Posterior nutcracker syndrome - a systematic review.

Posterior nutcracker syndrome (PNCS) is the entrapment of the left renal vein between the aorta and the vertebral column. Although uncommon, it is still an important diagnosis due to the high morbidity associated with the risk of secondary anaemia from haematuria, from long-term left renal vein hypertension, vascular thrombosis, and even blood clots in the urinary system. A literature search of PubMed and EMBASE databases was performed and 27 publications containing 27 cases were included for the final analysis. The following frequency of clinical signs and symptoms was noted: twenty-five patients had haematuria, 13 patients had flank pain, and two had hypertension. Overall, male-female distribution was balanced and there were more adult than paediatric (age < 18 years) patients. All symptoms of patients with conservative treatment were either well-controlled or under spontaneous resolution. Conservative management instead of surgical treatment should be preferred in most cases. Taken together, despite the low incidence of PNCS, its recognition and management are highly important. This systematic study explores the evidence base for conservative and medical options.

Endovascular Treatment of Nutcracker Syndrome.

BACKGROUND: Nutcracker syndrome, or mesoaortic compression of the left renal vein (LRV), with associated symptoms related to venous hypertension in the left kidney, is a rare entity that may result in severe symptoms requiring operative intervention. We report on 3 patients who presented with nutcracker syndrome, including one patient with a circumaortic LRV resulting in posterior nutcracker syndrome, who underwent successful endovascular treatment with renal vein stenting. A review of existing literature on endovascular management of nutcracker syndrome follows. METHODS: Three women (age range 28-43 years) presented with symptoms and imaging studies consistent with nutcracker syndrome. Symptoms included pelvic and flank pain in all 3 patients, and episodes of hematuria in 2 patients. Imaging studies demonstrated compression of the LRV between the superior mesenteric artery and aorta in 2 of the patients. The third patient was noted to have a circumaortic LRV. RESULTS: All 3 patients underwent venography and LRV stenting. Stents included a 12 × 40 mm self-expanding nitinol stent, 14 × 60 mm WALLSTENT, and 16 × 40 mm WALLSTENT. All patients were placed on clopidogrel postoperatively. The duration of follow-up ranged from 6 to 27 months. At follow-up, all 3 patients reported significant symptomatic improvement, and duplex ultrasonography demonstrated stent patency in all. CONCLUSIONS: Nutcracker syndrome is a rare condition that can be successfully treated with renal vein stenting via an endovascular approach. Results are encouraging at follow-up periods beyond 2 years.

Gross hematuria caused by nutcracker syndrome and segmental pseudoaneursym.

Nutcracker syndrome is a rare disorder characterized by extrinsic compression of left renal vein by the superior mesenteric artery and aorta. Prevalence of the disease is unknown, but presents most commonly with gross hematuria and flank pain. Diagnosis requires a high index of suspicion and treatment consists of a wide range of vascular surgical options with a more recent focus using an endovascular approach. We present a case of a 29-year-old female with continuous gross hematuria and flank pain from a segmental artery pseudoaneursym secondary to nutcracker and pelvic congestion syndrome.

Outcomes of conservative management in patients with nutcracker syndrome.

OBJECTIVE: This study aims to evaluate outcomes in nutcracker syndrome patients with tolerable symptoms and treated conservatively without invasive interventions. METHODS: This prospective study included patients treated conservatively. Promoting weight gain, the endpoint of the study was spontaneous resolution of symptoms. RESULTS: Sixteen patients (75% female and mean age 24.4 ± 3.5 years) underwent conservative management. Over a mean follow-up of 27.3 months [13-42, interquartile range (IQR)], the diameter ratio (5.5 [5-6.5, IQR] vs 4.3 [4.1-6], p = NS), the peak velocity ratio (6 [5-7, IQR] vs 4.8 [4.8-5.8], p = NS), beak angle (27° [24-30, IQR] vs 29° [24-32]; p = NS), and aortomesenteric angle (26° [23-29, IQR] vs 28° [24-30]; p = NS) exhibited no statistically significant changes. Complete resolution and improvement of symptoms were 28.5% and 31.4%, respectively, while 68.5% remained unchanged. CONCLUSIONS: This study shows that a conservative approach contributes to the spontaneous improvement or complete resolution in young adult patients with mild symptoms.

[Nutcracker syndrome treated by endovascular stenting of the left renal vein].

We describe endovascular stenting of the left renal vein to treat Nutcracker syndrome accompanied by gross hematuria. A 26-year-old woman with a history of hematuria and left flank pain was admitted to another hospital in January 2009. She was referred to our hospital in August 2010 for further investigation and treatment for suspected Nutcracker syndrome based on her medical history and the recurrent gross hematuria. Computed tomography (CT) imaging revealed compression of the left renal vein between the aorta and the superior mesenteric artery and cystoscopy revealed bloody urine from the left ureteric orifice. Ureteroscopy revealed diffuse bleeding from the renal pelvic mucosa. The cytodiagnosis of urine was Class II. She developed left flank pain and further recurrent hematuria in July 2011 and sought active treatment by stenting at our hospital. After we obtained the approval of the Ethical Review Board in our institution, we treated by endovascular stenting of the left renal vein. The venous phase of selective renal angiography during the procedure revealed dilation of the mid-renal vein with delayed flow into the inferior vena cava and tortuous dilated collateral vessels. Two ELUMINEXX Vascular Stents (12 x 40 mm) were deployed at the stenotic site of the left renal vein via the right femoral vein. This strategy improved the stenosis and collateral vessels. No significant postoperative adverse events developed other than dull back pain that disappeared after a few days, and the patient was discharged on postoperative day 4. CT findings three months after the procedure confirmed resolution of the left renal vein compression. Six months post-procedure, the patient had no left flank pain or further hematuria.

Endovascular management of nutcracker syndrome after migration of a laparoscopically placed extravascular stent.

Nutcracker syndrome results from compression of the left renal vein between the superior mesenteric artery and the aorta, leading to symptoms of hematuria and left flank pain. Management options include endovascular or laparoscopic extravascular stent placement, which is very appealing given the minimally invasive nature of these procedures. We report a case of migration of a laparoscopically placed extravascular stent for nutcracker syndrome that was treated successfully by endovascular stent placement.

A systematic review on nutcracker syndrome and proposed diagnostic algorithm.

OBJECTIVE: Nutcracker syndrome (NCS) is an increasingly recognized venous compressive disease. Although people with NCS can experience debilitating symptoms, making an accurate diagnosis can often be challenging owing to the broad spectrum of clinical presentations and radiologic findings. In the present systematic review, we assessed the most frequent clinical and radiologic criteria used in establishing a diagnosis of NCS and have proposed a comprehensive framework for clinical decision-making. METHODS: We performed a systematic review to identify all observational studies or case series conducted within the previous 10 years that had studied patients with a clinical and radiologic diagnosis of NCS. The extracted data included details related to the study design, participant demographics, presenting clinical features, and radiologic criteria. These details were compared between studies and synthesized to establish a comprehensive diagnostic framework that would be applicable to clinical practice. RESULTS: In the present review, we included 14 studies with a total of 384 patients with NCS. The most common clinical features of NCS were hematuria (69.5%), left flank or abdominal pain (48.4%), pelvic pain (23.1%), and varicocele (15.8%). Computed tomography and ultrasound were the most commonly used imaging modalities, with a threshold for left renal vein stenosis of >80% the most frequently used diagnostic parameter. Eight studies had used venography, with the renocaval pressure gradient the most commonly measured parameter. Two studies had reported using intravascular ultrasound. The findings from our review have shown that a thorough clinical workup of NCS should include critical evaluation of the presenting clinical features and exclusion of alternative diagnoses. All patients should undergo duplex ultrasound with or without the addition of computed tomography or magnetic resonance imaging. Any patient considered for therapeutic intervention should also undergo diagnostic venography with measurement of the renocaval pressure gradient and, if available, intravascular ultrasound with measurement of the left renal vein diameters. CONCLUSIONS: NCS is a challenging condition in terms of the diagnosis and management both. We have proposed a comprehensive diagnostic framework based on the currently available literature to aid in clinical decision-making.

The Journey and Barriers to Treatment of Patients With Renal Nutcracker Syndrome.

OBJECTIVE: To better understand renal nutcracker syndrome (NCS) from a patients' perspective starting at presentation and followed through to diagnosis and management METHODS: This descriptive study was conducted on a national level via a self-selected online survey distributed via river sampling by a post on the Facebook Page 'Renal Nutcracker Syndrome Support Group.' RESULTS: Of the 22 responses collected, 95.5% were female and 91% self-identified as White. 43% experienced symptoms as teenagers and 62% were diagnosed as young adults. Prior to receiving a definitive diagnosis, over half of the respondents were worked up for kidney stones (57%) and ovarian cysts (48%) and saw at least 10-15 providers. Nearly 80% experienced constant pain throughout the day. Pain management included prescription oral pain relievers (38%), prescription patches (29%), and physical therapy (19%). Surgical procedures included nephrectomy with auto transplant (38%), left renal vein transposition (10%), and laparoscopic extravascular stent placement (10%). Respondents had high healthcare utilization for management of NCS. Nearly 30% were unable to work and had filed for disability. CONCLUSION: Awareness of NCS should increase among healthcare providers of all specialties to improve quality of care to those living with NCS. It is crucial to keep NCS within the differential diagnosis in patients presenting with gross hematuria and unusual abdominal and/or flank pain.

Role of physical exercise in an overlooked nutcracker syndrome occurred in a patient with diaphragmatic relaxation: a case report.

Background: Nutcracker syndrome (NCS) is caused by extrinsic compression of the left renal vein (LRV), usually between the abdominal aorta (AA) and superior mesenteric artery (SMA). This rare disease includes symptoms such as hematuria, left flank pain or abdominal pain, varicocele in males, proteinuria, anemia, gynecological symptoms (dyspareunia, dysmenorrhea). Case report: We report the case of a 48-year-old female patient, who experienced left abdominal colic after intensive physical exercise, finally resulting in a diagnosis of NCS. This abdominal pain was disabling for daily activities, it was controlled by analgesic drugs and led to hospital admissions. In-depth examinations were recommended to the patient to investigate the etiology of these attacks. A bad rotated and ectopic left kidney, which was located superior to the spleen, at the level of the left hemithorax base, was found due to the presence of a diaphragmatic relaxation in the posterior area, which caused an upward displacement of the kidney, part of the colon and omental fat. Because of the presence of a compression of the LRV by the SMA and the AA, the nephrologist diagnosed a NCS, presenting with abdominal pain following physical exercise, proteinuria and dysmenorrhea. Conservative treatment was chosen for the patient. Conclusions: The patient was recommended to engage in a moderate and regular physical activity, avoiding acute and intense exercise: hypopressive abdominal gymnastics was suggested. The role of physical exercise in triggering painful attacks and its role in rehabilitation to prevent the same attacks was crucial for the patient.

The nutcracker syndrome.

Left renal vein (LRV) compression, commonly referred to as the nutcracker syndrome or renal vein entrapment syndrome, is a rare and often overlooked condition. Anatomically, the LRV traverses the space between the superior mesenteric artery and the aorta in close proximity to the origin of the artery. In affected individuals, the LRV is subjected to compression between these two structures, resulting in renal venous hypertension. A review of published data on this condition reveals either case reports or small case series. The classic symptoms of nutcracker syndrome include left flank pain with gross or microscopic hematuria. Patients are often children or young adults, with a slight predisposition for women who may also present with pelvic congestion symptoms such as pelvic pain and dyspareunia. Most patients have disease symptoms for many years and nondiagnostic investigations before proper diagnosis can be made. Appropriate diagnostic work-up and treatment may help alleviate patient morbidity from this chronic condition. Although surgical repair has been the standard of care, more recently endovascular intervention has become the first line of therapy. This tabular review compiles published cases in the adult population during the period between 1980 and 2009.

Nutcracker syndrome in a patient with a history of inferior vena cava ligation.

We report the case of a child with clinical and radiological signs of nutcracker syndrome who had a history of inferior vena cava ligation during a previous surgery. He was referred for evaluation of abdominal pain and hematuria. Entrapment of the left renal vein between the superior mesenteric artery and the aorta with aneurysmal dilatation was detected on Doppler ultrasonography. Magnetic resonance angiography revealed paravertebral and epidural collateral vessels.

Nutcracker Syndrome: How to Diagnose It and When/How Should It Be Treated in the Pelvic Venous Disease Population.

With wider recognition of left renal vein compression / obstruction, especially as an incidental finding, the significance as it relates to the patient's symptoms needs to be evaluated in light of variable practices and results of treatment. This communication deals with problems of diagnosis, clinical significance, options and indications for treatment.

Nutcracker Syndrome-A Rare but Important Cause of Varicocele in Adolescent Boys.

Nutcracker syndrome is a complex of clinical symptoms due to compression of the left renal vein between abdominal aorta and superior mesenteric artery. Hematuria and pelvic or back pain are the most common presenting symptoms with varicocele being an uncommon clinical finding in these patients especially in children. Doppler ultrasound, computed tomography and selective left renal vein phlebography are useful to confirm the diagnosis. Treatment can be conservative or surgical depending on the severity of symptoms. Here, we report a 13-year-old boy with left flank pain and varicocele on examination who on evaluation was found to have nutcracker syndrome as the etiology.

Combined Superior Mesenteric Artery Syndrome and Nutcracker Syndrome in a Young Patient: A Case Report and Review of the Literature.

BACKGROUND Superior mesenteric artery syndrome is the compression of the third portion of the duodenum between the superior mesenteric artery and the aorta causing abdominal pain and vomiting. Nutcracker syndrome is the compression of the left renal vein between the superior mesenteric artery and the aorta causing symptoms related to renal congestion. Both entities, although well described in the literature, are individually rare, and even though they might share a common etiology, their co-existence has been reported in only a few case reports. CASE REPORT An 18-year-old male, previously healthy, presented with postprandial abdominal pain relieved by bilious vomiting that started shortly after he lost weight fasting. Our investigation revealed superior mesenteric artery syndrome as well as a compressed left renal vein. He was started on an enriched fluid diet which was progressed gradually as he regained weight. His left renal vein compression at the time was asymptomatic; it will be followed up for possible resolution after the patient's weight returns to normal. CONCLUSIONS Superior mesenteric artery syndrome is to be suspected in patients with abdominal pain following weight loss. Conservative treatment with a focus on weight regain will cure most cases. Asymptomatic or mildly symptomatic nutcracker syndrome is treated conservatively. For patients requiring intervention, laparoscopic extravascular titanium stent placement seems to be the least invasive promising option today, awaiting further definitive studies.

Two Peculiarities of the Nutcracker Syndrome: Rare Association with Multiples Thrombosis and Successful Medical Treatment (Pentoxifylline).

The nutcracker syndrome (NCS) is a rare condition characterized by the entrapment of the left renal vein between the superior mesenteric artery and the aorta. Clinically, it presents with hematuria, flank pain, and symptoms of pelvic venous congestion. It is more frequent in females. Conservative treatment is usually proposed children but in adults, NCS has to be treated by surgical or endovascular methods. Drug therapy is not proposed for the treatment of NCS. We report a case of a young patient who presented with recurrent gross hematuria. Our patient was treated with pentoxifylline three times daily and anti-coagulation, with a favorable outcome.

Salvage Renal Autotransplant Following Previous Renal Vein Stenting in Nutcracker Syndrome.

OBJECTIVES: Nutcracker syndrome is rare, and a proportion of patients with this syndrome continue to have intractable pain and symptoms. Due to the heterogeneity of patients' chief complaints and symptoms, the surgeon's preferred approach may be inherently different but is of paramount importance to the outcome. MATERIALS AND METHODS: We present 4 cases in which renal autotransplant with extraction and ligation of previously placed gonadal coils was performed following previously attempted renal vein stenting or combined renal vein transposition followed by renal vein stenting. RESULTS: Autotransplant resulted in flank pain resolution with improvement in symptoms associated with pelvic congestion syndrome. CONCLUSIONS: The approach to such cases requires meticulous and adequate vena cava exposure, with preparation for potential caval reconstruction. No firm inferences can be made from such a small series; however, we believe in renal autotransplant as first-line therapy, and failure after an initial renal vein stent should be salvaged by renal autotransplant over further endovascular attempts.

RENAL VEIN THROMBOSIS DUE TO POSTERIOR NUTCRACKER SYNDROME.

Thrombosis of the left renal vein (LRV) is a rare occurrence usually associated with hypercoagulable disorders. It may also be caused by extrinsic compression due to anatomical variations. Such variations, known as nutcracker phenomenon (NP), are usually completely asymptomatic, and they have been described in three variants: a narrowed aortomesenteric angle (AMA) with entrapment of the LRV; a second, rarer variant with an anomalous retro aortic LRV compressed between the abdominal aorta (AA) and the spine (posterior nutcracker syndrome, PNCS); and a third variant with a duplicated LRV with a pre- and retroaortic course, compressed both anteriorly and posteriorly. The development of symptoms secondary to NP is mainly due to renal congestion, often difficult to identify, and includes flank pain, ipsilateral varicocele, hematuria, and orthostatic proteinuria, among others. The most severe complication of NCS is LRV thrombosis with or without associated predisposing prothrombotic factors. The present case associates a PNCS to LRV thrombosis with a floating thrombus in the inferior vena cava and pulmonary embolism.