Epidemiology of PRA in Pre Transplant Renal Recipients and its Relation to Different Factors

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1 Med. J. Cairo Univ., Vol. 82, No. 1, March: , Eidemiology of in Pre Translant Renal Reciients and its Relation to Different Factors USAMA MOHAMADY, M.D.*; IHAB ABDELRAHMAN, M.D.*; KARIM M. SOLIMAN, M.Sc.*; DAWLAT A. BELAL, M.D.* and MERVAT ELANSARY, M.D.** The Deartments of Internal Medicine, Division of Nehrology* and Clinical Pathology**, Faculty of Medicine, Cairo University Abstract Background: Previous data indicated that resonses in the re-translantation and the early ost-translantation eriods correlate with kidney allograft rejection and that differences in levels are associated with significant differences in graft rejection. The aim of the Work: Aim of this study is to identify ossible risk factors for sensitization that affect the results. Material and Methods: The resent cross-sectional study was erformed in 2010 on fifty ESRD atients (twenty five males and twenty five females) waiting kidney translantation in King Fahd Unit, Cairo University and a Private Center in Egyt. All clinical and laboratory data were recorded, including using comlement deendent cytotoxicity using lymhocytes. We tested the correlation between and different variables. results above 20% are considered ositive, while results below 20% are considered negative. Results: We found ositive in 12 cases (24%) in our study as the result is above 20% while 38 cases (76%) in our study are considered negative as result below 20%. Highly significant ositive correlation between levels and HCV ositivity, history of renal translantation and history of regnancy. Subanalysis of HCV ositive cases showed that blood transfusion was an essential finding in these atients. There was no statistically significant correlation between and age, gender, BMI, etiology of renal failure, duration of renal failure or dialysis, blood grou, blood or lasma transfusion, HBV, history of Rheumatoid arthritis, DM, HTN, SLE or history of drug intake. Conclusion: This study found that the only factors that correlate with are HCV ositive cases ( <0.001), revious translantation (<0.001) and regnancy history ( <0.001). Key Words: Pre-kidney translant reciients Donor Translantation. Introduction RENAL translantation is the treatment of choice for atients with end-stage renal disease (ESRD). Corresondence to: Dr. Usama Mohamady, The Deartment of Internal Medicine, Division of Nehrology, Faculty of Medicine, Cairo University. This oeration extends atient survival in the medium to long term and also imroves quality of life [1]. However, there are some roblems with renal translantation. First, the number of translant candidates is significantly greater than the number of available donors. Second, there are some absolute contraindications for translantation, the most imortant of which is immunological incomatibility [2]. Each translant candidate must be screened for cytotoxic anti-human leukocyte antigen (HLA) antibodies [3]. These antibodies are normally not resent in the general oulation, but they may be roduced during regnancy or in resonse to a blood transfusion, imlantation of an allograft, or dialysis. This rocess of anti-hla antibody roduction is called sensitization and such antibodies can be detected rior to translantation by crossmatching. Testing for anel-reactive antibodies () has been considered a routine method for detecting sensitization to HLA in kidney translant candidates [4]. levels have been found to have redictive value for graft survival and the occurrence of rejection eisodes [5]. Patients and Methods A cross-sectional study was erformed in 2010 on fifty ESRD atients (waiting kidney translantation in King Fahd Unit Kasr El Aini Hosital and a Private Center in Egyt). An interview was done to investigate exosure to otential sensitizing factors. We excluded atients who had recently Abbreviation: : Panel-Reactive Antibodies. 223

2 224 Eidemiology of in Pre Translant Renal Reciients received an agent known to affect : Lovastatin, hydralazine, rocaine, and alfa-methyl doa. Fifty atients were analyzed including twenty five males and twenty five females, Full history (including aetiology of renal failure, duration of hemodialysis, revious translantation, number of blood transfusions, regnancies, drug intake, DM, HTN, SLE, and rheumatic heart disease) was taken. Full clinical examination was done on each individual. Labs including blood grou, CBC, chemistry (urea, creatinine), virology (HCV, HBV, HIV) were erformed and recorded. The testing method was Comlement- Deendent Cytotoxicity, using lymhocytes (Biotest, Germany). Each serum samle was first incubated for 30 minutes with lymhocytes before addition of comlement. The result was assessed after 60 minutes. We screened for lymhocytes whether living or dead. Statistical methodology: Analysis of data was done by IBM comuter using SPSS (statistical rogram for social science version 12) as follows: -value >0.05 insignificant. <0.05 significant. <0.01 highly significant. Results Mean HD duration of 3±2.83 years. The average age of the grou was 38.9±9 years (range from 17 to 55 years), The duration of dialysis ranged between 2 months and 14 years (mean 3±2.83 years). 50% were males and 50% were females, The weight ranging between kg, with a mean of 72kg and standard deviation of 14kg, height ranging between cm, with a mean of 166cm and standard deviation of 10cm and a BMI ranging between 17-65kg/m 2 with a mean of 26kg/m 2 and standard deviation of 7kg/m 2. Table (1): Distribution of the studied grou as regard general data. General data Range Mean±SD Age (years) Weight (kg) Height (cm) BMI (kg/m 2 ) CKD duration (m=month), (y=year) Duration of hemodyalisis Gender: Male Female m-18y 2 months-14 years % of atients 50% 50% 38.9±9 72±14 166±10 26±7 4.7y±3.8 3 years±2.83 No. of atients Fig. (1): Distribution of studied grou regarding causes of renal failure. Table (2): Distribution of the studied grou as regard causes of CRF. Causes of CRF No. of atients % of atients GN 9 18 Unknown 8 16 CTIN 7 14 Luus 6 12 HTN 5 10 NSAIDs 4 8 Translant rejection 4 8 DM 2 4 PCKD 2 4 Gout 1 2 Amyloid 1 2 RA 1 2 The original renal disease as shown was GN in 9 cases (18%), unknown cause in 8 cases (16%), CTIN in 7 cases (14%), luus in 6 atients (12%), chronic graft rejection and drug nehroathy in 4 cases each (16%), gouty nehroathy, rheumatoid arthritis, amyloid in one case each (6%). Hyertension in 5 cases (10%), diabetic nehroathy and PCKD in 2 cases each (8%). Table (3): Distribution of the studied grou as regard blood grous. Blood grous % of atients No. of atients B+ve A+ve O+ve 14 7 AB+ve 10 5 A-ve 8 4 AB-ve 2 1 O-ve 2 1 The commonest blood grou among atients was B+ve in 17 (34%) cases, A+ve in 15 (30%) cases.

3 Usama Mohamady, et al. 225 Table (4): Distribution of the studied grou as regard regnancy. History of regnancy No. of atients % of atients Pregnancy: No Yes Mean±SD Duration since last regnancy Years 10± Table (5): Distribution of the studied grou as regard blood and lasma transfusions and number of units. History of blood & No. of % of lasma transfusion atients atients Blood transfusion: No Yes Plasma: No Yes (Mean±SD) Number of transfusions Blood 4± Plasma 1± (Mean±SD) Duration since last transfusion Blood 2.5±3 years 1 month-12 years Plasma 1.1±0.9 years 4 months-3 years This table shows that (64%) of the studied cases had a history of blood transfusion with average number of 4 units. History of lasma transfusion was in 20% of the studied cases with average number of 1 unit. Duration since last blood and lasma transfusion ranged between 1 month-12 years for blood and 4 months to 3 years for lasma, with an average of 2.5 years for blood and 1.1 years for lasma. Table (6): Distribution of the studied grou as regard ast history. Present and ast history No. of atients % of atients HTN HTN duration 5.4±3.6 years DM DM duration 7.7±4.8 years HCV HBV 1 2 HIV 0 0 SLE 6 12 Rheumatic heart 5 10 Previous oerations Table (7): Correlation between versus general data among the studied grou. General data Age > Weight > Height > BMI > CKD duration > Start of hemodialysis > Amount of blood units > Duration since last blood transfusion > Amount of lasma units > Duration since last lasma transfusion > Duration of HTN > Duration of DM > SBP > DBP > This table shows that there was no statistically significant correlation between versus different variables (age, weight, height, BMI, CKD duration, time of initiation of HD, amount of blood and lasma units transfused, duration since last unit of blood and lasma transfused, duration of HTN and DM, SBP and DBP) among the studied grou by using Searman correlation test. Table (8): Relation between versus revious blood transfusion among the studied grou. Blood transfusion No 14 (36.8%) 4 (33.3%) Yes 24 (23.2%) 8 (66.7%) >0.05 NS This table shows that with >20% cases who had a history of blood transfusion were (66.7%), comared to those with no history of blood transfusion (33.3%). In cases with 20%, those who had a history of blood transfusion were (23.2%), comared to those with no history of blood transfusion (36.8%). In our study there was no statistically significant difference between both grous as regard by using Fisher exact test. Table (9): Relation between versus revious lasma transfusion among the studied grou. Plasma transfusion No 32 (84.2%) 8 (66.7%) Yes 6 (15.8%) 4 (33.3%) >0.05 NS r

4 226 Eidemiology of in Pre Translant Renal Reciients This table shows that with >20% cases who had a history of lasma transfusion were (33.3%), comared to those with no history of lasma transfusion (66.7%). In cases with 20%, those who had a h story of lasma tr ansfusion were (15.8%), comared to those with no history of lasma transfusion (84.2%). In our study there was no statistically significant difference between both grous by using Fisher exact test. Table (10): Relation between versus revious regnancy. History of regnancy >20 No 14 (77.8%) 1 (14.3%) Yes 4 (22.2%) 6 (85.7%) <0.001 HS This table shows that with >20% cases who had a history of regnancy were (85.7%), comared to those with no history of regnancy (14.3%). In cases with 20%, those who had a history of regnancy were (22.2%), comared to those with no history of regnancy (77.8%). In our study there was a highly statistically significant difference between both grous by using Fisher exact test. No 20 Yes Fig. (2): Relation between versus history of revious regnancy Table (11): Relation between versus history of renal translantation. Renal translantation No 29 (76.3%) 5 (41.7%) Yes 9 (23.7%) 7 (58.3%) <0.05 S This table shows that cases with >20% cases who had history of renal translantation were (58.3%), comared to those with no history of renal translantation (41.7%). Cases with 20% who had history of renal translantation were (23.3%) comared to those with no history of renal translantation (76.3%). In our study there was a statistically significant difference between both grous by using Fisher exact test No >20 2 Yes Fig. (3): Relation between versus revious translantation. Table (12): Relation between versus history and laboratory data. Clinical history and laboratory data HCV 5 (13.2%) 5 (41.7%) <0.05 S HBV 1 (2.6%) 0 >0.05 NS DM 7 (18.4%) 4 (33.3%) >0.05 NS HTN 25 (65.8%) 9 (75%) >0.05 NS SLE 4 (10.5%) 2 (16.7%) >0.05 NS Rheumatic heart disease 4 (10.5%) 1 (8.3%) >0.05 NS This table shows that with 20%, HCV Ab+ve cases were (13.2%), while with >20% HCV-Ab+ve cases were (41.7%). There was a statistically significant difference between both grous as regard by using Fisher exact test. On the other hand there was no statistically significant difference with HBV-Ab+ve, DM, HTN, SLE and rheumatic heart disease as regard. >20 202( 0 HCV HBV DM HTN SLE Rheumatic Fig. (4): Relation between versus clinical history and laboratory data.

5 Usama Mohamady, et al. 227 Table (13): Relation between versus gender. Gender >20 Male 20 (52.6%) 5 (41.7%) Female 18 (47.4%) 7 (58.3%) >0.05 NS In our study there was no statistically significant difference between males and females as regard by using Fisher exact test. Table (14): Relation between versus blood grous among the studied cases. Blood grou X 2 B+ve 4 (33.3%) 13 (34.2%) >0.05 NS 4.2 A+ve 5 (41.7%) 10 (26.3%) O+ve 0 7 (18.4%) AB+ve 2 (16.7%) 3 (7.9%) A-ve 1 (8.3%) 1 (7.9%) AB-ve 0 1 (2.6%) O-ve 0 1 (2.6%) This table shows that atients with >20%, the most frequent blood grou was B+ve (34.2%) followed by A+ (26.3%), O+ve (18.4%), AB+ve (7.9%) and A-ve, O-ve, AB-ve each (1%). Patients with 20, the most frequent b ood grou was A+ve (41.7%) followed by B+ve (33.3%), AB+ve (16.7%), A-ve (1 %) and O+ve, O-ve, AB-ve each (0%). In our study there was no statistically significant difference between different blood grous as regard by using chi-square test. Table (15): Relation between versus different variables by logistic regression model. Indeendent redictors 2 Odd s (95%CI) Beta coefficient HCV <0.001 HS 1.9 (1-11.5) 0.98 Translantation <0.001 HS 1.3 ( ) 0.59 Pregnancy <0.001 HS 1.1 ( ) 0.47 This table shows that in our study cases with HCV-Ab+ve, history of renal translantation and those with history of regnancy are considered the most significant indeendent redictors of high level resectively. Table (16): Relation between blood transfusion and HCV. Blood transfusion Negative HCV Positive No 18 (100%) 0 Yes 22 (68.8%) 10 (31.3%) <0.001 HS This table shows that all HCV-Ab+ve cases had a history of blood transfusion, while all cases with no history of blood transfusion were HCV- Ab-ve. Cases with HCV-Ab-ve and had history of blood transfusion were (68.8%) while those with HCV-Ab+ve and had history of blood transfusion were (31.3%). In our study there was a highly statistically significant difference between history of blood transfusion and HCV-Ab+ve cases by using Fisher exact test. Table (17): Relation between blood transfusion and regnancy. History of blood transfusion History of regnancy No Yes No 6 (75%) 2 (25%) Yes 9 (52.9%) 8 (47.1%) >0.05 NS This table shows that females of the studied grou who received blood transfusion and had a history of regnancy were (47.1 %) while those with no history of blood transfusion nor regnancy were (75%). Meanwhile those who received blood transfusion with no history of regnancy were (52.9%), while those who didn t receive blood transfusion and had a history of regnancy were (25%). In our study there was no statistically significant difference between history of blood transfusion and history of regnancy by using Fisher exact test. Table (18): Relation between blood transfusion and gender. Blood Gender transfusion Male Female No 10 (55.6%) 8 (44.4%) Yes 15 (46.9%) 17 (53.1%) >0.05 NS This table shows that females of the studied grou who received blood transfusion were (53.1%) comared to males (46.9%), and those who didn t receive blood transfusion were (44.4%) comared to males (55.6%). In our study there was no statistically significant difference between history of blood transfusion and gender by using Fisher exact test. Discussion Develoment of is affected by various factors. Some of the factors such as revious translantation, regnancy and blood transfusion are already established factors for develoment of. In recent years several other factors such as infection, gender, and renin angiotensin system,

6 228 Eidemiology of in Pre Translant Renal Reciients have been imlicated in atients with elevated levels [6]. level was found to be significantly elevated in atients with angiotensin converting enzyme DD genotye due to renin angiotensin hyeractivity [7]. There are also reorts of naturally occurring HLA antibodies. There seems to be a ossible relationshi between formation of and auto-antibodies associated with autoimmune diseases [8]. It has already been suggested that atients with certain autoimmune diseases such as SLE often had T cell cytotoxic antibodies even without revious alloimmunization [9]. Some reorts suggested that the de novo aearance of donor-secific anti-hla antibodies in the ost-translantation eriod is usually associated with allograft rejection. In addition, the acute rejection rates seem to be higher when there is denovo aearance of donor-secific anti-hla antibodies in the ost-translantation eriod [10,11]. The aim of this study was to identify ossible risk factors for sensitization that affect the results. The resent cross-sectional study was erformed in 2010 on fifty ESRD atients (waiting kidney translantation in king Fahd Unit, Cairo University and a Private Center in Egyt). An interview was also done to investigate exosure to otential sensitizing factors. We excluded atients who had recently received an agent known to affect : Lovastatin [12], hydralazine, rocaine and alfamethyl doa [13]. A total of five atients were excluded from the study due to lovastatin theray and two atients due to alha-methyldoa intake. Fifty atients were included in the study (twenty five males and twenty five females). Age, Height, body mass index, blood grou, etiology of renal failure, history of viral infection, regnancy, drug intake, total number of blood and lasma transfusions received and revious translantation history were recorded for each individual. Blood transfusion information was obtained from the atient. levels above 20% were considered ositive. We tested the correlation between ositivity and different variables. Regarding results in our study, 12 cases (24%) were above 20%, while 38 cases (76%) were below than 20%. CKD duration ranged between 1-18 years, with a mean of 4.7 years and standard deviation of 3.8 years, with duration of hemodialysis ranging be- tween 2 months to 14 years with a mean of 3 years and standard deviation of 2.8 years. Talking about the causes of renal failure in the studied grou, with a total of 50 atients, 9 were due to GN (highest ercentage of the investigated grou, 18%), 8 due to an unknown cause (16%), 7 due to CTIN (14%), 6 were due to SLE (12%), 5 due to hyertension (10%), 4 due to drug intake (NSAIDs) (8%), 2 were due diabetes mellitus (4%), 2 due to PCKD (4%), 1 due to gout (2%), 1 due to amyloid (2%) and 1 due to RA (2%). We found no correlation between levels and the etiology of renal failure. This finding was suorted by Pour Reza, et al., [14]. As regard blood grous A+ve and B+ve were found to be the most frequent among the studied cases. We found that 36% vs 80% of the studied grou received no blood or lasma transfusion resectively. Also, 64% vs 20% received blood and lasma transfusions resectively. Average number of units was 4 vs 1 with a standard deviation of 3 vs 2 for blood and lasma transfusion resectively. The average time between the test and the last blood vs lasma transfusion was 2.5 vs 1.1 years resectively. As regard regnancy history among our studied cases, 40% of the females had regnancy history while 60% didn t get regnant. Talking about the resent and ast history, 68% and 22% of the studied cases had HTN and DM resectively with an average duration of 7.7 and 5.4 years resectively. Also, 12% had SLE, 10% had rheumatic heart disease, 20% were HCV-Ab+ve while 2% were HBV-Ab+ve, with no treatment received in both grous. We found also that 32% of the studied grou had a history renal translantation. In our study there was no statistically significant correlation between vs other variables among the studied grou including weight, height, BMI, CRF duration, amount of blood and lasma received, also duration since last unit received, duration of HTN and DM, SBP and DBP. Also there was no statistically significant correlation between and age of atients (>0.05). This agrees with the findings of Sezer et al., 1998 [15] who found no correlation between age of atients and levels. However Pour Reza Gholi et al., 2005 [14] found that age was correlated with

7 Usama Mohamady, et al. 229 levels (=0.014). Further analysis in that study revealed that age and levels were negatively correlated (atients older than 50 years had lower levels than the younger grous (= 0.018). They exlained these results by a reduction in the strength of the immunological resonse over time. We also studied the relation between and duration of dialysis. Duration of dialysis in our cases ranged between 2 months and 14 years with a mean of 3 years, standard deviation of 2.8 years. There was no correlation between levels and HD duration in our cases (>0.05). These data are suorted by Sezer et al., [15]. However, Pour Reza Gholi et al., [14] who found a statistical correlation between ositivity and HD duration. They attributed to the fact that longer duration of HD (mean 50±40 months). The longer the duration on HD, the greater the ossibility that they will encounter antigenic stimulants in blood transfusion and blood roducts [16]. The absence of a ositive correlation between and duration of HD in our cases can be exlained by the shorter duration of HD (mean 36±33 months) and the smaller number of cases (50 cases). Pour Reza Gholi et al., [14] found that levels of the samle taken after dialysis session was significantly higher than the one before dialysis (=0.0003), however they found no difference when they divided the cases into grous of negative/ ositive ( <10% as negative) and low/high ( <60% as low). Thus it seems that the most aroriate blood samling time may not be after the dialysis rocess. Among the studied cases, 64% and 20% received blood and lasma transfusions resectively. Average number of units was 4 and 1 with a standard deviation of 3 and 2 for blood and lasma transfusions resectively. Average time between the test and last blood vs lasma transfusion was 2.5 and 1.1 years resectively. We found no correlation between levels and blood vs lasma transfusions or the duration since last transfusion (>0.05). This agrees with the findings of Pour Reza Gholi et al., [14]. However other investigators [17,18] found that blood transfusion is an imortant factor in sensitization. Evaluating risk factors for sensitization in 244 ESRD atients. Soosay et al., 2003 found that all the highly sensitized atients ( levels >80%) had received at least one transfusion [17]. They reorted that 80% of the significantly sensitized atients ( levels 60% to 80%) and 60% of non sensitized subjects had been transfused. As regard the correlation between and revious regnancies, 14 out of 15 cases (77.8%) with no history of regnancy had a <20%, while 6 out of 10 cases (85.7%) with history of revious regnancy had a of >20%. These results showed that there is a highly significant statistical correlation between and revious regnancies (<0.001), The same findings were found by Kerman et al., [4]. On the otherhand our data do not agree with those of Pour Reza Gholi et al., [14] who found no correlation between levels and revious regnancies. Soosay et al., study have revealed that only 18% of women with a hist-ory of regnancy were non sensitized [17]. To study if the ositive correlation between and regnancy could be due to blood transfusion taken during labor or its comlications, we examined the relation between regnancy and blood transfusion. There was a history of regnancy in 10 out of 25 females and a history of blood transfusion in 17 out of 25 females. The correlation was insignificant (>0.05), showing that the correlation between ositive and regnancy is not related to concomitant history of blood transfusion. Discussing the correlation between and revious translantation, With 20%, 29 cases (76.3%) had no history of renal translant, while with >20% 7 cases (58.3%) had a history of renal translant, These results are showed that there is a statistically significant correlation between and revious translant ( <0.05). These data are suorted by the findings of Sezer et al., [14] and Pour Reza Gholi et al., [15]. We studied the relation between and HCV, we found that 5 out of 10 HCV-Ab+ve cases had a >20% comared to 5 out of 40 HCV-Abve cases had a of <20%, with a statistically significant difference between both grous (< 0.05). Then we tested the correlation between HCV and blood transfusion to see whether the effect on was due to HCV ositivity or due to blood transfusion received by these atients. All cases with no history of blood transfusion were HCV- Ab-ve (18 cases), while cases with a history of blood transfusion (32 cases) included all the 10 cases with HCV-Ab+ve and 22 HCV-Ab-ve cases. The correlation was highly significant ( <0.001) These data are suorted by the findings of Pour Reza Gholi et al., [14].

8 230 Eidemiology of in Pre Translant Renal Reciients There was no statistically significant correlation between and HBV, DM, HTN, SLE and rheumatic heart disease (>0.05). This difference may be due to the small number of atients with these articular diseases. There was no statistically significant correlation between and gender. However our results were as follows: 58.3% of females vs only 41.7% of males had a >20% while those with <20%, we had 47.4% females vs 52.6% males ( >0.05). This difference may be artially related to regnancy, where females tend to have more antibodies than males, however this is only observational with no solid statistically significant relation. Similar findings were found by Sezer et al., [15]. We studied the correlation between ositivity and blood grou. The distribution of cases was equal among both sexes (50% each). Our cases included almost all variants of blood grous with B+ve and A+ve the most frequent. The distribution of blood grous was B+ve in 34%, A+ve in 30%, A-ve in 8%, AB+ve in 10%, AB-ve in 2%, O+ve in 14% and O-ve in 2%. We found no correlation between and blood grou (>0.05), however blood grous A+ve & B+ve had the greater % of atients of (>20%), 41.7% and 33.3% resectively. Here this is only observational with no solid statistically significant relation. These data are suorted by the findings of Pour Reza Gholi et al., [14]. Finally we studied the relation between and HCV, revious translantation and revious regnancy using the logistic regression model. We concluded that these variables were the most significant indeendent redictors of a high in our study with odd s ratio for HCV (1.9), for revious translantation (1.3) and for revious regnancy (1.1). History of blood transfusion maybe an imortant contributing factor for a high in HCV ositive cases. Conclusion: There is statistically significant correlation between and HCV, revious renal translant and revious regnancies. No correlation between level vs age, etiology of renal failure, gender, blood transfusion, different blood grous and HD duration and the absence of a ositive correlation between level vs duration of HD can be exlained by the shorter duration of HD (mean 36±33 months) and the smaller number of cases (50 cases). Also no correlation between level vs HBV, diabetes mellitus, hyertension, systemic luus erythromatosis, rheumatoid arthritis or history NSAIDs intake, history of blood and lasma transfusions or the duration since last transfusion, We suggest it is due to that ESRD atients often have multile other contributing factors such as revious translantation and regnancy. Recommendations: We recommend to reeat the study on a bigger number of cases, to include cases of CKD before initiation of dialysis, to study the effect of dialysis and washed red blood cell transfusion on levels and also to follow the effect of graft nehrectomy on levels by time and we also recommend to study level in early ost translantation eriod with correlation to the occurrence of rejection. References 1- VELLA J.P. and SAYEGH M.H.: Risk factors of graft failure in kidney translantation. In: Rose B.D., ed. Wellesley Mass: Utodate, 12: 1, BRENNER B.M. and RECTOR F.C.: Brenner and Rector s the kidney. 7th ed. Philadelhia: WB Saunders, SINGH D., KIBERD B.A. and WEST K.A.: Imortance of eak in redicting the kidney translant survival in highly sensitized atients. Translant Proc., 35: 2395, KERMAN R.H., KIMBALL P.N., VAN BUREN C.T., et al.: Translantation, 53: 64, DEHKA R., PANIGRAHI A., AGGARWAL S.K., et al.: Influence of retranslant anel reactive antibodies on the ost translant sensitization status. Translant Proc., 34: 3082, LEE K.W., KIM S.J., LEE D.S., LEE H.H., JOH J.W., LEE S.K., OH H.Y., KIM D.J., KIM Y.G., HUH W.S., OH W.I. and B.B. LEE: Translantation Proceedings, 36: , AKÇAY A., OZDEMIR F.N., ATAÇ F.B., et al.: Angiotensin-converting enzyme genotye is a redictive factor in the eak anel-reactive antibody resonse. Translant Proc., 36: 35, OZDEMIR F.N., SEZER S., TURAN M., et al.: The effect os simvastatin on Panel reactive antibody and cross match ositivity. Translant Proc., 33: 2842, TONGIO M.M., FALKENRODT A., MITSUISHI Y., et al.: Natural HLA antibodies. Tissue Antigens, 26: 271, MORRIS P.J.: Kidney Translantation: Princiles and ractice. 5th ed., Philadelhia: WB Saunders, SCORNIK J.C., SALAMON D.R. and LIM P.B.: Translantation, 47: 287, MANSOUR I., MESSAED C., AZOURY M., et al.: Panel reactive antibodies using comlement deendent cytotox-

9 Usama Mohamady, et al. 231 icity and elisa in atients awaiting renal translantation or translanted atients: A comarative study. Translant Proc., 33: 2844, METZGER R.A., DELMONICO F.L. and FENG S.: Exanded criteria donors. Am. J. Translant, 3 (S4): , POUR REZA GHOLI F., DANESHVAR S., NAFAR M., FIROUZAN A. and FARROKHU F.: Einollahi Translantation Proceedings, 37: , SEZER S., OZDEMIR M., TURAN M., GUZ G., HE- BERAL A., KAYA S. and BILGIN N.: Translantation Proc., 30: , REVILLARD J.P., VINCENT C. & RIVERA S.: Anti B2 microglobulin lymhocytotoxic autoantibodies in systemic luus erythematosis. J. Immunol., 122: 614, SOOSAY A., O"NEILL D., COUNIHAN A., et al.: Causes of sensitization in atients awaiting renal translantation in Ireland. Ir. Med. J., 95: 109, 2003.