In some cases, emergency surgery is necessary upon presentation. A six-week trial of medical treatment is recommended in pediatric cases. The goal of medical treatment for SMA syndrome is resolution of underlying conditions and weight gain. Medical treatment may involve nasogastric tube placement for duodenal and gastric decompression, mobilization into the prone or left lateral decubitus position, the reversal or removal of the precipitating factor with proper nutrition and replacement of fluid and electrolytes, either by surgically inserted jejunal feeding tube, nasogastric intubation, or peripherally inserted central catheter (PICC line) administering total parenteral nutrition (TPN). Pro-motility agents such as metoclopramide may also be beneficial. Symptoms may improve after restoration of weight, except when reversed peristalsis persists, or if regained fat refuses to accumulate within the mesenteric angle. Most patients seem to benefit from nutritional support with hyperalimentation irrespective of disease history.If medical treatment fails, or is not feasible due to severe illness, surgical intervention is required. The most common operation for SMA syndrome, duodenojejunostomy, was first proposed in 1907 by Bloodgood. Performed as either an  open surgery or laparoscopically, duodenojejunostomy involves the creation of an anastomosis between the duodenum and the jejunum, bypassing the compression caused by the AA and the SMA. Less common surgical treatments for SMA syndrome include Roux-en-Y duodenojejunostomy, gastrojejunostomy, anterior transposition of the third portion of the duodenum, intestinal derotation, division of the ligament of Treitz (Strongs operation), and transposition of the SMA.
Prospective studies have found a subgroup of PMR patients with hand edema, as well as other similarities. Thus, RS3PE has been proposed as a condition related to PMR or even that they are both part of the same disorder. However, PMR typically requires protracted courses of steroids, whereas corticosteroids can be tapered more quickly with persisting remission in RS3PE.Other rheumatological disorders that can cause the features typical for RS3PE include late onset (seronegative) rheumatoid arthritis, acute sarcoidosis, ankylosing spondylitis and other spondyloarthropathies such as psoriatic arthropathy, mixed connective tissue disease, chondrocalcinosis and arthropathy due to amyloidosis.RS3PE has been documented in patients with cancers (Non-Hodgkins lymphoma, gastric cancer, pancreatic cancer, lung cancer, breast cancer, colon cancer, prostate cancer and bladder cancer, among others), in whom it might represent a paraneoplastic manifestation. Other underlying disorders include vasculitides such as polyarteritis nodosa.Other causes of edema include heart failure, hypoalbuminemia, nephrotic syndrome and venous stasis. The key distinguishing feature is that these conditions dont tend to manifest with pitting edema at the back of the hands. Pathogenesis
The disease mechanism (pathophysiology) of RS3PE remains unknown. One study suggested a possible role for vascular endothelial growth factor. A study using magnetic resonance imaging found that tenosynovitis of the extensors of the hands and feet is the major contributor to edema. Diagnosis
Ultrasonography and magnetic resonance imaging of the hands and/or feet have been proposed as useful diagnostic investigations in RS3PE.Some studies linked RS3PE to HLA-B27 whereas others have not. Treatment
RS3PE responds excellently to low dose corticosteroids, with sustained and often complete remission.