Controlling Goos-Hänchen shifts due to the surface plasmon effect in a hybrid system.

We have theoretically studied the Goos-Hänchen (GH) shifts of both the reflected and transmitted probe beams emerging from a cavity consisting of a hybrid system of a coupled quantum dot (QD) nanostructure and a metallic nanoparticle (MNP). It is realized that the GH shifts in the transmitted and reflected light beams can be enhanced due to the surface plasmon effect in the MNP. Also, it is shown that by adjusting the distance between QD and MNP and polarization control between probe field and major axis of the hybrid system, the simultaneous negative and positive GH shifts in reflected and transmitted light beams can occur. Moreover, the effects of the intensity and detuning of the coupling light on the GH shift properties of the reflected and transmitted lights have been discussed. We have found that under different parametric conditions of the hybrid system, the GH shifts of the reflected and transmitted light beams can be adjusted by tuning the intensity and controlling the detuning of the coupling field. The results show that our proposed model may be used for future optical sensor devices based on MNP hybrid systems.

The risk factors and laboratory diagnostics for post renal transplant tuberculosis: a case-control, country-wide study on definitive cases.

BACKGROUND: Tuberculosis (TB) is an important cause of morbidity and mortality in renal transplant recipients and, because of its infrequency and the lack of medical awareness, it is usually misdiagnosed. This study was carried out to determine frequency and weight of multiple risk factors for post kidney transplantation TB. METHODS: A total of 44 cases (0.3%), out of 12,820 patients from 12 major kidney transplantation centers in Iran from 1984 to 2003, were compared with 184 healthy transplant subjects who were transplanted by the same surgical team. RESULTS: The mean age of cases and controls was 37.7 (13-63) and 35.6 (8-67) years (P=0.3), respectively. The mean duration of pre-transplantation hemodialysis was 30.3 (3-168) months in cases and 18.2 (1-180) months in controls (P=0.03). A positive past history of TB was detected in 2 cases and 1 control (P=0.3). The mean doses of initial and maintenance immunosuppressive drugs in cases and controls were not significantly different. A total of 25 cases (56.8%) and 60 controls (32.6%) had rejection before diagnosis of TB (P=0.004; OR=2.7, CI(95%): 1.3-5.6). CONCLUSIONS: To our knowledge, this is the first study that demonstrated an increase in the risk of post-transplant TB by increasing the duration of pre-transplant hemodialysis and the number of post-transplant rejection episodes as 2 immunocompromised states. Further study is needed to clarify our new findings, specifically in relation to different immunosuppressive regimens.

Cyclosporine trough (C0) and 2-hour postdose (C2) levels: which one is a predictor of graft loss?

BACKGROUND: Compared with conventionally measured trough level (C0), cyclosporine 2-hour postdose (C2) concentrations show a better correlation with the area under the curve and acute graft rejection. OBJECTIVES: We evaluated the relationships of C0 and C2 with long-term graft survival among kidney transplant recipients. METHODS: In a case-control design, we selected 215 adult kidney recipients. Inclusion criteria were more than 18 years of age at transplantation and at least 6 months of follow-up. The case group consisted of patients with graft loss (n=17) and a control group, patients with functioning grafts (n=198). The C0 and C2 levels for the first 6 months posttransplantation, along with demographic and clinical data, were compared between the two groups using univariate analysis. P<.05 was considered to be significant. RESULTS: The mean age at transplantation was 40.5 +/- 16.5 years. The mean follow-up duration was 18 +/- 14 months. The mean C0 values for the case and control groups were 257.8 +/- 126.5 and 248.5 +/- 104.4 mumol/L, respectively (P>.05). The values for C2 were 712.7 +/- 273.2 and 886.2 +/- 266.9 mumol/L, respectively (P=.01). CONCLUSIONS: We observed that C2, but not C0, in the first 6 months posttransplantation were a predictor of long-term graft survival. The findings here in supported the results of other studies that have proposed cyclosporine concentration monitoring by C2 rather than C0 measurements.

Calcium and phosphorus metabolism disturbances after renal transplantation.

INTRODUCTION: Several studies have noted that, despite beneficial correction of abnormalities of mineral metabolism after successful renal transplantation, renal functional recovery is incomplete. Also, persistence of hyperparathyroidism and metabolic acidosis among patients with chronic impairment of graft function together with the use of loop diuretics and immunosuppressive drugs with adverse effects may alter mineral metabolism. We determined calcium and phosphorus levels in recipients. METHODS: This cross-sectional study enrolled 398 recipients in 2 medical centers in Iran from 1988 to 2004 to evaluate serum calcium and phosphorus levels after 1 month in relation to graft and patient survivals. Cyclosporine was the constant part of the immunosuppressive treatment in all study subjects. RESULTS: The median follow-up time was 8 months (range, 1-180 months). One and 10-year survival rates of patients were 97.9% and 91.1%. Mean (SD) serum calcium levels before and after transplantation were 8.79 (1.26) and 8.50 (1.39) mg/dL, respectively (P=.020). The mean (SD) phosphate levels before and after transplantation were 6.43 (2.42) and 3.64 (1.71) mg/dL, respectively (P=.000). There was no significant difference in survival considering changes in serum calcium and phosphorus levels. There was no correlation between serum calcium and phosphorus level changes among study patients. CONCLUSIONS: Despite reports suggesting hypercalcemia as a posttransplantation finding, we did not observe this condition, but, consistent with other reports in this field, we observed a significant decrease in serum phosphorus levels showing correction of this mineral level.

Hyperlipidemia after renal transplantation and its relation to graft and patient survival.

INTRODUCTION: Hyperlipidemia is a multifactorial event that frequently develops following renal transplantation and may worsen the patient's prognosis. The aim of this study was to evaluate the incidence and concomitant factors for hyperlipidemia. METHODS: We studied 687 renal transplant recipients from 1988 to 2004 using a cross-sectional design to determine the frequency of hypercholestrolemia and hypertriglyceridemia before and 1 month to 1 year after renal transplantation, to evaluate its relation to patient and graft prognosis in two medical centers in Iran. Cyclosporine was the constant part of immunosuppressive treatment in all study subjects. RESULTS: One and 5-year graft survival times were 94.23% and 81.34%, respectively. The prevalence of hypercholestrolemia after transplantation was 59.9%. Mean (+/- 2 SE) serum cholesterol levels before and after transplantation were 161.15 +/- 3.81 and 213.83 +/- 4.53 mg/dL respectively (P=.000). Triglycerides levels, were 159.99 +/- 13.08 and 196.28 +/- 19.6 mg/dL respectively. There was no significant correlation between cyclosporine dose, graft and patient survivals, and severity of hyperlipidemia (determined by cholesterol and triglyceride levels). CONCLUSIONS: Lipid metabolism abnormalities observed in this study were similar to other reports. There was no correlation with patient or graft survival. In addition, there may routes for development of hyperlipidemia other than adverse complications of immunosuppressive drugs.

Posttransplantation lymphoproliferative disorders in renal transplant recipients: report of over 20 years of experience.

INTRODUCTION: Despite the benefits of immunosuppressive medications to improve graft function, they have several adverse effects, such as development of neoplasms in renal transplant recipients. Posttransplantation lymphoproliferative disorders (PTLDs) are not uncommon complications, so we conducted a study to evaluate the characteristics of affected patients. METHODS: We enrolled 2117 kidney recipients from June 1984 to March 2004 in order to find pathological and clinical evidence of neoplasms. We collected and analyzed all data on PTLD patients. RESULTS: Overall there were 46 recipients with different types of neoplasms, among which the most common types were diseases of the skin (24 cases, 52.2%), Kaposi's sarcoma (15 cases, 32.6%), and PTLD (14 cases, 30.4%). The mean (+/- SD) age of PTLD patients at the time of transplantation was 37.86 +/- 9.67 years and 42.8% were women. Median and mean (+/- SD) time interval to PTLD diagnosis were 38.5 and 50.35 +/- 41.7 months, respectively (range 1 to 146 months). Types of PTLD in these patients were kidney lymphoma (14.3%); gastrointestinal (14.3%); brain lymphoma; tonsils; palatine; Hodgkin's lymphoma, large cell lymphoma, and acute lymphoblastic lymphoma (each 7.1%), with 28.6% unspecified types. The 1-, 5-, and 10-year patient survival rates after transplantation were 71.4%, 51.4%, and 44.3%, respectively. Despite discontinuing immunosuppressive therapy in PTLD patients, five of six surviving had graft function up to a mean time of 105.4 +/- 57.6 months after transplantation. CONCLUSION: Our findings showed that the prevalence of PTLD was 0.66%, which was less than reports from Western countries. The fact that there were surviving grafts for a considerable time despite discontinuing immunosuppressive therapy is of great importance.

Living unrelated versus living related kidney transplantation: 20 years' experience with 2155 cases.

PURPOSE: To compare the long-term results of kidney transplantation from living unrelated donors (LURDs) with that from living related donors (LRDs). MATERIALS AND METHODS: From 1984 to 2004, we performed 2155 kidney transplantations of which 374 were from LRDs and 1760 from LURDs. We reviewed and compared the long-term data from these cases. RESULTS: The LURD group included 64.2% men with an overall mean age of 33.46 +/- 14.61 (range 3 to 76) years. Laparoscopic donor nephrectomy was performed in 329 cases (18.7%) with mean follow-up of 45.68 +/- 46.80 months. The LRD group included 66.5% of male recipients with overall mean age of 28.97 +/- 9.58 (range 9 to 65) years. Laparoscopic donor nephrectomy was performed in 12 cases (3.2%) of LRDs with mean follow-up of 81.15 +/- 67.03 months. One-, 3-, 5-, 10-, and 15-year graft survivals among LRDs were 91.6%, 81.7%, 76.4%, 64.4%, and 48.4%; and for LURDs, 91.5%, 86.7%, 81.4%, 68.2%, and 53.2%, respectively (P = .07). Patient survivals for 1, 3, 5, 10, and 15 years in LRDs were 94.6%, 91.9%, 83%, 79.5%, and 73.9%, and in LURDs were 93.6%, 91.7%, 89.3%, 84%, and 76.4%, respectively (P = .14). CONCLUSION: The results of living unrelated kidney transplantation upon long-term follow-up with a large number of cases were as good as living related kidney transplantation. The organ shortage can be alleviated by using living unrelated kidney transplantation. To our knowledge this is the largest experience with long-term follow-up reported from one center to date.

Natural Killer Cell Subsets and IL-2, IL-15, and IL-18 Genes Expressions in Chronic Kidney Allograft Dysfunction and Graft Function in Kidney Allograft Recipients.

BACKGROUND: While acute rejection and early graft loss rates have decreased substantially over the past four decades, progressive chronic allograft dysfunction (CAD) still remains a common cause of late graft loss in kidney transplant recipients. OBJECTIVE: This study was conducted to investigate the percentage of natural killer (NK) cell subsets and IL-2, 15 and 18 genes expression in two groups of CAD and well-function graft (WFG) recipients. METHODS: 30 renal allograft recipients with biopsy-proven interstitial fibrosis/tubular atrophy (IF/TA) and impaired renal function, and 30 sex- and age-matched WFG patients were enrolled in this study. The percentage of NK cell subsets including NK CD56bright and NK CD56dim cells were determined by flowcytometry; IL-2, IL-15, and IL-18 genes expressions were assessed by real-time PCR. RESULTS: Compared to WFG patients, there was a significant (p<0.05) increase in the percentage of NK CD56bright cells in CAD patients. However, the difference in percentage of NK CD56dim cells or CD56dim/CD56bright ratio between the studied groups was not significant. In addition, IL-2, 15 and 18 genes expressions were almost similar in CAD and WFG patients. CONCLUSION: We found higher percentages of NK CD56bright subset in kidney transplant recipients with CAD without considerable changes in related cytokines' gene expression, suggesting a possible defect of NK cells maturation in these patients.

Concomitant nephrectomy of massively enlarged kidneys and renal transplantation in autosomal dominant polycystic kidney disease.

OBJECTIVES: We compared perioperative and intraoperative data of patients with end-stage renal disease (ESRD) due to autosomal dominant polycystic kidney disease (ADPKD) who received a renal allograft without native nephrectomy with ADPKD patients who underwent concomitant native nephrectomy of massively enlarged kidneys and renal transplantation to determine whether the latter approach is reasonable and safe. PATIENTS AND METHODS: From January 1987 to December 2003, 13 patients with ESRD due to ADPKD were stratified as 6 patients who underwent bilateral and 7 patients who underwent unilateral native nephrectomy in conjunction with renal transplantation (group A), versus 20 patients with ESRD due to ADPKD underwent renal transplantation without native nephrectomy (group B). Operative time, need for intraoperative transfusion, time to oral intake, duration of hospital stay, serum creatinine level on the day of discharge, readmission rate, and postoperative complications were compared for both groups. RESULTS: Mean intraoperative duration was significantly longer for patients in group A, but there was no statistically significant difference in the findings between both groups. CONCLUSIONS: Concomitant native nephrectomy of massively enlarged kidneys at the time of renal transplantation is reasonable and safe for patients with ESRD due to ADPKD.

Potential risk factors for hypersensitization reflected by panel-reactive antibodies in dialysis patients.

INTRODUCTION: The panel-reactive antibody (PRA) test has been considered to be a routine index of sensitization to human leukocyte antigens (HLA) in kidney transplant candidates. This study investigated the effect of potential risk factors and the time of blood sampling on PRA tests. METHODS: A total of 98 patients at two dialysis centers in Tehran were tested for PRA levels before and after dialysis sessions. We evaluated their history of potential sensitizing events and patient interviews for their association with PRA levels. Also we compared PRA levels obtained before and after dialysis. RESULTS: The mean age of the patients was 58.33 +/- 15.85 years. Only age and kidney transplantation history were correlated with PRA levels (r = .246, P = .014 and P = .0001, respectively). Logistic regression analysis revealed an association between age and PRA level (P = .037). Transplantation history was weakly correlated with PRA level (P = .076). History of pregnancy and transfusion, dialysis duration, gender, donor relation, and kidney allograft duration were not associated with PRA. PRA before dialysis sessions was significantly lower than that after dialysis (P = .0003). However, no difference was seen when divided into groups of negative/positive (PRA < 10% as negative) and high/low (PRA < 60% as low). CONCLUSION: Many factors expose patients to HLA as sensitizing factors. However, it seems that PRA level is not always predictable by such conditions. Furthermore, dialysis as a confounding procedure impacts PRA results; thus, when to obtain a blood sample is a crucial question.

Signs and symptoms of cytomegalovirus disease in kidney transplant recipients.

PURPOSE: To investigate the range of clinical presentations of cytomegalovirus (CMV) disease in kidney transplant recipients. MATERIALS AND METHODS: We retrospectively reviewed the records of hundred kidney recipients who developed CMV disease between 1984 and December 2002 for demographic characteristics, laboratory findings, and presenting signs and symptoms. RESULTS: The most common presentations were elevated serum creatinine in 74 patients, fever in 71, thrombocytopenia in 43, nausea in 32, vomiting in 25, elevated alkaline phosphatase in 24, leukocytosis in 22, and leukopenia in 21. Tissue involvement was relatively rare, but six patients had pneumonia, two had conjunctivitis, and one had vascular dermatitis. Four percent of the patients had received intravenous ganciclovir prophylaxis, and 7% had received oral ganciclovir prophylaxis. Fever was associated with number of hospitalizations (P = .006), elevated creatinine (P = .006), nausea (P = .017), vomiting (P = .031), and previous posttransplantation infections (P < .001). All the patients with conjunctivitis, pneumonia, pulmonary symptoms, and abnormal heart sounds and most of those with arthralgia, nausea, and vomiting were febrile during their CMV disease course. CONCLUSION: Our findings showed that leukocytosis should be considered as much as leukopenia when CMV disease is suspected. CMV-induced pneumonia is not common in renal transplant recipients compared to other organ transplant recipients. CMV invasion to other tissues is also rare. Finally, fever is a common symptom and important in assessing the severity and prognosis of the disease.

Development of malignancy following living donor kidney transplantation.

BACKGROUND: Malignancy following renal transplantation is an important medical problem during the long-term follow-up. We studied some features of the cancers that developed in our patients. METHODS: We retrospectively reviewed all patients who underwent renal transplantation and developed malignancy from July 1984 to July 2004. RESULTS: The 2117 patients who underwent living donor kidney transplantation during the 19-year period had a mean follow-up of 81.1 +/- 61 months. During the follow-up, 38 patients (1.8%) developed cancer: 14 Kaposi's sarcomas, 11 lymphoproliferative diseases, four squamous cell carcinomas of the skin, two basal cell carcinomas, one breast, one ovary, one melanoma, one seminoma, one lung, and one ovary. Mean age at transplantation in the malignancy cases was higher than the other recipients (43.5 +/- 12.1 vs 32 +/- 13.9 years) (P = .000). A Kaposi's sarcoma occurred earlier compared with the other cancers (23 +/- 22 vs 62 +/- 44 months P < .05); most of these patients were over 40 years at transplantation (P < .05). We also observed that patients treated with mycophenolate mofetil developed cancer earlier than the others (19 vs 52 months; P = .001). None of the cases with lymphoma had a history of antilymphocytic agent therapy. The 10-year patient survival was 73%. CONCLUSION: The prevalence of cancer (1.8%) was among the lowest compared with other studies possibly due to implementing a living donor kidney transplantation program that required a low frequency of induction therapy.

Pregnancy in kidney transplant recipients.

PURPOSE: Our aim was to investigate kidney allograft, obstetric, and maternal outcomes in pregnant women undergoing kidney transplantation in our center. METHODS: Retrospective data on 74 pregnancies in 60 patients were reviewed and completed through phone interviews were compared with information on a control group of female kidney recipients. RESULTS: Mean age of patients at transplantation was 26.55 +/- 4.72 years and the median interval between transplantation and pregnancy was 27.5 months. Gestational period was 8 months. Live birth was the outcome in 43.2% of pregnancies; 9.5% led to still birth, 24.3% were aborted, and obstetrical data of the remaining were unavailable. Among the 11 patients who became pregnant within 12 months after transplantation, we observed seven live births and four abortions. None of pregnancies that were accompanied by acute rejection episodes (ARE) were successful. Twenty-six patients experienced at least one ARE versus 23 patients of the control group (P = NS). However, the first ARE occurred later in the pregnant group (P = .028). Chronic rejection and graft loss were seen in 24 and 18 study group cases and 17 and 17 control cases, respectively (P = NS). One-, 3-, 5-, and 10-year graft survivals were 100%, 96.5%, 94.5%, and 77.1% in the pregnant group versus 93.2%, 85.7%, 81%, and 64.7% in the control group, respectively (P = .07). CONCLUSION: Pregnancy in kidney recipients seems to be safe for kidney allograft recipients even within the first year posttransplant. Nonetheless, the outcomes of pregnancy in this group of patients is not always favorable, especially when rejection occurs simultaneously.

Is HLA-DR6 a protective factor against posttransplantation diabetes mellitus?

BACKGROUND: Posttransplant diabetes mellitus (PTDM) has several pre- and posttransplant risk factors. METHODS: The incidence and risk factors of PTDM were retrospectively evaluated in 2117 kidney allograft recipients from June 1984 to March 2004. Type and dosage of immunosuppressive agents, pretransplant weight and human leukocyte antigen (HLA) phenotypes in PTDM patients were compared with 61 matched controls. RESULTS: Sixty-one cases (2.8%) developed PTDM requiring insulin or oral hypoglycemic therapy, out of which 47.5% were men and 52.5% were women, although only 35% of our overall recipients are women. Onset occurred at a mean of 489 days following transplantation. Patients receiving more than 15 mg/d prednisolone developed PTDM more often than those on less than 15 mg/d (P = .000). Similarly PTDM was more frequent among patients who received more than 300 mg/d cyclosporine compared with those on less than 300 mg/d (P = .015). Mean weight in PTDM cases and controls was 65 +/- 13.4 kg and 57 +/- 13.6 kg, respectively (P = .005). HLA-DR6 was observed in 12.2% of nonaffected subjects but in none of the PTDM group (P = .002). Conversely, HLA-DR8 was seen only in PTDM patients (P = .012). In addition HLA-A26 was more common among PTDM patients (P = .02) and HLA-DR52 more frequent in nonaffected subjects (P = .025). CONCLUSION: Our findings suggest that female sex, dosages of prednisolone and cyclosporine, pretransplant weight, and genetic factors are associated with an increased risk of PTDM. The rate of PTDM appeared to be independent of weight gain in the first year posttransplant. Protection against PTDM may be afforded by HLA-DR6 and possibly HLA-DR52. Conversely and higher incidence of diabetes has been associated with HLA-DR8 and HLA-A26.

Kidney retransplantation in comparison with first kidney transplantation.

INTRODUCTION: The aim of this study was to depict the outcome of second and third kidney allografts in comparison with first kidney allografts. METHODS: Among 2150 kidney transplantations are 103 second and 5 third transplantations. Demographic characteristics and survivals of retransplanted patients were compared with a randomly selected group of first kidney recipients, consisting of two cases matched with each retransplanted patient for age, gender, and date of transplantation. RESULTS: Retransplanted patients consisted of 78 men and 30 women of mean age 32.63 +/- 11.92 years. They had received kidneys from 91 living-unrelated and 17 living-related donors. Median followup was 27 months. One-, 2-, 3-, and 5-year graft survivals were 81.4%, 78.9%, 78.9%, and 73.7% among retransplants, versus 92.9%, 91.5%, 89.8%, and 85.3% in the control group, respectively (P = .0037). Patient survival was 96%, 94.6%, 92.4%, and 87.8% in the retransplant group versus 93.1%, 92.4%, 90.9%, 87.4% in the control group, respectively (P = .63). Also, graft survivals were slightly lower in female compared to male retransplant patients (P = .09). No significant difference in survival rates was seen in different age groups. CONCLUSION: It seems that kidney retransplantation can yield desirable outcomes, albeit relatively lower graft survivals.

Impact of Ramadan fasting on renal allograft function.

Fasting during the holy month of Ramadan is a religious duty for all healthy adult Muslims. They are only allowed to eat and drink between sunset and dawn. This study was designed to find the effect of Ramadan fasting on allograft function. We prospectively studied 19 kidney transplant recipients who voluntarily chose to fast during Ramadan versus 20 matched recipients, who had not fasted for 3 consecutive years. Data were recorded before, during, and after the fasting month. The mean posttransplant periods in the fasting and control groups were 52.6 +/- 30.3 and 56.6 +/- 30.0 months, respectively. A statistical analysis showed no significant changes in serum creatinine concentrations before and after Ramadan 1.07 +/- 0.24 versus 1.08 +/- 0.22 mg/dL (P > .05) and 1.00 +/- 0.24 versus 1.03 +/- 0.28 mg/dL (P > .05) in fasting and control groups, respectively. The results did not show any adverse effects of fasting in recipients with stable renal function. In conclusion, our study suggests that fasting during the month of Ramadan is safe and has no significant harmful effects on kidney transplant recipients with normal renal function.

A randomized prospective trial of oral versus intravenous ganciclovir for prophylaxis of cytomegalovirus infection and disease in high-risk kidney recipients.

PURPOSE: This study was designed to compare the efficacy and safety of oral versus intravenous ganciclovir in high-risk kidney recipients. METHODS: Thirty-four, cytomegalovirus (CMV) seropositive recipients of kidneys from seropositive donors who had undergone antilymphocytic immunosuppressive therapy were assigned randomly to oral (1000 mg, three times a day, 12 weeks) versus intravenous (5 mg/kg, 2 weeks) ganciclovir prophylaxis. Follow-up was performed for 12 months. The patients were evaluated for clinical and laboratory outcomes regarding CMV serostatus, CMV disease, graft outcome, and ganciclovir side effects. RESULTS: Sixteen patients in the oral group and 14 in the intravenous group completed the study. CMV infection occurred in 6 (37.5%) and 5 (35.7%) cases in the oral and intravenous groups, respectively (P = NS). The mean interval between prophylaxis initiation and the first positive CMV Ag result was 3 +/- 2.19 months, with no significant difference between the two groups. Only two patients in the intravenous group experienced CMV diseases, which were not tissue-invasive. Acute rejection episodes were observed in nine out of 30 recipients, but it did not show any association with the prophylaxis regimen or CMV serostatus. The patients tolerated oral ganciclovir well; the compliance percent was 81.6%. No complication was reported. CONCLUSION: Oral and intravenous ganciclovir showed no significant difference to reduce the rate of CMV infection among high-risk kidney recipients. Oral ganciclovir was also effective and safe for the prevention of CMV disease. Moreover, it seems that CMV infection was not associated with acute rejection episodes.

Outcome of Kaposi's sarcoma and graft following discontinuation of immunosuppressive drugs in renal transplant recipients.

PURPOSE: Owing to the use of immunosuppressive drugs, renal transplant recipients are at risk for malignancies including Kaposi's sarcoma (KS). Following the diagnosis, physicians tend to decrease the doses of immunosuppressive drugs to lower tumor progression rate. On the other hand, those who receive lower doses of immunosuppressive drugs are at a higher risk for acute rejection. In this study, we evaluated the outcome of KS on renal allografts following discontinuation or decrease in the doses of drugs. METHODS: Since 1984, 14 (nine men and five women) among 2000 cases of renal transplantation have been diagnosed as KS. In 11 patients, cyclosporine was completely discontinued, the dosage was decreased to half of the initial dose in other cases. Except one case, we discontinued either azathioprine or mycophenolate mofetil. RESULTS: During 57 months of follow-up on average, the serum creatinine level remained normal in 10 but increased in four cases. Kidney function deteriorated in two of these four patients at the beginning of study. Three patients died with normal serum creatinine levels. Discontinuation of immunosuppressive drugs caused complete remission of KS in all patients except one who received chemotherapy. CONCLUSION: Discontinuation of immunosuppressants following the diagnosis of KS caused complete remission of this cancer in almost all patients and seemed to be relatively safe for kidney graft function.

Erythrocytosis after renal transplantation: review of 101 cases.

Posttransplant erythrocytosis is increasingly recognized as a complication of kidney transplantation. In a retrospective analysis of 500 recipients, we observed 101 patients (20.2%) with persistent elevation of hematocrit value. It was more frequent in men (82.2%) than women (17.8%). It occurred 2 to 50 months after engraftment (mean value was 11.2 +/- 8.9 months), but most often developed in the first 24 months (86%). Spontaneous remission of established erythrocytosis was observed in all cases within 3 to 93 months. It frequently occurred in patients with a well-functioning renal graft; in 82.2% of cases the serum creatinine concentration was less than 1.5 mg/dL. It was 1.5 to 2 mg/dL in 15.8% of patients. There was no correlation between diabetes mellitus and erythrocytosis, compared with a control group. It was more common in patients who received cyclosporine compared to those who were not on cyclosporine. Predisposing factors included male gender, retention of native kidneys, cyclosporine use, and a rejection-free course with a well-functioning renal graft. In conclusion, posttransplantation erythrocytosis, a frequent problem in renal transplant patients, is a self-limited complication that can result in thromboembolic disease.

Renal allograft accumulation of technetium-99m sulfur colloid as a predictor of graft rejection.

Differentiation between rejection (the most common cause) and many other possibilities for detrimental effects on graft function represents a difficult issue to diagnose the cause of renal allograft dysfunction. This study was designed to determine whether technetium-99m sulfur colloid (TSC) accumulation predicted graft rejection. We prospectively studied 54 episodes of allograft dysfunction in 53 kidney transplant recipients who underwent TSC scintiscanning and graft biopsy. Visual analysis of TSC uptake compared uptake, in the allograft with that in the marrow of the fifth lumbar vertebra (L5). A 3+ result meant that allograft uptake was greater than L5 marrow uptake; 2+, the same; 1+, less and finally 0, no allograft uptake. Transplant accumulation of 2+ or more was considered consistent with rejection (P = .01). Allograft biopsies interpreted based on the Banff Working Classification showed rejection in 45 of 54 renal biopsies with 42 the biopsy-proven rejection episodes showing at least 2+ graft uptake. Furthermore, this nuclear medicine technique had a sensitivity of 93.3%, a specificity of 44.4%, a positive predictive value of 89.3%, a negative value of 57.1% and an efficiency of 83.3% for the diagnosis of renal allograft rejection.