Serum cystatin C levels in normal pregnancy.

AIM: The aim of this study was to determine the levels of cystatin C, creatinine and creatinine clearance in different trimesters of uncomplicated pregnancy in women with normal kidney function. SUBJECTS AND METHODS: A total of 109 pregnant women were included: group 1 - 38 women (average age 29.63 ± 4.3 y) in the first trimester, Group 2 - 32 women (average age 33.56 ± 5.95 y) in the second trimester and Group 3 - 39 pregnant women (average age 30.1 ± 6.95 y) in the third trimester. Serum cystatin C was determined by the PENIA method (Particle-Enhanced Nephelometric Immuno-Assay), using Behring tests (Behring Diagnostics GmbH, Marburg, Germany). Results were statistically analyzed using the ANOVA. RESULTS: A statistically significant increase in serum cystatin C level was found in the third trimester of pregnancy (0.69 ± 0.16 mg/l vs. 0.78 ± 0.26 mg/l vs. 1.21 ± 0.30 mg/l). CONCLUSION: It appears that cystatin C is not a reliable marker of kidney function in pregnancy and that its increase is connected with a combination of several factors, including endotheliasis, hormonal influence and glomerular filtration rate (GFR) alterations.

Hemodialysis headache.

AIM: The aim of this study was to evaluate and analyze the incidence and features of headaches in patients undergoing hemodialysis. MATERIAL AND METHODS: In this prospective study 318 patients, 119 women and 199 men, undergoing chronic HD in four hemodialysis centers in Serbia, were questioned about their problems with headaches using a questionary designed according to the diagnostic criteria of the International Headache Classification of Headache Disorders (ICHD) from 2004. Patients were distributed in two groups according to the presence of hemodialysis headaches (HDH). The groups were compared regarding sex, age, duration of HD, primary diseases that lead to ESRD, arterial systolic and diastolic blood pressure (BP) and serum levels of hemoglobin, urea nitrogen, creatinine, sodium, potassium, calcium, phosphates, albumin, glucose and calcium-phosphate product. We also analyzed features of HDH. The results were statistically compared. RESULTS: Patients with HDH had significantly lower serum glucose, but higher serum phosphates and albumin than patients without headaches. Furthermore, HDH patients had higher calcium phosphate product and systolic blood pressure than non-HDH patients. Out of 318 patients included in the study, 21 (6.6%) patients had HDH. According to our results, HDH appeared more frequently in men, during the 3rd hour of HD in more than a half of the patients and lasted less then 4 h in the majority of HDH patients. In the majority of patients HDH was bilateral, non-pulsating, without associated symptoms and it appeared mostly during HD. Personal history was negative for primary headaches in all patients with HDH. CONCLUSION: We believe that the results of our investigation of more than 300 HD patients pointed to some biochemical changes, possibly implicated by pathophysiology of HDH and disclose some specific HDH features that might contribute to a better understanding of this secondary headache disorder.

An experimental, non-uremic rabbit model of peritoneal dialysis.

Peritoneal dialysis (PD) is a well established method of depuration in uremic patients. Standard dialysis solutions currently in use are not biocompatible with the peritoneal membrane. Studying effects of dialysate on peritoneal membrane in humans is still a challenge. There is no consensus on the ideal experimental model so far. We, therefore, wanted to develop a new experimental non-uremic rabbit model of peritoneal dialysis, which would be practical, easy to conduct, not too costly, and convenient to investigate the long-term effect of dialysis fluids. The study was done on 17 healthy Chinchilla male and female rabbits, anesthetized with Thiopental in a dose of 0.5 mg/kg body mass. A catheter, specially made from Tro-soluset (Troge Medical GMBH, Hamburg, Germany) infusion system, was then surgically inserted and tunneled from animals' abdomen to their neck. The planned experimental procedure was 4 weeks of peritoneal dialysate instillation. The presented non-uremic rabbit model of peritoneal dialysis is relatively inexpensive, does not require sophisticated technology and was well tolerated by the animals. Complications such as peritonitis, dialysis fluid leakage, constipation and catheter obstruction were negligible. This model is reproducible and can be used to analyze the effects of different dialysis solutions on the rabbit peritoneal membrane.

Treatment of insulin resistance in uremia.

Insulin resistance is a characteristic feature of uremia. As long as the hyperinsulinemia adequate to overcome the insulin resistance, glucose tolerance remains normal. In patients destined to develop type 2 diabetes, the beta cell compensatory response declines, and relative, or absolute, insulin deficiency develops. At this point glucose intolerance and eventually frank type 2 diabetes occur. Insulin resistance and concomitant hyperinsulinemia are present irrespective of the type of renal disease. Several studies have confirmed that hemodialysis (HD) treatment significantly improves insulin resistance. Both CAPD and CCPD are shown to improve insulin resistance in uremic patients. Comparing the effect of PD and HD treatment, it was found that the CCPD group has significantly higher insulin sensitivity than the HD group with the CAPD group similar to HD. Treatment of calcium and phosphate disturbances, including vitamin D therapy, significantly reduces insulin resistance in uremia. Treatment with recombinant human erythropoietin (EPO) is an efficient way to increase hematocrit, to reverse cardiovascular problems and to improve insulin sensitivity. Angiotensin-converting enzyme inhibitors have been shown to improve insulin resistance, hyperinsulinemia and glucose intolerance in uremic patients. Thiazolidinediones (TZDs), the new insulin-sensitizing drugs, provide the proof that pharmacologic treatment of insulin resistance can be of enormous clinical benefit. The great potential of insulin resistance therapy illuminated by the TZDs will continue to catalyze research in this area directed toward the discovery of new insulin-sensitizing agents that work through other mechanisms.

Peritoneal dialysis adequacy and risk of death.

The debate on the relationship between small solute clearance and patient outcome on peritoneal dialysis has intensified in the past year with the publication or presentation of a number of important new studies. Previous studies had found a correlation between clearances and subsequent patient survival. However, this effect was all accounted for by residual renal clearance. The failure to detect an independent effect of peritoneal clearance on outcomes had been attributed to a lack of well-done studies with sufficient variation in peritoneal clearance to detect such an effect. New prospective and randomized studies suggest, however, that the relationship between peritoneal clearance and outcome is weak or absent within the usual dose ranges delivered in clinical practice. Existing clearance targets may need to be reviewed.

Quality of life of elderly patients undergoing continuous ambulatory peritoneal dialysis.

OBJECTIVE: The aim of the present study was to evaluate the impact of continuous ambulatory peritoneal dialysis (CAPD) on the lifestyle of elderly patients. PATIENTS AND METHODS: Aspects of health-related quality of life (OL) were studied in 48 patients (16 men, 32 women) in end-stage chronic renal failure (ESRF) undergoing CAPD at the Clinic of Nephrology, Clinical Centre of Serbia. The first group comprised 20 adult patients (8 men, 12 women; age range: 35-59 years). The second group consisted of 28 older adult patients (8 men, 20 women; age range: 65-75 years). Mean length of CAPD treatment was 5.2 years in the first group and 3.67 years in the second group. Fifteen QL variables were investigated: marital status, family relationships, working ability, sleep, tiredness, appetite, wound healing, hobby, sports, friendships, sexual activity, mood, travel, self management, and happiness. RESULTS: The results showed that, in the examined groups, marital status and relationships with family members weren't influenced at all by dialysis. In both groups, CAPD had a negative influence on ability to bear cold and to travel, but other life functions were not significantly affected. Elderly patients had a significantly worse appetite (p = 0.03, Fisher test) and mood (p = 0.045, Fisher test) than did younger adults. In other examined variables, no statistically significant differences were found between the groups. CONCLUSIONS: Lack of large, statistically significant differences between the groups suggests that CAPD has an equal influence on quality of life in younger and older adult patients.

Mesothelial paracrystalline inclusions in continuous ambulatory peritoneal dialysis patients.

OBJECTIVE: Uremia is known to be followed by changes in the serous membranes of pleura, pericardium, and peritoneum. During continuous ambulatory peritoneal dialysis (CAPD), the peritoneum is exposed to altered body conditions as well as to the influence of dialysate. The aim of the present study was to examine the ultrastructure of the mesothelial cells in CAPD patients, and to compare the findings with those from studies of the peritoneum in uremic controls. Paracrystalline intracytoplasmic inclusions in mesothelial cells were objects of special interest. METHODS: Biopsies of human parietal peritoneum were studied. These were taken from 12 uremic patients during catheter implantation before the start of CAPD, and from 7 CAPD patients during catheter removal for infection or malfunction. The samples were prepared in the standard way to be studied by transmission electron microscopy (TEM). RESULTS: Paracrystalline intracytoplasmic inclusions were seen in mesothelial cells only by TEM. They appear as filamentous structures at the outer part of the inclusions, and as pearl-like structures at the core of the inclusions. Sacculate dilatations of rough endoplasmic reticulum cisternae with partly destroyed membranes and only few ribosomes were also seen, with and without densely osmiophilic filaments within the cisternae. We have found paracrystalline intracytoplasmic inclusions in mesothelial cells from uremic and CAPD patients both. According to the literature, these changes are present in one third of biopsies from uremic patients. Until now, however, they have not been mentioned in CAPD patients.

[Changes in peritoneal mesothelial cells in patients on peritoneal dialysis]. / Promene celija mezotela peritoneuma kod bolesnika na peritonealnoj dijalizi.

INTRODUCTION: Some thirty years ago peritoneal dialysis (PD) became a respectable modality of renal replacement therapy. That is why peritoneal membrane attracted interest of investigators. Certain changes, known as uremic serositis, appear in morphology of serous membranes in end stage kidney disease (ESKD). The aim of our investigation was to examine the morphology of peritoneal lining cells in control group of healthy persons and morphology of peritoneal lining cells in patients on PD. MATERIAL AND METHODS: Peritoneal biopsies were taken in 10 healthy volunteers during the kidney donation and in 15 patients on PD during clinically indicated extirpation. Biopsy samples were prepared for standard routine HE staining and for plastic embedded fine sections studying. Sections were mounted in an ultramicrotome, stained with Toluidine blue (TB) and studied by light microscope (SM), while fine sections were mounted in an ultramicrotome and studied by transmission electron microscope (TEM). RESULTS: One layer mesothelium of the cuboidal or flattened lining cells were present over the lamina propria connective tissue. Mesothelial cells were overlapped like tiles on the roof. These cells were interconnected with different types of cell junctions (unpermeable, adhesion and communication junctions) positioned on lateral parts of the interdigitated cell membranes. A great number of microvilli were often present on the appical surface, as well as a kinocilia and lamellar bodies. Nuclei were euchromatic with well developed nucleoli. Many ribosomes, mitochondria, cisternae of rough endoplasmic reticulum (RER) and Golgi apparatus, lamellar bodies and lipid inclusions were present in the cytoplasm. Using TEM in analyzing fine sections of biopsies of patients on PD, characteristic ultrastructural changes including epithelial defects with only remaining parts of destroyed cells were established, as well as significantly greater number of rough endoplasmic reticulum (RER) cisternae and immature mesothelial cells in lamina propria indicating intensive regeneration of this epithelium. The cytoplasm of new mesothelial cells were of less electron density on TEM photomicrographs, whereas the nuclei of mesothelial cells in these patients were euchromatic with prominent nucleoli and numerous perichromatic granules and fibrogranular nuclear bodies, indicating cells of great activity. Cytoplasmic protrusions of different shape and content were often recognized on the apical surface of cells. Lamellar bodies were also present in this group of patients within the mesothelial cells, as well as between two mesothelial cells or on their apical surface. Mitochondria were picnotic in many of the mesothelial cells of peritoneum in this patient group. In these mesothelial cells intracytoplasmic paracrystaline inclusions were established. TEM photomicrographs showed basal lamina multiplication in this epithelium. CONCLUSION: Our findings comply with reports of other authors. It should be stressed that TEM examination detects characteristic ultrastructural changes in mesothelial lining cells of peritoneum in patients on PD, which could compromise the function of peritoneum as a membrane for dialysis.

[Ultrastructure of peritoneal mesothelial cells]. / Ultrastruktura mezotelnih celija peritoneuma.

The introduction of peritoneal dialysis (PD) as a respectable modality of renal replacement therapy some three decades ago, suddenly drew attention of many authors to peritoneal membrane as insufficiently investigated structure. In order to explain the pathological changes in peritoneum due to renal diseases, it became necessary to explore the normal peritoneal structure. The aim of this study was to examine the morphology of peritoneal lining cells in healthy persons. Biopsies of the peritoneum were performed on 20 volunteer kidney donors. Tissue samples were taken during renal transplantation. Special care was taken in getting appropriate samples without artificial damage because of the extreme fragility of the peritoneal tissue. The preparing procedure was standard for routine HE staining and for plastic embedded semifine and fine sections studies. Semifine sections were made on ultramicrotome, stained with Toluidin blue and studied by light microscope, while fine sections were made by ultramicrotome and studied by transmission electron microscope. One layer of cuboidal or flattened lining cells present over the lamina propria connective tissue presented mesothelium. The cells were overlapped like tiles on the roof. Lateral parts of their interdigitated membranes were interconnected with different types of cell junctions: unpermeable, adhesion and communication junctions; inhibiting intercellular transport. Cell surface was often covered with great number of microvilli and lamellar bodies. A single kinocilia was also often present on apical cell surface. Nuclei were euchromatic with well developed nucleoli. Cytoplasm was filled with a great number of ribosomes, mitochondria, cisterns of rough endoplasmatic reticulum and Golgi apparatus, lamellar bodies and lipid inclusions. Numerous pinocytic vesicles on all parts of the membrane as well as in the cytoplasm indicating active endocytosis, egsocytosis and transcytosys in the process of secretion and reabsorption of serous liquid in peritoneal cavity, were visible. Euchromatic nuclei with prominent nucleoli and numerous mitochondria indicate cells of great metabolic activity.

Ultrastructural changes of peritoneal lining cells in uremia.

Some thirty years ago, peritoneal dialysis (PD) became a respectable modality of renal replacement therapy. That is why peritoneal membrane attracted the interest of investigators. Uremia is followed by changes in the morphology of serous membranes (uremic serositis). Uremic effects on pleura and pericardia have been studied for a long time, but the peritoneum is affected as well. The aim of our study was to examine the morphology of the peritoneum in uremic patients before the start of PD and to compare the findings with those from examinations of peritoneum in healthy controls. We examined 12 uremic patients and 10 healthy controls (kidney donors). Biopsies were taken from parietal peritoneum. The samples were prepared in the standard way for study by transmission electron microscopy (TEM). Certain pathological changes--deformation of mesothelial cells, their detachment from the basement membrane, and unusual bulging of apical surface--were identified at the light microscopy level on semi-fine sections. Paracrystalline intracytoplasmic inclusions were seen in mesothelial cells only by TEM. We hypothesize that the inclusions were causing deformation of the mesothelial cells and detachment of those cells from the basement membrane. Sacculate dilatations of rough endoplasmic reticulum (RER) cisternae with partly destroyed membranes and few ribosomes were also seen, with and without densely osmiophilic filaments within cisternae. Although these changes are mentioned in the literature, the exact reason for their appearance remains unknown.

[Peritoneal dialysis in the aged]. / Peritoneumska dijaliza kod starih osoba.

INTRODUCTION: Patients older than 65 years represent the group of patients affected by end-stage renal failure characterized by the most rapid growth. The prevalent causes of end-stage renal disease (ESRD) in the elderly are diabetes mellitus and nephrosclerosis due to long-term arterial hypertension. There are a number of physiologic changes which occur with aging that might have an impact on the choice of renal replacement modality for an elderly patient: clinical or subclinical diminished cardiovascular reserve due to atherosclerosis or impaired baroreceptor function, slow deterioration of pulmonary function, impaired immunity, increased susceptibility to infection, metabolic disturbances, bone loss from osteoporosis, altered metabolism of protein and a variety of drugs, high rate of malnutrition, tendency to carbohydrate intolerance. MATERIAL AND METHODS: When choosing a dialysis regimen for an elderly patient, physiologic changes that occur with aging, specific medical conditions that are common in this period of life, medical and psychosocial advantages and disadvantages of the single mode need to be taken into consideration. DISCUSSION: Continuous ambulatory peritoneal dialysis (CAPD) is the predominant mode of therapy for elderly patients. Medical advantages of CAPD in elderly patients are easier control of hypertension and anemia, slower and sustained ultrafiltration, avoidance of cardiac arrhythmias, improvement of nutritional status, better correction of cognitive functions. Psychosocial benefits are home dialysis program, improvement of quality of life and avoidance of co-morbid diseases. There are contraindications to peritoneal dialysis which apply to elderly as well as to younger patients: inadequate peritoneal membrane function, hernias that cannot be repaired, inability to insert a chronic peritoneal access. Relative contraindications include recurrent pancreatitis, chronic back pain, recent aortic prosthesis placement, severe periferal vascular disease and recurrent diverticulitis. Further potential disadvantages of peritoneal dialysis in the elderly are depression and physical and intellectual incapability of self-performing dialysis in the absence of an adequate assistant. Besides, pain, malnutrition and in-hospitalization time associated with peritonitis may be less well tolerated in the elderly than in younger patients. Finally, anorexia, nausea and protein losses in dialysate may aggravate malnutrition. Food intake in the elderly is lower than in younger patients because of the financial situation, loneliness, habits, inertia, depression, bad teeth, impairment of sense of smell and taste, nausea, impeded moving, use of a variety of drugs and many other reasons. Renal failure aggravates malnutrition in the elderly, while peritoneal dialysis is characterized by significant protein losses in the dialysate. It is advisable to make an individual plan of nutrition for elderly patients on peritoneal dialysis in order to provide adequate intake of proteins, energy, vitamins and minerals. Survival rates are the same in patients on peritoneal dialysis and on hemodialysis, but the number of co-morbid conditions is higher in the first group. Age of course is a major death risk factor. Many complications of peritoneal dialysis occur no more frequently in the elderly than in younger patients. The rate of hospitalization is higher and its duration is longer in elderly patients, due to higher incidence of Staphyloccocus epidermidis peritonitis and vascular disease. Urea removal normalized to urea volume of distribution (Kt/Vurea) and weekly creatinine clearance are used as methods of assessing adequacy of peritoneal dialysis in the elderly. Creatinine production declines significantly in older patients and serum creatinine is a poor measure of level of renal function or dialysis adequacy. Assessment of quality of life is quite subjective. Only 15-30% of elderly patients on peritoneal dialysis relate their health worse t

[Effect of various methods of treatment in chronic renal insufficiency on the quality of life in patients]. / Uticaj razlicitih nacina lecenja bolesnika s hronicnom insuficijencijom bubrega na kvalitet zivota bolesnika.

Interest in measuring the quality of life (QL) in relation to health care has increased enormously in recent years. This is also true for end-stage renal failure where it is important not only to provide a better survival but also the quality of that survival. The aim of this study was to assess the relative influence of different kinds of treatment on end-stage renal disease after the patients' evaluation of their overall QL. We studied 167 patients receiving conservative treatment (45), haemodialysis (44), haemodialysis and erythropoieth (36), and continuous ambulatory peritoneal dialysis (42). The patients completed an original questionnaire consisting of 37 questions divided in five groups and generating 15 QL variables: personal data (name, gender, age, basic kidney disease); sociodemographic data influenced by the illness (family history, working ability, employment status); general health characteristics (fatigue, appetite, wound healing, sleep, resistance to cold); aspects of private life that are mostly influenced by the disease (social interaction, traveling, mood, sports, sexual life), and patients subjective assessment of their condition (self care and happiness). Patients on haemodialysis showed lower levels of QL than that on peritoneal dialysis related to fatigue (p < 0.01), working ability (p < 0.05), wound healing (p < 0.05), and appetite (p < 0.01) compared to the conservative treatment. Peritoneal dialysis had also a statistically significant positive influence on fatigue (p < 0.05) compared to conservative treatment. However, erythropoletin treatment showed better results with regard to traveling (p < 0.05), resistance to cold (p < 0.01), self care (p < 0.05) and mood (p < 0.05) compared to peritoneal dialysis, and working ability (p < 0.05), fatigue (p < 0.05) and mood (p < 0.05) compared to conservative treatment and haemodialysis.

[Functional evaluation in patients with kidney calculi]. / Funkciono ispitivanje bolesnika s kamenom u bubregu.

Nephrolithiasis is a common disorder and a significant problem because of incidence, recurrence and severe consequences. Stone disease is a surgical as well as a medical problem. Major progress has been made recently in understanding the pathophysiological disturbances responsible for stone formation as well as in the techniques of stone removal. The introduction of extracorporeal shock wave lithotripsy has considerably reduced the need for surgery. Improvements in methods of kidney stone removal have not diminished the need for the application of an effective prophylactic program. The internist should take a complete history of stone events (number, composition, location and outcome of stone event), family history of stones, dietary habits (focusing on the consumption of animal protein, salt and dairy products), medications and physical examination. Radiopaque stones should be documented by plane X-ray films. Ultrasonography should be used to image calculi that are nonopaque, and to easily distinguish them from masses such as tumour or blood clot. Computed tomography is also an excellent method for imaging nonopaque renal calculi but higher cost and radiation exposure are disadvantages [2]. Crystallographic analysis is the essential diagnostic procedure. If available, previous stones should also be examined. "In stone disease, everything is measurement. What the laboratory cannot tell you, you will not know; what it tells you in error, you will not correct by using your instincts, your medical experience, or your art [3]". Reliable diagnostic protocols are available for the identification of different causes of stones. The complexity of protocols depend on the severity of nephrolithiasis. Patients with a single stone episode undergo simple protocol, and extensive detailed protocol is used for patients with recurrent stone disease, or patients at increased risk. Simple protocol, besides the already mentioned history of stone events, radiographic investigation and crystallographic analysis, includes serum urea, creatinine, uric acid, sodium, calcium, phosphorus and protein levels, urinary pH and volume, urine samples for culture and urinary calcium, uric acid, oxalate and citrate. Extensive metabolic evaluation includes simple protocol, determination of serum levels of alkaline phosphatase, parathyroid hormone, thyroxin, magnesium. A 24-h collection of urine specimen is analysed for urea, creatinine, uric acid, calcium, phosphate, sodium, magnesium, oxalate and citrate. Extensive protocol includes specialized evaluation tests [5]. Urinary acidification test is important for detecting distal renal tubular acidosis. Two 24-h urine specimens are collected while the patient is on the regular diet. The patient is then placed on a restricted diet (400 mg of calcium and 100 mEq of sodium) for a week, and another 24-h urine sample is collected. After that fasting and calcium load tests are performed (Sheme 1). Fasting urinary calcium is used to detect renal calcium leak, and calciuric response to oral calcium load provides an indirect measure of intestinal calcium absorption. Diagnostic criteria for major forms of stone disease [8] are presented in Table 1. There are some still unsolved questions: does time after passage of stones or urological intervention influence the frequency of urine abnormalities that can be detected; are there differences in 24-h urine composition between weekdays and weekends: what is the prevalence of the most important urinary risk factors of recurrent idiopathic calcium nephrolithiasis: do male patients differ from females with respect to urinary risk factors or recurrent idiopathic calcium nephrolithiasis? [7].

[The effect of hemodialysis and continuous ambulatory peritoneal dialysis on renal anemia]. / Utcaj hemodijalize i kontinuisane ambulatorne peritoneumske dijalize na anemiju bubreznih bolesnika.

Anaemia is an almost invariable sign of chronic renal failure [1]. Although many factors have been implicated as causes of this anaemia, it seems probable that deficiency of erythropoietin is the main cause for most patients [2]. Institution of chronic dialysis can improve anaemia in end-stage kidney disease, continuous ambulatory peritoneal dialysis being reported as more successful [3]. The aim of this study was to investigate the influence of haemodialysis and continuous ambulatory peritoneal dialysis on anaemia during the first six months of treatment. We examined 21 persons (14 males and 7 females, aged from 18 to 78 years) on haemodialysis treatment and 13 persons (6 males and 7 females aged from 22 to 64 years) on continuous ambulatory peritoneal dialysis (Table 1). Standard procedures were used for measuring biochemical parameters. Urea and creatinine levels were high, almost incompatible with life, in all tested persons before dialysis treatment. During the first three months of both dialysis techniques urea and creatinine were significantly (p < 0.01) corrected, but remained above the normal ranges (Table 2). Patients on continuous ambulatory peritoneal dialysis have shown significantly (p < 0.01) lower urea and creatinine values compared to patients on haemodialysis (Graph 1). These data suggest better preservation of renal function and better control of the internal environment during continuous ambulatory peritoneal dialysis [6]. All tested patients were severely anaemic before the beginning of dialysis. During the first six months of haemodialysis erythrocyte count, haematocrit and haemoglobin levels were unchanged (Table 3). Transfusions and hepatitis episodes only temporary improved anaemia. Patients on continuous ambulatory peritoneal dialysis exhibited significant correction of anaemia already during the first three months of treatment (Graph 2). Though less significantly, haemoglobin values continued to rise even during the next three months. The reached haemoglobin levels were lower than normal, but significantly higher than values in patients on haemodialysis (p < 0.01), suggesting better control of anaemia during continuous ambulatory peritoneal dialysis. Transfusion requirement was irrelevant, and hepatitis was not noticed, so they cannot be held responsible for the improvement of anaemia. Greater iron consumption, illustrated by higher transferrin saturation, also confirmed increased erythopoitesis in patients undergoing continuous ambulatory peritoneal dialysis. They also had lower blood iron level than those on haemodialysis (who had) numerous blood transfusions. The improvement of anaemia during continuous ambulatory peritoneal dialysis may be the result of reduction in plasma volume [7] as well as an increase in red cell mass and a better clearance of middle molecules in comparison to patients on haemodialysis. The main cause is higher erythropoietin level [8]. All tested patients had low folic acid level. Patients who corrected anaemia showed fall in folat level. This was statistically remarkable during the first three months of continuous ambulatory peritoneal dialysis-from 3.64 ng/ml to 2.09 ng/ml. All these data suggest that both dialysis modalities are effective in the control of protein waste products level, but continuous ambulatory peritoneal dialysis has better influence on the improvement of anaemia that haemodialysis. This can be attributed to better removal of uremic toxins, improved protein metabolism, lower parathyroid hormone level and higher erythropoietin value due to peritoneal macrophage production.

[Radiographic changes in the sella turcica in female patients on chronic hemodialysis]. / Rendgenske promene cele turcike kod bolesnica na hronicnoh hemodijalizi.

The bone disease in chronic renal failure patients with secondary hyperparathyroidism is usually termed renal osteodystrophy. Radiographic methods have been applied in renal bone disease mainly to discover lesions on long bones, hands and fee. During the evaluation of hormonal disturbances of hemodialysed chronic renal failure female patients, roentgenograms of sella turcica were taken. Findings that were detected were most probably the consequences of renal osteodystrophy. Osteoporosis of clinoid processes posteriores and dorsum sellae and intrasellar calcifications were confirmed in 25 percent of investigated patients. Lateral view of the sellae turcica demonstrated a "double floor".These pathological findings in sella turcica region could be of practical importance because of well known anatomophysiological position of this sceletal structure.

[Hemostatic system parameters in patients with chronic renal insufficiency and arteriovenous fistula thrombosis]. / Osnovni parametri hemostatskog sistema kod bolesnika s hronicnom insuficijencijom bubrega i trombozama arterio-venske fistule.

Functional disturbances among different tissues and organic systems are associated with chronic renal failure. The most common problems following the disturbances in complex hemostatic changes in uremic patients are prolonged bleeding time ant the increased thrombosis tendency. As the patients vascular access is critical to the treatment of the chronic haemodialysis patient, we performed an investigation of causes of repeated vascular access thrombosis with purpose of detecting any consistent abnormality of the haemostatic system. Research has been conducted on a group of 29 patients (14 males and 15 females), age 21 to 61 (x = 45), on regular haemodialysis from 1 to 6 years (x = 2.2); 23 of them having one episode of thrombosis of vascular access, and 6 having two episodes. Partial thromboplastin time was among the normal ranges in all investigated subjects, three of them had low prothrombine time and thrombine time was prolonged in two cases. The high fibrinogen value was found in 19 patients. Mean value of platelet count was normal, though seven patients had thrombocytopenia. Absence of coagulum retraction was found in three patients. Assessment of blood coagulation in this study could not explain the development of repeated thrombotic events affecting arterio-vein fistula in chronic renal failure patients receiving haemodialysis. That points out the necessity to analyze functional status of natural coagulation inhibitors, fibrinolytic system and platelet function.

[Transport processes--ultrafiltration in peritoneal dialysis]. / Procesi transporta--ultrafiltracija na peritoneumskoj dijalizi.

In patients with terminal renal failure treated by peritoneal dialysis diffusion and ultrafiltration are used for removal of substances from the blood. Neofiltration is realized via the osmolar gradient, determined by different concentration of glucose and dialysis solutions. Osmotic water transport during peritoneal dialysis is limited. In the course of one exchange of two liters of the dialysate, exponential reduction of glucose levels in the peritoneal fluid ensues against time. Substance of low molecular weight, such as glucose, are resorbed from dialysate reducing the osmotic gradient between blood and dialysis fluid. Two successive phases in the course of exchange lasting for several hours are the main features of ultrafiltration during peritoneal dialysis. The first phase includes positive ultrafiltration, transport of water and soluble substances from the blood into the dialysate. Peritoneal volume increases gradually up to a certain maximum. Time needed to achieve that depends on the glucose concentration in the dialysate and time. The second phase starts when osmotic concentration of peritoneal solution becomes lower than osmotic concentration of the blood due to glucose resorption. It results in negative ultrafiltration, i.e. return of water and soluble substances from dialysis solution back into the blood: The paper reviews the production of concentration haemodialysis solutions at the Department of Pharmacy. Military Medical Academy, Belgrade. The first series of 3400 liters was produced during 1971. It is only 3% of the current production. Ever since, the extent of production and number of new products have increased annually. Today, 2500 lit of five types of solutions for hemodialysis are manufactured weekly at the Institute of Pharmacy. The quality of these solutions is secured by good manufacturing practise, quality control of substances and physico-chemical control of the produced solutions. The Institute of Pharmacy collaborates with the Clinic of Nephrology permanently improving and adjusting the production program.

[Renal tubular function in patients with nephrolithiasis]. / Ispitivanje funkcije tubula bubrega kod bolesnika s nefrolitijazom.

The aim of the study was to establish the frequency of tubular dysfunction in 59 patients with nephrolithiasis, of whom 52 had unilateral and 7 bilateral calculosis. Before the study urinary infection was cured in all patients. Renal function was normal in all subjects. Hypercalcaemia was present in 8 patients, and hypercalciuria in 17 subjects. Phosphate clearance (CPO4) was increased in 40 patients, and had the same number of patients, decreased tubular reabsorbtion of phosphate (TRP). In 31 patients increased CPO4 and decreased percent of TRP was present. Renal threshold phosphate concentration was decreased in 17 patients. High fraction excretion of sodium was observed in 37 patients, while urine sodium level was higher than normal only in 4 patients. Decreased ability of renal acidification of urine was found in 5 patients, and decreased renal concentration ability in 10 subjects. The most common finding in the observed patients was the phosphate excretion defect usually accompanied with defect of calcium excretion, and defect of urine acidification.

[Treatment of secondary hyperparathyroidism with vitamin D metabolites]. / Primena metabolita vitamina D u lecenju sekundarnog hiperparatireoidizma.

The aim of this double blind, comparative, randomized study was to eveluate the efficacy of treatment with 1-alpha-OHD3 plus 24,25(OH)2D3 in patients with secondary hyperparathyroidism.A group of 46 patients, 26 females and 20 males, aged 19-67, on chronic haemodialysis, was examined. During the first three months of therapy 0.25 mcg/day 1-alpha-OHD3 was given, and next three months 23 patients were treated with combination of 0.25 mcg/day 1-alpha-OHD3 plus 10 mcg/day 24,25(OH)2D3, and 20 patients recieved 1-alpha-OHD3 plus placebo. Plasma levels of calcium, phosphorus and alkaline phosphatease were measured every two weeks, but PTH and vitamin D metabolites before and eash three months of treatment. At the beginning of investigation all patients had high PTH levels, 25 had high levels of alkaline phosphatase and decreased or unmeasurable concentrations of vitamin D metabolites. Three months later 1,25(OH)2D3 was normal and at the end of the study 24,25(OH)2D3 reached normal value in the group with 24,25(OH)2D3 therapy. During the therapy changes of calcium and phosphorus levels were not significant in both groups, but they were statistically significant only in the group treated with both metabolites. Thus, the study is a good proof of efficacy and usefullnes of 1-alfa-OHD3 plus 24,25 (OH)2D3 regimen recommended.