Abstract: Uremic pruritus is a common symptom in patients undergoing hemodialysis (HD) or peritoneal dialysis, but its exact pathogenesis remains rather unclear. However, severe or "intractable" pruritus may be the manifestation of another underlying disease or disorder other than uremia. Delusional parasitosis, or Ekbom syndrome, is a rare psychiatric disorder characterized by the false conviction of being infested with parasites, and it can be primary, or secondary to several medical and psychiatric disorders. We report 2 elderly HD patients who presented one after another, with delusional parasitosis. At some point in time, the delusional beliefs of the first patient were adopted by the second patient who was waiting to start his HD session on the same bed and HD machine, on a subsequent shift. They were both diagnosed with Ekbom syndrome and described as having monosymptomatic hypochondriac delusion. They were both prescribed antipsychotic medications. During follow-up they admitted feeling better than before; however, they remained concerned about the "insects/parasites."
Abstract: Ezetimibe is a hypolipidemic agent acting via inhibition of cholesterol absorption from the small intestine. The effectiveness and safety of long-term administration of ezetimibe was evaluated in renal allograft recipients with persistent hyperlipidemia.
Abstract: The knowledge about the exact mechanisms involved in phosphorus homeostasis and the evolution of secondary hyperparathyroidism in chronic kidney disease (CKD) has improved during the last years. The discovery of Fibroblast Growth Factor 23 (FGF23) has revolutionized our understanding about the links between mineral metabolism, vitamin D and parathyroid hormone (PTH). FGF23 serum levels increase early in CKD before the increase of serum phosphorus or the decrease of vitamin D and there is parathyroid resistance to FGF23 in advanced CKD. Increased levels of serum phosphorus have been related in epidemiological studies with adverse outcomes in patients with CKD, diabetes, coronary artery disease, or even normal adults. In patients with CKD stage 3 or 4, low phosphorus diets have been related with adverse outcomes due to the risk of malnutrition and there are limited data regarding the role of phosphate binders in these patients. Recent studies suggest that increased serum FGF23 levels are associated with mortality, left ventricular hypertrophy and progression of CKD independently of serum phosphorus levels. There is an ongoing debate about the "normal" or "desirable" levels of serum phosphorus in CKD and a new role of FGF23 as a marker of the disturbances of mineral metabolism in CKD is emerging.
Abstract: Recent studies indicate that regulatory T-cells (Tregs) promote transplant tolerance. We studied Treg levels in 39 stable renal transplant recipients to determine the sizes of the Treg populations and the effects of treatment regimens thereof.
Abstract: The aim of the present study was to investigate psychosocial variables related to objective and subjective indicators of quality of life in a single center cohort study of patients undergoing in-center hemodialysis (HD), Continuous Ambulatory Peritoneal Dialysis (CAPD) and renal transplant recipients (RTx). We studied 40 HD patients, 36 CAPD, and 48 RTx patients by a special questionnaire examining demographics, functional status, employment status, and impact of therapy on psychosocial issues such as anxiety and depression. The RTx patients disclosed a better functional and employment status than the CAPD and the HD patients. They were also more compliant and satisfied with their therapy and their relationship with the medical and nursing personnel. The CAPD patients were also more satisfied, more compliant, better motivated, and less anxious and depressed compared with the HD patients who scored low in every aspect studied. Successful renal transplantation is a superior modality of therapy than HD or CAPD regarding psychosocial and quality of life issues. However these results can partially be explained by some selection bias, as RTx patients are usually younger and CAPD patients are selected for this modality after examining functional and social status.
Abstract: Hospital-based intermittent peritoneal dialysis (IPD) is an old PD modality applied for as long as 40 h per week using high volumes of PD fluid, but it has almost been abandoned due to its low solute clearances. However, IPD might be the only option for elderly dialysis patients with significant comorbidities, unable to undergo haemodialysis (HD) or PD at home without any assistance, for various reasons.
Abstract: Eosinophilic peritonitis following peritoneal dialysis catheter insertion is an infrequent but important complication. While allergic reaction to catheter material has been noted to be a culprit, air infusion into the abdominal cavity has also been highlighted to be a cause of this complication. In this article, we report two patients with end-stage renal disease where air entrapment in the peritoneal cavity during a peritoneal dialysis catheter insertion resulted in eosinophilic peritonitis. The complication resolved with the reabsorption of entrapped intraperitoneal air and treatment with ketotifen. Peritonitis observed in the postoperative period during the peritoneoscopic insertion of a peritoneal dialysis catheter could be the result of air entrapment. Such patients might not require antibiotic therapy or catheter removal. Reabsorption of entrapped air and treatment with ketotifen might be all that is required.
Abstract: The role of microchimerism in peripheral blood and urine of renal transplant recipients remains a matter of debate, depending on the sensitivity of the methods used for detection. We studied 17 female renal transplant recipients who had received renal allografts from male donors. Polymerase chain reaction (PCR) was applied to blood and urine for the microsatellite markers D1S80, DYZ1, TH01, and kalphai SE33. Detection of DYZ1 that is present only on the Y chromosome was considered proof for microchimerism. No microchimerism was detected in peripheral blood, whereas it could be detected in the urine of 8/17 (48%) patients. There were no differences between patients with and without microchimerism regarding patient age, dialysis vintage, immunosuppression, time post-transplantation, and allograft function as measured using serum creatinine, creatinine clearance, and proteinuria. Two patients in each group showed chronic allograft dysfunction. These findings raise questions regarding the role of microchimerism in renal transplantation.
Abstract: One of the main goals of dialysis is the control of extracellular volume, because inadequate sodium and fluid removal result in fluid overload and increased mortality. In the present study, we evaluated the roles of continuous ambulatory peritoneal dialysis (CAPD), continuous cycling peritoneal dialysis (CCPD), and the use of icodextrin on sodium removal in 29 patients (n = 18 on CAPD, n = 11 on CCPD). Daily removal of sodium by each modality and dialysis adequacy by Kt/V and creatinine clearance were evaluated. A significantly higher amount of sodium was removed in CAPD patients than in CCPD patients, although peritoneal dialysis clearances were lower in CAPD, and no difference in daily ultrafiltration was observed between the modalities. In the CAPD group, patients using icodextrin for the long dwell showed significantly increased 24-hour sodium removal (218 +/- 65 mmol/L) as compared with patients not using icodextrin (96.3 +/- 58 mmol/L, p < 0.001); they also showed increased daily ultrafiltration (1685 +/- 302 mL vs. 717 +/- 440 mL, p < 0.001). In the CCPD group, 8 patients were using icodextrin for the long dwell, and they showed significantly increased sodium removal only for the day exchange (43 +/- 49 mmol/L) as compared with patients not using icodextrin (-60 +/- 6, p < 0.001). Hypertension was less common in the CAPD patients than in the CCPD patients. These results indicate that CAPD is a more efficient modality than CCPD for sodium removal. Icodextrin is an effective tool not only for increasing adequacy, but also for removing more sodium in both modalities.
Abstract: Peripheral artery stiffness is altered in diabetic patients with end-stage renal disease (ESRD), whereas few data exist to confirm this trend for proximal aortic stiffness. The pulse wave velocity of the proximal aorta (PWVr) and of the carotid-to-femoral aortic segment (PWVcf) were determined by ultrasound imaging in 160 patients with ESRD (70 diabetic) and in 160 matched control subjects. Also, plasma levels of endothelin, homocysteine, and high-sensitivity C-reactive protein were determined in both groups. Patients with ESRD had increased pulse pressure, left ventricular (LV) end-diastolic diameter, LV mass index, PWVr, and PWVcf compared with control subjects (p < 0.05). Diabetic patients had increased LV mass index, PWVr, and PWVcf compared with nondiabetic patients with ESRD (p < 0.05). Endothelin levels exhibited a strong relation with PWVr (r = 0.32, p < 0.001) and PWVcf (r = 0.33, p < 0.001) measurements in ESRD patients. Multivariate linear regression analysis revealed that age, diabetes, and plasma levels of endothelin were major determinants of increased PWVr measurements in the total ESRD population. After adjustment for age, body surface area, time on dialysis, systolic blood pressure, history of hypertension, and plasma endothelin levels, diabetes was an independent factor associated with PWVr in ESRD subjects. Diabetic patients with ESRD had significantly increased proximal aortic stiffness and significantly altered plasma levels of endothelin as compared with the nondiabetic.
Abstract: A 43-year old Caucasian male with end-stage renal disease presented with painful skin lesions and high calcium phosphate product that did not respond to medical treatment. Skin biopsy confirmed the diagnosis of calciphylaxis. Urgent parathyroidectomy was performed and resulted in decrease in the calcium phosphate product and improvement of his symptoms and signs.
Abstract: Hemodialysis patients experience a variety of hemodynamic abnormalities that contribute to cardiovascular disease mortality which is the leading cause of death in these patients. Impedance cardiography has been utilized in order to monitor cardiac hemodynamics with lower cost and inconvenience, but it has not been appropriately validated in the hemodialysis population.
Abstract: The timing of the first episode of peritonitis in peritoneal dialysis (PD) might have some special characteristics and may depend on many factors such as a patient's attitudes, age, comorbidity, or training capacity. It may also have a significant impact on further peritonitis episodes and technique failure. We retrospectively analyzed data for 168 PD patients who were undergoing continuous ambulatory PD by a twin-bag system, automated PD, or in-center intermittent PD over 12 years. There were 121 cases of peritonitis recorded in 60 patients, with an overall peritonitis rate of 1 episode per 45.75 patient-months. The mean time to the first episode of peritonitis after commencement of PD was 26.4 +/- 22 months (range: 1-110 months). In 20 patients, a first peritonitis episode presented rather early--during the first 12 months on PD (group A)--and in 27 patients, a first episode presented rather late-after at least 24 months on PD (group B). Group A had lower technique survival (30.4 +/- 26.5 months), were more prone to further episodes of peritonitis during follow-up, and had a total peritonitis rate of 1 episode per 14.85 patient-months. In group B, technique survival was longer (69.3 +/- 33.8 months), and the total peritonitis rate was 1 episode per 45.68 patient-months. We observed no differences between the two groups in comorbidity, age, or PD modality. These results indicate that patients with early-onset peritonitis are prone to making mistakes during connection, resulting usually in infection with gram-positive pathogens. These patients may present repeated peritonitis episodes and experience decreased technique survival.
Abstract: Urea kinetic modeling (Kt/V) is used to assess adequacy of hemodialysis (HD). However, serial Kt/V measurements may vary with time in the same patient, making the interpretation of the results difficult. The aim of the present study was to find the frequency and the causes that account for these fluctuations of Kt/V. Fifty-nine patients undergoing chronic HD were included in this prospective study. The results of monthly single pool Kt/V values were analyzed during a 6-month period. Duration of maintenance HD prior to the study was 4.49 +/- 3.6 (+/-SD) years. Any change of >0.2 from the previous 2-month average values was defined as abnormal. A total of 354 urea kinetic modeling sessions were recorded during 6 months in 59 patients. Of these, 38 (10.7%) met the criteria for abnormal value. Twenty-four measurements (6.7%) revealed lower while 14 (3.9%) demonstrated higher Kt/V values. Supervised sampling and conforming to the prescribed dialysis dose were applied for all abnormal measurements a week later. Among the group with lower Kt/V value, nine were due to noncompliance (shorter dialysis), four lower blood flow (Qb), four reversed needles, and one fistula thrombosis. Finally, in six cases no problem could be identified and a repeat measurement failed to document lower values. In the high-value group, nine cases were expected as there was an effort to increase dialysis dose prescription while five cases were due to false postdialysis sampling ("venous samples"). Overall, 29/354 (8.1%) measurements were in real disagreement with dialysis prescription. Lower-than-expected values are quite often due to reduced blood processing (shorter dialysis, lower Qb, and recirculation) and higher values due to inaccurate postdialysis sampling. Any possible pitfall in Kt/V measurements should be investigated before changing dialysis prescription in a stable HD patient.
Abstract: Metabolic acidosis correction is one of the goals of renal replacement therapy. Correction of acidosis in peritoneal dialysis (PD) may be affected by PD modalities such as automated PD (APD) or by new solutions containing a combination of bicarbonate and lactate as a buffer [bicarbonate continuous ambulatory PD (CAPD)]. The aim of the present study was to examine the acid-base status of our PD population and to compare the effects of APD, lactate CAPD, and bicarbonate CAPD on serum bicarbonate levels. We studied 35 stable patients undergoing APD (n = 15), lactate-buffered (35 mEq/L) CAPD (n = 14), and bicarbonate/lactate-buffered CAPD (n = 6) for 48.5 +/- 38.1 months. Most of our patients had serum bicarbonate levels in the normal range. In 3 patients (8%), HCO3 was below 22 mEq/L, and in 8 patients (22%; APD = 2, lactate CAPD = 2, bicarbonate CAPD = 4), HCO3 was above 28 mEq/L. We found no statistically significant correlations between HCO3 serum levels and PD prescription, peritoneal membrane characteristics, or intake of calcium carbonate and sevelamer hydrochloride. Patients on bicarbonate CAPD had higher HCO3 serum levels, but this difference disappeared when corrections for duration of dialysis, residual urine volume, and PD adequacy indices were applied. In the studied PD population, adequate correction of metabolic acidosis was achieved, as reflected in serum bicarbonate levels. We observed no difference in serum bicarbonate levels between APD and lactate CAPD patients. The new bicarbonate-buffered PD solutions are more biocompatible and can result in higher serum bicarbonate levels. However, a significant number of PD patients on bicarbonate-buffered solutions may become alkalotic. The clinical significance of these results needs further examination in prospective studies.
Abstract: The aim of this study was to verify if the degree of pre-HD acidosis and its correction post-HD is related to body fluid expansion during the interdialytic period. Twelve uremic patients without major problems, with stable hematocrit, with regular and similar HD-session characteristics, but widely varying amounts of body fluid expansion in the interdialytic period were included. Blood samples were collected from arterial line pre- and post-HD, anaerobically in heparinized syringes, for determination of HCO3-, pH and PaCO2 (radiometer Copenhagen ABL 300 Acid-Base Laboratory), in two similar HD-sessions for each patient (12 patients, 24 HD-sessions). The percentage (%) of body weight gain in the interdialytic period was also estimated. For each patient, the mean value of parameters studied in the two HD-sessions was used for the evaluation of findings. According to mean values (+/-SD) of HCO3-, pH and PaCO2 Pre-HD (18.26+/-1.99 mmol/L, 7.31+/-0.03, 36.27+/-2.5 mmHg respectively) and post-HD (26.37+/-1.7, 7.43+/-0.03, 38.43+/-2.10 respectively) patients are acidotic pre-HD and slightly alkalemic post-HD. Correlation between the percentage (%) of interdialytic body weight gain (IBWG) and the values of HCO3-, pH and PaCO2, Pre-HD (r=-0.814, p<0.001; r=-0.931, p<0.001; r=0, 100 NS; respectively) and post-HD (r=-0.958, p<0.001; r=-0.937, p<0.001; r=-0.504 NS; respectively) indicates a significant and negative relationship of IBWG% with HCO3- and pH pre- and post-HD, but not with PCO2. In conclusion, the negative relationship of IBWG% with HCO3- and pH pre- and post-HD indicates that the body fluid expansion during the interdialytic period contributes to a dilutional acidosis pre-HD, but not to a contraction alkalosis post-HD, by the elimination of fluid during the HD-session.
Abstract: The aim of this study was to determine the relationship between interdialytic weight gain and acid-base balance pre- and posthemodialysis in uremic patients undergoing hemodialysis with a high bicarbonate dialysate (39 mmol/L). To this end we studied 8 stable uremic patients on regular hemodialysis thrice weekly who had stable hematocrit values for at least 3 months, similar clinical characteristics including dry weight but widely varying interdialytic weight gain. Arterial line blood samples were collected anaerobically in heparinized syringes pre- and posthemodialysis in 4 consecutive hemodialysis sessions for the determination of pH, Paco2, and HCO3. Prehemodialysis values (mean +/- SD) were pH = 7.34 +/- 0.03, Paco2 = 36.43 +/- 1.4, and Hco3 = 20.1 +/- 1.55. Posthemodialysis values were pH= 7.47 +/- 0.02, Paco2 = 38.72 +/- 2.0, and HCO3 = 27.73 +/- 1.72. In other words, patients were moderately acidemic prior to and moderately alkalemic after the hemodialysis session. Of note, a significant negative correlation was revealed between the interdialytic weight gain and the values of prehemodialysis blood pH (r = -0.721, p < 0.001) and HCO3 (r = -0.836, p < 0.001) and posthemodialysis pH (r = -0.533, p < 0.001), Paco2 (r = -0.623, p < 0.001) and HCO3 (r = -0.815, p < 0.001), suggesting an important role of the interdialytic weight gain on acid-base equilibrium of uremic patients undergoing hemodialysis. Thus, patients with high interdialytic weight gains may require higher bicarbonate concentrations to achieve normal acid-base status whereas patients with low interdialyic weight gains may require lower bicarbonate concentrations to prevent alkalemia at the end of dialysis.
Abstract: A telemedicine system for home haemodialysis was designed using a systems approach and a feedback model to produce the hardware and software specifications. Preliminary clinical trials at four European locations involved 29 patients and 305 sessions of haemodialysis. The evaluation included an evaluability assessment and formative evaluation. Central to the methodology was the detailed specification of a stakeholder/evaluation criterion matrix. Preliminary results indicated that the telemedicine system was capable of satisfying the requirements of formative evaluation as a precursor to evaluating its overall worth.
Abstract: A rise in intracellular calcium concentration in erythrocytes has multiple effects on these cells. The purpose of this study was to determine the changes of calcium content in red blood cells (RBCs) and of echinocyte percentages in uremic patients during hemodialysis sessions. In 30 uremic patients under hemodialysis, the calcium content of RBCs and echinocyte percentages were determined in 3 blood samples collected at 0 min hemodialysis (prehemodialysis), 45 min hemodialysis, and 240 min hemodialysis (end hemodialysis) for a 4 h hemodialysis session. Calcium content of RBCs and echinocytes were also determined in 22 normal subjects (controls). The findings of the present study were that the mean values (+/-SD) of calcium content of RBCs in patients at 0 min hemodialysis, 45 min hemodialysis, and 240 min hemodialysis were 2.00 +/- 1.0, 2.66 +/- 0.87, and 1.62 +/- 0.66 microg/ml respectively and 0.65 +/- 0.07 microg/ml in controls. These values show that the calcium content of RBCs in uremic patients at 0 min hemodialysis, 45 min hemodialysis, and 240 hemodialysis was significantly higher than in controls (p < 0.0001), and that RBC calcium content at 45 min hemodialysis was significantly higher in comparison to that at 0 min hemodialysis (p < 0.001) and to that at 240 min hemodialysis (p < 0.0001), while that at 240 min hemodialysis was significantly lower than at 0 min hemodialysis (p < 0.05). The mean values (+/-SD) of echinocyte percentages in patients at 0 min hemodialysis, 45 min hemodialysis, and 240 hemodialysis were 11.93 +/- 6.18, 17.23 +/- 4.1, and 7.96 +/- 5.67% respectively, and in controls ranged from 0 to 1%. The values in uremic patients show a transient increase of echinocyte percentages at 45 min hemodialysis, which is significant in comparison to that at 0 min hemodialysis (p < 0.001) and to that at 240 min hemodialysis (p < 0.0001). Echinocyte percentages at 240 min hemodialysis were significantly lower to those at 0 min hemodialysis (p < 0.001). Correlation between calcium content of erythrocytes and echinocyte percentages shows a significantly positive relationship at 45 min hemodialysis (r = 0.368, p < 0.05) but no significant relationship at 0 min hemodialysis and 240 min hemodialysis. In conclusion, uremic patients under hemodialysis present with high calcium content in erythrocytes and abnormal erythrocytes like echinocytes. A rapid and transient increase of erythrocyte calcium is also accompanied by transient elevation of echinocytes in the first hour of hemodialysis (45 min hemodialysis), which returns after hemodialysis to lower than prehemodialysis levels.
Abstract: It has been reported recently that a number of cytokines, mainly tumor necrosis factor alpha (TNFalpha), interleukin (IL)-1beta, and IL-6, can alter lipid metabolism and produce hyperlipidemia. Studies in hemodialysis (HD) patients have demonstrated increased production of these cytokines during HD. In order to investigate any possible relationship between changes of cytokines and lipid concentrations during HD in the serum of 25 uremic patients on chronic HD using modified cellulose membranes, TNFalpha, IL-1beta, IL-6, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), lipoprotein a (Lp[a]), and total proteins were measured immediately before (pre-HD) and after HD (post-HD), in one session. The post-HD values were corrected according to the hemoconcentration based on the changes in serum total proteins. Serum TNFalpha and IL-1beta levels were significantly increased from 38.24 +/- 17.85 pg/ml and 2. 60 +/- 3.64 pg/ml pre-HD to 48.86 +/- 25.21 and 3.49 +/- 4.08 pg/ml post-HD, p < 0.001 and p < 0.05 respectively. Also Lp(a) levels presented a statistically significant increase post-HD and were almost doubled (pre-HD: 15.41 mg/dl, to post-HD: 27.39 mg/dl, p < 0. 05). Serum IL-6 as well as serum TC, TG, HDL-C, and LDL-C did not show any statistically significant alterations during HD. A significant positive correlation was detected between TNFalpha and Lp(a) values post-HD (r: 0.413, p: 0.04), but not between pre-HD values. No further relationship between serum cytokines and the other estimated lipid parameters was observed, either between pre- or post-HD values. Our results indicate that release of TNFalpha and IL-1beta during HD have no effect on serum lipids concentration, except on Lp(a). It seems that the acute rise of this lipoprotein during hemodialysis may be related with the TNFalpha overproduction.
Abstract: Home hemodialysis (HD) for the treatment of patients with end-stage renal disease (ESRD) was first put into practice about 30 years ago. In this paper we describe the application of telematics monitoring services (TMS) for supporting patients who need home or satellite HD (SHD). For the clinical trials two modified HD machines were located in the renal unit and a central control station (UNIX workstation with multimedia PC-terminal) was located in another room of the hospital. Bi-directional communication between modified HD machines and central control station was managed via ISDN (Integrated Services Digital Network) links. Using these HD-machines 150 HD sessions were performed in nine patients over a period of five months. This system enabled on-line remote supervision of the HD machine-related functions (air in the blood, leak of blood, low conductivity etc.) and the clinical condition of patients through measurement of blood pressure (BP), pulse rate, PO2 (pulse oxymetry) and electrocardiogram (ECG) from the central control station (CCS). The user checked the type of alarm/warning, its appearance on HD machines and multimedia terminal units (MTU), the action of the protective system and the appearance of consultative messages from CCS on the remote terminal unit RTU. According to the data collected, the disturbances of HD machine function were visible and audible in the CCS and the user messages were always observed on the RTU. No unusual dialysis-associated complications were observed, all data and alarms/warnings were transmitted correctly and patients had adequate HD treatment.
Abstract: In this study the ammonia concentration was determined in arterial and venous blood samples pre- and posthemodialysis (HD) in 18 uremic patients and in 18 health subjects (controls). The mean values (+/- SD) of ammonia in the arterial blood of uremic patients pre-HD were 98.32 +/- 26.55; post-HD, 63.18 +/- 17.09; and in control group patients, 72.37 +/- 10.09 micrograms/dl. In venous blood they were pre-HD, 71.70 +/- 20.68; post-HD, 58.05 +/- 16.73; and in control patients, 74.46 +/- 12.0 micrograms/dl. According to our findings, the ammonia concentration in the arterial blood of uremic patients pre-HD exceeds the normal limits and is significantly higher (p < 0.001) than that post-HD and that of control patients. The ammonia contents of venous blood pre- and post-HD ranges were within normal values, but the post-HD range was significantly lower than the pre-HD range (p < 0.05) and the control range (p < 0.01). Comparison between ammonia levels from arterial and venous blood showed significant and positive arteriovenous differences pre-HD (p < 0.001), which disappeared post-HD and were not observed in the control patients. In conclusion, uremic patients under HD present pre-HD high levels of ammonia in arterial blood with a significantly positive arteriovenous difference. In contrast, the post-HD ammonia levels in arterial and venous blood are decreased, and the arteriovenous difference is not significant.
Abstract: Graft artery stenosis is one of the main causes of hypertension in renal transplant recipients. We present a rare case of severe common iliac artery stenosis, proximal to the graft artery, that was the cause of accelerated hypertension and claudication in a male renal transplant recipient. After percutaneous balloon angioplasty combined with a Palmaz stent implantation, a dramatic improvement of hypertension and claudication was observed during a 10-month follow-up period.
Abstract: We measured blood ammonia in pre-angioplasty samples from the renal veins, aorta and inferior vena cava of 15 patients with hypertension due to unilateral renal artery stenosis confirmed by arteriography. Patients with renal insufficiency or small kidneys were excluded. Mean ammonia values were microgram/dl: vein of affected kidney, 106.00 +/- 12.75; vein of unaffected kidney, 75.65 +/- 23.10; aorta 61.04 +/- 15.00; vena cava, 62.44 +/- 19.65. The value for the affected kidney was significantly higher than the other three values (p < 0.001). Mean +/- SD DTPA uptake (%) was 42.8 +/- 2.21 in the affected kidney and 56.53 +/- 3.64 in the unaffected kidney. This difference did not correlate significantly with that of the ammonia concentrations tau = -0.292).
Abstract: In 18 uremic patients under regular hemodialysis (HD) with bicarbonate dialysate, the echinocytes and erythrocyte sedimentation rates (ESR) were determined in 4 blood samples collected from the arterial line at 0, 45, 120, and 240 min (end-HD) in one HD session by a bioincompatible dialyzer and in another by a biocompatible one. In the HD session by a bioincompatible dialyzer, the mean values (+/- SEM) of echinocytes (%) at 0, 45, 120, and 240 min were 8.89 +/- 1.15, 20.77 +/- 2.35, 7.39 +/- 1.1, 5.27 +/- 0.66 and of ESR (mm/h) were 65.00 +/- 6.26, 47.05 +/- 3.89, 66.72 +/- 6.00, 68.44 +/- 5.92, respectively. According to these findings, echinocytes show a transient significant increase at 45 min HD in comparison to those at 0 (p < 0.001), 120 (p < 0.001), and 240 (p < 0.001) min while ESR shows a transient significant decrease at 45 min HD compared with the rates at 0 (p < 0.05), 120 (p < 0.05) and 240 (p < 0.01) min. In the HD sessions with the biocompatible dialyzer, the mean values (+/- SEM) of echinocytes at the aforementioned 4 time points were 8.55 +/- 1.10, 17.05 +/- 2.40, 17.05 +/- 1.19, and 5.11 +/- 0.75%, and the ESR values were 60.89 +/- 6.08, 44.33 +/- 4.18, 62.94 +/- 6.55, and 65.61 +/- 6.13 mm/h, respectively. These values also show a transient significant increase of echinocytes at 45 min HD in comparison with those at 0 (p < 0.01), 120 (p < 0.01), and 240 (p < 0.001) min, with a parallel transient decrease of ESR at 45 min HD as compared to the ones at 0 (p < 0.05), 120 (p < 0.05), and 240 (p < 0.05) min. Although the echinocytosis at 45 min HD was more prominent in HD by the bioincompatible than by the biocompatible dialyzer, the comparison between these values indicates no significant difference in the echinocytes or the ESR. In conclusion, uremic patients receiving HD exhibit echinocytes, the percentage of which shows a transient increase at 45 min HD that returns to about baseline at 120 min HD. In parallel with the changes in echinocytes, the ESR shows an inverse change at 45 min HD which returns to baseline at 120 min HD.
Abstract: Isolated rabbit lungs were perfused with washed and resuspended human red blood cells (RBCs) in the presence of drugs known to change the shape and deformability of RBCs. With sodium salicylate (0.5-2 g/l), which causes echinocytosis and increases RBC deformability, lung diffusing capacity for O2 (DLO2) increased by 21%. When chlorpromazine, which induces stomatocytosis and stiffens RBCs, was given (50 mg/l), DLO2 decreased by 18% under chlorpromazine. Comparative experiments with hemoglobin solutions did not reveal any effect of those two drugs either on DLO2 or on pulmonary arterial pressure, which indicates that the effects of sodium salicylate and chlorpromazine were due to changes in RBC shape and deformability. It is concluded that RBC shape and deformability affect pulmonary artery pressure and oxygen diffusing capacity, which may have an influence on oxygen transfer to tissue and hence be of clinical relevance.
Abstract: Abnormal glucose metabolism in uremia may result from a complex interplay between decreased insulin secretion and insulin resistance. Recent studies report beneficial effect of biotin administration in glucose metabolism in diabetic animals and in a small number of patients with diabetes mellitus. The aim of the present study was to evaluate the response of oral glucose tolerance test (OGTT) to the i.v. administration of large doses of biotin in hemodialysis patients. Eleven hemodialysis patients aged 56.90 +/- 11.20 (32-76) years on regular hemodialysis thrice a week for 2.72 +/- 1.79 (1-7) years were studied. Fasting venous plasma glucose, glucosylated hemoglobin (%GH), and plasma glucose concentration 2 h after the administration of a 75-g glucose load were measured before, and 2 weeks and 2 months after administration of 50 mg of biotin i.v. postdialysis, and after a 2-month washout period. During the study, dialysis schedule and patients' medication, diet, and dry weight were kept unchanged. OGTT was abnormal in 4 patients before biotin administration and became normal in 3 patients (75%). Our results offer support to the findings of other studies about the beneficial effect of biotin in experimental or clinical diabetes mellitus, and argue for the involvement of biotin in glucose metabolism.
Abstract: Two dynamic tests (Gn-RH i.v. and clomiphene citrate-CC p.o.) were used to evaluate the hypothalamic-pituitary axis in hemodialysis patients and renal transplant recipients (recipients). In the Gn-RH test the gonadotropin secretion was maximally decelerated in hemodialysis patients while it was normal in recipients. During the CC test a decrease of gonadotropin secretion, chronically and quantitatively identical for both group, was found; while on the following test days an increase was noted, which was more accelerated in male recipients. In cases with uremia a strong negative feedback dominates at the pituitary level probably owing to testicular inhibin. The estrogenic feedback in uremia was intact, while the antiestrogenic feedback at the level of hypothalamus is partly impaired, owing to altered opioid metabolism.
Abstract: The safety and effectiveness of a low molecular weight heparin (LMWH) of 4500 +/- 1500 Daltons were evaluated in eight hemodialysis (HD) patients, in comparison with unfractionated heparin (UFH). In phase A of the study 3000 +/- 500 anti-factor Xa (AFXa) IU of LMWH were administered in bolus for the three consecutive HD sessions of a week. In phase B, 10000 +/- 2500 IU of UFH were administered to the same patients for the same time. Were observed no significant differences in hematocrit (Ht), platelets (Pt), fibronogen (FG) and prothrombin time (PT). Whole blood activated coagulation time (WBACT) was more prolonged with LMWH, 24 and 48 hours (start of next session) after administration (p < 0.05), and less prolonged at 5, 60, 120, 180, 240 min compared to UFH (p < 0.001). The activated partial thromboplastin time (APTT) and AFXa activity were more prolonged with UFH at 60 and 240 min (p < 0.001). The clinical effectiveness of the two preparations was similar as judged by thrombus formation and compression time. In conclusion, the present study found no real differences between LMWH and UFH, except for prolongation of WBACT 24 and 48 hours after the administration of LWMH. This probably indicates a cumulative effect of the LMWH and needs further investigation.
