exclusively in patients with GFR< 30 ml/min. A decompensated metabolic acidosis was observed in 29.8% of patients with GFR <30 ml/min. CONCLUSIONS: Anaemia is an early symptom of chronic kidney disease preceding disturbances of calcium, phosphate and hydrogen ions metabolism. These abnormalities seem to be of therapeutic relevance.