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Otto Schück

Publications and source records attributed to Otto Schück.

8 recordsLinked to original sources
PubMed2005

Relation between pH and the strong ion difference (SID) in body fluids.

Acid-base balance evaluation according to the Henderson-Hasselbalch equation enable us to assess the contribution of respiratory (pCO2) and/or non-respiratory (metabolic, HCO3(-)) components to the acid-base balance status. A new approach to acid-base balance evaluation according to Stewart-Fencl, which is based on a detailed physical-chemical analysis of body fluids shows that metabolic acid-base balance disorders are characterized not only by [HCO3(-)]. According to this concept independent variables must be taken into an account. The abnormality of concentration of one or more of the independent variable(s) determines the pH of a solution. The independent variables are: 1. strong ion difference (SID); 2. total concentration of nonvolatile weak acids [A(tot)]; 3. in agreement with the Henderson-Hasselbalch concept also pCO2. Traditional evaluation of acid-base balance disorders is based on the pH of body fluids (though pH may be within normal range if several acid-base balance disturbances are present). In order to maintain this view and simultaneously to respect the Stewart-Fencl principle, we invented a new equation, which uses only the independent variables to define the pH of body fluids. This analysis shows that for a given value of pCO2, the pH of body fluids is determined by a difference between SID and [A(tot)-]. pH = 6.1 + log((SID - [A(tot)-])/(0.03pCO2)) or in itemized form: pH = 6.1 + log((([Na+] + [K+] + [Ca2+] + [Mg2+] - [Cl-] - [UA-]) - (k1[Alb] + k2[P(i)]))/(0.03 x pCO2)). Evaluation of the individual components of this equation enables us to detect, which of the independent variable (or a combination of independent variables) deviates from the normal range and therefore which one or ones is a cause of the acid-base balance disorder. At the end of this paper we give examples of a practical application of this equation.

Acid-Base Equilibrium↗
PubMed2003

Enhanced metabolic effect of erythropoietin and keto acids in CRF patients on low-protein diet: Czech multicenter study.

BACKGROUND: Our study is designed to establish whether supplementation with erythropoietin (EPO) exerts additional beneficial metabolic effects in patients with chronic renal failure (CRF) treated with keto acids (KAs) on a low-protein diet (LPD). METHODS: A long-term, prospective, randomized study was designed to use three therapeutic protocols: (A) EPO plus KAs plus LPD (group I), (B) EPO plus LPD (group II), and (C) LPD (group III). One hundred eighty-six randomly selected patients (90 men, 96 women; age, 22 to 78 years) with a creatinine clearance of 22 to 36 mL/min were monitored at the beginning and at every 6 months for 3 years. RESULTS: During the study period, glomerular filtration rate measured as inulin clearance decreased slightly (from 26.2 +/- 3.4 to 23.4 +/- 4.1 mL/min in group I), 27.4 +/- 4.8 to 20.2 +/- 4.4 mL/min in group II, and 26.8 +/- 3.6 to 17.4 +/- 4.1 mL/min in group III; P < 0.01). Serum urea levels also declined (P < 0.01), more pronouncedly in group I (P < 0.025). In group I, there was a significant increase in levels of leucine (P < 0.01) and albumin (P < 0.01) and a decrease in proteinuria (P < 0.01). Analysis of the lipid spectrum showed a mild, yet significant, decrease in total cholesterol and low-density lipoprotein cholesterol levels (P < 0.025), more pronounced in group I. In group I, there was a decrease in plasma triglyceride levels (from 362.85 +/- 115.05 mg/dL [4.1 +/- 1.3 mmol/L] to values as low as 203.55 +/- 70.80 mg/dL [2.3 +/- 0.8 mmol/L]; P < 0.01), whereas high-density lipoprotein cholesterol levels increased (from 34.75 +/- 7.72 mg/dL [0.9 +/- 0.2 mmol/L] to 46.33 +/- 7.72 mg/dL [1.2 +/- 0.2 mmol/L]; P < 0.025). Mean arterial blood pressure was stable. CONCLUSION: EPO supplementation in patients with CRF administered KAs potentiates the beneficial effects on metabolism of proteins, amino acids, and lipids. Long-term coadministration of EPO, KA, and LPD was associated with a delay in progression of renal failure and reduction in proteinuria.

Adult↗
PubMed2003

Obesity and hyperhomocysteinaemia after kidney transplantation.

Obesity and hyperhomocysteinaemia are found very frequently after kidney transplantation (Tx). They may independently represent risk factors for development of atherosclerosis and chronic allograft nephropathy. In a prospective metabolic study, we monitored, over a period of 24 months, a total of 118 obese transplant patients [body mass index (BMI) > or =30 kg/m(2)] with hyperhomocysteinaemia. We compared the findings of a new therapeutic regimen at 1 year (start of the study) and 2 years after renal transplantation. Based on a Subjective Global Assessment Scoring Sheet, we started at the end of the first year with an individualized hypoenergic-hypolipidaemic diet (IHHD). Subsequently, after corticoid withdrawal, IHHD was supplemented regularly with orlistat at a dose of up to 3 x 120 mg/day, statins (pravastatin 10-40 mg), folic acid 5 mg/day and vitamin B6 50 mg/day, and followed-up for up to 2 years. All patients were on a regimen of cyclosporin A and mycophenolate mofetil. During the study period, there was a significant decrease in BMI (P < 0.025) and total homocysteine level (P < 0.001). Long-term therapy was associated with a significant decrease in serum leptin (P < 0.001) and lipid metabolism parameters (P < 0.01). The mean values of serum folate and vitamin B6 also increased significantly (P < 0.01); creatinine clearance, mean blood pressure, proteinuria, lipoprotein(a) and apolipoprotein E isoforms did not differ significantly. Based on our results, we assume that obesity and hyperhomocysteinaemia after renal transplantation can be treated effectively by modified immunosuppression (corticosteroid withdrawal), long-term diet (IHHD), folic acid and vitamin B6 supplementation, and drugs suppressing digestion or absorption to reduce atherosclerotic and chronic allograft nephrop-athy processes.

Adult↗
PubMed2003

Glomerular filtration rate estimation in patients with advanced chronic renal insufficiency based on serum cystatin C levels.

BACKGROUND: Cystatin C has an obvious advantage in the recognition of the initial stages of renal impairment. It is questionable whether cystatin C possesses the same benefit in follow-up of pre-dialysis patients. If cystatin C were also a sensitive marker of GFR in pre-dialysis patients, then it could be expected that, for the same degree of a decrease in GFR, the increase in S(cyst) would be higher than in S(cr) because of the significant increase in tubular secretion of creatinine in residual nephrons. The aim of this study was to evaluate whether S(cyst) in patients with GFR <or=40 ml/min/1.73 m(2) provides a more accurate estimate of GFR than S(cr) does. METHODS: The study was performed in 67 patients (mean age 41.5 +/- 7.6 years) with chronic renal insufficiency (GFR = 19.8 +/- 9.9 ml/min/1.73 m(2)) caused by various chronic renal diseases (predominantly by chronic glomerulonephritis and chronic interstitial nephritis). GFR was measured by inulin clearance under conditions of stabilized plasma concentrations and water loading. Creatinine clearance and serum cystatin C concentration (using immunonephelometry) were measured at the same time. For statistical evaluation, linear regression analysis, receiver-operating characteristic (ROC) curves analysis and the method of Bland and Altman were used. RESULTS: A significant correlation (r = 0.813, p < 0.001) was demonstrated between 1/S(cyst) and C(in) as well as between 1/S(cr) and C(in) (r = 0.815, p < 0.001). There were no significant differences between the regression coefficients and the intercepts of regression straight lines characterizing these relationships. ROC curves analysis using the cut-off values for C(in) = 20 ml/min/1.73 m(2) and C(in) = 10 ml/min/ 1.73 m(2) did not show significant differences of corresponding AUC values for S(cyst) and S(cr) although there was a trend for superiority of S(cyst) in comparison with S(cr). The multiples of upper reference values of S(cyst) and S(cr) in examined patients did not differ significantly. There was a highly significant linear correlation between C(in) and C(cr) in pre-dialysis patients (r = 0.921, p < 0.001). The regression coefficient of this relation (1.279) was significantly higher than 1.0 (p < 0.001) and the value of intercept (6.50 ml/min/1.73 m(2)) was significantly higher than zero (p < 0.001). The average of C(cr)/C(in) in patients with C(in) <10 ml/min/1.73 m(2) was 2.11 (+/- 0.29) and 1.72 (+/- 0.35) for those with C(in) 10-20 ml/min/1.73 m(2). CONCLUSIONS: The findings suggest that in patients with advanced chronic renal insufficiency (CRI) for the same decrease in GFR the increase of S(cyst) is not significantly higher than that of S(cr), although the tubular secretion of creatinine is significantly increased. Further studies (especially those focused on nonrenal elimination of cystatin C) are needed to elucidate the lack of difference between changes in S(cyst) and S(cr) in patients with CRI.

Adolescent↗
PubMed2003

Predicting the grade of Banff 97 classification of chronic allograft nephropathy based on examination of graft dysfunction (a preliminary report).

OBJECTIVES: Progression of chronic allograft nephropathy (CAN) is associated with a progressive decrease in graft function. Prediction of the Banff CAN grade on the basis of correlation between the grade of histological changes and Scr is difficult because of the big spread of individual values. This study sought to predict the Banff CAN grade based on Scr, Ccr and proteinuria using ROC analysis. METHODS: Graft protocol biopsy and functional testing (Scr, Ccr and proteinuria) were performed in 77 subjects (43 men, 34 women, mean age 48.4 +/- 12.8 years) at 33.8 +/- 1.0 months after their first renal transplantation. Immunosuppression was provided with the triple combination of cyclosporin A, prednisone and azathioprine (or mycophenolate mofetil). Statistical evaluation was performed using receiver-operating curve (ROC) analysis. The cut-off value of the Banff CAN score was set at 1. RESULTS: The mean values and SD of the investigated functional parameters in study subjects were as follows: Scr = 201.5 (+/- 100.0) mumol/l Ccr = 48.1 (+/- 21.2) ml/min/1.73 m2, proteinuria = 0.89 (+/- 1.96) g/24 h. ROC analysis showed the highest AUC (+/- SEM) for Scr 0.806 (+/- 0.063). The respective values were 0.790 (+/- 0.053) for Ccr and 0.643 (+/- 0.075) for proteinuria. The AUC (area under the ROC curve) for Scr was significantly higher (P < 0.043) compared with proteinuria. The values for sensitivity (specificity) were as follows: Scr 65.0 (91.2). Ccr 75.0 (82.5), proteinuria 60.0 (68.4). The best fit values (best combination of sensitivity and specificity) were 257.2 umol/l for Scr, 33.6 ml/min/1.73 m2 for Ccr and 0.40 g/24 hr for proteinuria. CONCLUSIONS: Our findings support the assumption that Scr > 275 mumol/l and Ccr < 33.6 ml/min/1.73 m2 suggest a Banff CAN grade higher than 1 (P < 0.001). Proteinuria had the lowest predictive values. Values > 0.40 g/24 hr were probably associated with a Banff CAN grade higher than 1 (p < 0.05).

Biopsy↗
PubMed2002

Estimated and measured donor creatinine clearance are poor predictors of long-term renal graft function and survival.

The objective of this study was to evaluate estimated and measured donor renal function in predicting graft function long-term and to identify donor criteria associated with nonacceptable graft prognosis. In 200 consecutive cadaver donors creatinine clearance was measured at explantation and estimated using the Cockcroft formula on admission serum creatinine. Graft function was evaluated in recipients (n = 387) by 24-h creatinine clearance regularly during 3 years after transplantation. Measured creatinine clearance correlated to some extent with long-term graft function, while Cockcroft estimation was slightly superior and similar to using donor age only. Kidneys from donors with intra-operative creatinine clearance < or = 55 mL/min (median 50 mL/min) produced acceptable recipient graft function of 48 mL/min at 3 years and 76% 3-year graft survival. Donor age > or =60 years resulted in clearance at 3 years of 29 mL/min and 78% 3-year graft survival; adding the criteria of admission Cockcroft < or =60 mL/min, graft function at 3 years (28 mL/min) and 3-year graft survival (76%) were similar. In conclusion, creatinine-based estimates of the functional capacity of the donor kidney, calculated or intra-operatively measured, do little to improve the ability of donor age alone to predict long-term allograft function after renal transplantation, and nonacceptable donors are not discriminated.

Adult↗
PubMed2002

Glomerular filtration rate assessment in individuals after orthotopic liver transplantation based on serum cystatin C levels.

Individuals after orthotopic liver transplantation (OLT) often show renal dysfunction, which may substantially affect the post-OLT course. Renal function after OLT is commonly assessed by means of serum creatinine (S(cr)) concentration or renal creatinine clearance (C(cr)). A glomerular filtration rate (GFR) estimate based on S(cr) level is not accurate enough because even a more marked decrease in GFR need not be associated with an increase in S(cr) level, especially in jaundiced patients. The study intends to try to estimate GFR in individuals after OLT by means of determining serum cystatin C (S(cyst)) concentrations. In 58 individuals (mean age, 49 +/- 7 years; 31 men, 27 women) at various intervals from OLT (mean, 14 +/- 10 months), GFR was estimated by using simultaneous determinations of S(cyst), S(cr), C(cr), and renal inulin clearance (C(in)). In most subjects (91.3%), C(in) was decreased to less than the lower limit of normal (80 mL/min/1.73 m(2)). A significant correlation (r = 0.70; P <.001) was found between 1/S(cyst) and C(in). Receiver operating characteristic analysis was performed on S(cyst) and S(cr) using a C(in) cutoff value of 80 mL/min/1.73 m(2). The area under the curve for S(cyst) was 0.912 +/- 0.044, and that for S(cr), 0.899 +/- 0.049. There was no statistically significant difference between these values. The sensitivity for a S(cyst) level of 1.20 mg/L (upper limit of normal value) to detect a decrease in GFR (measured as C(in)) below the lower limit of normal (80 mL/min/1.73 m(2)) was 96.1%. The sensitivity of S(cyst) level was significantly greater (P <.01) than the sensitivity of S(cr) level for men and at borderline significance for women (P =.05). Findings support the assumption that a S(cyst) level less than 1.2 mg/L indicates with a high degree of probability (P <.001) that GFR is not decreased to less than the normal limit. S(cyst) assessment in individuals after OLT could be proposed as a confirmatory test of a decrease in GFR in individuals with normal S(cr) levels.

Adolescent↗