Critical points and potential pitfalls of outbreak of IMP-1-producing carbapenem-resistant Pseudomonas aeruginosa among kidney transplant recipients: a case-control study.

BACKGROUND: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) infection after kidney transplantation (KT) is associated with high mortality. AIM: To analyse an outbreak of infection/colonization with IMP-1-producing CRPA on a KT ward. METHODS: A case-control study was conducted. Cases were identified through routine surveillance culture and real-time polymerase chain reaction for carbapenemase performed directly from rectal swab samples. Controls were randomly selected from patients hospitalized on the same ward during the same period, at a ratio of 3:1. Strain clonality was analysed through pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing was performed for additional strain characterization. FINDINGS: CRPA was identified in 37 patients, in 51.4% through surveillance cultures and in 49.6% through clinical cultures. The median persistence of culture positivity was 42.5 days. Thirteen patients (35.1%) presented a total of 15 infections, of which seven (46.7%) were in the urinary tract; among those, 30-day mortality rate was 46.2%. PFGE analysis showed that all of the strains shared the same pulsotype. Multilocus sequence typing analysis identified the sequence type as ST446. Risk factors for CRPA acquisition were hospital stay >10 days, retransplantation, urological surgical reintervention after KT, use of carbapenem or ciprofloxacin in the last three months and low median lymphocyte count in the last three months. CONCLUSION: KT recipients remain colonized by CRPA for long periods and could be a source of nosocomial outbreaks. In addition, a high proportion of such patients develop infection. During an outbreak, urine culture should be added to the screening protocol for KT recipients.

Critical points and potential pitfalls of outbreak of IMP-1-producing carbapenem-resistant Pseudomonas aeruginosa among kidney transplant recipients: a case-control study

Background Carbapenem-resistant Pseudomonas aeruginosa (CRPA) infection after kidney transplantation (KT) is associated with high mortality. Methods We analysed an outbreak of infection/colonization with IMP-1-producing CRPA on a KT ward, conducting a case-control study. Cases were identified through routine surveillance culture and real-time polymerase chain reaction (PCR) for carbapenemase performed directly from rectal swab samples. Controls were randomly selected from patients hospitalized on the same ward during the same period, at a ratio of 3:1. Strain clonality was analysed through pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing was performed for additional strain characterization. Results CRPA was identified in 37 patients, in 51.4% through surveillance cultures and in 49.6% through clinical cultures. The median persistence of culture positivity was 42.5 days. Thirteen patients (35.1%) presented a total of 15 infections, of which 7 (46.7%) were in the urinary tract, among those, 30-day mortality rate was 46.2%. PFGE analysis showed that all of the strains shared the same pulsotype. Multilocus sequence typing analysis identified the sequence type as ST446. Risk factors for CRPA acquisition were hospital stay > 10 days, re-transplantation, urological surgical re-intervention after KT, use of carbapenem or ciprofloxacin in the last three months and low median lymphocyte count in the last three months. Conclusions KT recipients remain colonised by CRPA for long periods and could be a source of nosocomial outbreaks. In addition, a high proportion of such patients develop infection. During an outbreak, urine culture should be added to the screening protocol for KT recipients.

Donor transmission intestinal carcinoma after kidney transplantation: case report.

Tumor transmission is a rare complication of organ transplantation. Despite several improvements in excluding donor malignant disease, there continue to be reports of unknown tumors in the donors. The risk of having a donor with an undetected malignancy ranges between 1.3% and 2%. The cases of two kidney transplant recipients who had intestinal carcinoma transmitted from the same deceased donor are described. The clinical presentation, previous data, and management options are discussed. As a result of the increase in the overall donor pool, using extended criteria donors, donors of extreme ages, donors with prolonged intensive care admission, and donors who may potentially transmit disease to their recipients, the risk of tumor transmission and also infections should be considered.

Pneumocystis jirovecii pneumonia with an atypical granulomatous response after kidney transplantation.

Pneumocystis jirovecii pneumonia (PCP) continues to be a leading cause of morbidity and mortality in kidney transplant recipients. Granulomatous PCP is an unusual histological presentation that has been described in a variety of immunosuppressive conditions. Previous studies have demonstrated an association between granulomatous disorders and hypercalcemia, the purported mechanism of which is extrarenal production of 1,25-dihydroxyvitamin D by activated macrophages. Here, we report a case of granulomatous formation in a kidney transplant recipient with PCP who presented with hypercalcemia and suppressed parathyroid hormone, both of which resolved after successful treatment of the pneumonia. In immunocompromised patients, pulmonary infection associated with hypercalcemia should raise the suspicion of PCP and other granulomatous disorders.

Single center experience with elective surgical patients as living kidney donors.

PURPOSE: To report a single center experience with elective surgical patients as living kidney donors. METHODS: We retrospectively analyzed a prospective database of 458 living kidney donors from September 2005 to May 2011. Fifteen (3.2%) of them were elective surgical patients simultaneously undergoing living donor nephrectomy. We reviewed age, gender, operative time, intraoperative blood transfusion, intra- and postoperative complications, as well as length of hospital stay. Recipients were evaluated for delayed graft function. Four hundred forty-three patients undergoing living donor nephrectomy alone composed the control group. RESULTS: Among the elective surgical patients group, the mean (range) operative time was 155 (90 to 310) minutes and mean (range) length of hospital stay was 3 (2 to 9) days. One (6.7%) recipient displayed delayed graft function. Among the regular living kidney donors group, the mean (range) operative time was 100 (70 to 150) minutes, mean (range) length of hospital stay was 3 (2 to 5) days, and delayed graft function was observed in 5.6% of recipients. Only operative time (P = .03) was significantly different between the groups. CONCLUSIONS: Elective surgical patients are potential donors who may be treated at the same time as the living donor nephrectomy.

De novo thrombotic microangiopathy after kidney transplantation: clinical features, treatment, and long-term patient and graft survival.

INTRODUCTION: Posttransplant thrombotic microangiopathy (TMA)/hemolytic uremic syndrome (HUS) can occur as a recurrent or de novo disease. METHODS: A retrospective single-center observational study was applied in order to examine the incidence and outcomes of de novo TMA/HUS among transplantations performed between 2000 and 2010. Recurrent HUS or antibody-mediated rejections were excluded. RESULTS: Seventeen (1.1%) among 1549 kidney transplant recipients fulfilled criteria for de novo TMA. The mean follow-up was 572 days (range, 69-1769). Maintenance immunosuppression was prednisone, tacrolimus (TAC), and mycophenolic acid in 14 (82%) patients. Mean age at onset was 40 ± 15 years, and serum creatinine was 6.1 ± 4.1 mg/dL. TMA occurred at a median of 25 days (range, 1-1755) after transplantation. Nine (53%) patients developed TMA within 1 month of transplantation and only 12% after 1 year. Clinical features were anemia (hemoglobin < 10 g/dL) in 9 (53%) patients, thrombocytopenia in 7 (41%), and increased lactate dehydrogenase in 12 (70%). Decreased haptoglobin was observed in 64% and schistocytes in 35%. Calcineurin inhibitor (CNI) withdrawal or reduction was the first step in the management of 10/15 (66%) patients, and 6 (35%) received fresh frozen plasma (FFP) and/or plasmapheresis. TAC was successfully reintroduced in six patients after a median of 17 days. Eight (47%) patients needed dialytic support after TMA diagnosis and 75% remained on dialysis. At 4 years of follow-up, death-censored graft survival was worse for TMA group (43.0% versus 85.6%, log-rank = 0.001; hazard ratio = 3.74) and there was no difference in patient survival (53.1% versus 82.2%, log-rank = 0.24). CONCLUSION: De novo TMA after kidney transplantation is a rare but severe condition with poor graft outcomes. This syndrome may not be fully manifested, and clinical suspicion is essential for early diagnosis and treatment, based mainly in CNI withdrawal and FFP infusions and/or plasmapheresis.

Malakoplakia after renal transplantation in the current era of immunosuppressive therapy: case report and literature review.

Malakoplakia is a rare chronic granulomatous disease of unknown cause. It is thought to be caused by an acquired bactericidal defect of macrophages. Malakoplakia is associated with chronic infections and immunosuppression. Although it occurs mainly in the urinary tract, it has already been reported in almost every organ system. The isolation of bacteria, especially Escherichia coli, is common in malakoplakia patients. Here, we present a case of primary cutaneous malakoplakia in a kidney transplant recipient who had been taking prednisone, tacrolimus, and mycophenolate. Culture of a lesion grew Burkholderia cepacia complex. Treatment with high doses of trimethoprim-sulfamethoxazole was successful. We also present a systematic review of the literature, identifying 4 previously reported cases of malakoplakia after renal transplantation under similar immunosuppressive therapy, most occurring in the urinary tract or perineum and following benign courses to cure. Data in the literature suggest that malakoplakia has become even rarer since changes were made in the immunosuppressive therapy employed after kidney transplantation.

Protective effect of N-acetylcysteine on early outcomes of deceased renal transplantation.

We investigated the effects of the antioxidant N-acetylcysteine (NAC) on early outcomes of deceased donor renal transplantation. Between April 2005 and June 2008, adult primary graft recipients of deceased renal donors were assigned to treatment (n = 38) or control (n = 36) groups and evaluated for 90 days and one year after renal transplantation. The treatment group received NAC orally (600 mg twice daily) from day 0 to 7 postoperatively. Renal function was determined by serum creatinine, MDRD and Cockcroft-Gault estimated GFR (eGFR), delayed graft function (DGF) and dialysis free Kaplan-Meier estimate curve. Serum levels of thiobarbituric acid reactive substances (TBARS), were employed as markers of oxidative stress. The NAC group displayed a lower mean serum creatinine during the first 90 days (P = .026) and at 1 year after transplantation (P = .005). Furthermore, the NAC group showed a higher mean eGFR throughout the first 90 days and at 1 year. DGF was lower among the NAC group (P = .017) and these recipients required fewer days of dialysis (P = .012). Oxidative stress was significantly attenuated with NAC (P < .001). Our results suggested that NAC enhanced early outcomes of deceased donor renal transplantation by attenuating oxidative stress.

Non-human leukocyte antigen antibodies reactive with endothelial cells could be involved in early loss of renal allografts.

Preformed donor-specific human leukocyte antigen (HLA) antibodies have been associated with allograft dysfunction and failure. However, recipients of HLA-identical kidneys can develop acute humoral rejection, implicating putative pathogenic antibodies that are directed against non-HLA antigens. We investigated the presence of endothelial cell-reactive antibodies in 11 patients who experienced early loss of their transplanted kidneys owing to humoral rejection and 1 loss from renal venal thrombosis. We examined the potential efficacy of intravenous immunoglobulin to block the binding of these antibodies, as previously suggested for anti-HLA antibodies.

Multifocal renal allograft biopsy: impact on therapeutic decisions.

OBJECTIVE: There are no data to support the suggestion that samples removed from one segment of the transplanted kidney are representative of the whole graft. The aim of this study was to compare the histological differences between biopsies obtained from different portions of the renal allograft and their impact on treatment recommendations. PATIENTS AND METHODS: Two hundred percutaneous biopsies were performed on kidney allografts and samples were collected from the upper and lower poles (100 kidneys). All samples were randomized and blindly reviewed. We obtained the discordance rates between the poles for the grading of acute rejection and for the diagnosis of nephrotoxicity due to immunosuppression. We also checked if the differences found were sufficient to call for different clinical recommendations. These values were compared with the intrapathologist variation rates. RESULTS: In 70 kidneys adequate sampling was obtained from both poles. The diagnosis of acute rejection were made in 17. The discordance rate between the upper and lower poles was 82.3% (kappa = 0.34), higher than the intrapathologist variation (P = .002). Nephrotoxicity was found in 14 kidneys. The discordance rate between the upper and lower poles was 28.6% (kappa = 0.88), with no difference compared with the intrapathologist variation. In 14 of the 70 kidneys (25.7%), discordances between poles had impact on clinical recommendations, most of these cases due to different gradings of acute rejection (78%). This number was higher than the intrapathologist variation (P = .04). CONCLUSIONS: The histopathological changes in the kidney allograft are not always homogeneous. This heterogeneity may affect the therapeutic recommendations.

Identifying cyclosporine blood levels associated with the prevention of renal transplant rejection: a single-center, randomized prospective study.

Multiple-drug therapy may allow reduced individual drug doses with fewer side effects. Blood levels of cyclosporine (CsA) necessary to avoid rejection may vary with different drug combinations. Fifty-eight kidney transplant patients were randomized into two groups: 25 subjects were assigned to the 4-hour area under the curve (AUC(0-4)) Cohort-the "high arm" (4500 to 5500 ng . h/mL)--1 and 33 to the AUC(0-4) "low arm" (2400 to 3400 ng . h/mL). After CsA introduction, AUC(0-4) was drawn on days 4, 7, 14, 21, 28, 42, 56, 70, 84, 90. We compared the proportion of rejection versus rejection-free patients, according to the CsA exposure. Logistic regression analysis showed that an AUC(0-4) of > or =4000 ng . h/mL or a 2-hour cyclosporine level (C(2)) of > or =1450 ng/mL predicted a rejection-free course among patients not receiving induction therapy. When either basiliximab or thymoglobulin was administered, a C(2) and AUC(0-4) of 1043 +/- 151 ng/mL or 3146 +/- 262 ng . h/mL, respectively, were associated with a rejection-free course. Our findings confirm the need for different CsA levels to prevent rejection according to induction therapy. Induction with either basiliximab or thymoglobulin allows reduced CsA levels during the first 3 months after renal transplantation.

Induction versus noninduction therapy in kidney transplantation: considering different PRA levels and different induction therapies.

To evaluate the rate of acute cellular rejection (ACR) and long-term results in different levels of anti-HLA sensitization, using noninduction or different induction therapies, 763 patients who underwent transplantation from January 1995 to December 2001 were evaluated: 213 patients received induction therapy, 71 received Thymoglobulin (Thymo), 66 Simulect, and 44 OKT3. Follow-up time was at least 1 year for all groups. The Simulect group included older recipients and the OKT3 group had more female patients. Simulect and OKT3 groups had more black patients; Thymo and OKT3 groups had more retransplantations. PRA was low in the noninduction group (mean, 7%) and about the same in the Simulect and Thymo groups (mean, 30%). OKT3 was the most sensitized group (mean = 59%). Dialysis during the first posttransplantation week was more frequent among the induction groups (43% vs 65%; P <.005). Fewer patients experienced rejection episodes in the Thymo group (20% vs 50%; P =.02). Patients were classified according to their level of sensitization, and the Thymo group showed the lower rejection rates in all levels (mean, 20%; P =.001). When analyzing PRA >50%, the Thymo group showed lower rejection rates (12% vs 50%; P =.02). At this level of sensitization, there was no significant difference on graft loss and death with a functioning graft. There was a trend to more cytomegalovirus (CMV) disease in the Thymo group (33% vs 23%; P =.08). Two PTLD were diagnosed, both in the noninduction group. Renal function was better in the Thymo group (1.3 mg/dL). In conclusion, Thymo showed lower ACR rates in all PRA groups. No significant differences in CMV infection, tumors, and patient survival were observed.

Comparison of palpation-guided and ultrasound-guided biopsies in transplanted kidneys.

UNLABELLED: Biopsy is the gold standard for the diagnosis of conditions affecting the function of renal allografts. Obtaining representative tissue in biopsies is critical but these procedures are associated with up to 9% of complications and 20% of inadequate material. Although ultrasound guidance allows perfect control of depth and location of the graft, there is controversy regarding the cost-benefit of its use and reports of unsuitable material in ultrasound-guided biopsies are still high. PURPOSE: To compare ultrasound with the palpation method to guide biopsies in order to see if there is any difference between both methods and which one is better. PATIENTS AND METHODS: The casuistic consisted of 82 renal transplant patients (32 female and 50 male patients, age ranging between 5 and 64 yr; m=31.2 yr) randomized into two groups: GI, palpation-guided; GII, ultrasound-guided. Fifty-six biopsies were performed in GI and 66 in GII. RESULTS: Number of glomeruli, arcuate, and interlobar arteries and arterioles were compared in the two groups and were 503 (m=10) vs. 801 (m=12.9), 24 (m=0.5) vs. 38 (m=0.6), 104 (m=2.1) vs. 154 (m=2.5), and 174 (m=3.5) vs. 264 (4.3), respectively (p<0.05). Inadequate material for analysis in GI and GII was 7.1 and 7.6%, respectively (p=0.72). CONCLUSIONS: Although ultrasound guidance improves the number of glomeruli, arcuate, and interlobar arteries, as well as arterioles, compared with palpation-guided biopsies, there is no difference in the rate of adequate material between the two methods.

Catheter-associated urinary infection in kidney post-transplant patients.

CONTEXT: There is still controversy as to the use and dosage of antimicrobial prophylaxis of the urinary infection associated with urethral catheterization in the post renal transplant period. OBJECTIVE: To determine whether patients develop urinary infection during short-term urethral catheterization after renal transplant without routine antimicrobial prophylaxis. DESIGN: Prospective study. SETTING: Kidney Transplantation Unit. SAMPLE: 20 patients submitted to non-complicated kidney transplant, with a normal urinary tract and no risk factors present regarding urinary infection. Aged 15 to 65 years. MAIN MEASUREMENTS: Before the transplant, material from the urethral meatus and urine were collected for culture. After the transplant, in the period during which the patient was with short-term urethral catheterization (4 to 5 days), material from the urethral meatus and urine from the bladder and the collecting bag were taken daily from all recipients for culture. RESULTS: There was a predominance of coagulase-negative Staphylococcus and S. viridans in the normal urethral meatus flora and in the first two days of urethral catheterization. After the second day, there was a predominance of E. coli and E. faecalis. Urinary infection did not occur during the period of urethral catheterization. In the follow up only one female patient (7%) had asymptomatic bacteriuria caused by E.coli after the withdrawal of the urethral catheter. CONCLUSIONS: Infection urinary does not occur during the period of urethral catheterization in kidney post-transplant patients. Thus, antimicrobial prophylaxis is not recommended for these patients to prevent urinary infection.

Incisional hernia and its repair with polypropylene mesh in renal transplant recipients.

PURPOSE: We evaluate the incidence of incisional hernia after kidney transplantation, predisposing factors and the results of surgical repair with polypropylene mesh. MATERIALS AND METHODS: We reviewed the records of 371 consecutive kidney transplants performed between April 1995 and February 2000. Patients with clinical signs of hernia at the transplant incision site were included in the study. Predisposing factors for incisional hernia were also reviewed. A prospective protocol of surgical correction was established using polypropylene mesh and patient outcome was studied. RESULTS: We identified 14 patients (3.8%) with an incisional hernia at the transplant incision site. Hernias developed 3 to 840 days after transplant surgery and were significantly more common in white (p = 0.019) and cadaveric graft (p = 0.02) recipients. Predisposing factors in 11 cases included complications of transplant surgery in 7, bladder obstruction in 2, large polycystic kidneys in 1 and chronic pulmonary disease in 1. Surgical repair was performed by primary fascial approximation and polypropylene mesh reinforcement in 13 cases and by pre-peritoneal mesh placement in 1. Minor subcutaneous wound infection developed in 1 patient. No relapses were noted at a mean followup of 17.8 months. CONCLUSIONS: In the majority of cases incisional hernia develops in the first 3 months after transplant surgery. The incidence is significantly higher in white patients and after cadaveric donor transplantation. Surgical complications of transplant surgery are important predisposing factors for incisional hernia after kidney transplantation. Surgical repair using polypropylene mesh is safe and effective in this group of patients.

Introduction of mycophenolate mofetil and cyclosporin reduction in children with chronic transplant nephropathy.

Chronic transplant nephropathy (CTN) is the most important cause of kidney graft dysfunction. Studies in adult populations have reported a beneficial effect of non-nephrotoxic mycophenolate mofetil (MMF) on graft function in this setting. However, few studies were reported in children in this setting. We therefore reviewed the charts/medical records of renal transplanted patients < 18 yr of age at a single center who had switched from azathioprine to MMF as a result of progressive loss in graft function, for which vascular, infectious, and urological causes were excluded. Serum creatinine (SCr) and calculated creatinine clearance were compared prior to and after MMF introduction. Thirteen patients (nine male/four female), followed-up for 59.3 +/- 35.4 months after transplantation, were analyzed. Age at MMF introduction was 14.2 +/- 3.6 yr. In 11 patients a previous biopsy had shown features of CTN and four patients also presented signs of chronic cyclosporin A (CsA) nephrotoxicity. MMF was started at a dose of 1211 +/- 351 mg/day, and the CsA dose was decreased from 6.69 +/- 3.15 mg/kg/day 6 months before MMF to 4.8 +/- 2.3 mg/kg/day at the time of MMF introduction. CsA was withdrawn in four patients. The median (25-75%) SCr value increased from 1.60 mg/dL (range 1.3 to 1.87 mg/dL) 6 months before MMF to 2.2 mg/dL (range 1.87-2.32 mg/dL) when MMF was introduced. Six months after introduction of MMF, the SCr level had decreased to 1.5 mg/dL (range 1.2-1.8 mg/dL) and remained stable until the last follow-up (17.5 +/- 9.2 months after MMF was started). A similar pattern occured with calculated SCr clearance. There were no acute rejections after changes in immunosuppression. The safety of MMF was also analyzed and in only one patient was the drug stopped as a result of intractable diarrhea. These findings suggest that MMF is sufficiently powerful to allow a decrease/withdrawal of CsA without the burden of acute rejection in a pediatric population with CTN.

Prosthetic repair of incisional hernia in kidney transplant patients. A technique with onlay polypropylene mesh.

The employment of synthetic mesh for incisional hernia repair in kidney-transplanted patients is rarely reported in the present literature. Many authors believe that mesh employment in such conditions is not safe due to fear of mesh related complications. From 1965 through 1999, a total of 1685 kidney transplants were performed at our Kidney Transplant Unit and 19 patients developed eventrations in the kidney transplant incision, an incidence of 1.1%. From September 1996 eight of these patients had prosthetic repair of the abdominal wall with onlay polypropylene mesh. All patients were under immunosuppressive therapy with prednisone, ciclosporine and azathioprine. Mean age was 48.8 years, mean body mass index was 22.5 and mean number of previous abdominal operations was 2.5. A large polypropylene mesh (Marlex mesh) was fixed over the aponeurosis after primary closure of the aponeurotic borders, as an onlay graft. There was neither morbidity nor mortality associated to the surgical procedure. No recurrences or long-term complications associated with mesh employment were verified after a follow-up ranging from one year to three years. We concluded that prosthetic repair of incisional hernia in transplanted patients can be performed routinely.