Kidney fusion anomalies revisited: clinical and radiological analysis of 209 cases of crossed fused ectopia and horseshoe kidney

Combined therapy for managing a clear cell renal cell carcinoma in a horseshoe kidney: A case report

The upper urinary tract is the most common human organ system affected by congenital anomalies. A Horseshoe kidney is a fusion anomaly, it can be described as a fusion across the midline of 2 distinct functioning kidneys. The incidence of renal tumors in a Horseshoe kidney is higher than in the normal population. We present a 60-year-old male patient with a history of Horseshoe kidney and a diagnosis of clear cell renal cell carcinoma who underwent a combined therapeutic approach, guided by interventional radiology. This approach involved selective transarterial embolization and microwave ablation. Three months after surgery and with abdominal MRI follow-up, there is evidence of a non-viable tumor, indicating a favorable response to the intervention.

Lower and upper urinary tract urothelial carcinoma in crossed fused ectopic kidney

Urothelial tumors in patients with anatomical abnormalities may pose significant challenges. Management follows the same principles which are employed in normal anatomy, however, thorough diagnostic investigation is warranted in order to delineate key anatomical landmarks. Meticulous pre-operative investigation should utilize every imaging modality which can assist the surgeons. We present a case of transitional cell carcinoma (TCC) in a crossed-fused kidney treated with nephro-ureterectomy. Only a handful of cases of TCC in CFRE have been reported. The case demonstrates the critical role of pre-operative anatomical studies and intra-operative identification of unique anatomy, which facilitate treatment and avoid complications.

Single Branch Endovascular Aortic Repair Procedure for an Abdominal Aortic Aneurysm in a Patient With Horseshoe Kidney: A Case Report

Introduction

Horseshoe kidney (HK) is an anatomical variant characterised by abnormalities in the position, rotation, and vascular supply of the kidney, with functioning renal masses on both sides of the vertebral column fused together at the isthmus. Due to the altered pattern of kidney vasculature, endovascular aortic repair for aortic abdominal aneurysm (AAA) in the presence of HK requires vascular anatomy specific planning.

Report

A 68 year old male, with multiple comorbidities, presented with an asymptomatic AAA and HK. The kidney vasculature was characterised by the presence of three arteries: two arising laterally at the same level and a third polar artery arising from below. The polar artery was 6 mm in diameter and larger than the other two; therefore, in order to preserve this artery, a custom-made device with a single side branch was implanted below the main renal arteries. A balloon expandable covered stent was used to complete the side branch into the polar renal artery. The follow-up computed tomography angiography revealed a successful outcome, with total aneurysm exclusion, branched graft patency, no endoleak, and unchanged renal function.

Discussion

This case report shows a possible surgical solution for a case of HK with AAA and the importance of accurate endovascular planning. Large polar arteries, if present, need to be preserved, and custom-made devices in the modern endovascular era permit that. This approach could represent the best option for complicated patients.

Crossed fused renal ectopia diagnosed in an adult: Case report

INTRODUCTION AND IMPORTANCE

Crossed fused renal ectopia is one of the rare congenital anomalies in which a kidney is found on the side opposite to its normal anatomical location and is fused with the contralateral kidney. Most patients are asymptomatic and diagnosed incidentally.

CASE PRESENTATION

In this case report we present a 60 year old woman diagnosed with a left to right crossed fused renal ectopia with fusion of the left kidney to the inferior pole of the right kidney. The patient presented with vague abdominal pain and diagnosis was made with abdominal ultrasound and CT urography.

CLINICAL DISCUSSION

Though usually asymptomatic, a number of anomalies and complications can be associated with crossed fused renal ectopia including obstruction, stone disease, and tumors. Evaluation and diagnosis usually requires cross sectional imaging. Patients who are asymptomatic and without complications can be managed conservatively.

CONCLUSION

Crossed fused renal ectopia is one of the rare congenital anomalies which can be associated which needs cross-sectional imaging for adequate evaluation. Associated anomalies and complications should be carefully looked for since management depends on it.

The Discovery of an S-shaped Kidney in a Patient With Prostate Cancer: A Rare Finding

Crossed fused renal ectopia (CFRE) constitutes a rare congenital anomaly of the urinary tract, typically characterized by its predominantly asymptomatic nature and frequent incidental discovery. This case report delineates the clinical profile of a 56-year-old male admitted to our Prostate Cancer Outpatient Clinic due to elevated prostate-specific antigen (PSA) levels, ultimately leading to the diagnosis of prostate cancer. The patient was asymptomatic, with no family or surgical background. Notably, a fused ectopic kidney was incidentally identified during the staging process involving abdominal computed tomography (ACT) scanning. Remarkably, no additional abnormalities of the urinary tract or renal dysfunction manifested in this specific case. The significance of this report lies in the underscored emphasis on the importance of employing precise imaging techniques and tailored management strategies for patients harboring such anatomical variations.

Supine mini percutaneous nephrolithotomy in horseshoe kidney

OBJECTIVE

The percutaneous nephrolithotomy (PCNL) in Horseshoe kidneys (HSK) is usually performed in the prone position, allowing entry through the upper pole and providing good access to the collecting system. However, in patients with normal kidney anatomy, the supine position is reliable and safe in most cases, but it is unknown whether the supine position is adequate in patients with HSK. The purpose of this study was to describe the results of PCNL in HSK in three different surgical institutions and to evaluate the impact of supine position during surgery, comparing pre-operative and post-operative data, complications, and stone status after surgery.

MATERIAL AND METHODS

Between 2017 and 2022, a total of 10 patients underwent percutaneous renal surgery for stone disease in HSK. All patients were evaluated pre- and post- operatively with non-contrast CT. we evaluated patients (age and gender), stones characteristics (size, number, side, site and density ), and outcomes. The change in haemoglobin, hematocrit, creatinine and eGFr were assessed between the most recent preoperative period and the first postoperative day. Procedure success was defined as stone-free or presence of ≤4 mm fragments (Clinically Insignificant residual Fragments - CIrF). Complications were registered and classified according to Clavien-dindo Grading System, during the 30 - day postoperative period and Clavien scores ≥ 3 were considered as major complications. Statistical analysis was performed using "r 4.2.1" software, with a 5% significance level. we also compared pre-operative and post-operative data using "wilcoxon signedrank test".

RESULTS

No statistical difference was observed between preoperative and post-operative renal function data. At one post operative day CT scan, an overall success rate of 100% was registered. 9/10 patients were completely free from urolithiasis (stone-free rate: 90%), while 1/10 patients had ≤4 mm residual stone fragments (CIrF rate: 10%). No cases of intraoperative complications were registered. Post-operative complications were reported in 1/10 patients. A patient developed urosepsis (defined as SIrS with clinical signs of bacterial infections involving urogenital organs - Clavien-dindo Grade II) after procedure, and was treated with intravenous antibiotic therapy successfully.  Conclusions: This study shows that in patients with HSK mini- PCNL in supine position allows to achieve good stone free rate with a very low morbidity. According to our series, the described technique for PCNL in HSK should be an option. Nevertheless these results must be confirmed by further studies.

Implications of Tumor Surgery in Horseshoe Kidneys: A Comparative Study of Outcomes and Surgical Practices

OBJECTIVE

To contrast surgical outcomes of Horseshoe Kidney (HSK) patients with localized renal masses suspected of cancer with nonfused nonectopic kidney patients, emphasizing safe surgical practices for HSKs.

METHODS

The study examined solid tumors from the Mayo Clinic Nephrectomy registry between 1971 and 2021. Each HSK case was matched to three non-HSK patients based on various factors. The outcomes measured included complications within 30days of surgery, change in estimated glomerular filtration rate, and overall, cancer-specific, and metastasis-free survival rates.

RESULTS

Thirty of the 34 HSKs had malignant tumors compared with 90 of the 102 patients in the nonfused nonectopic referent cohort. Accessory isthmus arteries were present in 93% of HSK cases, with 43% exhibiting multiple arteries and 7% with 6 or more arteries. Estimated blood loss and surgery duration were significantly higher in HSKs (900 vs 300 mL, P = .004; 246 vs 163 minutes, P < .001, respectively). The HSK group demonstrated an overall complication rate of 26% (vs 17% in referents, P = .2) and a median change in estimated glomerular filtration rate at 3months of - 8.5 (vs -8.1 in referents, P = .8). At 5-year follow-up, survival rates for HSK patients were 72%, 91%, and 69% for overall, cancer-specific, and metastasis-free survival, respectively. The corresponding rates were 79%, 86%, and 77%, respectively, for matched referent patients (P > .05).

CONCLUSION

HSK tumor management is technically challenging with higher blood loss; however, the data demonstrate comparable outcomes for patients with HSK tumors, including complications and survival, to those without HSKs in experienced centers.

Horseshoe Kidney: 500 Years From the First Report in the Literature

Horseshoe kidney or ren arcuatus is the most common renal fusion anomaly, with an incidence of 1:500 in the normal population and a male predominance of 2:1. In >90% of cases, the fusion occurs along the inferior pole. It may vary in location, orientation, and arterial and venous anatomy. In 1522, Berengario da Carpi described this renal malformation for the first time in his masterpiece "Isagogae breves" (Introduction to Anatomy). He reported the results of a postmortem examination in the public autopsy room of the University of Bologna, describing "kidneys that are continuous as if they were a kidney, with two emulsifying veins, two emulsifying arteries, two ureteral outlets." In 1564, Leonardo Botallo described and illustrated the features of this atypical anatomical representation, and later, in 1602, Leonard Doldius added further details by examining this anatomical feature during an autopsy. In 1761, Giovanni Battista Morgagni discussed this condition not only as a rare anatomical curiosity found only in necroscopy but also discussed its physiological aspect. In the nineteenth century, with the advent of renal surgery, the horseshoe kidney played a more important role in urological diagnosis and treatment, and its identification became more frequent. With the advent of pyelography, imaging reports of the horseshoe kidney allowed a more accurate representation of the anatomical variants, which was particularly useful in preoperative assessment and outcomes. Berengario da Carpi laid the foundation for a better knowledge of this anatomical anomaly. Five hundred years after the first report in the literature, relevant advances have been made in the management of complications associated with horseshoe kidney and in diagnosis, confirming the need to monitor individuals with this condition who are at higher risk of developing chronic kidney disease.

Antenatally Diagnosed Kidney Anomalies

Congenital anomalies of the kidney and urinary tract encompass a broad spectrum of developmental conditions that together account for the majority of childhood chronic kidney diseases. Kidney abnormalities are the most commonly diagnosed congenital anomaly in children, and detection of this anomaly is increasing as a result of improved antenatal care and widespread access to more sensitive screening ultrasonography. Most paediatricians will encounter children with congenital kidney anomalies across a wide spectrum of disorders, and a broad understanding of the classification, investigation, and basis of management is important to appropriately direct their care.

Anatomy and embryology of congenital surgical anomalies: Congenital Anomalies of the Kidney and Urinary Tract

Congenital anomalies of the kidney and urinary tract or "CAKUT" describes a spectrum of developmental disorders with a range of associated clinical presentations and functional consequences. CAKUT underlies the majority of chronic kidney disease and kidney replacement therapy requirement in children, but functional deterioration can also emerge in adulthood. Understanding the normal embryological processes involved in kidney development allows us to appreciate the timing and sequence of critical events implicated when things go wrong. In this review, we will describe the normal developmental mechanisms and relate this to what we currently know about the pathological processes involved in various forms of CAKUT. We will also review the proposed etiological factors, in particular genetics, involved in CAKUT.

Quantitative assessment of renal obstruction in multi-phase CTU using automatic 3D segmentation of the renal parenchyma and renal pelvis: A proof of concept

Purpose

Quantitative evaluation of renal obstruction is crucial for preventing renal atrophy. This study presents a novel method for diagnosing renal obstruction by automatically extracting objective indicators from routine multi-phase CT Urography (CTU).

Material and methods

The study included multi-phase CTU examinations of 6 hydronephrotic kidneys and 24 non-hydronephrotic kidneys (23,164 slices). The developed algorithm segmented the renal parenchyma and the renal pelvis of each kidney in each CTU slice. Following a 3D reconstruction of the parenchyma and renal pelvis, the algorithm evaluated the amount of the contrast media in both components in each phase. Finally, the algorithm evaluated two indicators for assessing renal obstruction: the change in the total amount of contrast media in both components during the CTU phases, and the drainage time, "T1/2", from the renal parenchyma.

Results

The algorithm segmented the parenchyma and renal pelvis with an average dice coefficient of 0.97 and 0.92 respectively. In all the hydronephrotic kidneys the total amount of contrast media did not decrease during the CTU examination and the T1/2 value was longer than 20 min. Both indicators yielded a statistically significant difference (p < 0.001) between hydronephrotic and normal kidneys, and combining both indicators yielded 100% accuracy.

Conclusions

The novel algorithm enables accurate 3D segmentation of the renal parenchyma and pelvis and estimates the amount of contrast media in multi-phase CTU examinations. This serves as a proof-of-concept for the ability to extract from routine CTU indicators that alert to the presence of renal obstruction and estimate its severity.

Optimal patient position for percutaneous nephrolithotomy in horseshoe kidneys: Traditional prone or supine?

OBJECTIVE

Although it was stated that supine percutaneous nephrolithotomy (PCNL) was associated with relatively shorter surgical times and comparable success and complication rates, there is no consensus in the current literature concerning the safety and efficacy of supine PCNL in patients with horseshoe kidneys. We aimed to compare supine and prone PCNL regarding safety and efficacy in patients with horseshoe kidneys.

METHODS

Data of the patients with horseshoe kidneys who underwent PCNL for renal stones larger than 2 cm between January 2010 and May 2021 were retrospectively reviewed. The study patients were categorized as Group 1 (i.e., supine PCNL-SPCNL) and Group 2 (i.e., prone PCNL-PPCNL). Both groups were compared regarding demographic, clinical, and surgical data.

RESULTS

Sixty-five patients were included. Among these patients, 31 (47.7%) were in Group 1, while 34 (52.3%) were in Group 2. Both groups were statistically similar in terms of demographic data, stone characteristics, perioperative parameters, and complication rates (p > 0.05). There was no statistical difference in terms of additional treatment rates, stone-free rates in the postoperative second-day and third-month evaluations (p > 0.05). Mean surgical time was significantly longer in Group 2 (113 ± 17.1 min) than in Group 1 (90.6 ± 11.3 min) (p = 0.000).

CONCLUSION

Although it is traditionally performed in the prone position, the supine approach is as safe and effective as the prone approach. In addition, the supine approach is associated with significantly shorter surgical times.

Polycystic Horseshoe Kidney: A Rare Coexistence as a Challenge for the Surgeons. Case Report

Autosomal dominant polycystic kidney disease (ADPKD) with concomitant horseshoe kidney is an extremely rare entity. In this case, we report a 45-year-old male patient with ADPKD and a horseshoe kidney who demonstrated hypertension, urological complications, and discomfort symptoms such as pain, breathing difficulties, and abdominal meteorism. After preoperative assessment and planning, the patient underwent nephrectomy. Bilateral nephrectomy without dividing the isthmus was performed successfully. The isthmus, which had complicated vasculature and was full of cysts, remained intact, avoiding severe bleeding and infection. The postoperative course was uneventful. Keeping the isthmus intact in such cases is a challenge for the surgeon. The rarity of polycystic horseshoe kidney in combination with the altered abdominal anatomy requires the proper preoperative strategy in order to avoid intraoperative complications.

Laparoscopic Heminephrectomy in Horseshoe kidney: single-center experience of four cases

Background

Horseshoe kidney (HSK) is the most common congenital fusion anomaly and found in 1 in 400 of the general population (Grainger et al. in Ir Med J 76:315–317, 1983 Jul). Impaired drainage due to anomalous anatomy leads to ureteric obstruction resulting in hydronephrosis and nonfunctioning kidney.

Conventionally heminephrectomy is done by open technique; however, in the era of minimally invasive surgery, laparoscopic heminephrectomy in HSK has been described. Kidney location, aberrant vasculature and isthmus division are the most common obstacle encountered by the operating surgeon. Here we report our single-center experience in laparoscopic heminephrectomy in four patients with HSK.

Methods

Retrospective data were analyzed for four cases of laparoscopic heminephrectomy for nonfunctioning moiety in HSK operated between 2012 and 2020. Of these four patients, one case was converted to open approach in view of intra-operative bleeding. Computed tomography urogram (CTU) was done pre-operatively in all patients. Laparoscopic surgery was performed via transperitoneal approach.

Results

The mean age of the patients was 37 ± 5.38 years. Flank pain was noted in all cases while dysuria seen in two patients and one patient had fever. Mean operative time was 145 ± 26.92 min and estimated blood loss was 85 ± 55 ml. Various techniques for isthmectomy and lower pole resection were used including use of monopolar hook in laparoscopic suite, Ligasure and bipolar scissor in minimal invasive milieu and monopolar cautery in laparoscopic conversion to open procedure. Histopathological examination revealed chronic pyelonephritis in three cases and squamous cell carcinoma of renal pelvis in one case which was converted to open.

Conclusions

Laparoscopic heminephrectomy in HSK is doable. Preoperative CT urography along with CT angiography may provide important anatomical and vascular information which reduces intra-operative risks of vascular injury or calyceal entry. Vascular control of isthmus and transection of dilated and thinned out lower pole with cauterization of pelvicalyceal mucosa will provide uneventful surgical course.

Unveiling the confusion in renal fusion anomalies: role of imaging

Renal fusion anomalies are common congenital anomalies of the urogenital tract and have their genesis in the early embryonic period. They are classified into partial fusion anomalies (e.g., crossed fused ectopia, and horseshoe kidney) and complete fusion anomalies (e.g., fused pelvic kidney). Horseshoe kidney is the most common renal fusion anomaly and is characterized by the presence of two distinct functioning kidneys on either side of the vertebral column, with fusion occurring at the inferior poles in majority of the cases. Crossed fused ectopia is characterized by the presence of an ectopic kidney that crosses the midline and fuses with the orthotopic contralateral kidney, whereas fused pelvic (pancake) kidney is a complete fusion anomaly characterized by extensive medial fusion of both kidneys in the pelvis. Fusion anomalies are often associated with abnormalities of renal rotation, migration, and vascular supply, which predispose the kidneys to a number of complications and create difficulty during retroperitoneal surgeries and interventions. They are also associated with other congenital abnormalities of the urogenital tract, gastrointestinal tract, cardiovascular system, and skeletal system. Hence, a thorough understanding of the etiopathogenesis and radiological features of fusion anomalies is important for directing patient management. This review summarizes the embryological basis, clinical presentation and imaging approach to renal fusion anomalies, followed by detailed anatomical and radiological description of the morphological types, and the complications associated with these anomalies.

Crossed fused renal ectopia: Diagnosis and prognosis as a single-center experience

BACKGROUND

Crossed fused renal ectopia (CFRE) is a rare congenital malformation. Renal bladder ultrasound (RBUS) is a good tool for establishing the diagnosis, however, additional imaging with a voiding cystourethrogram (VCUG) and dimercaptosuccinic acid scan (DMSA) might be required. We assessed the need for postnatal evaluation and the long-term consequences in patients with this diagnosis.

METHODS

A retrospective review of the records of all patients diagnosed with CFRE between 2004 and 2014 was done. We included all patients who underwent postnatal evaluation with RBUS, DMSA and VCUG. Long-term radiological and functional outcomes were assessed.

RESULTS

A total of 29 patients with CFRE were identified. Majority of cases were detected antenatally (79%) and left to right crossed ectopia constituted the majority of cases (65%). RBUS revealed associated hydronephrosis (HN) in 11 patients (38%). DMSA scans confirmed the diagnosis in all patients and showed impaired renal function in 10 ectopic kidneys (34%). Vesicoureteral reflux was detected in 12 patients (41%); one third of them needed surgical intervention. Extra-urinary anomalies were present in 14 patients (48%) mainly of cardiac origin. After a mean follow-up of 4.5 years, 4 patients (14%) with extra-urinary anomalies developed chronic kidney disease and two of them died.

CONCLUSIONS

Crossed fused renal ectopia is commonly associated with both urinary and extraurinary malformations. Postnatal RBUS is usually sufficient for diagnosis, however, additional imaging may aid for confirming the diagnosis and detection of associated urinary anomalies. Presence of extra-urinary malformations with crossed fused ectopia carries a higher risk of morbidity.

TYPE OF THE STUDY

Retrospective study [diagnostic/prognostic study].

LEVEL OF EVIDENCE

Level IV.

Horseshoe kidney with PLA2R-positive membranous nephropathy

Background

Horseshoe kidney (HSK) is a common congenital defect of the urinary system. The most common complications are urinary tract infection, urinary stones, and hydronephrosis. HSK can be combined with glomerular diseases, but the diagnosis rate of renal biopsy is low due to structural abnormalities. There are only a few reports on HSK with glomerular disease. Here, we have reported a case of PLA2R-positive membranous nephropathy occurring in a patient with HSK.

Case presentation

After admission to the hospital due to oedema of both the lower extremities, the patient was diagnosed with nephrotic syndrome due to abnormal 24-h urine protein (7540 mg) and blood albumin (25 g/L) levels. Abdominal ultrasonography revealed HSK. The patient’s brother had a history of end-stage renal disease due to nephrotic syndrome. Therefore, the patient was diagnosed with PLA2R-positive stage II membranous nephropathy through renal biopsy under abdominal ultrasonography guidance. He was administered adequate prednisone and cyclophosphamide, and after 6 months of treatment, urinary protein excretion levels significantly decreased.

Conclusion

The risk and difficulty of renal biopsy in patients with HSK are increased due to structural abnormalities; however, renal biopsy can be accomplished through precise positioning with abdominal ultrasonography. In the literature, 20 cases of HSK with glomerular disease have been reported thus far. Because of the small number of cases, estimating the incidence rate of glomerular diseases in HSK is impossible, and the correlation between HSK and renal pathology cannot be stated. Further studies should be conducted and cases should be accumulated to elucidate this phenomenon.

Wilms' Tumor in Horseshoe Kidney

Wilms' tumor is the most common malignant kidney tumor found in children. The Horseshoe kidney is the most common renal fusion malformation. However, Wilms' tumor is rarely identified in horseshoe kidney patients. Multimodal treatments in Wilms' tumor can play important roles in increasing the survival rate. In this study, we report the case of a 6-year-old boy in whom a Wilms' tumor was identified in a horseshoe kidney. The tumor was successfully treated with preoperative chemotherapy, followed by surgical resection.

Renal Arteries Revisited: Anatomy, Pathologic Entities, and Implications for Endovascular Management

The renal arteries (RAs) are important vessels that usually arise from the abdominal aorta and supply the kidneys; thus, these arteries play a vital role in physiologic functions such as hemofiltration and blood pressure regulation. An understanding of the basis for embryologic development and the frequently variable anatomy of the RAs is necessary to fully appreciate the range of diseases and the implications for procedural planning. Hemorrhage from an RA is relatively common and is typically traumatic or spontaneous, with the latter form often seen in association with underlying tumors or arteriopathy. Accurate diagnostic evaluation of RA disease due to conditions such as atherosclerosis, fibromuscular dysplasia, vasculitis, aneurysm, arteriovenous shunt, embolic disease, and dissection is dependent on the use of multimodality imaging and is essential for selecting appropriate clinical management, with endovascular therapy having a key role in treatment. Surgical considerations include extra-anatomic renal bypass, which remains an important treatment option even in this era of endovascular therapy, and RA embolization as an adjunct to tumor surgery. A novel area of research interest is the potential role of RA denervation in the management of refractory hypertension. ^©RSNA, 2021.

Horseshoe kidney leading to ERCP failure; innovative use of guide wire during laparoscopic CBD exploration: A case report

INTRODUCTION

Horseshoe kidneys are the most common fusion defect of the kidneys, which amounts to about 0.25% of the population. They are usually asymptomatic and are often identified incidentally. The horseshoe kidney can push the second and third part of the duodenum anteriorly, leading to an altered CBD course. Choledocholithiasis is seen in approximately 10-15% of patients with cholelithiasis. Presently, the most preferred approach for managing CBD stones is ERCP. However, in ERCP failure cases, Laparoscopic CBD exploration is the primary treatment modality, with or without T-tube use, with all the advantages of minimally invasive surgery.

CASE PRESENTATION AND DISCUSSION

A 65-year-old female presented with complaints of pain in the right hypochondriac region for three months associated with nausea, jaundice, and loss of appetite and weight. Her USG abdomen showed cholelithiasis with dilated CBD with horseshoe kidney with severe hydronephrosis of the left kidney. They are usually asymptomatic and are often identified incidentally. In this patient, it was believed that the horseshoe kidney had pushed the second and third part of the duodenum anteriorly, leading to an altered CBD course leading to ERCP failure. MRCP confirmed cholelithiasis with choledocholithiasis with dilated CBD of 11.3 mm with horseshoe kidney. ERCP was attempted but was unsuccessful due to non-visualization of the papilla due to overcrowding of duodenal folds. For patients with ERCP failure, laparoscopic CBD exploration is mandatory. For this patient, the CBD was cannulated with a guidewire, if needed, for repeat ERCP and was closed with T-tube in situ.

CONCLUSION

There are no particular preoperative indicators that can predict the failure of ERCP. However, in ERCP failure cases, laparoscopic CBD exploration (with or without T-tube use) is the primary treatment modality.

Malformative Reno-Urinary Pathology in Patients with HIV Infection-Clinical and Therapeutic Implications

Chronic kidney disease is an important comorbidity of HIV infection causing real problems in the evolution and medical healthcare of HIV-positive patients. In recent years, a significant number of HIV-positive patients develop renal dysfunction, several mechanisms being incriminated: direct effect of the virus, toxic effect secondary to of antiretroviral medication, secondary to associated comorbidities, given that life expectancy has increased significantly in the last decade, thanks to the use of antiretroviral therapies. There are few studies in the literature to evaluate malformative renourinary pathology in patients with HIV infection. We present the case of a patient with HIV infection, horseshoe kidney, chronic kidney disease and incomplete Fanconi syndrome, secondary to the administration of tenofovir fumarate, a nucleoside reverse transcriptase inhibitor. Malformations, abnormalities or dysmorphysms of the renal tract should be considered in the HIV-positive patient with secondary renal dysfunction because they take a wide range of forms, are underdiagnosed and predispose to multiple complications, with varying degrees of severity, such as urinary tract infections, renal stones or progression of chronic kidney disease. Tenofovir fumarate and atazanavir must be avoided in patients with HIV infection and chronic renal dysfunction.

Bilateral pelvic kidneys with upper pole fusion and malrotation: a case report and review of the literature

BACKGROUND

The incidence of ectopic kidneys is 1:12,000 clinically and 1:900 postmortem. Patients with pelvic mal-rotated kidneys are more susceptible to recurrent urinary tract infections, recurrent renal stones, and renal injury. Fusion of the kidney lower poles is relatively common compared to other types of renal anomalies.

CASE PRESENTATION

We present the case of a 36-year-old Sudanese female patient who presented with a long history of recurrent urinary tract infections unresponsive to antibiotics. Ultrasound scan revealed bilateral pelvic kidneys. Computed tomography (CT) urography confirmed bilateral ectopic fused kidneys, with the left kidney mal-rotated (renal pelvis facing upwards and laterally). Kidney infection secondary to vesicoureteral reflux was diagnosed. Antibiotics were prescribed according to culture and sensitivity. The patient responded well to ciprofloxacin.

CONCLUSION

A history of recurrent urinary tract infections without an apparent cause is highly suggestive of renal anomaly and should be investigated expediently. Ultrasonography or CT imaging may be utilized to aid in diagnosis. Early recognition may help prevent the high risk of end-stage renal failure associated with anomalies.

Renal outcomes in adult patients with horseshoe kidney

BACKGROUND

Horseshoe kidney (HSK) is a congenital disorder that is usually asymptomatic, but that increases the risks of kidney stones and infectious disease. However, renal outcomes such as end-stage renal disease (ESRD) in patients with HSK remain unclear.

METHODS

In total, 146 patients with HSK (age of ≥20 years) from two tertiary hospitals were included in this study. Control individuals who underwent medical check-ups were selected by matching for age, sex, serum creatinine level, hypertension and diabetes. The hazard ratios (HRs) for the risks of ESRD and all-cause mortality were calculated after adjustment for multiple variables.

RESULTS

The proportions of HSK-related complications for obstruction, kidney stones, urinary tract infection and urogenital cancer were 26, 25, 19 and 4%, respectively. During the median follow-up period of 9 years (maximum 32 years), the incidence of ESRD was 2.6/10 000 person-years. The risk of ESRD in patients with HSK was higher than in control individuals [adjusted HR = 7.6; 95% confidence interval (CI) 1.14-50.47]. All-cause mortality did not differ between the two groups (adjusted HR = 0.6; 95% CI 0.08-4.29).

CONCLUSIONS

Patients with HSK are at risk of ESRD, which may be attributable to the high prevalence of complications. Accordingly, these patients should be regarded as having chronic kidney disease and require regular monitoring of both kidney function and potential complications.

Congenital Anomalies of the Upper Urinary Tract: A Comprehensive Review

The upper urinary tract is the most common human system affected by congenital anomalies. Congenital anomalies of the kidneys and ureters comprise a wide spectrum of disorders ranging from simple variants with no clinical significance to complex anomalies that may lead to severe complications and end-stage renal disease. They may be classified as anomalies of renal form, which are subclassified as structural anomalies (eg, persistent fetal lobulation, hypertrophied column of Bertin, and dromedary hump) and fusion anomalies (eg, horseshoe kidney and pancake kidney); anomalies of renal position (eg, renal malrotation, simple renal ectopia, and crossed renal ectopia) and renal number (eg, renal agenesis and supernumerary kidney); and abnormalities in development of the urinary collecting system (eg, pyelocaliceal diverticulum, megacalycosis, ureteropelvic junction obstruction, duplex collecting system, megaureter, ectopic ureter, and ureterocele). US is usually the first imaging modality used because of its low cost, wide availability, and absence of ionizing radiation. Intravenous urography and voiding cystourethrography are also useful, mainly for characterization of the collecting system and vesicoureteral reflux. However, intravenous urography has been replaced by CT urography and MR urography. These imaging methods not only allow direct visualization of the collecting system but also demonstrate the function of the kidneys, the vascular anatomy, adjacent structures, and complications. Comprehension of congenital anomalies of the upper urinary tract is crucial for an accurate diagnosis and correct management. The authors discuss the spectrum of these anomalies, with emphasis on embryologic development, imaging findings, clinical manifestations, and complications. Online supplemental material is available for this article. ^©RSNA, 2021.

Accessory renal arteries involved in atherosclerotic occlusive disease at the aortic bifurcation

Accessory renal arteries (ARAs) are embryonic remnants found in more than one-third of patients and occurring bilaterally in 10% of the population. Very few reports have documented such vessels arising near or at the level of the aortic bifurcation. Furthermore, the presence of ARAs has yet to be described in the context of atherosclerotic disease. Here, we present a unique case of large bilateral ARAs originating above the aortic bifurcation concurrent with symptomatic aortoiliac atherosclerotic disease. We highlight the embryologic and clinical significance of these vessels as well as discuss their potential role in accelerating atherosclerotic disease processes.

Kidney segmentation in neck-to-knee body MRI of 40,000 UK Biobank participants

The UK Biobank is collecting extensive data on health-related characteristics of over half a million volunteers. The biological samples of blood and urine can provide valuable insight on kidney function, with important links to cardiovascular and metabolic health. Further information on kidney anatomy could be obtained by medical imaging. In contrast to the brain, heart, liver, and pancreas, no dedicated Magnetic Resonance Imaging (MRI) is planned for the kidneys. An image-based assessment is nonetheless feasible in the neck-to-knee body MRI intended for abdominal body composition analysis, which also covers the kidneys. In this work, a pipeline for automated segmentation of parenchymal kidney volume in UK Biobank neck-to-knee body MRI is proposed. The underlying neural network reaches a relative error of 3.8%, with Dice score 0.956 in validation on 64 subjects, close to the 2.6% and Dice score 0.962 for repeated segmentation by one human operator. The released MRI of about 40,000 subjects can be processed within one day, yielding volume measurements of left and right kidney. Algorithmic quality ratings enabled the exclusion of outliers and potential failure cases. The resulting measurements can be studied and shared for large-scale investigation of associations and longitudinal changes in parenchymal kidney volume.

Presacral Anatomy in Women With a Horseshoe Kidney

OBJECTIVE

Horseshoe kidney (HSK) is the most common renal fusion defect that can alter vascular and upper urinary tract anatomy. Anatomic variations in the presacral space can make surgical dissection very challenging. The aim of this study was to characterize presacral anatomy in women with HSK.

METHODS

Large academic centers' database was queried to identify imaging studies in adult women with HSK. Available multiplanar computed tomography and magnetic resonance imaging images were reviewed, and relevant vascular and upper urinary tract anatomy was measured and compared with published normal values. Study population was compared with the normal controls using Student t test, χ test, or Fisher exact test as appropriate.

RESULTS

One hundred seventy-eight women were identified initially, and 20 confirmed to have HSK on imaging. The mean ± SD age was 54.5 ± 16.9 years, and body mass index was 27.3 ± 7.5 kg/m. Women with HSK had a narrower angle of aortic bifurcation (39.1 ± 18.7 degrees vs 55.6 ± 4.5 degrees, P = 0.014); the right ureter was closer to midline (22.9 ± 8.8 mm vs 32.3 ± 1.2 mm, P < 0.001) when compared with normal controls anatomy. In 40% of women with HSK, the bifurcation of the vena cava was below the level of L5 in contrast to the 8% in the normal population (P < 0.001). In 60% of women with HSK, the inferior pole of the kidney was at or below L5.

CONCLUSIONS

Ureteral, renal, and vascular anatomic alterations in women with HSK may make presacral surgical anatomy challenging by obscuring the anterior longitudinal ligament anchoring point. Preoperative imaging is warranted to determine the feasibility of female pelvic reconstructive surgery in HSK patients.

Coexistence of a rare type of ectopic kidney with atypical renal vasculature

Knowledge of anatomical anomalies is significant for all specialists in clinical practice and may prevent serious complications following medical procedures. This report presents the rare crossed fused renal ectopia (CFRE) with atypical renal vasculature in cadaver of a 68-year-old man. The ectopic kidney was located on right side with four renal veins, three renal arteries, two ureters, where one of them is double. The embryological background, as well as the potential clinical significance of this morphological variation, is discussed. An interventional radiological and surgical procedure should be appropriately implemented to treat anomalies of vessels and CFRE.

Against the Odds: Management of Ureteral Calculus in Patient With Crossed Fused Renal Ectopia

Crossed fused renal ectopia (CFRE) is a rare congenital abnormality of the urinary tract where the kidneys are fused on one side, while the ureter of the ectopic kidney crosses the midline with the normal entrance in the bladder on the contralateral side. Congenital anomalies are associated with a stone formation whose management represents a real challenge. To our knowledge, we report the second case of CFRE associated with ureteral stone, which has been successfully resolved with Extracorporeal Shockwave Lithotripsy (ESWL) and the first of its kind where a sufficient degree of stone disintegration has been achieved after a single session with a complete stone clearance during the follow-up. Radiological examination showed an inferior type of CFRE with stone in the proximal part of the ureter of the upper kidney. ESWL is an acceptable and effective treatment option in CFRE patients due to the minimally invasive approach, potentially high stone-free rate, and rare complications.

A Horseshoe Kidney With Solid Mass: A Case Report

Sonography can be used to detect horseshoe kidneys. Sonographic findings for horseshoe kidney commonly include an isthmus connection occurring anterior to the aorta and just inferior to the inferior mesenteric artery. This anomaly can occur with or without complications. Each kidney is associated with its separate collecting system, leading to increased risk for complications. This case study describes the importance of identifying a horseshoe kidney, isthmus, and blood supply to ensure prompt intervention if needed. A case report of a horseshoe kidney with a solid mass, in the isthmus, is provided.

Incidentally detected pancake kidney: a case report

Background

Congenital anomalies of the urinary system are very common and have extremely varied presentation. Among them, the most rarely found structural anomaly is the pancake kidney. When both kidneys are fused along their medial surfaces to form a round-shaped single renal mass, it is termed as pancake kidney. In this case report, a pancake kidney was incidentally detected in a girl. The majority of individuals who have pancake kidney are usually asymptomatic but surgeons should be aware of coexisting malformation of other organs and its potential risk of developing malignancy.

Case presentation

A 12-year-old Bengali girl presented to our out-patient department with mild, dull aching, lower abdominal pain and dysuria. She had no history of fever, hematuria, menstrual abnormality, pelvic inflammatory disease, or trauma. Urine examination showed traces of albumin and 10–12 pus cells/high-power field. She had normal kidney function test but a digital X-ray of her kidney, ureter, and bladder region failed to demonstrate bilateral renal tissue shadows. Ultrasonography of her whole abdomen showed normal intra-abdominal organs except for empty bilateral renal fossa. A multi-detector computed tomography scan of her whole abdomen revealed one round-shaped mass measuring approximately 9 cm (vertical) × 10 cm (horizontal) in the pelvic cavity. That mass was finally identified as a pancake kidney. She was prescribed antibiotics based on urine culture and sensitivity test that cured her symptoms. She was advised to follow-up regularly in our out-patient department to evaluate her kidney function and to rule out any neoplastic change.

Conclusions

This condition can be managed conservatively, if the individual remains asymptomatic, by regular monitoring of renal function. Surgeons should remain alert for the development of infections, any obstructive manifestations leading to calculus formation, and any malignant changes. The individual should be careful in avoiding trauma to low-lying pelvic kidney. Extensive surgeries should be avoided and only selective procedures should be done so that the patient may lead a normal lifestyle.

Traumatic Blunt Force Renal Injury in a Diseased Horseshoe Kidney with Successful Embolization to Treat Active Bleeding: A Case Report and Literature Review

Background

Blunt force injuries in patients with preexisting kidney disease account for 19% of all kidney injuries, suggesting that diseased kidneys are more vulnerable than normal kidneys. When a horseshoe kidney (a rare anomaly: prevalence of 0.2%) is injured, treatment is challenging, especially when nonoperative management is desired. In high-grade blunt force normal kidney injury, nonoperative management has high succession rate (94.8%) with kidney-related complication (13.6%). Surgical reconstruction and preservation of a damaged horseshoe kidney is difficult because of variations in its vascular anatomy. We report successful nonoperative management of a blunt horseshoe kidney injury with active bleeding and review previous outcomes and complications. Case Presentation. A 57-year-old man had a head-on collision motorcycle road traffic accident. On arrival, blood pressure was 90/60 mmHg, pulse rate 140 bpm, and clear yellow urine output 200 ml. The patient was transiently responsive to fluid and blood component. Whole body computed tomography showed a high-volume retroperitoneal hematoma and multiple-lacerated lower pole of the kidney, compatible with preexisting horseshoe kidney disease with active contrast-enhanced extravasation from the accessory right renal artery. Embolization was performed. Renal function, transiently impaired after embolization, normalized on day 3. An infected hematoma found on day 7 was successfully controlled with antibiotics. His recovery was uneventful. At the 6-month follow-up, his serum creatinine level had returned to normal. The average age of blunt force horseshoe kidney injury is 31.75 years and occurred more common in male (87.5%).

Conclusion

Diseased horseshoe kidneys are prone to injury even with low-velocity impact such as a road traffic accident speed < 15 km/h. Embolization is considered the first choice for management, with its high clinical success rate leading to less need for surgical repair. Not removing a hematoma is likely to result in complications. If embolization fails to stop bleeding, life-saving surgical exploration should be mandated.

Case Report of a Pelvic Crossed Fused Renal Ectopic Kidney

Herein we present a case of a horseshoe kidney with crossed fused renal ectopia. Both of these pathologies are congenital anomalies; however, to date, there are few cases that present with both. In this case, discovered during routine dissection, the fused kidney was mostly left-sided and very low in the pelvis. No renal artery arose from the right wall of the abdominal aorta, and the right renal vein drained into the lower part of the inferior vena cava (IVC) where the right and left common iliac veins joined. It is essential for clinicians and surgeons to understand these types of congenital anomalies, as they could impact patient care.

Crossed Renal Ectopia with a Fused Supernumerary Kidney

Crossed fused renal ectopia and the presence of a supernumerary kidney are both rare congenital variants that are often asymptomatic but may be associated with other developmental anomalies. Here we present a case of a 20-year-old male with a known diagnosis of crossed fused renal ectopia as well as a history of imperforate anus and tethered spinal cord treated in infancy. He presented to the emergency room with symptoms of flank pain, and a noncontrast computed tomography (CT) scan revealed a 4-mm stone in the distal left ureter. CT scan also revealed that the patient's right kidney was not crossed and fused to the left kidney as previously believed, but rather it was crossed and fused to a supernumerary kidney abutting the inferomedial aspect of an orthotopic left kidney. This is a unique example of two rare coexisting renal anomalies not previously detected on a nuclear medicine renal scan and serial renal ultrasounds obtained earlier in the the patient's life.

Management of staghorn stones in special situations

Staghorn stones have always been a challenge for urologists, especially in some special situations, such as horseshoe kidney, ectopic kidney, paediatric kidney, and solitary kidney. The treatment of these staghorn stones must be aggressive because they can lead to renal function loss and serious complications. The gold-standard management for staghorn stones is surgical treatment with the aim of clearing the stones and preserving renal function. Treatment methods for staghorn stones have developed rapidly, such as extracorporeal shock wave lithotripsy, retrograde intrarenal surgery, percutaneous nephrolithotomy and laparoscopy and open surgery. Whether the standard procedures for staghorn stones can also apply to these stones in special situations is still not agreed upon. The decision should be made individually according to the circumstances of the patient. In this review, we evaluates the previous studies and comments on the management of staghorn stones under special situations in the hope of guiding the optimal choice for urologists.

Robot-assisted laparoscopic partial nephrectomy for horseshoe kidney: A case report

INTRODUCTION

Horseshoe kidney has unique anatomical features, such as a complex blood supply. We report a patient with renal cell carcinoma in a horseshoe kidney, who underwent tumor resection by robot-assisted laparoscopic partial nephrectomy based on preoperative three-dimensional computed tomography.

CASE PRESENTATION

A 66-year-old man was referred to our hospital with a 2-cm enhancing mid-pole mass in the left moiety of a horseshoe kidney. The clinical diagnosis was renal cell carcinoma cT1aN0M0 (R.E.N.A.L. nephrometry score: 1 + 2 + 3 + 3 = 9p). Robot-assisted laparoscopic partial nephrectomy was performed with selective clamping based on reconstructed three-dimensional images. The warm ischemia time was 13 min. Pathologic examination confirmed a diagnosis of pT1a clear cell renal cell carcinoma with negative surgical margins. At 6 months postoperatively, computed tomography showed no local recurrence or metastasis and renal function was intact.

CONCLUSION

Robot-assisted laparoscopic partial nephrectomy with preoperative three-dimensional computed tomography may have advantages for resection of tumors in patients with horseshoe kidney.

Crossed fused renal ectopia in children: a review of clinical profile, surgical challenges, and outcome

INTRODUCTION

Crossed fused renal ectopia is a rare congenital malformation, wherein both kidneys are present unilaterally, with the ureter of the crossed kidney opening into the bladder on the contralateral side. It has varied presentation from incidental detection to renal impairment. In this largest series of crossed fused renal ectopia, the authors assessed the clinical profile of these children and also attempted to shed light on the challenges in the surgical management.

METHODS

It is a retrospective study conducted from January 2009 to July 2018, among patients evaluated for crossed fused ectopia, in the Department of Pediatric Surgery, Christian Medical College, Vellore. Electronic medical records of 36 children were reviewed. Imaging modalities and operative interventions were recorded. Results were analyzed.

RESULTS

A total of 36 children were found to have crossed fused ectopia, with male preponderance. Most children presented within one year of age with urinary tract infection being the commonest cause. The most common associated anomaly was anorectal malformation. Ultrasound abdomen and pelvis, micturating cystourethrogram, and radionucleotide scans were the imaging modalities preferred for diagnosis and follow-up. Left-to-right ectopia was more common with inferior ectopic variant being the most common. The predominant urological problems include pelviureteric junction obstruction, vesicoureteric junction obstruction, and vescioureteric reflux. Ureteric re-implant was the most common surgery performed followed by pyeloplasty. Pelvi-pelvostomy, uretero-ureterostomy, bladder augment with Mitrofanoff, and other procedures were performed for select cases.

CONCLUSION

Crossed fused renal ectopia is a challenging entity which requires individualized management plans based on the predominant urological anomaly and the functional status. Surgical options are diverse and are guided toward the symptomatic urological problem with focus on preserving the renal function. The long-term prognosis is good in these children.

A Case of Incomplete Removal of Horseshoe Kidney by Laparoscopic Nephrectomy in an Adult Leading to Urinary Leak: An Eye Opener

Horseshoe kidney is a common congenital fusion anomaly of the kidneys. It poses a challenge to surgeon because of its very variable anatomy in terms of location and lie, fusion, pelvicalyceal system, and the renal vessels. Here we describe a case of laparoscopic nephrectomy in a horseshoe kidney complicated by incomplete removal because of not realizing the lower and medial extent of pelvicalyceal system across midline to the contralateral side leading to persistent urine leak. The relevant anatomy and the necessary precautions to prevent such complication have been discussed.

Deployment of a Resuscitative Endovascular Balloon Occlusion of the Aorta Device in a Case of Gunshot Wound Injury to a Horseshoe Kidney

A horseshoe kidney (HSK) is a urological malformation that is typically found incidentally after a traumatic injury due to its asymptomatic nature. We present a 25-year-old male with multiorgan injuries secondary to blunt abdominal trauma caused by a gunshot wound. We report the courses of action taken that led to the identification of the HSK and other associated intra-abdominal injuries and the subsequent surgical management. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an improving minimally invasive technique that was used to control hemorrhage in the early preoperative stages and during surgical repair of the injuries. Multiorgan injuries that involve an HSK are uncommon. Our interest in the case relies on the rarity and unique aspects of the injuries and the recovery of the patient following the use of REBOA.

The level of origin of renal arteries in horseshoe kidney vs. in separated kidneys: CT-based study

Purpose

Horseshoe kidney is a rare congenital anomaly with potential clinical implications. The aim of this study was to determine the number of renal arteries and veins and the level at which the arteries branched off their parental vessels in individuals with horseshoe kidney (HSK) and in persons with separated kidneys (SK).

Materials and methods

The analysis included computed tomography angiography studies of 331 patients (83 HSK and 248 SK). The number of renal vessels and diameters of renal arteries were determined, along with the level at which they branched in relation to other ramifications (four groups of origin were proposed) and their entrance of the vessels to the kidney.

Results

Number of renal arteries in HSK group was 4.57 ± 1.39 per patient and 2.4 ± 0.43 in SK group (p < 0.0001). The distribution of branching level of renal arteries in HSK group was: I group ~ 57%, II group ~ 27%, III group ~ 15% and IV group < 1%, whereas in SK group the distribution was respectively: I group ~ 99%, II group < 1%, III and IV group − 0% (p = 0.0001). In HSK group, diameter of renal arteries branching above the IMA was 4.61 ± 1.58 mm, as compared with 3.96 ± 1.34 mm for the arteries branching below (p = 0.0004). Number of veins was 566 in SK group (87.70% of kidneys were supplied by single vein) and 323 in HSK group (9.64% kidneys were supplied by two veins) (p < 0.0001).

Conclusion

In HSK group, renal arteries significantly more often branch off their parental vessels below the origin of IMA and such vessels are usually smaller.

Percutaneous cryoablation for stage T1b renal cell carcinoma in a patient with horseshoe kidney

We report the first case of percutaneous cryoablation (PCA) for stage T1b renal cell carcinoma (RCC) in a horseshoe kidney (HK). A 76-year-old man with an HK underwent computed tomography-guided PCA for RCC measuring 42 mm (stage T1b) in diameter. Although transcatheter embolization before the PCA and hydrodissection were required to avoid complication and incomplete ablation, PCA was successfully performed without complication. The complete ablation was confirmed on computed tomography images 1 month after the procedure. There was no recurrence or metastasis during 2 years of follow-up. We believe this is the first report of PCA for stage T1b RCC in a patient with HK. This technique can be performed without regard to tumor size and location and may be considered as a treatment option to avoid complex surgery.