Donors with small asymptomatic kidney stones have been increasingly accepted because of organ shortages and advances in endoscopic urology. This study aims to evaluate and compare long-term living-donor kidney transplant outcomes following ex vivo surgical removal versus conservative management of donors' gifted asymptomatic stones.

Between January 2007 and December 2021, 119 kidney transplant recipients received stone-bearing kidneys, divided into the removal group (N = 63) and observation group (N = 56). We evaluated posttransplant stone events, urinary infections, kidney function, delayed graft function, length of hospital stay, and survival outcomes.

After a median follow-up of 75.5 mo, the removal group had a 10.9% lower absolute incidence of stone events (7/56 [12.5%] versus 1/63 [1.6%]; hazard ratio, 0.08; 95% confidence interval, 0.01-0.77) and a 14.3% lower absolute incidence of urinary infections (16/56 [28.6%] versus 9/63 [14.3%]; hazard ratio, 0.42; 95% confidence interval, 0.19-0.95) than the observation group. The removal group also showed superior kidney graft function. The 2 groups had comparable length of hospital stay (11.0 versus 12.0 d; P  = 0.297) and exhibited similar delayed graft function incidence (1/56 [1.8%] versus 2/63 [3.2%]; P  = 1.000) and urinary stricture incidence (1/56 [1.8%] versus 3/63 [4.8%]; P  = 0.621). Graft survival ( P  = 0.350) and patient survival ( P  = 0.260) were comparable between 2 groups. Subgroup analyses in recipients who received kidneys with stones <4 mm also reported similar results.

Ex vivo surgical removal might outperform conservative management for donors' gifted asymptomatic kidney stones, improving long-term transplant outcomes and reducing stone events without increasing perioperative complications, even for stones <4 mm.

This review addresses the management of urolithiasis in renal transplant recipients, a notably vulnerable group due to the unique anatomical and physiological alterations of the transplanted organ. The prevalence of nephrolithiasis in these patients varies between 0.1% and 6.3%, with a significant impact on graft longevity and function. Surgical access complications due to the renal graft's position on the iliac vessels and the variety of urinary anastomoses complicate the treatment approaches. This study evaluates the effectiveness and outcomes of percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS), two primary minimally invasive strategies for managing graft stones. Through a narrative review using the PubMed and EMBASE databases, it was found that PCNL offers high stone-free rates especially beneficial for large stones, whereas URS provides a less invasive option with a lower risk of complications for small stones. Both techniques require tailored approaches based on stone composition-mostly calcium oxalate-and specific patient anatomical factors. This review underscores the importance of early diagnosis, appropriate treatment selection, and continuous post-treatment monitoring to mitigate risks and promote long-term renal function in transplant recipients.

Introduction and Objective: Renal transplantation is the treatment for end-stage renal disease that offers better quality of life and survival. Among the possible complications that might affect allografts, urolithiasis might have severe consequences, causing acute kidney injury (AKI) or septic events in immunocompromised patients. Allograft stones might be treated with percutaneous nephrolithotomy (PCNL). The aim of this Cochrane style review was to assess the safety and efficacy of PCNL in patients with renal transplant. Methods: A comprehensive search in the literature was performed including articles between July 1982 and June 2023, with only English original articles selected for this review. Results: The final review encompassed nine articles (108 patients). The mean age was 46.4 ± 8.7 years, with a male:female ratio of 54:44. The average time from transplantation to urolithiasis onset was 47.54 ± 23.9 months. Predominant symptoms upon presentation were AKI (32.3%), followed by urinary tract infection and fever (24.2%), and oliguria (12.9%). The mean stone size was 20.1 ± 7.3 mm, with stones located in the calices or pelvis (41%), ureteropelvic junction (23.1%), or proximal ureter (28.2%). PCNL (22F-30F) was more frequently performed than mini-PCNLs (16F-20F) (52.4% vs 47.6%). Puncture was guided by ultrasound (42.9%), fluoroscopy (14.3%), or both (42.9%). The stone-free rate (SFR) and complication rates were 92.95% (range: 77%-100%) and 5.5%, respectively, with only one major complication reported. Postoperatively, a ureteral stent and nephrostomy were commonly placed in 47%, with four patients needing a second look PCNL. During an average follow-up of 32.5 months, the recurrence rate was 3.7% (4/108), and the mean creatinine level was 1.37 ± 0.28 mg/dL. Conclusions: PCNL remains a safe and effective option in de novo allograft urolithiasis, allowing to treat large stones in one-step surgery. A good SFR is achieved with a low risk of minor complications. These patients should be treated in an endourology center in conjunction with the renal or transplant team.

The lifetime incidence of kidney stones is 6%-12% in the general population. Nephrolithiasis is a known cause of acute and chronic kidney injury, mediated via obstructive uropathy or crystal-induced nephropathy, and several modifiable and non-modifiable genetic and lifestyle causes have been described. Evidence for epidemiology and management of nephrolithiasis after kidney transplantation is limited by a low number of publications, small study sizes and short observational periods. Denervation of the kidney and ureter graft greatly reduces symptomatology of kidney stones in transplant recipients, which may contribute to a considerable underdiagnosis. Thus, reported prevalence rates of 1%-2% after kidney transplantation and the lack of adverse effects on allograft function and survival should be interpreted with caution. In this narrative review we summarize current state-of-the-art knowledge regarding epidemiology, clinical presentation, diagnosis, prevention and therapy of nephrolithiasis after kidney transplantation, including management of asymptomatic stone disease in kidney donors. Our aim is to strengthen clinical nephrologists who treat kidney transplant recipients in informed decision-making regarding management of kidney stones. Available evidence, supporting both surgical and medical treatment and prevention of kidney stones, is presented and critically discussed. The specific anatomy of the transplanted kidney and urinary tract requires deviation from established interventional approaches for nephrolithiasis in native kidneys. Also, pharmacological and lifestyle changes may need adaptation to the specific situation of kidney transplant recipients. Finally, we point out current knowledge gaps and the need for additional evidence from future studies.

Lithiasis in renal graft recipients might be a dangerous condition with a potential risk of organ function impairment.

A systematic literature search was conducted through February 2023. The primary objective was to assess the incidence of lithiasis in kidney transplant (KT) recipients. The secondary objective was to assess the timing of stone formation, localization and composition of stones, possible treatment options, and the incidence of graft loss.

A total of 41 non-randomized studies comprising 699 patients met our inclusion criteria. The age at lithiasis diagnosis ranged between 29-53 years. Incidence of urolithiasis ranged from 0.1-6.3%, usually diagnosed after 12 months from KT. Most of the stones were diagnosed in the calyces or in the pelvis. Calcium oxalate composition was the most frequent. Different treatment strategies were considered, namely active surveillance, ureteroscopy, percutaneous/combined approach, or open surgery. 15.73% of patients were submitted to extracorporeal shock wave lithotripsy (ESWL), while 26.75% underwent endoscopic lithotripsy or stone extraction. 18.03% of patients underwent percutaneous nephrolithotomy whilst 3.14% to a combined approach. Surgical lithotomy was performed in 5.01% of the cases. Global stone-free rate was around 80%.

Lithiasis in kidney transplant is a rare condition usually diagnosed after one year after surgery and mostly located in the calyces and renal pelvis, more frequently of calcium oxalate composition. Each of the active treatments is associated with good results in terms of stone-free rate, thus the surgical technique should be chosen according to the patient's characteristics and surgeon preferences.

Kidney stone disease is common and can lead to complications such as AKI, urinary tract obstruction, and urosepsis. In kidney transplant recipients, complications from kidney stone events can also lead to rejection and allograft failure. There is limited information on the incidence of kidney stone events in transplant recipients.

We identified 83,535 patients from the United States Renal Data System who received their first kidney transplant between January 1, 2007, and December 31, 2018. We examined the incidence of kidney stone events and identified risk factors associated with a kidney stone event in the first 3 years after transplantation.

We found 1436 patients (1.7%) who were diagnosed with a kidney stone in the 3 years after kidney transplant. The unadjusted incidence rate for a kidney stone event was 7.8 per 1000 person-years. The median time from transplant to a kidney stone diagnosis was 0.61 (25%-75% range 0.19-1.46) years. Patients with a history of kidney stones were at greatest risk of a kidney stone event after transplant (hazard ratio [HR], 4.65; 95% confidence interval [CI], 3.82 to 5.65). Other notable risk factors included a diagnosis of gout (HR, 1.53; 95% CI, 1.31 to 1.80), hypertension (HR, 1.29; 95% CI, 1.00 to 1.66), and a dialysis of vintage of ≥9 years (HR, 1.48; 95% CI, 1.18 to 1.86; ref vintage ≤2.5 years).

Approximately 2% of kidney transplant recipients were diagnosed with a kidney stone in the 3 years after kidney transplant. Risk factors of a kidney stone event include a history of kidney stones and longer dialysis vintage.

Although urolithiasis is relatively common in the general population, there is limited information on this condition available in the pregnant population. The objectives of this study are to identify the incidence of urolithiasis in pregnancy, as well as to compare maternal and fetal outcomes associated with urolithiasis in pregnancy.

Using the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database from the United States, a population-based retrospective cohort study consisting of pregnant women who delivered between 1999 and 2015 was conducted. ICD-9-CM code 592.X was used to identify pregnant women with urolithiasis within the cohort, with pregnant women without urolithiasis forming the comparison group. Unconditional logistic regression models were used to estimate the associations between urolithiasis in pregnancy and maternal and neonatal outcomes, while adjusting for baseline maternal characteristics.

A cohort of 13,792,544 pregnant women was identified, of which 11,528 had a urolithiasis-related admission during pregnancy, for an overall incidence of 8.3 per 10,000 pregnancies. Women with urolithiasis had a greater risk of developing preeclampsia/eclampsia, OR 1.35(95% CI 1.24-1.47), gestational diabetes, 1.29(1.20-1.30), abruptio placenta, 1.41(1.22-1.64), placenta previa, 1.55(1.27-1.90), pyelonephritis, 88.87(81.69-96.69), venous thromboembolism, 1.65(1.23-2.22), and more likely to deliver by cesarean, 1.20(1.15-1.25). As well, maternal death was more common among these women, 2.85(1.07-7.60). Congenital anomalies, 2.84(2.43-3.31) and prematurity, 1.92(1.82-2.03) were more commonly found among babies born to women with urolithiasis.

Although the mechanism is unclear, women with urolithiasis in pregnancy have an increased risk of adverse pregnancy and newborn outcomes.

To evaluate the effect of pregnancy on the clinical presentation, inpatient procedure rates, and length of hospital stay, on women with urolithiasis.

We carried out a matched cohort study using the United States' Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database from 1999 to 2015. Pregnant women with urolithiasis were compared to age-matched non-pregnant women (1:1) with urolithiasis. Baseline clinical characteristics were compared between the two cohorts and the effect of pregnancy on select inpatient procedural and clinical outcomes was evaluated using conditional logistic regression models.

There were 42,113 pregnant patients diagnosed with urolithiasis during the study period. It was observed that pregnant patients were less likely to present with classic clinical symptoms of urinary tract stones, such as flank pain, OR 0.63, 95% CI 0.56-0.70, and fever, 0.22 (0.16-0.30), but tended to have longer hospital stays. The pregnant patients were less commonly affected by infectious conditions, namely urinary tract infections, 0.56 (0.53-0.59), sepsis, 0.17 (0.14-0.20), and pyelonephritis, 0.34 (0.36-0.44). Invasive and surgical procedures were less commonly performed in pregnant women.

Pregnant women admitted with urolithiasis appear to be less symptomatic with fewer interventions and complications than non-pregnant women with urolithiasis.

To define guidelines for the management of kidney stones in kidney transplant (KTx) donor or recipients.

Following a systematic approach, a review of the literature (Medline) was conducted by the CTAFU to report kidney stone epidemiology, diagnosis and management in KTx donors and recipients with the corresponding level of evidence.

Prevalence of kidney stones in deceased donor is unknown but reaches 9.3% in living donors in industrialized countries. Except in Maastrich 2 donors, diagnosis is done on systematic pre-donation CT scan according to standard french procedure. No prospective study has compared therapeutic strategies available for the management of kidney stones in KTx donor: ureteroscopy or an extra corporeal lithotripsy in case of living donor prior to donation, ex vivo approach (pyelotomy or ureteroscopy), ureterocopy in the KTx recipient or surveillance. De novo kidney stones result from a lithogenesis process to be identified and treated in order to avoid recurrences. The context of solitary functional kidney renders the prevention of recurrence of great importance. Diagnosis is suspected when identification of a renal graft dysfunction, hematuria or urinary tract infection with renal pelvis dilatation. Stone size and location are determined by computed tomography. There are no prospective, controlled studies on kidney stone management in the KTx. The therapeutic strategies are similar to standard management in general population.

These French recommendations should contribute to improve kidney stones management in KTx donor and recipients.

Renal transplant lithiasis is a rather unusual disease, and the recurrence of lithiasis presents a challenging situation.

We retrospectively analyzed the medical history of one patient who suffered renal transplant lithiasis twice, reviewed the relevant literature, and summarized the characteristics of this disease.

We retrieved 29 relevant studies with an incidence of 0.34 to 3.26% for renal transplant lithiasis. The summarized incidence was 0.52%, and the recurrence rate was 0.082%. The mean interval after transplantation was 33.43 ± 56.70 mo. Most of the patients (28.90%) were asymptomatic. The management included percutaneous nephrolithotripsy (PCNL, 22.10%), ureteroscope (URS, 22.65%), extracorporeal shockwave lithotripsy (ESWL, 18.60%) and conservative treatment (17.13%). In our case, the patient suffered from renal transplant lithiasis at 6 years posttransplantation, and the lithiasis recurred 16 months later. He presented oliguria, infection or acute renal failure (ARF) during the two attacks but without pain. PCNL along with URS and holmium laser lithotripsy were performed. The patient recovered well after surgery, except for a 3 mm residual stone in the calyx after the second surgery. He had normal renal function without any symptoms and was discharged with oral anticalculus drugs and strict follow-up at the clinic. Fortunately, the calculus passed spontaneously about 1 month later.

Due to the lack of specific symptoms in the early stage, patients with renal transplant lithiasis may have delayed diagnosis and present ARF. Minimally invasive treatment is optimal, and the combined usage of two or more procedures is beneficial for patients. After surgery, taking anticalculus drugs, correcting metabolic disorders and avoiding UIT are key measures to prevent the recurrence of lithiasis.

Urolithiasis in renal transplant (RTx) recipients is a potential cause of allograft loss if obstruction is untreated. It is not clear if paediatric transplant recipients are following the global trend for increased prevalence of urolithiasis over time.

A retrospective chart review was undertaken to evaluate the frequency, risk factors and characteristics of post-RTx urolithiasis over two decades (1995-2016), in a tertiary Australian paediatric hospital.

Stones were diagnosed in 8 of 142 (5.6%) recipients, 6 of whom were transplanted in the latter decade. All patients were male, with a median age 4.9 years and median weight 11.8 kg. Presentation was with haematuria (n=4), pain (n=2), dysuria (n=2), stone passage (n=1) and asymptomatic (n=1). Time to presentation was bimodal; three stones were identified in the initial 3 months post RTx and the remainder after 31-53 months. Two stones were in association with retained suture material and two patients had recurrent urinary tract infections. The average stone size was 8.4 mm. Five stones were analysed; all contained calcium oxalate, three were mixed, including one with uric acid. Five (83.3%) children had hypercalciuria but none had hypercalcaemia. Cystolithotripsy was the the most common treatment (n=5), in combination with citrate supplementation. No graft was lost due to stones.

Calculi occur with increasing frequency after renal transplantation. Clinicians need a high index of suspicion as symptoms may be atypical in this population. The cause for the increased frequency of stones in transplant recipients is not clear but is in keeping with the increase seen in the general paediatric population.

We report on the long-term follow-up of managing allograft stones at a single tertiary referral institution and review the relevant literature.

A retrospective analysis of renal allograft recipient charts was performed to identify patients who developed allograft lithiasis between 1974 and 2009. Patient and stone characteristics, diagnoses, treatments, and outcomes were described.

Sixteen patients developed 22 stones after a median follow-up of 170 months (range, 51-351 mo). The mean (standard deviation) and median diameter of the stones were 13.8 (8.5) mm and 11 mm. Among these, 3 stones were treated conservatively, 3 by shock-wave lithotripsy, and 7 by cystolitholapaxy. Seven patients underwent percutaneous treatment in the form of percutaneous nephrostomy tube fixation and spontaneous passage of stone (1 stone), shock-wave lithotripsy (1 stone), antegrade stenting (1 stone), and percutaneous nephrolithotomy (6 stones). All patients were stone free after treatment, except for 2 patients whose stones were stable and peripheral on long-term follow-up.

Allograft lithiasis requires a multimodal treatment tailored according to stone and graft characteristics. Protocols regarding spontaneous passage can be adopted if there is no harm to the graft and the patient is compliant. Careful attention to the anatomy during percutaneous nephrostomy tube placement is mandatory to avoid intestinal loop injury. A more attentive follow-up is required for early stone management.

To report epidemiology and characteristics of urinary lithiasis and its management in kidney allograft at the time of organ procurement or after kidney transplantation.

An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords (MESH): urinary lithiasis, stone, kidney transplantation. Publications obtained were selected based on methodology, language, date of publication (last 10 years) and relevance. Prospective and retrospective studies, in English or French, review articles; meta-analysis and guidelines were selected and analyzed. This search found 58 articles. After reading, 37 were included in the text based on their relevance.

Frequency of urinary lithiasis in renal transplant recipient is similar to those observed in the general population. Generally, urinary lithiasis of the graft is asymptomatic because of renal denervation after organ procurement and transplantation. Nevertheless, this situation may be at high risk due to the immunosuppressed state of the recipient with a unique functioning kidney. Most of the time, the diagnosis is incidental during routine post-transplantation follow-up. Management of urolithiasis in renal transplant recipient is similar to that performed in general population.

Due to its potential severity in transplanted immunosuppressed patients with a sole kidney, urolithiasis requires expert urological management.

Urological complications after kidney transplantation can cause a major reduction in renal function. Surgical complications like urinary leakage and ureteral obstruction need to be solved by a specialist in the field of endourological procedures and open surgical interventions. The article summarizes this and other common urological problems after kidney transplantation.

Analysing the data available in the literature, contemporary methods of treatment of nephrolithiasis are limited to the methods of minimally invasive percutaneous nephrolithotomy (PCNL) and ureterorenoscopic lithotripsy (URSL), not excluding their use in the presence of developmental abnormalities and kidney impairment only. Minimally invasive methods have become standard procedures. A complement to ineffective URSL and PCNL treatment is extracorporeal shock wave lithotripsy. This is confirmed by 30 years of observation in the only treatment of kidney calculi by Alken launched in 1981 and continued by Jones et al. Before the era of endoscopic procedures (PCNL and URSL) effectively removed the only deposits in the kidney in open operations. Minimally invasive treatments are recommended for patients with localized deposits in the pelvicalyceal system or solitary kidney ureter. They are recognized as safe and effective treatment in a solitary kidney in particular in patients who have already been operated on.

Renal transplant lithiasis represents a rather uncommon complication. Even rare, it can result in significant morbidity and a devastating loss of renal function if obstruction occurs. We present our experience with graft lithiasis in our series of renal transplantations and review the literature regarding the epidemiology, pathophysiology, and current therapeutic strategies in the management of renal transplant lithiasis.

In a retrospective analysis of a consecutive series of 1525 renal transplantations that were performed between January 1983 and March 2007, 7 patients were found to have allograft lithiasis. In five cases, the calculi were localized in the renal unit, and in two cases, in the ureter. A review in the English language was also performed of the Medline and PubMed databases using the keywords renal transplant lithiasis, donor-gifted lithiasis, and urological complications after kidney transplantation. Several retrospective studies regarding the incidence, etiology, as well as predisposing factors for graft lithiasis were reviewed. Data regarding the current therapeutic strategies for graft lithiasis were also evaluated, and outcomes were compared with the results of our series.

Most studies report a renal transplant lithiasis incidence of 0.4% to 1%. In our series, incidence of graft lithiasis was 0.46% (n=7). Of the seven patients, three were treated via percutaneous nephrolithotripsy (PCNL); in three patients, shockwave lithotripsy (SWL) was performed; and in a single case, spontaneous passage of a urinary calculus was observed. All patients are currently stone free but still remain under close urologic surveillance.

Renal transplant lithiasis requires vigilance, a high index of suspicion, prompt recognition, and management. Treatment protocols should mimic those for solitary kidneys. Minimally invasive techniques are available to remove graft calculi. Long-term follow-up is essential to determine the outcome, as well as to prevent recurrence.

We report a case of ureterolithiasis in a patient with an en bloc kidney transplantation, using extracorporeal shockwave lithotripsy (ESWL). The patient presented with asymptomatic macrohematuria. Computed tomography revealed a ureteral calculus just below the pyeloureteral junction with hydronephrosis of the medially positioned kidney. Took two sessions of ESWL were required for complete disintegration of the stone. At 3 years after successful treatment, the patient has an excellent functioning and stone-free graft.

To determine the feasibility, safety and efficacy of diagnostic and therapeutic ureteroscopy in renal allograft ureters.

We reviewed 1560 consecutive renal allografts performed between June 1989 and February 2002. A total of 28 patients (1.8%) had indications for an endoscopic procedure on the allograft ureter, as follows: obstructive ureteral calculi with a history of failed extracorporeal shock-wave lithotripsy, n=6; suspected ureteral stricture, n=3; upwardly migrated ureteral stents, n=9; and ureteral stricture at the ureteroneocystostomy site, n=10. Ureters were anastomosed to the bladder using the Leadbetter-Politano and Lich-Gregoire methods in six and 22 cases, respectively. Ureteroscopies were performed with a semi-rigid 9.8 F Wolf ureteroscope.

Identification of the ureteral orifice and insertion of a guide-wire into it was successful in 19 cases (68%). If we exclude the 10 patients with ureteral stricture, ureteroscopy was successful in 13/18 cases (72%). Four ureteral calculi (67%) were removed with the ureteroscope. Seven out of nine migrated stents (78%) were retrieved. Four patients with ureteral stricture at the ureteroneocystostomy site (40%) underwent successful ureteral dilatation and double-J ureteral catheters were also inserted. Diagnostic ureteroscopy was successful in all cases. Two complications (one urinary leakage and one symptomatic urinary tract infection) occurred and were managed conservatively.

Ureteral endoscopy is a safe and effective method for the management of urological complications after renal transplantation. This procedure can be considered the first choice, in preference to percutaneous and antegrade modalities.

Renal transplantation is increasingly performed in elderly patients, and the incidence of benign prostatic hyperplasia (BPH) increases with age. Anuric males on dialysis may have occult BPH and not develop obstructive symptoms until urine flow is restored after transplantation. If left untreated, BPH poses a risk for numerous complications, including acute urinary retention (AUR), recurrent urinary tract infections (UTI), and renal failure. The authors hypothesized that incident BPH after renal transplantation would adversely affect allograft survival.

Medicare claims for BPH, AUR, UTI, and prostate resection procedures (transurethral resection of the prostate; TURP) were assessed in a retrospective cohort of 23,622 adult male Medicare primary renal transplant recipients in the United States Renal Data System database who received transplants from 1 January 2000 to 31 July 2005 and followed through 31 December 2005.

The 3-yr incidence of BPH post-transplant was 9.7%. The incidences of AUR, UTI, and TURP after BPH diagnosis (up to 3 yr posttransplant) were 10.3%, 6.5%, and 7.3% respectively, and each was significantly associated with BPH. Cox regression analysis showed that recipient age per year, later year of transplant, and dialysis vintage were associated with incident BPH. Using Cox nonproportional hazards regression, BPH was significantly associated with renal allograft loss (including death).

BPH is common in males after renal transplant and is independently associated with AUR, UTI, and graft loss. It is unknown whether treatment of BPH, either medical or surgical, attenuates these risks.

Although some studies have described rehospitalization after transplantation, few have focused on risk factors and consequences of prolonged hospital stay. Our goal was to determine the causes, risk factors, and outcomes of prolonged rehospitalizations after renal transplantation.

In this retrospective study, 574 randomly selected rehospitalization records of kidney transplant recipients were reviewed from 1994 to 2006. Admissions were divided into group 1, prolonged stay (length of stay >14 days, n=149), and group II, short stay (length of stay <or=14 days, n=425). Demographic data, cause of end-stage renal disease (ESRD), cause of readmission, ICU admission, time interval between transplantation and rehospitalization, costs, and in-patient mortality were compared between the two groups.

Mean (+/-SD) hospital stay was 10.6 +/- 9.8 days. Median hospital stay was 5 days for renal stones, 7 days for surgical complications, 8 days for malignancy, 9 days for infection, and 10 days for renal dysfunction. We found higher rates of ESRD due to diabetes in group I (28% vs. 15.4%; P=.006). Admissions due to infections (56.4% vs 42.4%; P=.003) or renal dysfunctions (55% vs 41.4%; P=.004) were the cause of higher proportions of total hospitalizations with prolonged stay. Prolonged stay also correlated with higher ICU admissions (8.8% vs 2.8%; P=.002) and mortality (6.7% vs 3.05%; P=.001). Mean total hospital cost for short versus prolonged hospitalizations were US$ 586 versus US$ 2750, respectively.

In this study, we found that prolonged hospital stays accounted for >62% of all hospital costs; however, they comprised only 26% of the patients. High-risk kidney transplant recipients for prolonged hospitalizations should be closely observed for infections and graft rejection.

This article summarizes the history of how renal stones have been treated over the centuries and reviews current treatments and outcomes for renal stones. The authors provide an algorithm based on available outcome data for shock wave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy.

During the preoperative evaluation of potential kidney donors, the increased sensitivity of spiral computed tomography (CT) could detect more asymptomatic small (less than 4 mm) renal calculi. However, whether these stones will be of consequence later has yet to be determined. We evaluated the rate of spontaneous passage, development of symptoms, and change in the size of asymptomatic renal calculi in donor kidneys transplanted without removal of the calculi.

Five donor kidneys from living donors were transplanted with small (less than 4 mm), asymptomatic renal calculi incidentally detected on CT (eight stones). No donors had any metabolic derangements or history of previous lithiasis. Each kidney was laparoscopically removed and transplanted with the calculi in situ. The recipients were followed up with serial creatinine measurements, history taking, and CT scans.

None of the recipients had had any symptoms consistent with the progression of disease, including hydronephrosis, renal failure, or the elevation of serum creatinine at a mean follow-up of 711 +/- 334 days. The follow-up CT scans showed spontaneous passage of the stones in 3 patients. In the remaining 2 patients, two of the stones remained stable, and one had increased in size from 1 to 2 mm. Those with the stones remaining had had a significantly shorter length of follow-up (204 +/- 72 versus 711 +/- 200 days, P <0.05).

In our series of 5 patients with small asymptomatic renal calculi, none of the patients have had complications, and only three of the eight stones were still in situ at the latest follow-up visit. Transplantation of small (less than 4 mm), asymptomatic stones in situ can be safely performed with adequate follow-up and monitoring for the development of obstructing transplant stones.

Although "in-hospital mortality" for several post-renal transplantation complications has been reported in various studies, there is no single published single-center study that compares their hospital mortality rates. We sought to rank the primary diagnoses post-renal transplantation by means of in-hospital mortality.

We selected 404 consecutive rehospitalizations following kidney transplantation from 2003 to 2005. The causes of rehospitalization were categorized into infection, allograft rejection, surgical complication, cerebrovascular accidents (CVA), malignancy, medication complications, and miscellaneous. Fatality was defined as the relative frequency of death due to the same cause among all admissions.

The mortality rate (MR) was 5.7%. From the 23 cases of death, 17 (74%) had a functioning kidney at the time of death. The MR was 40% for CVA, 14.3% for surgical complications, 11.1% for miscellaneous, 5.3% for drug complications, 7% for infections, and 4.8% for graft rejection (P=.002). No death was observed among cases with a diagnosis of malignancy or nephrolithiasis. Inpatient mortality was higher among those with more than one diagnosis at admission: 42.9% for more than two diagnosis, 7.1% for those with two diagnosis, and 4.2% for those with one diagnosis (P=.001).

The in-patient mortality ranking is totally different from the ranking of causes of death in renal recipients. In other words, infection is the leading cause of death due to high incidence, and not high fatality. More rare complications, including CVA and surgical complications, are more often fatal.

Despite a sizeable amount of research conducted hitherto into predictors of renal transplantation outcomes, there are scarce, data on predictors of in-hospital outcomes of post-kidney transplant rehospitalization. This study sought to provide a user-friendly prediction model for inpatient mortality and graft loss among rehospitalized kidney recipients.

This retrospective review of 424 consecutive kidney recipients rehospitalized after kidney transplantation between the years 2000 and 2005 used multiple logistic regression analysis to evaluate predictors of hospitalization outcomes.

Multivariate analysis showed that age at admission, diabetes mellitus as the cause of end-stage renal disease (ESRD), admission due to cerebrovascular accident (CVA), surgical complications were predictors of in-hospital death; age at transplantation, surgical complications, and rejection were predictors of graft loss. Equation for prediction of in-hospital death was Logit(death) -0.304 * age at transplantation (year) + 0.284 age at admission (year) + 1.621 admission for surgical complication + 4.001 admission for CVA-ischemic heart disease + 2.312 diabetes as cause of ESRD. Equation for prediction of in-hospital death was Logit(graft loss) = 0.041 age at transplantation (year) + 1.184 admission for graft rejection + 1.798 admission for surgical complication.

Our prediction equations, using simple demographic and clinical variables, estimated the probability of inpatient mortality and graft loss among re-hospitalized kidney recipients.

To report our experience with minimally invasive percutaneous nephrolithotomy (mPCNL) for upper urinary tract (UUT) calculi in transplanted kidneys.

Between August 2002 and June 2006, seven patients (mean age 40.7 years) with UUT stones in transplanted kidneys (including one staghorn, two pelvic and four ureteric stones) were treated by mPCNL. A 16 F peel-away sheath was placed as the percutaneous access port and a 8.5/11.5 F nephroscope or a 8/9.8 F ureteroscope was used for manipulation. Every 2-3 months during the follow-up, patients had their serum urea, creatinine and uric acid measured, with urine culture and ultrasonography.

All patients were rendered stone-free at one mPCNL procedure, with no complications during or after surgery. The mean (range) operative duration was 53 (20-100) min and the mean haemoglobin decrease was 0.55 (0.2-1.2) g/dL. At a mean (range) follow-up of 23 (3-48) months renal allograft function was stable in all patients and no recurrence of stone was detected.

mPCNL is safe and effective for managing calculi in transplanted kidneys, and it can be the initial therapy for most cases of UUT stones in transplanted kidneys, except for simple and small stones in the middle or lower calyx.

It has become increasingly important to refine therapeutic strategies according to individual patient characteristics. We evaluated the long-term impact of renal function at the time of withdrawing cyclosporine (CsA) in renal allograft recipients receiving sirolimus (SRL), CsA, and steroids (ST).

At 3 months+/-2 weeks, 430 of 525 patients were eligible to be randomized to remain on triple-therapy (SRL-CsA-ST, n=215) or to have CsA withdrawn (SRL-ST, n=215). Patients were divided into quartiles according to their baseline (last value before randomization) calculated GFR: <or=45 ml/min (quartile 1, n=104), >45 to 56 ml/min (quartile 2, n=105), >56 to 67 ml/min (quartile 3, n=112), and >67 ml/min (quartile 4, n=107). All data were included (ITT analysis).

At 4 years, calculated GFR for SRL-CsA-ST vs. SRL-ST was 22.1 vs. 37.7 ml/min (P=0.017), 38.6 vs. 56.6 ml/min (P<0.001), 50.7 vs. 66.8 ml/min (P=0.006), and 62.7 vs. 71.4 ml/min (P=0.436), for quartiles 1 to 4, respectively. Death-censored graft loss ranged from 21.2% vs. 7.7% (SRL-CsA-ST vs. SRL-ST, P=0.092) in quartile 1 to 5.5% vs. 1.9% (P=0.618) in quartile 4. The incidence of death and biopsy-confirmed acute rejection also decreased with increasing baseline GFR, but was not significantly different between treatments. Overall, more patients remained on therapy in the SRL-ST group (46.3% vs. 57.9%, P=0.020).

Early and complete withdrawal of CsA from a combination of SRL, CsA, and steroids was preferable to continuing on this regimen, regardless of baseline renal function. The benefit was most marked in patients with a baseline calculated GFR<or=45 ml/min.

To report the largest single series of renal transplant patients (adults and children) with urolithiasis, assess the risk factors associated with urolithiasis in renal transplant recipients, and report the outcome of the multimodal management by endourological and open procedures.

The records of all patients undergoing renal transplantation between 1977 and 2003 were reviewed. In all, 2085 patients had a renal transplant at our centre and 21 (17 adults and four children) developed urinary tract calculi. Their mode of presentation, investigations, treatments, complications and outcomes were recorded. Investigations included one or more of the following; ultrasonography (US), plain abdominal X-ray, intravenous urography, nephrostogram and computed tomography. Management of these calculi involved extracorporeal shock wave lithotripsy (ESWL), flexible ureteroscopy and in situ lithotripsy, percutaneous nephrolithotomy (PCNL), open pyelolithotomy and open cystolitholapaxy.

Thirteen patients had renal calculi, seven had ureteric calculi and one had bladder calculi. The incidence of urolithiasis was 21/2085 (1.01%) in the series. Urolithiasis was incidentally discovered on routine US in six patients, six presented with oliguria or anuria, including one with acute renal failure, four with a painful graft, three with haematuria, one with sepsis secondary to obstruction and infection and in one, urolithiasis was found after failure to remove a stent. Ten patients (63%) had an identifiable metabolic cause for urolithiasis, two by obstruction, two stent-related, one secondary to infection and in six no cause was identifiable. Thirteen required more than one treatment method; 13 (69%) were treated by ESWL, eight of whom required multiple sessions; eight required ureteric stent insertion before a second procedure and four required a nephrostomy tube to relieve obstruction. Two patients had flexible ureteroscopy and stone extraction, three had a PCNL and one had open cystolithotomy. PCNL failed in one patient who subsequently had successful open pyelolithotomy. All patients were rendered stone-free when different treatments were combined.

The incidence of urolithiasis in renal transplant patients is low. There is a high incidence of metabolic causes and therefore renal transplant patients with urolithiasis should undergo comprehensive metabolic screening. Management of these patients requires a multidisciplinary approach by renal physicians, transplant surgeons and urologists.