Urinary tract infections beyond the early post-transplant period in pediatric renal graft recipients

Epidemiology and pathogen characteristics of infections following solid organ transplantation

Solid organ transplantation (SOT) recipients have a heightened risk for infection due to prolonged immunosuppressive drug use following transplant procedures. The occurrence of post-transplant infections is influenced not only by the transplanted organ type but also by varied factors. The kidney is the most common organ in SOT, followed by the liver, heart, and lung. This review aims to provide a comprehensive overview of the current epidemiological characteristics of infections after kidney, liver, heart, and lung transplantation, focusing on bacterial, fungal, and viral infections. The incidence and infection types demonstrated significant variability across different SOTs. Furthermore, this review attempts to elucidate the clinical characteristics of infections across patients following different SOTs and contribute to the development of individualized prevention strategies according to infection incidence, ultimately enhancing the quality of life of transplant recipients.

Evaluation of pediatric renal transplant recipients admitted to the intensive care unit: A retrospective cohort study

Background/Aim: The best course of treatment for children with end-stage kidney disease (ESKD) is renal transplantation (RT), but some pediatric RT recipients are admitted to an intensive care unit (ICU) post-transplant. In the early and late post-operative phases, clinical data about pediatric RT recipients who are admitted to ICU are available. In this study, we aimed to evaluate demographic features, main reasons, and outcomes of pediatric RT patients admitted to the ICU during the early and late post-operative phases. Methods: This study was a cohort study. We analyzed the medical records of pediatric RT recipients (<18 years of age) who were admitted to the ICU between May 30, 2011, and October 16, 2021, at our center, retrospectively. Patients ≥18 years of age and those without available data were excluded. We obtained the following data from ICU follow-up records and hospital medical records. The median (minimum-maximum) for continuous variables, frequencies, and percentages for categorical variables were used. The Chi-square test was used to compare categorical variables. We created graphs using percentages and frequencies to summarize the results. Results: Nineteen (16.5%) of the 115 pediatric patients who underwent RT were admitted to the ICU during the study period. Thirteen patients (68.4%) were male, and the mean age was 10.2 (4.9) years. Hypertension (21.2%) was the most common comorbidity. Eighteen (94.7%) received transplants from living donors. Cystic-hereditary-congenital disorders (42.1%, n=8) and congenital anomalies of the kidney and urinary tract (26.3%, n=5) were among the etiologies of ESKD. Ten patients (52.6%) were admitted to the ICU >6 months after transplantation. Epileptic seizure (n=6, 31.6%), respiratory failure (n=4, 21.1%), and cardiac diseases (n=2, 10.5%) were among the main reasons for ICU admission. During ICU follow-up, invasive mechanical ventilation was needed for five patients (26.3%), and renal replacement treatment was needed for four patients (21.1%). The mean length of ICU was 12.4 (28.5), and the mean hospital stay was 25.8 (29.4) days. The ICU and hospital survival rates were 78.9% and 97%, respectively, while 3.5% was the hospital mortality rate. Hemorrhagic cerebrovascular disease, acute hepatic failure, and cardiogenic shock secondary to pericardiocentesis were the causes of death in the ICU. Conclusion: Patients mostly had ICU admissions because of epileptic seizures and acute respiratory failure. A multidisciplinary approach involving pediatric nephrologists, transplant surgeons, and an intensive care team successfully manages pediatric RT recipients admitted to the intensive care unit.

Emergency Department Utilization and Serious Bacterial Infection Rates in Children With Renal Transplants

OBJECTIVES

Emergency department (ED) visits by children with solid organ transplants have increased significantly. Our objectives were to describe the common complaints, diagnosis, types, and rates of serious bacterial infection (SBI) in children with renal transplant (RT) who present to the hospital.

METHODS

We conducted a retrospective study from 2012 to 2016 of RT children up to 18 years who presented to the ED or were directly admitted. We excluded patients who presented for a procedure. We collected demographics, transplant type, immunosuppressive data, chief complaints, diagnostic testing with results, interventions performed, and final diagnosis.

RESULTS

We analyzed 131 visits in 29 patients during the study period. Most common chief complaints were infectious (34.4%) and gastrointestinal (26%). Infection was proven in 42.0% of visits with only 3.1% being organ rejection. Serious bacterial infection was diagnosed in 34 visits (26.0%) with urinary tract infection (UTI) being the most common (20.6%). Of the 33 visits for fever, SBI occurred in 16 (48.5%) patients with the most common SBI being UTI 10 (30.3%). Bacteremia occurred in 1 patient and hypotension in 4 patients. Antibiotic administration was the most common intervention performed (78; 59.5%). Significant interventions were uncommon (2 patients). Logistic regression revealed no factors to be associated with SBI.

CONCLUSIONS

Our cohort of children with RT presented most commonly with infections to the hospital with UTI being the most common SBI. Bacteremia and significant interventions were rare. Future studies are needed to identify subgroups of low-risk pediatric RT patients who can possibly be safely discharged home from the ED.

Pediatric renal transplantation; 10 years experience

Objectives

Although renal transplantation (RT) is the first treatment option for children with end-stage renal failure, the number of transplanted chil- dren remains low compared to adults. Experience of the individual pediatric transplant center is very important in the prognosis of pediatric transplant recipients. In this study, our pediatric RT experience was presented.

Material and Methods

We retrospectively analyzed the data of 27 patients who had RT in our clinic between April 2009 and April 2019.

Results

Fifteen of the patients were males, and mean age of all patients was 12.36 ± 4.18 years (range 4-17 years). The most frequent etiology for end- stage renal disease (ESRD) was vesicourethral reflux. Eighteen (66.7%) of the transplanted kidneys came from cadaveric donors and 9 (33.3%) from live donors. One patient had preemptive RT and one patient had a re-RT. Twenty-two patients were on peritoneal dialysis program and four patients were on hemodialysis program. Mean dialysis time before transplantation was 29 (3-104) months. Bleeding was the most common surgical complication. Delayed graft function developed in four patients, and all of their grafts were from cadaveric donors. Rejection developed in 12 of our patients, graft loss was observed in only four of them. Considering all patients, graft survival rates were 100% in the 1st and 3rd years, and 92% in the 5th year.

Conclusion

Pediatric RT program is difficult to establish, maintain and develop. Complications after transplantation are not uncommon; therefore, early detection and appropriate management are needed. Strategies are still needed to increase post-transplant success.

Pediatric kidney transplantation in Egypt: Results of 10-year single-center experience

Pediatric kidney transplantation is a multidisciplinary therapy that needs special consideration and experience. In this study, we aimed to present CUCH experience; over a 10-year period, as a specialized center of kidney transplantation in children. We studied 148 transplantations performed at a single center from 2009 to 2018. Pretransplant and follow-up data were collected and graft/patient survival rates were evaluated. A total of 48 patients developed at least one rejection episode during 688 patient-years of follow-up. Infections, recurrence of original disease, and malignancy were the most important encountered medical complications (20%, 2%, and 1.4%, respectively). One-year patient survival was 94.1%, while graft and patient survival was 91.9%. Graft/patient survival at 5, 7, and 9 years was 90%, 77%, and 58%, respectively. Infections were the main cause (69%) of mortality. Death with a functioning graft and CR were the main causes of graft loss (48% and 33%, respectively). Pediatric kidney transplantation in Egypt is still a challenging yet successful experience. Rejections and infections are the most frequent complications. Short-term outcomes surpass long-term ones and graft survival rates are similar to the international standard.

Infectious disease risks in pediatric renal transplantation

Renal transplantation is a vital treatment option in children with ESRD with more than 10,000 pediatric kidney transplants and survival rates of greater than 80% at 10 years post-transplant in the USA alone. Despite these advances, infection remains a significant cause of morbidity in pediatric recipients. Screening potential organ donors and recipients is imperative to identify and mitigate infectious risks in the transplant patient. Despite the unique risks of each patient, the timing of many infections post-transplant is predictable. In early post-transplant infections (within 30 days), bacterial and fungal pathogens predominate with donor-derived events and nosocomial infections. In the intermediate period (31-180 days after transplant), latent infections from donor organs, such as EBV and CMV, develop. Late infections occurring > 180 days after the transplant can be due to latent pathogens or community-acquired organisms. Approaching an infectious evaluation in a pediatric kidney recipient requires finesse to diagnose and treat this vulnerable population in a timely manner. The following article highlights the most relevant and common infections including clinical manifestations, risk factors, diagnostic techniques, and treatment options.

Risk factors for urological complications following living donor renal transplantation in children

The aim of this study was to detect possible risk factors for UC and UTI following pediatric renal Tx and effect of these complications on outcome. One hundred and eight children who underwent living donor Tx between 2009 and 2015 were retrospectively included. Extraperitoneal approach was used with stented tunneled extravesical procedure. Mean recipient age was 9.89 ± 3.46 years while mean weight was 25.22 ± 10.43 kg. Seventy-three (67.6%) recipients were boys while 92 (85.2%) were related to donors. Urological causes of ESRD were present in 33 (30.6%) recipients (14 [13%] posterior urethral valve, 16 [14.8%] VUR, and 3 [2.8%] neurogenic bladder). Augmentation ileocystoplasty was performed in 9 (8.3%) patients. Mean follow-up was 39.3 ± 17.33 months. UC were detected in 10 (9.3%) children (leakage 4 [3.7%], obstruction 3 [2.8%], and VUR 3 [2.8%]) while UTIs were reported in 40 (37%) children. After logistic regression analysis, UC were significantly higher in children with cystoplasty (44.4% vs 6.1%; P = .001). UTIs were significantly higher in girls (51.4% vs 30.1%; P = .001) and in children with urological causes of ESRD (51.5% vs 30.7%; P = .049). UC and UTI were not significantly associated with increased graft loss or mortality. UC were significantly higher in children with cystoplasty while UTIs were significantly higher in girls and children with urological causes of ESRD. Presence of UC did not affect the rate of graft loss or mortality due to its early detection and proper management.

Febrile urinary tract infection after pediatric kidney transplantation: a multicenter, prospective observational study

BACKGROUND

Febrile urinary tract infections (fUTIs) are common after kidney transplantation (KTx); however, prospective data in a multicenter pediatric cohort are lacking. We designed a prospective registry to record data on fUTI before and after pediatric KTx.

METHODS

Ninety-eight children (58 boys and 40 girls) ≤ 18 years from 14 mid-European centers received a kidney transplant and completed a 2-year follow-up.

RESULTS

Posttransplant, 38.7% of patients had at least one fUTI compared with 21.4% before KTx (p = 0.002). Before KTx, fUTI was more frequent in patients with congenital anomalies of kidneys and urinary tract (CAKUT) vs. patients without (38% vs. 12%; p = 0.005). After KTx, fUTI were equally frequent in both groups (48.7% vs. 32.2%; p = 0.14). First fUTI posttransplant occurred earlier in boys compared with girls: median range 4 vs. 13.5 years (p = 0.002). Graft function worsened (p < 0.001) during fUTI, but no difference was recorded after 2 years. At least one recurrence of fUTI was encountered in 58%.

CONCLUSION

This prospective study confirms a high incidence of fUTI after pediatric KTx, which is not restricted to patients with CAKUT; fUTIs have a negative impact on graft function during the infectious episode but not on 2-year graft outcome.

Outcomes of living donor renal transplantation in children with lower urinary tract dysfunction: a comparative retrospective study

OBJECTIVES

To compare outcomes of renal transplantation (RTx) in children with end-stage renal disease (ESRD) resulting from lower urinary tract dysfunction (LUTD) vs other causes.

PATIENTS AND METHODS

A database of children (<18 years old) who underwent RTx between May 2008 and April 2012 was reviewed. Patients were divided into those with LUTD (group A, n = 29) and those with other causes of ESRD (group B, n = 74). RTx was performed after achieving low intravesical pressure (<30 cmH2 O) with adequate bladder capacity and drainage. The groups were compared using Student's t-test, Mann-Whitney, chi-squared or exact tests. Graft survival rates (GSRs) were evaluated using Kaplan-Meier curves and the log-rank test.

RESULTS

The mean ± sd (range) age of the study cohort was 5.05 ± 12.4 (2.2-18) years. Causes of LUTD were posterior urethral valve (PUV; 41.4%), vesico-ureteric reflux (VUR; 37.9%), neurogenic bladder (10.3%), prune belly syndrome (3.4%), obstructive megaureter (3.4%) and urethral stricture disease (3.4%). There was no significant difference in age, dialysis duration or donor type. In group A, 25 of the 29 patients (86.2%) underwent ≥1 surgery to optimize the urinary tract for allograft. Pretransplant nephrectomy was performed in 15 of the 29 patients (51.7%), PUV ablation in nine patients (31%) and ileocystoplasty in four patients (13.7%). The mean ± sd follow-up was 4.52 ± 1.55 and 4.07 ± 1.27 years in groups A and B, respectively. There was no significant difference in creatinine and eGFR between the groups at different points of follow-up. The GSRs at the end of the study were 93.1 and 91.1% in groups A and B, respectively (P = 1.00). According to Kaplan-Meier survival curves, there was no significant difference in the GSR between the groups using the log-rank test (P = 0.503). No graft was lost as a result of urological complications. In group B, one child died from septicaemia. The rate of urinary tract infections was 24 and 12% in groups A and B, respectively, but was not significant. No significant difference was found between the groups with regard to the incidence of post-transplantation hydronephrosis. Of the 22 patients who had hydronephrosis after transplantation, three were complicated by UTI. Injection of bulking agents was required in two patients for treatment of grade 3 VUR. In the third patient, augmentation cystoplasty was needed.

CONCLUSION

Acceptable graft function, survival and UTI rates can be achieved in children with ESRD attributable to LUTD. Thorough assessment and optimization of LUT, together with close follow-up, are key for successful RTx.

Non-viral infections in children after renal transplantation

Renal transplantation has long been recognised as the gold standard treatment for children with end-stage renal failure. There has been an improvement over the years in patient and renal allograft survival because of improved immunosuppression, surgical techniques and living kidney donation. Despite reduced acute allograft rejection rates, non-viral infections continue to be a serious complication for paediatric renal transplant recipients (RTR). The risk of infections in RTR is determined by the pre-transplantation immunisation status, post-transplant exposure to potential pathogens and the amount of immunosuppression. The greatest risk of life-threatening and Cytomegalovirus infections is during the first 6 months post-transplant owing to a high immunosuppressive burden. The potential sources of bacterial infections are donor derived, transplant medium fluid, peritoneal and haemodialysis catheter and transplant ureteric stent. Urinary tract infections are frequent in patients with lower urinary tract dysfunction and can result in renal allograft damage. This review outlines the incidence, timing, risk factors, prevention and treatment of non-viral infections in paediatric RTR by critically reviewing current immunosuppressive regimens, their risk-benefit ratio in order to optimise renal allograft survival with reduced rates of rejection and infectious complications.

Urinary tract infections in pediatric renal transplant recipients--a two center risk factors study

UTI are common in renal Tx recipients and may significantly impact on the graft function. The aim of our study was to evaluate the prevalence, risk factors, and significance of UTI in Tx children. We performed a retrospective cross-sectional study of 76 Tx patients, median age at Tx was 13.4 yr. Twenty-one of 76 (28%) patients developed at least one UTI during the mean follow-up time of 3.3 +/- 2.0 yr post-Tx. The first UTI occurred at a median of 160 days post-Tx. The RR of having UTI was significantly higher in patients with the primary diagnosis of obstructive uropathy (RR = 2.6, 95th CI = 1.1-6.0, p = 0.032), history of PN pre Tx (RR = 2.7, 95th CI = 1.3-5.4, p = 0.009) and pre Tx VUR (RR = 2.2, 95th CI = 1.1-4.5, p = 0.045). These three factors also significantly decreased the infection-free survival time to the first UTI. Most UTI caused reversible acute allograft dysfunction, but the long-term graft function could not be reliably assessed with SCr. In conclusion, UTI occurred in 28% of pediatric Tx recipients, mostly during the first year post-Tx despite antibiotic prophylaxis. The diagnosis of obstructive uropathy, history of UTI and VUR prior to Tx were significant risk factors.

Urinary tract infections in children after renal transplantation

Urinary tract infections (UTI) after pediatric kidney transplantation (KTX) are an important clinical problem and occur in 15-33% of patients. Febrile UTI, whether occurring in the transplanted kidney or the native kidney, should be differentiated from afebrile UTI. The latter may cause significant morbidity and is usually associated with acute graft dysfunction. Risk factors for (febrile) UTI include anatomical, functional, and demographic factors as well as baseline immunosuppression and foreign material, such as catheters and stents. Meticulous surveillance, diagnosis, and treatment of UTI is important to minimize acute morbidity and compromise of long-term graft function. In febrile UTI, parenteral antibiotics are usually indicated, although controlled data are not available. As most data concerning UTI have been accumulated retrospectively, future prospective studies have to be performed to clarify pathogenetic mechanisms and risk factors, improve prophylaxis and treatment, and ultimately optimize long-term renal graft survival.

Urinary Tract Infections and Bladder Dysfunction After Renal Transplantation in Children

PURPOSE

Urinary tract infection remains a major cause of morbidity in pediatric renal transplant recipients. In otherwise healthy children bladder dysfunction increases the susceptibility to urinary tract infection. The aims of this study were to determine whether bladder dysfunction affects the incidence of urinary tract infection after renal transplantation, and to assess the impact of recurrent urinary tract infections on graft function.

MATERIALS AND METHODS

We evaluated bladder function with a questionnaire, uroflowmetry and bladder ultrasound, and renal function with clearance of inulin or iohexol (glomerular filtration rate) in 68 recipients of renal transplants 5 to 20 years old, at 1 to 15 years after transplantation, with and without recurrent urinary tract infections.

RESULTS

Bladder dysfunction was equally common in children with and without recurrent urinary tract infections (68% vs 74%, not significant). Therefore, it had no effect on the incidence of recurrent urinary tract infections. Graft function deteriorated at a faster rate in patients with recurrent urinary tract infections than in those without (mean glomerular filtration rate 45 vs 57 ml per minute per 1.73 m(2) at 4 years after transplantation, p=0.02).

CONCLUSIONS

Bladder dysfunction did not predispose patients to recurrent urinary tract infections. Graft function declined with time in all patients but the rate of deterioration was faster in the group with recurrent urinary tract infections.

[Kidney transplantation in childhood and adolescence. Management of functional disorders and follow-up care of the kidney transplant recipient]

The causes that lead to terminal renal failure in children and adolescents and subsequently require dialysis are different from those in adults. Moreover, children with a functioning kidney transplant evidence an approximately fourfold higher survival probability than children on dialysis. This contribution describes kidney transplantation in light of the specific features for this age group.

Effects of Urinary Tract Infection on Outcomes after Renal Transplantation in Children

Urinary tract infection (UTI) is the most common infection after kidney transplantation. A previous analysis showed that late (>6 mo after transplantation) UTI is associated with earlier graft loss in adults. It was hypothesized that children who are younger than 18 yr would be at higher risk to develop UTI and develop graft loss after both early and late UTI. The US Renal Data System database was analyzed from 1996 to 2000 for Medicare claims (composite of inpatient and outpatient) for UTI up to 36 mo after transplantation. SPSS software and Cox regression models were used to determine association of UTI and age after adjustment for covariates. Early UTI was defined as occurring <6 mo after transplantation, and late UTI was defined as occurring > or =6 mo after transplantation. The risk for graft loss after early UTI was elevated in all children (adjusted hazard ratio [AHR] 5.47; 95% confidence interval [CI] 1.93 to 15.4; P < 0.001) but not after late UTI (AHR 2.09; 95% CI 0.56 to 7.80; P = 0.27). Risk for posttransplantation death was not increased significantly after either early UTI (AHR 1.23; 95% CI 0.37 to 4.08) or late UTI (relative risk 2.22; 95% CI 0.90 to 5.44). Boys aged 2 to 5 (versus age 13 to <18 years) were at significantly higher risk for UTI. In girls, only those in the youngest age category (0 to 1) had higher risk for UTI. Children are at greater risk for graft loss after early but not necessarily late UTI. UTI was not an independent predictor of death in this population.

Dysfunction of lower urinary tract in renal transplant children with nephrologic disease

OBJECTIVES

To investigate the relationship between dysfunction of the lower urinary tract after renal transplantation and renal transplant function in children with an underlying nephrologic disease.

METHODS

The research group consisted of 21 renal transplant children (12 girls and 9 boys, mean age 13.5 years, range 6 to 18) with an underlying nephrologic disease. To indicate renal transplant function, the calculated creatinine clearance rate (Ccr) according to Schwartz was used. The Ccr was measured at two points, 2 months after transplantation and at the moment of study. The average graft age was 34 months (range 5 to 85). The data on dysfunction of the lower urinary tract were gathered using a written questionnaire, frequency volume chart, free uroflowmetry, transabdominal ultrasonography, and medical records. To determine the relationship between the symptoms of dysfunction of the lower urinary tract and Ccr at the moment of study, we computed bivariate correlations and performed multivariate regression analyses in which the associations were studied while controlling for the Ccr 2 months after transplantation and graft age.

RESULTS

A sensation of incomplete emptying (P = 0.03), postvoid residual urine volume (P = 0.06), and urinary tract infection (P = 0.004) correlated negatively with the Ccr at the moment of study. These effects remained present (P = 0.07, P = 0.03, and P = 0.003, respectively) while controlling for graft age and the Ccr at 2 months after transplantation in the regression analysis.

CONCLUSIONS

The results of our study have shown that a postvoid residual urine volume and urinary tract infections after renal transplantation may result in renal transplant deterioration in children with an underlying nephrologic disease.