Acquired Renal Cystic Disease and Tumor Markers in Chronic Hemodialysis Patients

Acquired renal cystic disease (ARCD) is a well documented complication of end-stage renal disease, and it has been related to the duration of dialysis therapy. The association of this condition with renal cell adenoma or carcinoma has already been established. There have also been studies on the concentration of some tumor markers in hemodialysis (HD) patients, clinically free from neoplastic disease, where it was concluded that some tumor markers could be elevated, despite the absence of malignant disease, suggesting their altered metabolism i.e. clearance by the hemodialysis membrane. We compared the pre-dialysis serum concentration of several tumor markers in three groups of chronic HD patients, all of whom had been on maintenance HD treatment for more than 5 years. Group 1 consisted of 16 patients without ARCD with a mean HD treatment duration of 97.06 ± 28.25 months. Group 2 consisted of 32 patients with a mean HD treatment of 105.62 ± 24.4 months, who had ARCD with less than 10 renal cysts detected by ultrasonography. Group 3 consisted of 14 patients with a mean HD duration of 109.92 ± 37.72 months, with ARCD and more than 10 renal cysts. Concentration of the following tumor markers was determined by EIA or ELISA methods: carcinoembryonic antigen (CEA), mucin-like carcinoma-associated antigen (MCA), neuron-specific enolase (NSE), carbohydrate antigen 19-9 (CA 19-9), prostatic specific antigen (PSA), carbohydrate antigen 125 (CA 125), alpha fetoprotein (AFP), cytokeratin 19-fragments 21-1 (CYFRA 21-1). The concentration of all the tumor markers was comparable in all three patient groups, with no statistically significant difference between groups. The mean concentrations of MCA, PSA, CA 125 and AFP were within the normal range. CEA and CYFRA 21-1 had mean values in the upper limit of their normal values, while NSE and CA 19-9 were increased by more than twofold in all three patient groups. We concluded that (i) tumor markers should be used with caution when diagnosing neoplastic diseases in chronic HD patients, because of their altered metabolism, and (ii) that in the follow up of ARCD with possible neoplastic alteration, imaging techniques remain dominant diagnostic tools.

Dialysis in Adults in Year 2000 in the Republic of Macedonia

1,019 adult patients with terminal renal failure were treated with dialysis (D) in the first part of the year 2000 in the Republic of Macedonia. 1,010 patients (99%) were treated with chronic intermittent (maintenance) hemodialysis (HD) while nine patients (1%) were on continuous ambulatory peritoneal dialysis (CAPD). For the children, a special peritoneal dialysis program was developed; 509 patients per million of the population (PMP) were on dialysis.

The Republic of Macedonia is, therefore, among those central and eastern European countries with a higher PMP number in the treatment of end-stage renal disease, following Croatia, the Czech Republic and Slovenia.

The patients were treated at 18 Centers in a network of HD Centers at a distance of 30–50 km. from their place of residence in order to facilitate their access to treatment and to work. All patients who have had symptoms indicating need for treatment with D were accepted for treatment. The government payed all the expenses of the treatment and the salaries of the staff. 56% were male and 44% were female patients. The youngest patient was aged 9 and the oldest was 82 years old. There has been an increase in the age of the patients on D as well as an increase in their number. In 1993 we had 727 patients being treated with D, and now we have 1,019 with a constant increase in the number of patients with ESRD and a need for D and renal transplantation. Mortality per year at the different Centers ranged from 8–19% in 1999 and the average is 12%.

Glomerulonephritis (GN) – both primary and secondary – is the main cause of renal failure (RF) in some Centers up to 45%. Tubulo-interstitial disease follows GN. ADPKD patients constitute 9.4% with a difference among the Centers of 3–29%, and diabetic nephropathy is found in 10%, 5–15% in different Centers. 11–61% of patients have an unknown etiology.

352 patients are on treatment with human recombinant erythropoietin (rhuEPO) – in some Centers up to 60%. The mode of application was subcutaneous and the initial dose is 20 U/kg body weight and the mean maintenance dose of EPO per patient weekly is 4,000 U.

The Cimino-Brescia arteriovenous fistula is being applied as a standard vascular access. The survival rate of our patients treated with maintenance HD at 5 years was 58%. CAPD and particularly renal transplantation are to be further developed as alternative methods in treating terminal renal failure.

Aminotransferase activity as a poor predictor of liver disease progression in dialysis patients with chronic hepatitis C

Lower aminotransferase activity in dialysis patients makes the assessment of the natural history of hepatitis C virus (HCV) infection difficult. The aim of the study was to determine the risk factors associated with the aminotransferase activity in dialysis patients with chronic hepatitis C. According to the serum levels of alanine aminotransferase (ALT) during the follow-up, the patients were divided in the two groups. The first group consisted of 34 chronically HCV infected patients with persistently normal levels of ALT. The second group included 46 chronically HCV infected patients with elevated levels of ALT. Genotype 1 was the dominant genotype in both groups (78 patients, 97.5%). Patients with the elevated ALT levels were characterized with a significantly shorter dialysis duration (p = 0.048) and a significantly shorter duration of HCV infection (p = 0.005) compared to the patients with persistently normal levels of ALT. The values of measured ultrasound parameters were not significantly different between the two groups. The univariate analysis identified a higher serum level of direct bilirubin (p = 0.044), shorter duration of dialysis (p=0.048), and shorter duration of HCV infection (p = 0.005) as potential predictors of elevated serum ALT levels in dialysis patients. After a stepwise logistic regression, none of the potential predictors was independently associated with the elevated ALT levels. Serum aminotransferase levels are poor predictors of liver disease progression in dialysis patients with chronic hepatitis C. Further studies should be conducted in order to identify non-invasive indicators of the disease progression in uremic patients with hepatitis C (Tab. 3, Ref. 22).

Doppler ultrasonography: a tool for nephrologists--single centre experience

Colour Doppler duplex ultrasonography (CDUS) has allowed noninvasive assessment of alterations of vascular perfusion showing general perfusion in colour. Since 1996, ultrasound examination by a duplex Doppler apparatus has been performed with an HDI 3000, ATL machine. We have retrospectively evaluated all patients (pts) with colour Doppler duplex examination for the last three years. Resistive indexes (RIs) are measured in each kidney using the existing software capabilities of the scanner. A total of 2581 CDUS examinations were performed over the past three years; in 2005 - 883 pts, in 2006 - 908 pts and in 2007 - 790 pts. Most of these examinations were on transplant pts. In 98 cases we examinated chronic rejection reactions, in 58 cases acute rejection and in 38 cases we postulated renal artery stenosis or thrombosis. We used CDUS to determine whether the RI can be used as a predictor in pts with Diabetic Nephropathy; in 108 cases we found an increased RI > 0.68. There is a positive correlation between the RI and the severity of arteriolosclerosis in the majority of pts, 331, where we found nephroarteriolosclerosis (RI > 0.64). In 52 cases renal artery stenosis was suspected (0.04 differences between RI on right and left renal artery). Acute renal failure was suspected in 53 cases. According to neoplasms, pathological, marked increased vascularization was noticed in 34 cases suspected for renal carcinoma, in 46 cases suspected of testicular tumours, 19 cases suspected of prostate neoplasm and in 32 cases suspected of tumours in other localizations. In combination with patient history, clinical and laboratory examination CDUS provides very useful information in accomplishing the diagnosis.

Role of mycophenolate mofetil in the treatment of lupus nephritis

Mycophenolate mofetil (MMF) is an immunosuppressive drug successfully used for the prevention of acute and chronic rejection of renal allografts, as well as in the therapy of glomerular disorders. We treated three groups of patients with lupus nephritis: the first group of patients had a high histologic activity index (AI), 13.4 +/- 2.34; the second group of patients had a high histologic chronicity index (CI), 6.0 +/- 0.7; and the third group consisted of only two patients, one with low AI (3.5) and another with low CI (1.5). The patients were treated for 2 years. MMF was initiated at a dose of 2 g/daily for the first 6 months and the dose was decreased to 1.5 g/daily for the further 18 months. Steroids, 0.4 mg/kg/day, were the concomitant therapy for the first 6 months, with slow tapering for the further 18 months. Patients with high AI presented significant decrease of serum creatinine after 2 years, 286 +/- 112.95 to 131.2 +/- 44.65 micromol/L. Two of the patients, with acute oligoanuria, were withdrawn from dialysis treatment. Significant improvement was also noted, 6.97 +/- 1.81 to 0.9 +/- 0.31 g/day. Patients with high CI had nonsignificant decrease of serum creatinine, 178.5 +/- 47.73 to 129.25 +/- 22.88 micromol/L, and significant improvement of proteinuria, 4.63 +/- 1.57 to 1.14 +/- 0.39 g/day. The patient with low AI showed recovery of renal function (serum creatinine from 196 to 72 micromol/L) and alleviation of proteinuria, 7.93 to 3.4 g/day. The patient with low CI did not respond to the therapy and renal function slowly worsened. MMF has emerged as a promising therapeutic approach for both the induction and maintenance phase in patients with lupus nephritis.

Progression of diabetic nephropathy: value of intrarenal resistive index (RI)

We used duplex Doppler analysis to determine whether the intrarenal RI can be used as a predictor in patients with diabetic nephropathy. Intrarenal resistive index (RI) values were obtained from intraparenchimal arteries of both kidneys, either the arcuate or interlobar arteries. Clinical parameters and renal function were also evaluated at baseline and after three and six months. Forty patients with diabetic nephropathy were divided into two groups based on their intrarenal RI values: group 1 had values of >or=70 and group 2 had values <70. Progression of renal function (delta creatinine clearance, delta CCr) was estimated by linear regression of the slope of decline of CCr plotted against time. At baseline, sixteen patients (40%) had an intrarenal RI value >or=70. Eight patients (50%) of them had a decline in renal function after six months. In comparison, among patients with intrarenal RI values <70 (n=24), only 2 had a decline in renal function. In multivariate regression analysis, proteinuria, lower baseline CCr and RI were independent predictors of declining renal function. An intrarenal RI value of >or=70 identifies diabetic patients at risk of progressive renal disease. The RI of interlobar arteries seems to be a dependable marker of intrarenal changes and can be used as a non-invasive, easily available parameter of the evolution in patients with advanced clinical diabetic nephropathy.

20 years after methylprednisolone/chlorambucil treatment in idiopathic membranous nephropathy stage II-III with nephrotic syndrome

There is now controlled evidence that a 6-month course with methylprednisolone and chlorambucil may favour remission of the nephrotic syndrome and may significantly improve the 10-year kidney survival in patients with idiopathic membranous nephropathy. We analyzed the outcome of 15 nephrotic patients (proteinuria 7.06 +/- 1.07 g/d), stage II-III membranous nephropathy, aged 37.93 +/- 2.32, 8 males and 7 females, with normal serum creatinine (62.8 +/- 2.34 micromol/l), followed > 10 years after the treatment. It consisted of 1g i.v. methylprednisolone for three consecutive days, followed by oral steroids 0.4 mg/kg/d and chlorambucil 0.2 mg/kg/d monthly, alternatively. 10 patients, age and sex matched, who refused any treatment of any reason, represented the control group. Complete remission was defined as protein loss of 0.2 g/d, partial 0.2-2 g/d with normal creatinine and renal dysfunction as increase in plasma creatinine. The follow-up period was between 10 and 20 years. Complete remission after the treatment was noted in 9/15, partial in 4/15, and 2/15 patients did not respond. 10-year survival rate of the whole group was 100%, 15-year - 86.7%, i.e. two patients with persistent nephrotic syndrome developed end-stage renal failure after 12 years. 13/15 patients (complete, partial remission) were followed > 15 years without development of end-stage renal failure. One patient (female, 32) developed idiopathic thrombocytopenia after 8 years. 3 patients (complete remission) were followed > 20 years, they are still without proteinuria. 10-year survival rate of untreated patients was 40%. It is concluded that in nephrotic patients with stage II-III membranous nephropathy steroids/chlorambucil therapy may be effective in favoring remission and in preserving renal function.

IgA nephropathy: 23 years of follow-up

IgA nephropathy (IgAN) is the most common primary glomerulonephritis. Some patients reach end-stage renal failure (ESRF), others experience an indolent course. We aimed the study to examine the association of risk factors with the progression to renal failure. Eighty patients diagnosed with IgAN by renal biopsy (RB) were studied. Baseline clinical and demographic data were reviewed. Severity of histological involvement was scored as H. S. Lee's grading system. The mean age of patients at biopsy was 36.65 +/- 8.83 years with predominance of men (male : female, 58 : 22). Patients were followed-up from 6 months to 23 years (276 months). An end-point was defined as the date when patient underwent their first haemodialysis or their last visit of follow-up. The differences in means between groups were compared by independent samples t-tests or one-way analysis of variance (ANOVA). Kaplan-Meier survival curves and Cox regression models were used to analyze the time course from renal biopsy to end points. The largest subclasses were grade I and II, with 31 patient each. Subclass III was observed in 12 patents. Subclass IV and V were found in 3 patients each. During the follow-up period, all patients with grade IV and V (after 6-48 months), five patients grade I (after 60-144 months), four patients grade II (after 48-84 months), and 7 patients from grade III (after 24-108 months) entered ESRD. Mean prioteinuria was 1.68 +/- 0.99 g/day. Macrohematuria had 32; microhematuria had 48 pts. The mean serum creatinine was 148.02 +/- 68.76 micromol/l. By multivariate analysis using the Cox regression model, grades, renal insufficiency and significant proteinuria were independent prognostic factors for progressive renal disease. At the end of follow-up, grades were significantly related to serum creatinine, proteinuria, hypertension and progressive renal disease. Renal biopsy in IgAN may be the most powerful predictor for renal outcome.

ANCA-GBM dot-blot test in diagnosis of patients with glomerulonephritis

Patients with rapidly progressive glomerulonephritis who are positive for anti-neutrophil cytoplasmic antibody (ANCA) or anti-glomerular basement membrane (GBM) antibodies may develop chronic renal failure leading to end-stage renal disease (ESRD) within days or weeks. The early serologic detection of auto-antibodies associated with ANCA and anti-GBM diseases will be helpful in preventing ESRD. We evaluated the combined ANCA-GBM dot-blot strip assay (Biomedical Diagnostics, Brugge, Belgium) in 30 consecutive patients with biopsy proven glomerulonephritis (GN). MPO- and PR3-ANCA were detected in 5 and 2 samples, respectively. Three samples were positive for both MPO- and PR3-ANCA (all 3 had focal segmental necrotizing GN). One patient was diagnosed as having Goodpastures' syndrome (the only anti-GBM positive result) and two had Wegener's granulomatosis (the two PR3-ANCA positive results). Two additional samples were equivocal: positive for MPO-ANCA and PR3-ANCA, respectively. Patients positive only for MPO-ANCA had only limited extrarenal organ manifestations. Anti-PR3 positive patients with necrotizing glomerulonephritis had a more dramatic deterioration of their renal function at diagnosis. Radiographically, these patients had nodular or pneumonia-like lesions. Acute respiratory failure necessitating mechanical ventilation was developed in one GBM positive patient. In conclusion, the ANCA-GBM dot-blot is a useful screening tool in situations where conventional ANCA testing is not readily available.

Therapeutic apheresis in the Republic of Macedonia - our five years experience (2000-2004)

Membrane plasma exchange (PE) is a mode of extracorporeal blood purification. Since 1985 membrane PE has been in regular use at the Department of Nephrology, Medical Faculty of Skopje, R.Macedonia. In this paper we report on five years (2000-2004) of single centre plasma exchange activity. We performed 540 PE treatments (108 PE/per year) on 99 patients. The M/F ratio was 40/48. The patients underwent a median of 5.45 procedures (range, 1-16). The treated patients were from different Departments. Protocols for PE depend on the disease and its severity. PE were performed 2-4 times weekly using Gambro PF 2000 N filters with an adaptation of the Gambro AK10 dialysis machine or with the Gambro Prizma machine (2 cases). Blood access was achieved through femoral vein. Substitution was made with fresh frozen plasma and/or with 20% human albumin combined with Ringer's solution. An average amount of 2150 ml plasmafiltrate per treatment (respectively 30 to 40 ml plasmafiltrate/kg body weight) was eliminated. Most therapeutic procedures were performed on patients from the Department of Neurology. 63.6% of all patients were referred for Myasthenia gravis and the Guillian Barre syndrome. The total number of procedures per year has remained fairly stable, corresponding to a median of 5.4 treatments/100 000 inhabitants. We observed hypocalcaemia in 8% of the patients, urticarial reactions in 7.3%, pruritic reactions in 12%, and hypotension/headache in 6.8%. No major procedural complications were seen.

Membranoproliferative glomerulonephritis complicating diabetic nephropathy

BACKGROUND

Renal diseases other than diabetic nephropathy can be found in diabetic patients who have undergone renal biopsy. Various forms of primary and secondary glomerular diseases were reported, but membranoproliferative glomerulonephritis was rare.

METHODS

Analyzing data at our Department for the past three years, we noted 18 patients with primary membranoproliferative glomerulonephritis and 4 associated with diabetic nephropathy.

RESULTS

Nodular glomerulosclerosis with diffuse membranoproliferative glomerulonephritis was registered in two patients and a diffuse form of diabetic nephropathy with a combination of segmental and diffuse changes characteristic of membranoproliferative glomerulonephritis in the other two patients.

CONCLUSIONS

Analyzing what can be common for these two diseases we can conclude that they are at least three disorders: 1. hyperperfusion injury, hallmark for the diabetic nephropathy, but also with the highest incidence in membranoproliferative glomerulonephritis than in the other glomerulonephritides; 2. mesangial matrix expansion, and; 3. thickening of all extracellular membranes.

Chronic allograft nephropathy (CAN) in early renal protocol biopsies: does treatment of borderline and subclinical acute rejections prevent development and progression of CAN?

Histological markers of chronic allograft nephropathy (CAN) in early protocol biopsies may ultimately result in deterioration of graft function. The aim of our study was to evaluate risk factors of early CAN histology and to determine whether treatment of borderline and subclinical acute rejections (BR/SAR) at 1-month posttransplant, prevents development and/or progression of CAN at 6-month biopsy. Thirty-five paired kidney allograft biopsies at 1 and 6 months after transplantation were blindly reviewed using Banff'97 criteria. The mean CAN score (sum of histological markers for chronicity) increased significantly at 6-month biopsy (1.83 +/- 1.46 vs 4.66 +/- 2.35; p < 0.01). No CAN was present in 27/70 biopsies (38.6%), 71.4% showed progression and 28.6% were with stable CAN at 6-month biopsy. When compared according to the progression, mean histological index (HI) score (sum of acute/chronic changes) in progressed CAN group (pCAN) increased significantly at 6-month biopsy (5.0 +/- 3.0 vs 9.5 +/- 2.8; p < 0.001). At 1-month biopsy, BR/SAR were found in 68% and 70%, in the pCAN and stable (sCAN) groups, respectively. The percentage of treated BR/SAR in sCAN group was significantly higher (57.1 vs 23.5%; p < 0.05), and the score of acute histological lesions lower (1.08 +/- 0.95 vs 0.35 +/- 0.66; p < 0.01) at 6-month biopsy. In conclusion, 1-month protocol biopsy may be valuable to uncover BR/SAR and the presence of early CAN in stable renal allografts. Progression of CAN at 6-month biopsy in our study was found to be associated with a greater number of untreated BR/SAR at 1-month biopsy. This observation may have important implications in the design of clinical trials aimed to prevent the progression of CAN.

Recurrent glomerulonephritis in living kidney transplantation

Glomerulonephritis (GN) is one of the most frequent causes of end-stage renal disease. Recurrent GN can occur very early after transplantation in up to 20% of renal-allograft recipients and should be considered with late graft dysfunction in 2-5%. Importantly, diagnosis of a clinically silent recurrence of the disease will pass undetected unless transplant centers have a policy of protocol biopsies. In addition, the classification of the type of recurrent GN should be done with data on electron microscopy and immunofluorescence, in order to promote prompt treatment and a strategy for long-term graft survival. The aim of our paper was to present a few typical cases of recurrent GN, showing the actuality of the problem in living related kidney transplant recipients and to ascertain the importance of precise and timely diagnosis by protocol biopsy. Recurrent focal segmental glomerular sclerosis (FSGS) in childhood is associated with the highest number of graft loss. The treatment of recurrent FSGN is difficult, so prophylactic plasmapheresis prior to transplantation appeared to be more effective in preventing recurrence than plasmapheresis after transplantation, especially in population of children. Mesangio proliferative GN type II is the second most frequent recurrent GN, followed by type I. Here, it is of paramount importance to classify the type of the disease. The family of the patient at risk for recurrent GN, a candidate for living related kidney transplantation, should be informed for the expected outcome and their voluntary decision whether to proceed with transplantation should be awaited.

The evolution of untreated borderline and subclinical rejections at first month kidney allograft biopsy in comparison with histological changes at 6 months protocol biopsies

Our study sought to identify the possible implications of histological findings of borderline and subclinical rejections as well as histological markers of chronic allograft nephropathy (CAN) in protocol biopsies at 1 and 6 months after living-related kidney transplantation. Twenty-eight paired allograft biopsies were blindly reviewed using Banff '97 criteria, among which only 10.7% (6/56) showed no histopathological lesions. BR was found in 9/28 (32.1%) and 6/28 (21.4%), and SR in 3/28 (10.7%) and 10/28 (35.7%) of the patients, in the 1 and 6 month biopsies, respectively. The mean CAN score (sum of histological markers for chronicity) increased significantly at 6 months biopsy, 1.57 +/- 1.36 vs. 4.36 +/- 2.32 (p < 0.01). When compared according to chronicity index (CI < 5 >), the high CI group had a mean CAN score of 2.36 +/- 1.15 at 1 month, which increased to 5.14 +/- 1.99 at 6 months biopsy (188.9%). The proportion of these changes in low CI group were also increased from 0.79 +/- 1.12 to 3.57 +/- 2.38 (451.9%). In conclusion, a protocol 1 month biopsy may uncover a high prevalence of BR or SR in stable allografts. The presence of an untreated BR or SR in biopsies with low chronicity index showed greater susceptibility to histological deterioration on the 6 month biopsy, associated with rapid impairment of graft function and chronic allograft nephropathy.

Protocol Biopsies in Kidney Transplant Recipients: Histologic Findings as Prognostic Markers for Graft Function and Outcome

The aim of the present study was to identify subclinical and borderline rejections as well as histological markers of chronic allograft nephropathy (CAN) among protocol biopsies performed at 1 and 6 months after living related kidney transplantation to assess their possible implications for graft function. Twenty paired allograft biopsies performed at 1 and 6 months were reviewed according to the Banff scoring scheme. The mean ages of donors and recipients were 59.6 +/- 13.8 and 34.4 +/- 8.7 years, respectively. Among all biopsies only 10% (4/40) showed no histopathological lesions. At the first month borderline rejection was shown in 35% and subclinical rejection in 10% of patients. At 6 months the proportion of findings was even higher, namely, 40% and 30%, respectively. When divided according to donor age, donors above 55 years showed a mean CAN score of 2.33 +/- 1.56 which increased to 5.0 +/- 2.26 on the 6 month biopsy (214.3%). Unexpectedly, the proportion of these changes in the younger donor group also increased by 173.3%, which might have been explained by the greater number of borderline and subclinical rejections in the younger donor group at the 1 month biopsy. In conclusion, 1 month biopsy may be valuable to determine borderline and subclinical rejection and to prognosticate the outcome of renal allograft function. Our findings suggest a greater susceptibility of histological deterioration among the older donor population. However, the presence of an untreated rejection in the younger donor pool leads to a rapid impairment of the graft function accelerating the process of chronic allograft nephropathy.

Acute renal failure with severe tubulointerstitial changes in a patient with minimal change nephrotic syndrome treated with enalapril

A 35-year-old nephrotic man developed acute renal failure with serum creatinine to 1543 micromol/l after a month of therapy with enalapril. Renal biopsy demonstrated minimal glomerular changes with fusion of podocytes, tubular necrosis with regeneration of tubular epithelial cells, interstitial edema with focal interstitial fibrosis, and interstitial infiltration with neutrophils, eosinophils, plasma cells and mononuclear cells. Three hemodialyses were performed in the patient during the oliguric phase of the disease. Renal function was restored after withdrawal of enalapril and initiation of steroid therapy. Steroids also contributed to the improvement of the nephrotic syndrome and proteinuria decreased from maximal ranges of 27 g/l to 2.2 g/l after six months of the follow-up. Similar cases were previously described associated with captopril treatment, but not with enalapril.

Acquired renal cystic disease and tumor markers in chronic hemodialysis patients

Acquired renal cystic disease (ARCD) is a well documented complication of end-stage renal disease, and it has been related to the duration of dialysis therapy. The association of this condition with renal cell adenoma or carcinoma has already been established. There have also been studies on the concentration of some tumor markers in hemodialysis (HD) patients, clinically free from neoplastic disease, where it was concluded that some tumor markers could be elevated, despite the absence of malignant disease, suggesting their altered metabolism i.e. clearance by the hemodialysis membrane. We compared the pre-dialysis serum concentration of several tumor markers in three groups of chronic HD patients, all of whom had been on maintenance HD treatment for more than 5 years. Group 1 consisted of 16 patients without ARCD with a mean HD treatment duration of 97.06 +/- 28.25 months. Group 2 consisted of 32 patients with a mean HD treatment of 105.62 +/- 24.4 months, who had ARCD with less than 10 renal cysts detected by ultrasonography. Group 3 consisted of 14 patients with a mean HD duration of 109.92 +/- 37.72 months, with ARCD and more than 10 renal cysts. Concentration of the following tumor markers was determined by EIA or ELISA methods: carcinoembryonic antigen (CEA), mucin-like carcinoma-associated antigen (MCA), neuron-specific enolase (NSE), carbohydrate antigen 19-9 (CA 19-9), prostatic specific antigen (PSA), carbohydrate antigen 125 (CA 125), alpha fetoprotein (AFP), cytokeratin 19-fragments 21-1 (CYFRA 21-1). The concentration of all the tumor markers was comparable in all three patient groups, with no statistically significant difference between groups. The mean concentrations of MCA, PSA, CA 125 and AFP were within the normal range. CEA and CYFRA 21-1 had mean values in the upper limit of their normal values, while NSE and CA 19-9 were increased by more than twofold in all three patient groups. We concluded that (i) tumor markers should be used with caution when diagnosing neoplastic diseases in chronic HD patients, because of their altered metabolism, and (ii) that in the follow up of ARCD with possible neoplastic alteration, imaging techniques remain dominant diagnostic tools.

Hantaan virus infection with acute renal failure

We report on 10 patients with acute renal involvement in Hantaan virus infection observed at the Department of Nephrology, Faculty of Medicine, Skopje, Republic of Macedonia, during a period of 3 years (October 1987-July 1990). Eight patients were male and 2 were female, aged 37.5 +/- 4.8 years. The diagnosis of Hantaan virus infection was proven by an indirect immunofluorescent and ELISA test with a significant increase of the titer after a week to ranges from 1:512 to 1:2,048. Percutaneous renal biopsy was performed in 3 cases using standard procedures for optical and immunofluorescent microscopy. Fever, weakness, headache, conjunctival injection, hematuria, and lumbar pain were clinical features all patients had in common. Complete anuria was noted in 7 out of 10 and oliguria in the other 3 of the 10 cases with serum levels of creatinine 967 +/- 152.6 mumol/L. Other following laboratory findings were leukocytosis in 10 out of 10 patients, with neutrophylia, and reduction of serum sodium and potassium in 8 out of 10, and a decrease in serum complement C3 in 3 out of 10 patients. Percutaneous renal biopsy confirmed interstitionephritis in 2 out of 3 biopsied patients and acute diffuse proliferative glomerulonephritis in the third. Interstitial mononuclear infiltration with dominant T cells proven with monoclonal antisera (direct immunoperoxidase method) was present in all 3 cases. The outcome of the disease was good in 8 of the 10 patients with a development of polyuric phase and complete recovery of renal function later. One patient with interstitial lesions on biopsy developed chronic renal failure, and the other with a concomitant brucellosis died during the polyuric phase of the disease.