Nutcracker Syndrome – Vascular Implications in the Diagnosis of Lumbar Pain and Hematuria

Abstract

Background. The Nutcracker Syndrome (NCS) is a rare vascular disorder resulting from the compression of the Left Renal Vein (LRV), most frequently between the superior mesenteric artery and the abdominal aorta. Although epidemiological data are limited, NCS primarily affects females, typically manifesting in the second and third decades of life. Clinical features commonly include hematuria, orthostatic proteinuria, left-sided lumbosacral pain, renal dysfunction, varicocele in men, and pelvic symptoms with vulvar varicosities in women.

Aim. This systematic review aims to analyze the vascular implications of NCS in the diagnosis of lumbar pain and hematuria, and to summarize the key diagnostic methods for this syndrome.

Material and methods. 

The pathophysiological mechanism involves compression of the LRV, which leads to reduced blood flow in the LRV and consequently to a decreased Glomerular Filtration Rate (GFR). Diagnosis of NCS relies primarily on non-invasive imaging studies, such as Doppler Ultrasonography (Doppler US), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI), supplemented by invasive procedures like Intravascular Ultrasonography (IVUS) and venography when necessary.

Results. The anterior variant of NCS is significantly more common than the posterior type. Imaging findings demonstrating severe LRV stenosis are crucial for diagnosis.

Conclusions. The lack of universally accepted diagnostic criteria significantly complicates the diagnosis of NCS and necessitates their formal establishment. Defining clear criteria would greatly facilitate the recognition and subsequent treatment of this syndrome.