Unilateral renal cortical necrosis.

A 51-year-old woman presented to her local emergency department with acute onset right-sided flank pain and nausea. Her blood results on admission were largely unremarkable aside from leucocytosis and neutrophilia. Two days after admission, she developed the following: stage 3 AKI with oliguria, anaemia, thrombocytopenia, and acute derangement of liver function tests. A computed tomography of the kidney ureter bladder demonstrated a right-sided 4 mm obstructing vesicoureteric junction stone with associated hydronephrosis and hydroureter. She was transferred to a tertiary care centre; gram negative sepsis was confirmed with a Proteus on blood culture and laboratory findings were in keeping with DIC. She was treated with Tazobactam/Piperacillin and intravenous fluids. In addition, further imaging showed improving right-sided hydronephrosis and left renal cortical necrosis. The aetiology of this presentation was sepsis complicated by disseminated intravascular coagulation. The coagulopathy likely contributed to the unilateral renal cortical necrosis. Cortical necrosis usually affects both kidneys, and is typically a complication of sepsis, shock, or obstetrical trauma. To our knowledge, there are only 2 reported cases of unilateral renal cortical necrosis and contralateral hydronephrosis with renal colic and septic shock. Potential pathogenetic mechanisms are discussed.

Duplex Kidney in Adults: a Systematic Review of the Literature.

PURPOSE OF REVIEW: In this study, we describe a rare case of a male with a duplex renal collecting system with ectopic ureter insertion into the prostate who presented with sepsis and required urgent laparoscopic radical nephrectomy. This study offers urologists and emergency care practitioners a great overview of the variety of manifestations, anatomic differences, and therapeutic approaches for similar patients. RECENT FINDINGS: modified reconstructive strategy could be a method of choice when addressing particular anatomies, such as incomplete duplex kidneys with ureteropelvic junction obstruction in both upper and lower poles when the obstruction is close to the confluence of the two ureters. There is a spectrum of acute presentations and management strategies in adult patients with duplex collecting systems. The majority of patients presenting with obstruction and infection are managed surgically with hemi-nephrectomy; stable patients who present with less extensive anomalies were managed conservatively or with ureteral dilatation or deroofing.

Ahnak is required to balance calcium ion homeostasis and smooth muscle development in the urinary system.

BACKGROUND: Various renal abnormalities, including hydronephrosis, polycystic kidney disease, and hydroureter, have been reported, and these abnormalities are present in DiGeorge syndrome, renal dysplasia, and acute kidney failure. Previous studies have shown that various genes are associated with renal abnormalities. However, the major target genes of nonobstructive hydronephrosis have not yet been elucidated. RESULTS: We examined neuroblast differentiation-associated protein Ahnak localization and analyzed morphogenesis in developing kidney and ureter. To investigated function of Ahnak, RNA-sequencing and calcium imaging were performed in wild type and Ahnak knockout (KO) mice. Ahnak localization was confirmed in the developing mouse kidneys and ureter. An imbalance of calcium homeostasis and hydronephrosis, which involves an expanded renal pelvis and hydroureter, was observed in Ahnak KO mice. Gene Ontology enrichment analysis on RNA-seq results indicated that 'Channel Activity', 'Passive Transmembrane Transporter Activity' and 'Cellular Calcium Ion Homeostasis' were downregulated in Ahnak KO kidney. 'Muscle Tissue Development', 'Muscle Contraction', and 'Cellular Calcium Ion Homeostasis' were downregulated in Ahnak KO ureter. Moreover, peristaltic movement of smooth muscle in the ureter was reduced in Ahnak KO mice. CONCLUSIONS: Abnormal calcium homeostasis causes renal disease and is regulated by calcium channels. In this study, we focused on Ahnak, which regulates calcium homeostasis in several organs. Our results indicate that Ahnak plays a pivotal role in kidney and ureter development, and in maintaining the function of the urinary system.

Value of detected hydronephrosis and hydroureter on ultrasound for detecting a ureteral stone: a retrospective study.

To investigate the predictive value of hydronephrosis and hydroureter in the detection of ureteral stones using ultrasound, a total of 366 patients suffering from ureteral stones confirmed by ultrasound, computed tomography (CT) and their follow-up treatments were consecutively collected. All the included patients underwent systematic ultrasound scanning of the kidney and ureter. The hydronephrosis and hydroureter in each patient were measured using a digital caliper. Then, receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff values for hydronephrosis and hydroureter to predict a ureteral stone's location and size. The hydronephrosis, hydroureter, and stone size measurements showed good interobserver agreement (P < 0.001). Using the lower border of the sacroiliac joint as a demarcation point, we found larger widths of hydronephrosis and hydroureter in the proximal ureteral stone group than in the distal ureteral stone group (P < 0.001). Additionally, 10.9 mm and 5.9 mm were identified as optimal cutoff values for predicting a distal position (P < 0.001), with no significant difference in their predictive value (P > 0.05). Similar comparisons between groups based on size stratification revealed no significant difference in hydronephrosis between the > 5 mm group and the ≤ 5 mm group. However, the hydroureter was larger in the > 5 mm group than in the ≤ 5 mm group after identifying 6 mm as the best cutoff (P =0.004). In summary, the ultrasound measurement of hydronephrosis and hydroureter may predict the position and size of a possible ureteral stone in patients with colic symptoms.

Ureteral Obstruction Promotes Ureteral Inflammation and Fibrosis.

BACKGROUND: Hydronephrosis and renal impairment may persist even after relieving an obstruction, particularly in cases of chronic obstruction. Obstruction can cause fibrotic changes of the ureter, potentially contributing to long-term kidney damage. OBJECTIVE: To characterise pathophysiological changes of obstructed ureters with focus on inflammatory responses triggering fibrosis and potential impairment of ureteral function. DESIGN, SETTING, AND PARTICIPANTS: Eighty-eight mice were randomly assigned to unilateral ureteral obstruction (UUO) for 2 d, UUO for 7 d, and UUO for 7 d followed by 8 d of recovery, or a control group (no prior surgical intervention). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Peristaltic rate was determined over 2 min by direct visualisation with a microscope, while hydronephrosis was assessed by ultrasound. Obstructed and contralateral ureters were harvested, and underwent histopathological evaluation. We quantified 44 cytokines/chemokines, and five matrix metalloproteases using Luminex technology. Cell composition was characterised via immunofluorescence. Statistical significance was assessed using Welch analysis of variance, Kruskal-Wallis test, and Dunnett's T3 multiple comparison test. RESULTS AND LIMITATIONS: Obstruction resulted in hydronephrosis and significantly impaired peristalsis. Marked fibrosis was observed in lamina propria, muscle layer, and adventitia. Connective tissue in obstructed ureters showed hyperaemia and leucocyte infiltration. Unsupervised hierarchical clustering demonstrated different cytokine/chemokine patterns between groups. Ureters obstructed for 7 d followed by recovery were notably different from other groups. Inflammatory cytokines, chemoattractants, and matrix metalloproteases increased significantly in obstructed ureters. Contralateral unobstructed ureters showed significantly increased levels of chemokines and matrix metalloproteases. Immunofluorescence confirmed activation of T cells, Th1 and Th2 cells, and M1 macrophages in obstructed and contralateral ureters, and a shift to M2 macrophages following prolonged obstruction. CONCLUSIONS: Ureteral obstruction triggers severe inflammation and fibrosis, which may irreversibly impair ureteral functionality. Function of the unobstructed contralateral ureter may be regulated by a systemic immune response as a result of the obstruction. PATIENT SUMMARY: Here, we studied in more detail the way the ureter responds to being blocked. We conclude that a strong immune response is activated by the blockage, leading to changes in the structure of the ureter possibly impacting function, which may not be reversible. This immune response also spreads to the opposite ureter, possibly allowing it to change its function to compensate for the reduced functionality of the blocked ureter.

Orthotopic ureterocele with concurrent ureteral urothelial carcinoma in a dog.

A ureterocele is a rare congenital anomaly with cystic dilation of the terminal segment of the ureter entirely within the bladder (orthotopic) or associated with ectopic ureter (ectopic). Its aetiology has not been fully clarified; however, it may involve genetic or acquired factors. Urothelial carcinoma (UC) is the most common type of canine urinary tract neoplasm, among which over 90% of cases are invasive. The non-papillary (flat) non-infiltrating form accounts for a very small percentage of canine UCs and is considered carcinoma in situ (CIS). The neoplastic cells of CIS remain within the ureteral mucosa and do not breach the basement membrane. UCs originating from the canine ureter are extremely rare, and no report of a ureteral UC concurrently occurring with a ureterocele has been reported. A 7-year-old castrated male Maltese dog weighing 3.5 kg was referred with a 2-week history of lethargy, anorexia, pollakiuria and intermittent panting. The dog underwent open surgery for removal of bladder calculi 2 years prior, and at the time of the surgery, no other urinary system abnormalities were identified. Ultrasonographic and computed tomographic scans revealed a severely enlarged right kidney and ureter with a ureterocele on the ipsilateral side. A diagnosis of an orthotopic ureterocele causing hydronephrosis and hydroureter was established. Complete nephroureterectomy and ureterocelectomy using the marsupialisation technique were performed. The postoperative histological examination of the excised tissues showed a multifocal carcinoma in situ (non-papillary non-infiltrating UC) in the proximal ureter and a fluid-filled kidney with a thin rim of fibrotic renal tissue. No neoplastic changes were observed in the ureterocele tissue. Postoperatively, the dog recovered rapidly without complications except temporary urinary incontinence, and no evidence of tumour recurrence was detected by ultrasonography performed 6 months after surgery. This case report describes the first case of a dog with an orthotopic ureterocele and ureteral UC, which occurred concurrently at the ipsilateral side of the ureter. The condition was successfully managed with a nephroureterectomy and partial ureterocelectomy.

Hypertensive Cardiomyopathy as a Sequel to Hydronephrosis Induced by Transitional Cell Carcinoma.

A 10-year-old female Griffon dog was presented for evaluation due to a 5-month history of hematuria and systemic hypertension. Thoracic auscultation detected a grade II/VI left apical systolic murmur. Abdominal ultrasound revealed the presence of a heterogeneous mass at the trigonal area of the urinary bladder, extending to the left ureter cranially and caudally toward the bladder's neck. Marked left hydronephrosis and hydroureter were detected as well as mild right hydronephrosis. Cytological examination of urine sediment confirmed the presence of transitional cell carcinoma. Echocardiography disclosed marked left ventricular concentric hypertrophy, which likely developed as a consequence of systemic hypertension induced by the bilateral hydronephrosis due to bladder transitional cell carcinoma.

A case of congenital ureteral atresia causing rare upper and lower urinary tract manifestations in a puppy: a case report.

BACKGROUND: Ureteral atresia is the congenital absence of a ureteral opening, resulting in a blind-ended ureter that fails to terminate at the urinary bladder. Consequently, severe hydroureter and hydronephrosis occur ipsilateral to the atresic ureter. However, hydronephrosis contralateral to severe hydroureter, although reported in humans, is not documented in the dog. Additionally, ureteral atresia has not been reported as a cause for lower urinary tract signs directly related to extramural urinary bladder compression. This report aims to describe these unique manifestations of this congenital urinary tract disease, as well as follow-up findings after successful treatment. CASE PRESENTATION: A 4-month-old male Husky puppy was evaluated for pollakiuria, stranguria, and urine dribbling of 1-month duration. During the physical examination, a mass was palpated in the mid-abdomen. Diagnostic imaging and cystoscopy findings were diagnostic for right-sided ureteral atresia with secondary hydroureter and hydronephrosis. The severe right hydroureter caused lower urinary tract signs and contralateral hydronephrosis secondary to regional compression of the left distal ureter and urinary bladder. A right-sided ureteronephrectomy was performed, resolving the stranguria and pollakiuria. Significant reduction in the contralateral (left) hydronephrosis also occurred. CLINICAL RELEVANCE: Ureteral atresia should be considered as a differential diagnosis for lower urinary tract signs and/or bilateral hydronephrosis in a young dog. Reporting this case expands our knowledge of congenital lower urinary tract disease and the etiology of their manifestations in dogs. Surgical resolution of the congenital ureteral abnormality can result in preservation of renal function in the contralaterally obstructed kidney.

Minimal renal pelvis dilation in cats diagnosed with benign ureteral obstruction by antegrade pyelography: a retrospective study of 82 cases (2012-2018).

OBJECTIVES: The aim of the study was to describe renal pelvis (RP) and ureteral ultrasonographic measurements in a population of cats with confirmed benign ureteral obstruction (UO) by antegrade pyelography. The secondary objective was to further describe clinical findings associated with minimally dilated obstructed kidneys in an attempt to better understand its occurrence. METHODS: Retrospective case series of cats diagnosed with benign UO were confirmed by antegrade pyelography. Medical records were reviewed and signalment, diagnostic imaging results, serum creatinine (SCr) concentration and urine culture results were recorded. Each obstructed kidney was categorized into two groups: group 1 included all RP measurements ⩽4 mm and group 2 included all RP measurements >4 mm. RESULTS: A total of 82 cats with 114 obstructed ureters met the inclusion criteria. Fifty (61%) cats had a unilateral UO and 32 (39%) had a bilateral UO. Thirty (26%) kidneys were included in group 1 while 84 (74%) were included in group 2. Nine (8%) kidneys had an RP dilation ⩽2 mm. Median RP and ureteral diameters were 6.6 mm (range 1.1-37.0 mm) and 3.2 mm (range 0.0-11.0 mm), respectively. RP size correlated positively with ureteral diameter in the study population (P <0.0001), but not in group 1 when analyzed separately (P = 0.47). UO was secondary to stones in 80 (70%) ureters. Seventeen (21%) cats had a positive urine culture. At admission, 79 (96%) cats were azotemic with a median preoperative SCr concentration of 444 µmol/l (range 108-1326 µmol/l). The mean (95% confidence interval [CI]) preoperative SCr concentration was significantly higher in group 1 (762 µmol/l [498-1165 µmol/l]) than in group 2 (409 µmol/l [333-502 µmol/l]). RP size in the two groups correlated negatively with preoperative SCr concentration (P = 0.0002). CONCLUSIONS AND RELEVANCE: Feline UO may be associated with minimal RP dilation and the severity of RP and ureteral dilation can be highly variable. Absence of significant RP dilation does not rule out UO in cats.

ACR Appropriateness Criteria® Antenatal Hydronephrosis-Infant.

Antenatal hydronephrosis is the most frequent urinary tract anomaly detected on prenatal ultrasonography. It occurs approximately twice as often in males as in females. Most antenatal hydronephrosis is transient with little long-term significance, and few children with antenatal hydronephrosis will have significant obstruction, develop symptoms or complications, and require surgery. Some children will be diagnosed with more serious conditions, such as posterior urethral valves. Early detection of obstructive uropathy is necessary to mitigate the potential morbidity from loss of renal function. Imaging is an integral part of screening, diagnosis, and monitoring of children with antenatal hydronephrosis. Optimal timing and appropriate use of imaging can reduce the incidence of late diagnoses and prevent renal scarring and other complications. In general, follow-up neonatal ultrasound is recommended for all cases of antenatal hydronephrosis, while further imaging, including voiding cystourethrography and nuclear scintigraphy, is recommended for moderate or severe cases, or when renal parenchymal or bladder wall abnormalities are suspected. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Endometriosis and the Urinary Tract: From Diagnosis to Surgical Treatment.

We aim to describe the diagnosis and surgical management of urinary tract endometriosis (UTE). We detail current diagnostic tools, including advanced transvaginal ultrasound, magnetic resonance imaging, and surgical diagnostic tools such as cystourethroscopy. While discussing surgical treatment options, we emphasize the importance of an interdisciplinary team for complex cases that involve the urinary tract. While bladder deep endometriosis (DE) is more straightforward in its surgical treatment, ureteral DE requires a high level of surgical skill. Specialists should be aware of the important entity of UTE, due to the serious health implications for women. When UTE exists, it is important to work within an interdisciplinary radiological and surgical team.

Primary Ureteral Hemangiosarcoma in a dog.

BACKGROUND: Primary ureteral neoplasia in dogs is extremely rare. To the best of the authors' knowledge, this is the second documented case of a primary ureteral hemangiosarcoma. This case report describes the clinical and pathological findings of a primary distal ureteral hemangiosarcoma. CASE PRESENTATION: A 12-year-old spayed female goldendoodle was presented with a history of polyuria and weight loss. Abdominal radiographs revealed a large cranial abdominal mass. Abdominal ultrasound and computed tomography (CT) identified a left sided distal ureteral mass with secondary hydroureter and a left lateral hepatic mass with no evidence of connection or diffuse metastasis. A left ureteronephrectomy, partial cystectomy, and left lateral liver lobectomy were performed. Histopathology was consistent with primary ureteral hemangiosarcoma and a hepatocellular carcinoma. Adjunctive therapy including chemotherapy was discussed but declined. CONCLUSION: Due to its rarity, the authors of this case presentation believe that ureteral hemangiosarcoma should be included as a differential diagnosis when evaluating a ureteral mass. With the unknown, and suspected poor prognosis, routine monitoring with adjunctive therapy should be considered.

Feline abdominal ultrasonography: What's normal? What's abnormal? Renal pelvis, ureters and urinary bladder.

PRACTICAL RELEVANCE: Abdominal ultrasound plays a vital role in the diagnostic work-up of many cats presenting to general and specialist practitioners. Ultrasound examination of the urinary tract provides important information useful in the investigation of several conditions including ureteral obstruction and cystitis. CLINICAL CHALLENGES: Despite ultrasonography being a commonly used modality, many practitioners are not comfortable performing an ultrasound examination or interpreting the resulting images. Even for the experienced ultrasonographer, differentiating between incidental findings, such as lipid droplets in the bladder, and pathological changes can be challenging. AIM: This review, part of an occasional series on feline abdominal ultrasonography, discusses the ultrasonographic examination of the normal and diseased renal pelvis, ureters and urinary bladder. Aimed at general practitioners who wish to improve their knowledge of and confidence in feline abdominal ultrasound, this review is accompanied by high-resolution images and videos available online as supplementary material. Ultrasound examination of the kidneys and perinephric space was discussed in an article published in May 2020. EQUIPMENT: Ultrasound facilities are readily available to most practitioners, although the use of ultrasonography as a diagnostic tool is highly dependent on operator experience. EVIDENCE BASE: Information provided in this article is drawn from the published literature and the author's own clinical experience.

Fibroepithelial Polyp in a Child: A Rare Pathology of Upper Urinary Tract Obstruction.

Fibroepithelial polyp is a rare benign tumor of the urothelial system that originates from the mesoderm. Polyps are usually small and located in the upper urinary tract and ureteropelvic junction. However, in the pediatric population, such polyps are more common in the posterior urethra and will present with symptoms of urinary tract obstruction. Some will present with flank pain and hematuria, resembling symptoms of ureteric stones. In this case, we discuss a nine-year-old boy presenting with complaints of flank pain and hematuria for one year. Following laboratory and radiological investigations, the left ureter was dilated at the mid-lumbar region with an anteroposterior diameter of 2.3 x 0.6 cm and a left renal pelvis anteroposterior diameter of 2.2 cm. An ultrasound scan identified an intraluminal lesion suspected to be a fibroepithelial polyp. Management was carried out via retroperitoneal surgery with upper ureteral resection and end-to-end anastomosis. Postoperatively, the patient's symptoms improved, and a subsequent ultrasound scan and renal function test showed improvement of the left hydroureter and hydronephrosis.

Use of a shaving technique for surgical management of partial ureteral obstruction due to endometriosis.

OBJECTIVE: To illustrate the surgical management of advanced endometriosis causing extrinsic ureteral compression. DESIGN: Video description of the case, demonstration of the surgical technique, reevaluation at 14-year follow-up, and review of urogenital endometriosis. Patient provided consent for the video recording and publication. This surgical report with no identifying patient data was exempt from Institutional Review Board approval. SETTING: Tertiary referral center. PATIENT(S): A 42-year-old nulligravida with a known history of endometriosis presented with persistent pelvic pain and no other specific symptoms. She had previously undergone a diagnostic laparoscopy demonstrating advanced endometriosis involving multiple organs, including the urinary tract. She was referred to us for further surgical management. Preoperative intravenous pyelogram showed partial obstruction and constriction of a long portion of the midpelvic and distal left ureter with proximal hydroureter, consistent with extrinsic ureteral compression. INTERVENTION(S): The patient underwent operative video laparoscopy using a multipuncture technique, with enterolysis, extensive left ureterolysis, shaving of periureteral constrictive fibrosis and endometriosis, cystoscopy, and placement of left ureteral stent. MAIN OUTCOME MEASURE(S): There was extensive endometriosis and fibrotic adhesions involving the left pelvic sidewall. Proximal hydroureter was noted to the pelvic inlet secondary to severe periureteral fibrosis from the pelvic brim to the bladder meatus, with significant narrowing of the pelvic ureter. The endometriosis was resected using hydrodissection and shaving with a carbon dioxide laser. Histopathologic evaluation of the resection specimens confirmed endometriosis. RESULT(S): An intravenous pyelogram performed 4 weeks postoperatively revealed ureteral patency and resolving hydroureter, and her ureteral stent was removed. Annual renal ultrasounds for the subsequent 2 years were normal. Fourteen years later, she remained asymptomatic on no suppressive treatment. A follow-up intravenous pyelogram was performed and showed a normal urinary tract with bilateral ureteral patency and no recurrent strictures or hydroureter. CONCLUSION(S): In selected cases, conservative shaving of periureteral fibrotic endometriosis avoids ureteral resection and has acceptable outcomes.

Massive Bilateral Hydroureteronephrosis and End-Stage Renal Disease Ensuing From Chronic Schistosomiasis: A Case Report.

Globally, schistosomal infections affect over 200 million people resulting in the loss of 70 million disability-adjusted life years. In the sub-Saharan Africa region, where over 85% of the global schistosomal infections are found, it is estimated that about 120 million people become symptomatic, over 20 million have severe disease, and nearly 200 000 die every year. Renal impairment is a severe consequence of schistosomiasis occurring in about 6% of all infected individuals and in 15% of those with the hepatosplenic form. We present a case of massive bilateral hydroureteronephrosis and end-stage renal disease resulting from chronic schistosomiasis in a 38-year-old male of African origin. A 38-year-old male rice farmer of African origin presented with a history of elevated blood pressure, abdominal swelling, and reduced urinary output for about 10 months. Abdominal examination revealed an intraabdominal mass measuring 30 cm × 17 cm extending from the right hypochrondrium region downward to right inguinal outward to umbilicus crossing the midline. He had an estimated glomerular filtration rate of 3.9 mL/min, hemoglobin of 6.78 g/dL, and had multiple electrolyte abnormalities. A computed tomography intravenous urogram scan of the abdomen revealed hepatomegaly (18 cm), bilateral renal enlargement with hydroureteronephrosis, and multiple calcifications on the urinary bladder. A rectal biopsy isolated haematobium eggs and confirmed the diagnosis. Urinary schistosomiasis can have distressing effects on the urinary system in particular and survival prospects in general. In view of this, extensive evaluation of the genitourinary system is pivotal for timely diagnosis and prompt management particularly in residents of schistosoma-endemic communities presenting with obstructive uropathy.

Bilateral hydronephrosis and hydroureter associated with 21-22 weeks gestational age of cervical ectopic pregnancy: a case report.

Cervical ectopic pregnancy is a rare form of ectopic pregnancy. This incidence represents less than 1% of all ectopic pregnancies with reported incidence rates varying from 1:1,000 to 1:95,000 pregnancies. Cervical ectopic pregnancy is difficult to diagnose. Hydronephrosis and hydroureter have never been reported as complications of cervical ectopic pregnancy, and both are diagnosed after laparotomy. The potential morbidity, highlighted in this case study, demonstrates the importance of early diagnosis of a cervical ectopic pregnancy so that early intervention and treatment can be employed.

Homozygous noncanonical splice variant in LSM1 in two siblings with multiple congenital anomalies and global developmental delay.

Two siblings, one male and one female, ages 6 and 13 yr old, have similar clinical features of global developmental delay, multiple congenital anomalies affecting the cardiac, genitourinary, and skeletal systems, and abnormal eye movements. Whole-genome sequencing revealed a homozygous splice variant (NM_014462.3:c.231+4A>C) in LSM1 that segregated with the phenotype in the family. LSM1 has a role in pre-mRNA splicing and degradation. Expression studies revealed absence of expression of the canonical isoform in the affected individuals. The Lsm1 knockout mice have a partially overlapping phenotype that affects the brain, heart, and eye. To our knowledge, LSM1 has not been associated with any human disorder; however, the tissue expression pattern, gene constraint, and the similarity of the phenotype in our patients and the knockout mice models suggest it has a role in the development of multiple organ systems in humans.

Delayed onset of smooth muscle cell differentiation leads to hydroureter formation in mice with conditional loss of the zinc finger transcription factor gene Gata2 in the ureteric mesenchyme.

The establishment of the peristaltic machinery of the ureter is precisely controlled to cope with the onset of urine production in the fetal kidney. Retinoic acid (RA) has been identified as a signal that maintains the mesenchymal progenitors of the contractile smooth muscle cells (SMCs), while WNTs, SHH, and BMP4 induce their differentiation. How the activity of the underlying signalling pathways is controlled in time, space, and quantity to activate coordinately the SMC programme is poorly understood. Here, we provide evidence that the Zn-finger transcription factor GATA2 is involved in this crosstalk. In mice, Gata2 is expressed in the undifferentiated ureteric mesenchyme under control of RA signalling. Conditional deletion of Gata2 by a Tbx18cre driver results in hydroureter formation at birth, associated with a loss of differentiated SMCs. Analysis at earlier stages and in explant cultures revealed that SMC differentiation is not abrogated but delayed and that dilated ureters can partially regain peristaltic activity when relieved of urine pressure. Molecular analysis identified increased RA signalling as one factor contributing to the delay in SMC differentiation, possibly caused by reduced direct transcriptional activation of Cyp26a1, which encodes an RA-degrading enzyme. Our study identified GATA2 as a feedback inhibitor of RA signalling important for precise onset of ureteric SMC differentiation, and suggests that in a subset of cases of human congenital ureter dilatations, temporary relief of urine pressure may ameliorate the differentiation status of the SMC coat. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Multimodality imaging of primary ureteral hemangiosarcoma with thoracic metastasis in an adult dog.

A 12-year-old spayed female standard Poodle was presented for investigation of severe hematuria. Abdominal ultrasound and thoracic and abdominal computed tomography identified severe hydronephrosis due to an obstructive ureteral mass with no evidence of metastasis. Histological examination after nephrectomy and ureterectomy confirmed an obstructive ureteral hemangiosarcoma. Forty days after surgery, the dog was presented with severe dyspnea. Survey radiographs of the thorax revealed a severe diffuse nodular interstitial pattern. Postmortem histological examination revealed pulmonary metastasis of hemangiosarcoma.