Pancreatic pseudocyst is defined as single/multiple fluid collection with high amylase content, surrounded by fibrous or granulation tissue within the lesser sac.
It usually occurs around 4 weeks after an acute attack of pancreatitis, where patient complains of epigastric fullness, pain, nausea and vomiting.
If it's infected, there may be fever, rigors and sweating.
However, pseudocyst can be also caused by chronic pancreatitis or any pancreatic trauma.
Firm, tender epigastric mass is felt, with indistinct lower edge, and inability to get above the swelling.
It moves slightly with respiration.
Percussion reveals resonant note since the pseudocyst is covered by stomach.
However, it's not possible to demonstrate fluctuation and fluid thrill.
Pancreatic pseudocyst must be differentiated from acute fluid collection and pancreatic abscess.
Usually just based on the clinical scenario and USG abdomen (or sometimes CT), one will be able to distinguish these conditions.
However, one must not forget that a cystic neoplasm may mimic as a chronic pseudocyst.
To differentiate, one needs to perform aspiration of the swelling under EUS guidance (EUS = endoscopic ultrasound).
Then, sent the aspirate for amylase level, cytology and CEA level.
Typically, if it's a chronic pseudocyst - high amylase level, with leucocytes and CEA < 400 ng/ml.
However, in case of mucinous neoplasm - CEA > 400 ng/ml.
Treatment consist of drainage of the pseudocyst.
There are 3 approaches towards the drainage :
1) Percutaneous transgastric cystogastrostomy under imaging guidance, then by placing a double pigtail catheter, one end within the cystic cavity, another within the gastric lumen for drainage.
Chance of recurrence : not more than 15 %
2) Endoscopic method under EUS guidance : By puncturing the wall of stomach/duodenum to gain access into the pseudocyst cavity, then insertion of a drainage tube one end within the cystic cavity, another within the gastric lumen for drainage.
3) Surgical method by internal drainage into gastric/jejunal lumen. Rate of recurrence is not more than 5%.