Síndrome de cascanueces y agenesia renal derecha. Una rara asociación / Nutcracker Syndrome and Right Renal Agenesis. A Rare Association

Introducción: El síndrome de cascanueces se considera una anomalía infrecuente y poco pensada en la práctica médica; su incidencia no está bien establecida debido a su sintomatología variada. La agenesia renal unilateral se estima entre 1/2500 y 1/4000 nacidos vivos. Objetivos: Describir una paciente de 18 años con sospecha prenatal de agenesia renal derecha confirmada por imágenes después del nacimiento, que ingresó por proteinuria. Presentación del caso: Paciente de 18 años con agenesia renal derecha conocida, en la que un examen de orina detectó proteinuria desde los 13 años. En su estudio se clasificó como proteinuria ortostática y evolutivamente refirió dolor lumbar izquierdo ligero y transitorio. En el ultrasonido renal, realizado para valorar crecimiento del riñón único, se detectó dilatación de la vena renal izquierda. Se repitió el estudio ecográfico para precisar ángulo aorto-mesentérico y dilatación de vena renal izquierda, y se confirmó el síndrome de cascanueces. Conclusiones: La asociación entre agenesia renal derecha y síndrome de cascanueces, resulta extremadamente rara, y, cuando se presenta con proteinuria ortostática y dolor lumbar ocasional, debe seguirse en forma expectante, pero no se necesita tratamiento quirúrgico en la mayoría de los casos(AU)

Introduction: Nutcracker syndrome is considered an infrequent and poorly thought out anomaly in medical practice; its incidence is not well established due to its varied symptomatology. Unilateral renal agenesis is estimated to be between 1/2500 and 1/4000 live births. Objectives: To describe an 18-year-old female patient with suspected pre-natal imaging-confirmed right renal agenesis after birth, who was admitted due to proteinuria. Case presentation: An 18-year-old female patient with known right renal agenesis, in whom a urine test detected proteinuria from the age of 13. In the study it was classified as orthostatic proteinuria and evolutionarily she referred mild and transient left low back pain. Renal ultrasound, performed to assess single kidney growth, showed dilation of the left renal vein. The ultrasound study was repeated to specify aorto-mesenteric angle and left renal vein dilation, and nutcracker syndrome was confirmed. Conclusions: The association between right renal agenesis and nutcracker syndrome is extremely rare, and, when it presents with orthostatic proteinuria and occasional low back pain, it should be followed expectantly, but surgical treatment is not needed in most cases(AU)

A Case of Orthostatic Proteinuria Progressed to Persistent Proteinuria Associated with Renal Pathology

Orthostatic or postural proteinuria is the most common cause of asymptomatic proteinuria in children. As orthostatic proteinuria (OP) is a benign disease with relatively good prognosis, it has no specific management, and patients only need to be observed. However, if OP shows a persistently high level of proteinuria, in theory, glomerular changes can occur. An 11-year-old girl was referred to the hospital due to asymptomatic proteinuria and was diagnosed as having OP based on the results of clinical and laboratory examinations, urinalysis, and protein/creatinine (TP/Cr) ratio at both supine and erect positions. During follow-up observation, the 24-hour TP/Cr ratio was persistently higher than 1.5 mg/mg for 2 years. We performed renal biopsy, which showed mesangial proliferative glomerular lesions with focal effacement of the podocyte foot processes, but without immune depositions. OP can be accompanied by glomerular lesions if moderate to severe proteinuria persists.

A Case of Orthostatic Proteinuria Progressed to Persistent Proteinuria Associated with Renal Pathology

Orthostatic or postural proteinuria is the most common cause of asymptomatic proteinuria in children. As orthostatic proteinuria (OP) is a benign disease with relatively good prognosis, it has no specific management, and patients only need to be observed. However, if OP shows a persistently high level of proteinuria, in theory, glomerular changes can occur. An 11-year-old girl was referred to the hospital due to asymptomatic proteinuria and was diagnosed as having OP based on the results of clinical and laboratory examinations, urinalysis, and protein/creatinine (TP/Cr) ratio at both supine and erect positions. During follow-up observation, the 24-hour TP/Cr ratio was persistently higher than 1.5 mg/mg for 2 years. We performed renal biopsy, which showed mesangial proliferative glomerular lesions with focal effacement of the podocyte foot processes, but without immune depositions. OP can be accompanied by glomerular lesions if moderate to severe proteinuria persists.

A propósito de dos casos de síndrome de cascanueces / A propos of two nutcracker syndrome cases

Se presentan 2 pacientes con síndrome de cascanueces de sexo masculino de 7 y 12 años. El primero asiste a consulta por hematuria y dolor en el flanco izquierdo; y el segundo, por crisis de dolor intenso recurrente en flanco izquierdo y proteinuria ortostática. En ambos pacientes el estudio ultrasonográfico renal permitió sospechar la entidad por la dilatación de la vena renal izquierda, y la emergencia anómala de la arteria mesentérica superior. En ambos casos la tomografía (angiotac) demostró la anomalía vascular y permitió seguir un tratamiento sintomático expectante. Los 2 pacientes se consultaron por los síntomas más frecuentes del síndrome: dolor en el flanco en ambos, hematuria macroscópica en uno, y proteinuria ortostática en el otro; ambos presentaban las alteraciones de un cascanueces anterior. El ultrasonido renal buscando la dilatación de la vena renal izquierda y el trayecto de la arteria mesentérica, permite establecer el diagnóstico que se confirma con otros estudios de imágenes.

Two male patients, who presented with nutcracker syndrome, were reported in this article. A seven years-old patient went to the doctor´s on account of hematuria and pain in his left flank whereas a 12 years-old patient suffered recurrent intense pain in his left flank and orthostatic proteinuria. The renal ultrasonography performed in both patients showed dilated left renal vein and anomaly of the upper mesenteric artery, all of which allowed suspecting of this disease. The tomography (angiotac) proved the vascular anomaly and allowed indicating an expecting symptomatic treatment. These two patients were seen at the medical service because both presented with the most frequent symptoms of the syndrome, that is, pain at flanks, macroscopic hematuria in one and orthostatic proteinuria in the other. Both of them also showed alterations from a previous nutcracker event. The renal ultrasound to look for dilation of the left renal vein and the path of the mesenteric artery allows making the final diagnosis that is further confirmed with other imaging studies.

Fenómeno y síndrome de cascanueces asociado a hematuria y proteinuria ortostática / Nutcracker phenomenon and syndrome associated to hematuria and orthostatic proteinuria

El fenómeno cascanueces es una compresión de la vena renal izquierda, lo más frecuente es el ángulo formado por la arteria aorta y la mesentérica superior, por una emergencia anormal de la mesentérica. Cuando aparecen síntomas derivados de esta anomalía se le denomina síndrome de cascanueces. Este síndrome puede producir síntomas y signos muy variados, pero entre ellos, la hematuria, la proteinuria ortostática, el varicocele, la congestión pélvica crónica, el dolor abdominal y en flanco, y la intolerancia ortostática son los más frecuentes. La hematuria y la proteinuria ortostática son 2 manifestaciones que frecuentemente tienen que enfrentar el médico general integral y el pediatra, y es necesario tener en cuenta al síndrome de cascanueces en el diagnóstico diferencial de estas alteraciones. La hematuria es muy frecuente y la proteinuria ortostática tiene como causa principal el síndrome cascanueces. Por tal motivo consideramos importante esta breve revisión del tema, para poder enfrentar estas situaciones teniendo en cuenta todas sus posibilidades diagnósticas

Nutcracker phenomenon is left renal vein compression, more frequently in the angle formed by the aorta artery and the superior mesenteric artery due to abnormal emergency of the mesentery. When symptoms derived from this anomaly occur, this situation is called nutcracker syndrome. It may cause very varied symptoms and signs such as hematuria, orthostatic proteinuria, varicocele, chronic pelvic congestion, abdominal pain and flank pain, and orthostatic intolerance as the most common ones. Hematuria and orthostatic proteinuria are two frequent manifestations that the family physician and the pediatrician must face, so it is necessary to take the nutcracker syndrome into account for the differential diagnosis of these alterations. Hematuria is more frequent and orthostatic proteinuria is mainly caused by the nutcracker syndrome. Therefore, we consider that this brief review on this topic is important to cope with these situations and to bear in mind all their diagnostic possibilities

Mesangial Hypercellularity in a Patient with Nutcracker Syndrome and Orthostatic Proteinuria

Orthostatic or postural proteinuria is a benign condition characterized by the presence of protein in urine samples collected in the upright position during the day and its absence in the supine position. Recently, nutcracker phenomenon has been documented as the source of postural proteinuria. The nutcracker phenomenon refers to compression of the left renal vein between the aorta and superior mesenteric artery, resulting in elevation of pressure in the left renal vein, leading to congestion of the left kidney and occasionally to collateral veins formation. Entrapment of the left renal vein is a cause of left-sided gross hematuria, ureteral and peripelvic varices, unexplained left flank pain and variable degrees of orthostatic proteinuria. We report the case of a 14-year-old girl with orthostatic proteinuria, diagnosed as having nutcracker syndrome by doppler sonography and MR angiography. Because daily protein excretion was more than 1.5 grams over 3 years of follow up, we decided to perform a renal biopsy which revealed moderate mesangial cell proliferation in all glomeruli.

A Case of Nutcracker Syndrome Presenting with Orthostatic Proteinuria

Orthostatic proteinuria is documented as a benign condition and the most common cause of isolated proteinuria. The etiology and pathogenesis of orthostatic proteinuria is not clear yet. Recently there were a few report that nutcracker syndrome seemed to cause orthostatic proteinuria. We experienced a case of a twelve-year-old female patient with incidently discovered orthostatic proteinuria who was suspected to have nutcracker phenomenon by doppler sonography. We confirmed this patient as nutcracker syndrome by renal venography.

Lipoprotein(a) Level and Influential Factors in Children with Common Renal Diseases

PURPOSE: Lipoprotein(a) is a genetically determined risk factor for atherosclerotic vascular disease and is elevated in patients with renal disease. Especially the patients with nephrotic syndrome exhibit excessively high Lp(a) plasma concentrations. Also the patients with end- stage renal disease have elevated Lp(a) levels. But the mechanism underlying this elevation is unclear. Thus, in this study, by measuring the level of serum Lp(a) in common renal diseases in children, we hoped to see whether there would be a change in Lp(a) in renal diseases other than nephrotic syndrome. Then, we figured out its implications, and looked for the factors that affect the Lp(a) concentrations. METHODS: A total of 75 patients(34 patients with hematuria of unknown etiology, 10 with hematuria and hypercalciuria, 8 with IgA nephropathy, 8 with poststreptococcal glomerulonephritis, 3 with Henoch-Schonlein nephritis, 7 with urinary tract infection, and 5 with orthostatic proteinuria) were studied. The control group included 20 patients without renal and liver disease. Serum Lp(a), total protein, and albumin levels, 24-hour urine protein and calcium excretions, creatinine clearance and the number of RBCs and WBCs in the urinary sediment were evaluated. Data analysis was performed using the Student t-test and a P-value less than 0.05 was considered to be statistically significant. RESULTS: Lp(a) was not correlated with 24-hour urine calcium and creatinine. Lp(a) level had a positive correlation with proteinuria and negative correlation with serum albumin and serum protein. Among the common renal diseases in children, Lp(a) was elevated only in orthostatic proteinuria(P<0.05). CONCLUSION: Lp(a) is correlated with proteinuria, serum protein, and serum albumin, but not with any kind of specific renal disease. Afterward, Lp(a) needs to be assessed in patients with orthostatic proteinuria and its possible role as a prognostic factor could be confirmed.

Lipoprotein(a) Level and Influential Factors in Children with Common Renal Diseases

PURPOSE: Lipoprotein(a) is a genetically determined risk factor for atherosclerotic vascular disease and is elevated in patients with renal disease. Especially the patients with nephrotic syndrome exhibit excessively high Lp(a) plasma concentrations. Also the patients with end- stage renal disease have elevated Lp(a) levels. But the mechanism underlying this elevation is unclear. Thus, in this study, by measuring the level of serum Lp(a) in common renal diseases in children, we hoped to see whether there would be a change in Lp(a) in renal diseases other than nephrotic syndrome. Then, we figured out its implications, and looked for the factors that affect the Lp(a) concentrations. METHODS: A total of 75 patients(34 patients with hematuria of unknown etiology, 10 with hematuria and hypercalciuria, 8 with IgA nephropathy, 8 with poststreptococcal glomerulonephritis, 3 with Henoch-Schonlein nephritis, 7 with urinary tract infection, and 5 with orthostatic proteinuria) were studied. The control group included 20 patients without renal and liver disease. Serum Lp(a), total protein, and albumin levels, 24-hour urine protein and calcium excretions, creatinine clearance and the number of RBCs and WBCs in the urinary sediment were evaluated. Data analysis was performed using the Student t-test and a P-value less than 0.05 was considered to be statistically significant. RESULTS: Lp(a) was not correlated with 24-hour urine calcium and creatinine. Lp(a) level had a positive correlation with proteinuria and negative correlation with serum albumin and serum protein. Among the common renal diseases in children, Lp(a) was elevated only in orthostatic proteinuria(P<0.05). CONCLUSION: Lp(a) is correlated with proteinuria, serum protein, and serum albumin, but not with any kind of specific renal disease. Afterward, Lp(a) needs to be assessed in patients with orthostatic proteinuria and its possible role as a prognostic factor could be confirmed.

A Case of Nutcracker Syndrome Associated with Orthostatic Proteinuria and Idiopathic Chronic Fatigue in a Child

The nutcracker syndrome is the congestion of left renal vein due to the compression of left renal vein by the aorta and the superior mesenteric artery and has been known as the cause of hematuria with or without left renal flank pain, mild to moderate proteinuria and orthostatic proteinuria. We present here one case of 13.5 year of girl has severe typical nutcracker syndrome with orthostatic protinuria and idiopathic chronic fatigue.