Olga Balafa

Influence of the Type of Membrane and Heparin on Serum Lipid Parameters during a Dialysis Session: A Pilot Study

Background/Aim: The type of heparin and membrane used might influence the lipids in patients on hemodialysis (HD). However, there are limited and debatable data concerning the lipid changes during an HD session. The aim of our study was to examine the changes in serum lipid parameters during the HD session in relation to the heparin and dialysis membrane used. Methods: Ten patients on HD 3 times/week participated in the study. The study was performed in three phases (A, B, C), each of 1 week’s duration. The types of membranes used were Hemophan (phase A), ethylene vinyl alcohol (phase B) and polyacrylonitrile (phase C), respectively, in a random order. During the midweek session of each phase we used classic heparin, while during the session at the end of the week low molecular weight heparin was administered. Serum total cholesterol, triglycerides, HDL cholesterol, Lp(a), albumin and total proteins were measured before and 5 min after the HD and hourly during the HD session. Results: In all phases, we found a progressive increase in all lipid parameters during the HD session, except Lp(a). This increase, however, was possibly due to hemoconcentration. Conclusions: This pilot study showed that (1) the type of heparin and membrane used does not seem to affect the serum lipid profile during a single HD procedure, and (2) the changes observed in serum lipid parameters are mainly due to hemoconcentration.

Optimal Medical Management in Patients with Renovascular Hypertension

Renovascular hypertension refers to the rise of arterial pressure due to reduced perfusion of the kidney caused by the stenotic renal artery/ies. The most common cause of stenotic renal artery is atherosclerosis. Atherosclerotic renal stenosis is usually part of a systemic syndrome that involves hypertension, intrinsic renal damage, and cardiovascular morbidity. So far, large trials have not proven the superiority of interventional therapies to medical management. As a result, renal artery stenosis should be treated mainly as a coronary artery disease equivalent focusing on rigorous management of hypertension, hyperglycemia, and hyperlipidemia. Antihypertensive treatment should include renin-angiotensin system blockade medication in most cases, while HMG-CoA reductase inhibitors (statins) can be used even in chronic kidney disease with safety. Lifestyle modifications, such as cessation of smoking, and antiplatelet therapy have reduced the risk of cardiovascular events in high-risk patients.

Posterior reversible encephalopathy syndrome: a noteworthy syndrome in end-stage renal disease patients.

Background: Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiologic entity characterized by headache, visual disturbances, seizures, and the presence of edema on MRI scan, predominantly in the posterior white matter. Regarding end-stage renal disease (ESRD) and PRES, only a few cases of children on peritoneal dialysis (PD) and adults on hemodialysis have been described in the literature. Cases: We report 4 cases of adult patients on PD who presented with PRES, all of which were due to hypertension and inadequate management of fluid balance. The patients expressed typical PRES symptoms such as headache, visual disorders, and tonic/clonic seizures. The patients recovered completely and the MRI lesions disappeared after strict control of volume status. Conclusion: Nephrologists should be aware of the syndrome, especially when they manage hypertensive ESRD patients not compliant with the fluid and diet restrictions. MRI scan is the only diagnostic tool for defining the syndrome. Early diagnosis is important, since complete remission is achieved after appropriate treatment.

Urine of Patients with Nephrotic Syndrome Contains the Plasma Type of PAF-Acetylhydrolase Associated with Lipoproteins

Background: Platelet-activating factor (PAF) is a proinflammatory phospholipid mediator involved in the pathogenesis of glomerulonephritis (GN). In plasma, PAF is hydrolyzed and inactivated by PAF-acetylhydrolase (PAF-AH), an enzyme associated with lipoproteins, mainly with the low-density lipoprotein. PAF-AH activity has been found in urine of patients with primary GN, however the source and type of urinary PAF-AH remain unknown. We characterized the type of PAF-AH excreted in the urine of patients with primary GN and studied the possible relationship of this enzyme with the lipiduria and proteinuria observed in these patients. Methods: Eighteen patients with primary GN (8 with nephrotic syndrome (NS) and 10 with non-nephrotic range proteinuria (NNRP)) and 20 normolipidemic age- and sex-matched controls participated in the study. PAF-AH activity in plasma, in urine and in individual lipoprotein particles was determined by the trichloroacetic acid precipitation procedure, whereas the PAF-AH protein was detected by Western blotting analysis. Plasma and urine lipoproteins were fractionated by gradient ultracentrifugation and characterized by Western blotting analysis. Results: Plasma PAF-AH activity was higher in NS patients compared with NNRP patients and controls, whereas the enzyme activity associated with high-density lipoprotein was significantly lower in both patient groups compared with controls. PAF-AH was detected only in the urine of NS patients. It was the plasma type of PAF-AH and was associated with lipoprotein particles. Enzyme activity was also positively correlated with urine cholesterol levels. Conclusion: Urine of NS patients contains the plasma type of PAF-AH, which is related to the extent of lipiduria and is associated with urine lipoproteins.

Acute Effect of Heparin on Lipid Parameters in Patients on Renal Replacement Therapy

Dialyzer membrane and the type of heparin used can influence lipid parameters. However, there are limited and debatable data concerning lipid alterations during a single hemodialysis session. Moreover, the role of hemoconcentration after every hemodialysis session confuses the real effect of the heparin on lipid profile. We investigated the acute effect of heparin administration on lipids in hemodialysis patients, but on an off-hemodialysis day in order to eliminate any effect of ultrafiltration. We studied six patients on hemodialysis, six patients on peritoneal dialysis, and six healthy persons. The study was performed in two phases (1 week apart). In phase A, we used unfractionated heparin (5000 IU, intravenous), whereas in phase B, low-molecular-weight heparin (3500 anti-FXa, intravenous) was used. Total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and Lp(a) were estimated before and 1, 2, 3, and 4 hours after heparin administration. We observed a reduction only in triglycerides (at the first, second, and third hour) in both phases in all groups. The other lipid parameters were not affected. In conclusion, acute administration of both types of heparin seems to affect only triglyceride levels in patients on renal replacement therapy.

An Unusual Case of Hemoperitoneum: Spontaneous Rectus Sheath Hematoma

with kinking, which might have caused damage to the catheter at the start, with the damage being worsened during each dialysate exchange and the repeated migration with kinking. The eventual result was full fracture of catheter (Figure 3). We conclude that Tenckhoff catheter fracture is a rare cause of catheter malfunction, but that catheter fracture should be considered in the differential diagnosis of catheter malfunction.

Crescentic glomerulonephritis and membranous nephropathy: a rare coexistence

BackgroundThe coexistence of crescents and membranous glomerulonephritis (MGN) is a special characteristic in lupus nephritis. In the absence of the characteristic histological features of lupus nephritis, MGN with crescents should raise the possibility of two other histopathological entities: anti-GBM disease and necrotizing and crescentic glomerulonephritis. The last one includes patients with positive ANCA serology or not.Results and conclusionsHere, we describe a case of a male patient who presented with extrarenal vasculitis symptoms, acute renal failure, hematuria and nephrotic-range proteinuria. ANCA serology was positive, and the biopsy revealed crescentic vasculitis plus membranous nephropathy. Reviewing the whole literature about similar histological cases, we included 38 cases with ANCA-positive serology and 30 ones with no ANCA in serum. It seems that in the first category vasculitis symptoms predominate, while in the second one these symptoms are absent. Their histological features have no major differences. In any case, the clinical course of these patients is serious, and in most cases, immunosuppression is essential in order to avoid end-stage renal disease.

An unusual case of acute kidney injury - idiopathic granulomatous tubulointerstitial nephritis.

We present a case which emphasizes the importance of performing a kidney biopsy in each case of acute kidney injury (AKI) of unknown etiology. The unexpected histological diagnosis of granulomatous interstitial nephritis (GIN) is a rare cause of AKI. The main causes of GIN include drugs (NSAIDs, antibiotics), sarcoidosis, and infections (mycobacterial and fungal). In our case, a 68-year-old woman was admitted with AKI, absence of symptoms and unremarkable history, apart from coronary heart disease. Renal biopsy was performed, since history as well as clinical and laboratory data could not define a cause of AKI. A more meticulous clinical and laboratory investigation followed the histological diagnosis in order to rule out sarcoidosis, vasculitis or any other known causes of GIN. Finally the diagnosis was characterized as AKI due to idiopathic GIN. The patient responded well to corticosteroids.

Prevalence and control of hypertension by 48-h ambulatory blood pressure monitoring in haemodialysis patients: a study by the European Cardiovascular and Renal Medicine (EURECA-m) working group of the ERA-EDTA

Background Population-specific consensus documents recommend that the diagnosis of hypertension in haemodialysis patients be based on 48-h ambulatory blood pressure (ABP) monitoring. However, until now there is just one study in the USA on the prevalence of hypertension in haemodialysis patients by 44-h recordings. Since there is a knowledge gap on the problem in European countries, we reassessed the problem in the European Cardiovascular and Renal Medicine working group Registry of the European Renal Association-European Dialysis and Transplant Association. Methods A total of 396 haemodialysis patients underwent 48-h ABP monitoring during a regular haemodialysis session and the subsequent interdialytic interval. Hypertension was defined as (i) pre-haemodialysis blood pressure (BP) ≥140/90 mmHg or use of antihypertensive agents and (ii) ABP ≥130/80 mmHg or use of antihypertensive agents. Results The prevalence of hypertension by 48-h ABP monitoring was very high (84.3%) and close to that by pre-haemodialysis BP (89.4%) but the agreement of the two techniques was not of the same magnitude (κ statistics = 0.648; P <0.001). In all, 290 participants were receiving antihypertensive treatment. In all, 9.1% of haemodialysis patients were categorized as normotensives, 12.6% had controlled hypertension confirmed by the two BP techniques, while 46.0% had uncontrolled hypertension with both techniques. The prevalence of white coat hypertension was 18.2% and that of masked hypertension 14.1%. Of note, hypertension was confined only to night-time in 22.2% of patients while just 1% of patients had only daytime hypertension. Pre-dialysis BP ≥140/90 mmHg had 76% sensitivity and 54% specificity for the diagnosis of BP ≥130/80 mmHg by 48-h ABP monitoring. Conclusions The prevalence of hypertension in haemodialysis patients assessed by 48-h ABP monitoring is very high. Pre-haemodialysis BP poorly reflects the 48 h-ABP burden. About a third of the haemodialysis population has white coat or masked hypertension. These findings add weight to consensus documents supporting the use of ABP monitoring for proper hypertension diagnosis and treatment in this population.

Estimation of Residual Peritoneal Volume Using Technetium-99m Sulfur Colloid Scintigraphy.

Residual peritoneal volume (RPV) may contribute in the development of ultrafiltration failure in patients with normal transcapillary ultrafiltration. The aim of this study was to estimate the RPV using intraperitoneal technetium-99m Sulfur Colloid (99mTc). Twenty patients on peritoneal dialysis were studied. RPV was estimated by: 1) intraperitoneal instillation of 99mTc (RPV-99mTc) and 2) classic Twardowski calculations using endogenous solutes, such as urea (RPV-u), creatinine (RPV-cr), and albumin (RPV-alb). Each method’s reproducibility was assessed in a subgroup of patients in two consecutive measurements 48 h apart. Both methods displayed reproducibility (r = 0.93, p = 0.001 for RPV99mTc and r = 0.90, p = 0.001 for RPV-alb) between days 1 and 2, respectively. We found a statistically significant difference between RPV-99mTc and RPV-cr measurements (347.3 ± 116.7 vs. 450.0 ± 67.8 ml; p =0.001) and RPV-u (515.5 ± 49.4 ml; p < 0.001), but not with RPV-alb (400.1 ± 88.2 ml; p = 0.308). A good correlation was observed only between RPV-99mTc and RPV-alb (p < 0.001). The 99mTc method can estimate the RPV as efficiently as the high molecular weight endogenous solute measurement method. It can also provide an imaging estimate of the intraperitoneal distribution of RPV.