Papers Pending Publication

Sufferers of Abdominal Vascular Compressions Syndromes (AVCS), including Renal Nutcracker Syndrome, present with a wide range of symptoms, not all of which are currently understood. Surgical outcomes vary and sometimes multiple compressions are present. Past research has shown that occlusion of the renal vein can increase venous pressure, thus increasing interstitial pressure, which initiates a transfer of fluid to the lymphatic system. If this pressure increase is chronic, the abdominal lymphatic system must assume the extra burden of this fluid transfer. The compression of any vein also implies an effect on the blood flow velocity and sometimes direction. This can cause blood endothelial cells to release mediators that can activate mast cells situated close to the vein wall. The mast cells then degranulate and release other mediators, causing an in-flammatory cascade. The implications of this process are numerous, including damage to the vein itself (vein walls and endothelial cells), release of pro-inflammatory markers, damage to the ex-tra-cellular matrix, angiogenesis and neolymphangiogenesis, and increased volume transfer to the lymphatic system. The increased burden on the lymphatic system has wide-ranging implications, given that the abdominal lymphatics are highly inter-connected within the pelvis, abdomen and thorax, and that mast cell mediators spread throughout the body to affect it systemically. The au-thor proposes that these factors could explain the wide-ranging pain and the interplay of symp-toms seen in AVCS patients.