Acute Ureteral Obstruction Research Articles

3D dynamic diuretic renal scintigraphy using a hybrid whole body CZT SPECT/CT camera protocol in the evaluation of acute ureteric obstruction caused by ureteric stone

PurposeTo investigate the performance of dynamic 3D diuretic renal scintigraphy using a hybrid whole body CZT SPECT/CT for the evaluation of acute ureteric obstruction in patients with urinary stone disease.Methods20 patients who presented to the Emergency Department with acute renal colic due to urinary stone disease confirmed by means of CT were prospectively included. Three observers evaluated and graded hydronephrosis, hydroureter, perirenal stranding, and thickening of the renal fascia from the CT as well as the renal scintigraphy curves from the dynamic SPECT study. The normalized residual activity from dynamic SPECT was analysed at 16 min in all patients and at 20 min in suspected obstruction.ResultsRenal scintigraphy curves showed a sensitivity of 100%, specificity of 93%, PPV 83% and a NPV 100% for obstruction, while normalized residual activity showed a sensitivity of 100%, specificity of 73%, PPV 56% and a NPV 100%. All patients presented at least 2 secondary signs of obstruction on the CT, showing a PPV of only 25% for obstruction.ConclusionDynamic 3D diuretic renal scintigraphy CZT SPECT/CT provides valuable functional and anatomical information from one single examination. The combination of pathological renogram curves and high normalized residual activity values provide the most valuable imaging information to determine the presence of acute ureteric obstruction. The secondary signs of obstruction observed on CT are not specific and should not be used to confirm or discard obstruction in patients with urinary stone disease.Trial registration: ISRCTN15338358. Registration date 03/01/2024. Retrospectively registered. https://www.isrctn.com/ISRCTN15338358?q=miguel%20ochoa%20figueroa&filters=&sort=&offset=1&totalResults=2&page=1&pageSize=10

Safety and efficacy of ultrasound-assisted bedside ureteric stent placement A prospective, single-institution study.

Previous studies have demonstrated the feasibility of bedside placement of ureteric stents; however, they have traditionally required two skilled operators and were associated with some stent malposition especially for proximal ureteric obstruction. We sought to investigate the efficacy and safety of a modified technique for ultrasound-assisted bedside ureteric stent insertion without the presence of a skilled assist. A single institution prospective study was performed from April-August 2023. Indications for stenting included infection, renal insufficiency, or intractable colic. Exclusion criteria included age <18 years, hemodynamic instability, and patients with history of chronic pain. Point-of-care ultrasound (POCUS) was used to confirm wire placement in the kidney and presence of a hydronephrotic drip from a 5 French ureteric catheter was used to confirm placement beyond the level of obstruction. Of 28 patients, all patients underwent successful bedside ureteric stent placement. Mean age was 64.9 years and mean body mass index (BMI) was 33.2. Proximal ureter obstruction was present in 52% of patients and mid/distal obstruction in 48%. In cases with obstructing stones, the mean stone size was 8.1 mm with a range of 4-15 mm. Infection was the indication for stent placement in most patients (71%), followed by pain (4%) and acute kidney injury (AKI) (4%). All patients who underwent successful stent placement had presence of hydronephrotic drip from the ureteric catheter. Ultrasound-assisted bedside ureteric stent insertion without a skilled assist is a safe and feasible option for management of acute ureteral obstruction. Presence of hydronephrotic drip can indicate successful access beyond the level of obstruction as an alternative to POCUS.

Renal Fornix Rupture Due To Acute Ureteral Obstruction

Background: Renal fornix rupture with fluid extravasation is a rare complication in cases of ureteral obstruction, which is usually caused by obstructive ureterolithiasis. The symptoms of renal fornix rupture are not very specific and can easily go unnoticed due to their underlying cause. Case representation: The present article reports a case of a patient of a 70-year-old, male, who was diagnosed with a ruptured renal fornix due to acute ureteral obstruction, following clinical assessment and a non-contrast CT scan. The proposed course of action was the endoscopic placement of a double J ureteral catheter. Conclusion: In the case described, the conservative treatment that was chosen by passing a double J catheter through the left ureter, for the patient proved to be an alternative to surgical treatment in the acute event, reducing the risk of possible complications from the operation. It was possible to conclude that although renal fornix rupture is a rare emergency with multiple etiologies, conservative treatment with urinary diversion using a double J ureteral stent was effective in solving the patient's acute condition.

Cost-effectiveness of quality improvement intervention to reduce time between CT-detection and ureteroscopic laser fragmentation in acute symptomatic ureteric stones management

ObjectiveTo prospectively assess clinical and cost effectiveness of emergency ureteroscopic laser fragmentation of urinary stones causing symptoms or obstruction.Patients and methods100 consecutive patients with an average (median) age 55.6 (57.5) years and average (median) stone size of 8.2 mm (± 7 mm) between October 2018 and December 2021 who underwent emergency ureteroscopy and laser fragmentation formed the study cohort as part of a clinical service quality improvement. Primary outcome was single procedure stone-free rate and cost-effectiveness. The secondary outcomes were complications, re-admission and re-intervention. A decision analysis model was constructed to compare the cost-effectiveness of emergency ureteroscopy with laser fragmentation (EUL) and emergency temporary stenting followed by delayed ureteroscopy with laser fragmentation (DUL) using our results and success rates for modelling.ResultsSingle procedure stone-free rates (SFR) for EUL and DUL were 85%. The re-intervention rate, re-admission and complication rates of the study cohort (EUL) were 9%, 18%, and 4%, respectively, compared to 15%, 20%, and 5%, respectively for the control cohort (DUL). The decision analysis modelling demonstrated that the EUL treatment option was more cost-efficient, averting £2868 (€3260) per patient for the UK health sector. Total cost of delayed intervention was £7783 (€8847) for DUL in contrast to £4915 (€5580) for EUL.ConclusionsImplementation of quality improvement project based on a reduction in CT detection-to-laser fragmentation time interval in acute ureteric obstruction or symptoms caused by stones had similar clinical effectiveness compared to delayed ureteroscopic management, but more cost-effective.

Symptom of renal pelvic “pseudodissection” with computed tomography as a sign of pyelosinus reflux and urine extravasation

The purpose of the study . To find typical computed tomographic signs of pyelosinus reflux with a small amount of extravasation of urine. Material and methods . Eight observations were analyzed in which there was extravasation of urine into the renal sinus detected by CT. Results . In six cases, the changes were on the right, in two – on the left side. The cause of acute urinary tract obstruction in four cases were ureteral stones, in two cases there was compression of the ureter from the outside by a pelvic tumor. In two cases, a day after the relief of renal obstruction, the contrasted urine outside the pelvic was not determined. Additional findings were: flection of the ureter in two cases, renal sinus cysts – in four observations. In four observations an unusual “pseudodissection” of the renal pelvis in the excretory phase was revealed, which consisted in the presence of a thin non-contrasting layer "dividing" the contrasted contents of the pelvis into two parts. Conclusions . 1. Identification of the pattern of “pseudodissection” of the pelvis is practically a pathognomonic computed tomographic symptom of extravasation of urine as a result of pyelosinus reflux and rupture of renal calices. 2. Resolution of ureteral obstruction can lead to complete normalization of the computed tomographic picture during the day. 3. Inflection of the ureter, cysts of the sinus of the kidney, may be provoking factors of extravasation of urine in acute ureteral obstruction, but this requires further study.

Quantitative evaluation of upper urinary tract pump function in pigs with acute unilateral lower ureteral obstruction by 640-slice dynamic volume CT

BackgroundIt is a challenging problem to differentiate obstructive hydronephrosis from noninvasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in the quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs.MethodsIn this study, a perfusion pig model was constructed by constant pressure perfusion testing of the renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create a state of no obstruction and acute obstruction of the lower part of the left ureter. After successful modelling, continuous dynamic volume scanning of the bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analysed. No obstruction or acute obstruction of the lower part of the left ureter was observed. Pump functions of the renal pelvis and part of the upper ureter were determined.ResultsThe results showed that after LUUT fistulostomy, the time difference between the average UUT volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased with mild obstruction and decreased with severe obstruction, and there was a significant difference between the left and right sides.ConclusionThe continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function datasets of UUT in pigs with acute lower ureteral obstruction.

Suprapubic Catheter Migration: A Review of a Rare Complication

Background Suprapubic catheter migration to the vesicoureteral junction is an unusual complication, causing an obstruction that led to hydronephrosis and dilation of the pelvicalyceal system. Case presentation. A 30-year-old man with a suprapubic catheter (SPC) that was inserted one month before this current Emergency Department (ED) visit had severe left flank pain for 48 hours. The SPC was inserted in the context of urethral injury after falling astride. Point-of-Care Ultrasound (POCUS) showed a semifilled urinary bladder and moderate hydronephrosis on the left side. A computed tomography scan (CT scan) of the abdomen was performed and showed migration of the suprapubic catheter's tip into the left vesicoureteral junction, causing ureteral obstruction dilation of the ipsilateral pelvicalyceal system. The suprapubic catheter was changed in the ED, causing relief of symptoms, and the patient was referred to the urology department for follow-up. It was uneventful on the follow-up from the SPC clinic. Conclusions This case report describes a rare complication of migration of the suprapubic catheter to the vesicoureteral junction causing acute ureteral obstruction and hydronephrosis.

A Rare Case of Acute Postrenal Failure after Prostate Surgery

In patients with acute ureteral obstruction, rapid increase in ureteral pressure results in dilatation of the ureter and intrarenal collecting system that usually may cause renal colic. Computed tomography and ultrasound are the gold standard to evaluate uretero-hydronephrosis. We report a case of a patient who underwent a robot-assisted radical prostatectomy for cancer and developed anuria in the immediate postoperative course without pain or hydronephrosis. Clinical and conventional imaging can be normal in case of acute post-renal failure.

Live Renal Ultrasonography Facilitates Double-J Ureteral Stent Insertion at the Bedside: A Pilot Study for the COVID-19 Era.

Objectives: To investigate the feasibility and efficacy of live renal ultrasonography to guide Double-J ureteral stent placement at the bedside. Patients and Methods: Between April 12 and June 5, 2020, patients presenting with acute ureteral obstruction requiring decompression were prospectively selected for ultrasound-guided bedside ureteral stent placement. During stent placement, upper tract access confirmed using ultrasound with or without retrograde injection of ultrasound contrast before Double-J stent insertion. A postprocedural abdominal X-ray was obtained for stent position confirmation. Results: Eight patients (four men and four women) were offered bedside ultrasound-guided ureteral stent placement, and all eight consented to proceed. Stents were placed in seven of eight patients. One patient had an impacted ureterovesical junction stone and stricture requiring ureteroscopy and laser lithotripsy in the operating room. All patients tolerated procedures without immediate complications. Conclusion: Live renal ultrasonography can facilitate a high success rate for bedside ureteral stent placement outside the operating room. This approach is an attractive alternative to fluoroscopy-guided stent placement in the operating room and is of particular value in the COVID-19 era when judicious use of these resources is salient.

Doppler sonographic evaluation of resistive index of intra-renal arteries in acute ureteric obstruction.

Acute ureteric colic is one of the most commonly encountered acute abdominal conditions. Diagnosis of obstruction caused by ureteric calculus occasionally becomes challenging if there is inadequate dilation of the urinary tract proximal to obstruction. In such a situation, intra-renal artery Doppler parameters can be used as a diagnostic tool. Our study compared intra-renal arterial Doppler in patients with obstructed and non-obstructed kidneys presenting within 24h of onset of symptoms of unilateral acute renal colic. The resistivity index (RI) in the segmental arteries of all 54 patients with obstructed kidneys was significantly higher than in those with non-obstructed kidney: 0.75 vs. 0.56, with a p value less than 0.001, a sensitivity of 85% and a specificity of 93%. Doppler ultrasound is a useful diagnostic tool in the evaluation of acute renal obstruction, thus enabling practitioners to avoid ordering unnecessary CT and exposing patients to ionizing radiation. An RI value > 0.7 has good sensitivity and specificity in our study. The results obtained in the study were comparable to those of pioneer studies conducted worldwide.

Neutrophil gelatinase-associated lipocalin (NGAL) as a biomarker of renal injury in patients with ureteric stones: a pilot study

Objective: The role of neutrophil gelatinase-associated lipocalin in renal obstruction remains unclear. The aim of this study is to assess neutrophil gelatinase-associated lipocalin kinetics and its potential role as a biomarker of renal damage in acute ureteric colic. Methods: Thirty-six patients with acute ureteric colic were prospectively recruited and compared with two control groups. Blood and urine samples for plasma neutrophil gelatinase-associated lipocalin and urinary neutrophil gelatinase-associated lipocalin levels were obtained at various time points. Results: There were significantly higher levels of urinary neutrophil gelatinase-associated lipocalin and the urinary neutrophil gelatinase-associated lipocalin/creatinine ratio at presentation when comparing patients with acute ureteric colic to healthy controls ( P=0.002 and P=0.004, respectively). In patients with acute ureteric colic managed with surgical intervention ( n=27) there was a significant reduction in plasma neutrophil gelatinase-associated lipocalin ( P=0.001) and an increase in the urinary neutrophil gelatinase-associated lipocalin/creatinine ratio 6 hours postoperatively ( P=0.03). Eight of nine patients managed conservatively for acute ureteric obstruction had spontaneous stone passage at follow-up (median 26 days) with a significant reduction in the urinary neutrophil gelatinase-associated lipocalin/creatinine ratio ( P=0.03). Conclusion: The observation of a reduction in plasma neutrophil gelatinase-associated lipocalin and urinary neutrophil gelatinase-associated lipocalin levels following relief of renal obstruction due to ureteric stones suggests the potential role of neutrophil gelatinase-associated lipocalin as a biomarker in this scenario and in the follow-up setting as a potential marker of relief of obstruction. Level of evidence: 3b

Despite initial recovery of GFR, long-term renal functions deteriorate following short periods of unilateral ureteral obstruction.

Following the release of short periods of unilateral ureteral obstruction (UUO), glomerular filtration rate (GFR) recovers by time. However, research in experimental animal models has demonstrated the presence of an ongoing element of renal interstitial fibrosis a few weeks following UUO reversal. Interstitial fibrosis can cause deterioration in GFR, and it is not known whether it leads to an ongoing slow deterioration in other renal functions despite the apparent initial recovery postreversal. To investigate this, rats underwent a 72-h reversible UUO. Renal functions of nonobstructed and previously obstructed kidneys were measured 1, 4, and 18 mo postreversal. GFR in nonobstructed and previously obstructed kidneys was similar up to 18 mo postreversal. However, there was ongoing tubulointerstitial fibrosis, and the degree of tubular atrophy and dilatation deteriorated by time. This was associated with an increase in urinary albumin leakage and alterations in renal injury markers, proinflammatory and profibrotic cytokines, and p53 from 4 mo onward despite the recovery in GFR. In conclusion, several aspects of renal functions continue to deteriorate following reversal of relatively short periods of UUO despite the initial recovery in GFR. This might stimulate further research in this area and might have clinical implications in terms of determining the best time for intervention following acute ureteral obstruction and long-term monitoring of these individuals.

Thlaspi Bursa Pastoris in Treatment of Urinary Stones: A Case Series.

Urinary stones are the most common cause of acute ureteral obstruction. The homeopathic medicine Thlaspi bursa pastoris (TBP) has many symptoms similar to the typical symptoms of urolithiasis, yet its clinical usefulness has not been well documented. In this study, the clinical symptoms of each of five patients, along with ultrasonographic evidence, were taken for the assessment of the outcome. TBP was prescribed in potency 30c and/or 200c to each patient on the basis of the main symptoms, typically dysuria, retention of urine and haematuria. Each case was followed for up to 6 months. Assessment of causal attribution of treatment effect was performed using the Modified Naranjo Criteria. There was full recovery of all five patients and post-treatment ultrasonography showed no calculi remaining. The Modified Naranjo Criteria total score for each patient was either +8/13 or +9/13. TBP was observed to be effective in eliminating renal stones within a short span of time and without any complications.

Acute Ureteral Obstruction by Deeply Inserted Menstrual Cup

Mechanical complications from menstrual cups are rare, with only four reported cases of ureteral obstruction. Clinicians should be aware of gynecologic devices in patients with acute abdominopelvic pain because simple removal may obviate the need for further expensive work-up or exposure to ionizing radiation.

Minimally invasive management of acute ureteral obstruction and severe infection caused by upper urinary tract calculi.

PURPOSETo evaluate therapeutic efficacy of two minimally invasive surgical methods in managing acute ureteral obstruction and severe infection caused by upper urinary tract calculi (UUTC).PATIENTS AND METHODSData of 47 patients diagnosed with acute upper urinary tract obstruction and severe infection caused by ureteral calculus using X-ray CT between September 2014 and January 2019 were retrospectively analyzed. All patients were treated with immediate renal drainage and, after infection and ureteral obstruction were relieved, UUTC removal. Renal drainage was performed by ultrasound-guided percutaneous nephrostomy and retrograde ureteral catheterization was performed using cystoscopy. Kidney and ureteral stones were removed; renal function and the urinary tract were examined by X-ray during follow-up.RESULTSPercutaneous nephrostomy was performed in 29 patients in a critical condition including intolerance to surgery, high-grade hydronephrosis, or failure of retrograde ureteric stent placement. In other 18 patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis, indwelling double-J ureteral stents were temporally installed by a cystoscope. Acute infection and ureteral obstruction were relieved; white blood cell counts returned to normal values within 3 to 7 days after drainage in all patients. In the second-stage treatment, percutaneous nephrolithotomy (PCNL), ureteroscopic lithotripsy, extracorporeal shock wave lithotripsy and nephrectomy were performed in 24, 10, 8 and 5 patients, respectively. No patients developed severe complication after stone removal surgery. All patients were followed up for 3 months to 4.5 years. Renal function was significantly recovered; 17/29 (59%) patients with elevated serum creatinine returned to normal and serum creatinine in 12/29 (41%) patients improved significantly after drainage, with a pre-operation level of 285±169μM vs 203±91μM post-operation (P = 0.014). Five patients were lost during follow-up.CONCLUSIONThis study demonstrated an optimal approach for relieving upper urinary tract obstruction and acute infection in which percutaneous nephrostomy drainage is preferred for patients with severe pyonephrosis, large stones (>10 mm) with high-grade hydronephrosis, steinstrasse, or failure in retrograde ureteric stent placement, while retrograde ureteral catheterization using cystoscopy is suitable for patients diagnosed with small stones (≤10 mm) and low-grade hydronephrosis.

Intrarenal Arterial Doppler Evaluation in Acute Ureteric Obstruction

Intrarenal Arterial Doppler Evaluation in Acute Ureteric Obstruction

Ureteric stent versus percutaneous nephrostomy for acute ureteral obstruction - clinical outcome and quality of life: a bi-center prospective study

BackgroundTo compare quality of life (QoL) indices between ureteral stent (DJS) and nephrostomy tube (PCN) inserted in the setting of acute ureteral obstruction.MethodsProspective bi-centered study. Over the span of 2 years, 45 DJS and 30 PCN patients were recruited. Quality of life was assessed by 2 questionnaires, EuroQol EQ-5D and ‘Tube symptoms’ questionnaire, at 2 time points (at discharge after drainage and before definitive treatment).ResultsPatients’ demographics and pre-drainage data were similar. There were no clinically significant differences in patient’s recovery between the groups, including post procedural pain, defeverence, returning to baseline renal function, and septic shock complications.More DJS patients presented to the emergency room with complaints related to their procedure compared to PCN patients. At first, DJS patients complained more of urinary discomfort while PCN patients had worse symptoms relating to mobility and personal hygiene, with both groups achieving similar overall QoL score. At second time point, PCN patients’ symptoms ameliorated while symptoms in the DJS group remained similar, translating to higher overall QoL score in the PCN group.ConclusionsThe two techniques had a distinct and significantly different impact on quality of life. Over time, PCN patients’ symptoms relieve and their QoL improve, while DJS patients’ symptoms persist. Specific tube related symptoms, and their dynamics over time, should be a major determinant in choosing the appropriate drainage method, especially when definitive treatment is not imminent.

Perinephric Fat Stranding Is Associated with Elevated Creatinine Among Patients with Acutely Obstructing Ureterolithiasis.

Pyelovenous/pyelolymphatic backflow from acute ureteral obstruction, manifesting radiologically as perinephric fat stranding (PFS), may result in elevated serum creatinine. Among patients with acutely obstructing ureterolithiasis, we evaluated the relationship between degree of PFS and changes in serum creatinine from baseline. Our tertiary care center's radiology dictation system (Fluency Discovery, M Modal) was queried for noncontrast abdominopelvic CT studies obtained in the Emergency Department for patients with obstructing ureteral calculi from 7/2015 to 4/2016. A single radiologist blinded to clinical data reviewed all CT scans and coded stone size, location, severity of hydronephrosis, and degree of PFS (none, mild, moderate, severe). For patients who met imaging criteria, a retrospective chart review was performed. We evaluated 148 patients with mean age of 46 years (SD 14.6), 56.0% (n = 83) were male. On univariate analysis, moderate-severe perinephric stranding was associated with elevated creatinine from baseline (OR 2.93, p = 0.03). Mean creatinine increased as the severity of stranding increased (none Cr = 0.978 mg/dL, mild Cr = 0.983 mg/dL, moderate Cr = 1.165 mg/dL, severe Cr = 1.370 mg/dL; p < 0.01). An increase in creatinine from baseline was not associated with greater severity of hydronephrosis (OR 0.504, p = 0.189). There was no association between degree of PFS and severity of hydronephrosis, positive urine culture, stone location, or symptom duration (p > 0.05). On regression analysis controlling for positive urine culture and degree of hydronephrosis, there remained an association between elevated serum creatinine from baseline and moderate-severe PFS (OR 9.0, p = 0.01). Among patients with acute obstructive ureterolithiasis, moderate-severe PFS was associated with elevated serum creatinine from baseline. This elevated creatinine was not explained by the obstructed kidney alone, as there was no association between the severity of hydronephrosis and increased creatinine. Pyelovenous/pyelolymphatic backflow resulting in PFS may be a contributing factor to elevated serum creatinine in this setting.

Salivary Neutrophil Gelatinase-Associated Lipocalin Sampling Feasibility in Acute Renal Colic.

Neutrophil gelatinase-associated lipocalin (NGAL) levels in the serum and urine are predictive biomarkers of acute kidney injury with correlation to complication and survival in major surgery. Salivary levels of NGAL during acute renal colic may reflect the degree of renal injury as it appears in different compartments encompassing body response in time perspective. Our aim is to evaluate and examine the feasibility and correlation of salivary NGAL with serum and urine levels in acute renal colic event. A prospective controlled study of all patients presenting to the emergency room with acute renal colic event diagnosed with single ureteral stone obstruction by noncontrast CT. Saliva, urine, and blood samples were collected in patients and a control group during the first morning of admission. The study groups consisted of 44 patients and 13 controls, mean age 47 ± 15 years, body mass index 29 ± 6, mean stone size 6 ± 4 mm, mean creatinine levels 1.3 ± 0.7 mg/dL, mean white blood count 10,900 ± 3100 counts per field, and C-reactive protein 29 ± 55. Serum (190 ± 120 ng/mL vs 81 ± 24; p < 0.001) and predominantly salivary (474 ± 185 vs 328 ± 134 ng/mL; p < 0.05) NGAL levels were significantly elevated in patients compared with controls. Salivary NGAL sampling is feasible during the acute phase of renal colic. High levels of salivary NGAL are observed in a single sampling during acute ureteral stone obstruction and may advance clinical decision-making.

Unexpected presentation of allograft dysfunction triggered by page kidney phenomenon immediately after kidney transplantation: a case report

BackgroundPage kidney phenomenon is caused by strong renal parenchymal compression and leads to renal hypoperfusion and microvascular ischemia, resulting in renal dysfunction and hypertension. Although the development of Page kidney phenomenon in allograft is rare, most of its cases are induced by allograft biopsy or trauma. We observed a case of Page kidney phenomenon that was induced by unusual causes immediately after kidney transplantation.Case presentationA 66-year-old man, whose wife donated a kidney, underwent ABO-compatible living kidney transplantation. The allograft had three renal arteries that were trimmed and formed into one piece on the back table, and subsequently, it was anastomosed to the internal iliac artery. Intraoperative Doppler ultrasonography (US) revealed adequate blood flow of each renal artery. Urine output was also observed as soon as allograft blood flow was reperfused. After the surgery, the urine output decreased, and serum creatinine level increased to 6.0 mg/dL. Doppler US did not show evidence of acute rejection, ureteral obstruction, or anastomotic stenosis of the renal arteries. On postoperative day 7, surgical exploration was performed and revealed that the blood flow of each renal artery was adequate but subcapsular hematoma was detected at the upper pole of the allograft. Capsulotomy and hematoma evacuation were performed. Subsequently, urine output increased and serum creatinine level decreased up to 1.7 mg/dL. Allograft sample was obtained 1 h after the transplantation from the lower pole of the allograft. Although the cause of subcapsular bleeding was unclear in this case, a small cyst of the allograft, which might have ruptured during donor nephrectomy, was located in the middle of the hematoma, and oozing around the cyst was observed.ConclusionsOur case indicated that the small ruptured cyst of the allograft could be the cause of subcapsular hematoma and Page kidney phenomenon. Subcapsular hematoma caused by oozing over time could be difficult to diagnose using Doppler US, and thus, other imaging modalities, such as computed tomography, should be considered. Knowledge of the Page kidney phenomenon in the allograft can lead to early diagnosis and intervention, resulting in better outcomes for recipients with allograft dysfunction.