Ruptured Splenic Artery Pseudoaneurysm Causing Hemorrhage Into a Pancreatic Pseudocyst.

ABSTRACT: This case report describes fatal exsanguination due to splenic artery hemorrhage into a pancreatic pseudocyst with cystogastrostomy in a 46-year-old woman. The decedent had a complicated medical history including necrotizing pancreatitis, giant pseudocyst formation after cystogastrostomy procedure, and coiling of a hemorrhagic splenic artery. While hospitalized, she underwent embolization of a ruptured splenic artery pseudoaneurysm. Weeks later, she went into hemorrhagic shock and was ultimately pronounced at the hospital. Doctors suspected an upper gastrointestinal (GI) bleed as the cause of death; however, the patient was too unstable to undergo interventional radiology at the time.At autopsy, the pancreas was hemorrhagic and included a 15 × 15 × 15-cm pseudocyst, which contained a metallic stent from a cystogastrostomy. This case describes a unique co-occurrence of numerous common complications of chronic pancreatitis. There are multiple ways by which pancreatitis can cause upper and lower GI bleeds. In this case, the presence of a cystogastrostomy stent allowed for a ruptured pseudoaneurysm to hemorrhage through the pancreatic pseudocyst and into the stomach and duodenum, mimicking the presentation of a more common upper GI bleed. The pseudocyst then ruptured causing abdominal hemorrhage. The passage of hemorrhage through a cystogastrostomy stent is not described in other literature.

Acinetobacter strains carry two functional oligosaccharyltransferases, one devoted exclusively to type IV pilin, and the other one dedicated to O-glycosylation of multiple proteins.

Multiple species within the Acinetobacter genus are nosocomial opportunistic pathogens of increasing relevance worldwide. Among the virulence factors utilized by these bacteria are the type IV pili and a protein O-glycosylation system. Glycosylation is mediated by O-oligosaccharyltransferases (O-OTases), enzymes that transfer the glycan from a lipid carrier to target proteins. O-oligosaccharyltransferases are difficult to identify due to similarities with the WaaL ligases that catalyze the last step in lipopolysaccharide synthesis. A bioinformatics analysis revealed the presence of two genes encoding putative O-OTases or WaaL ligases in most of the strains within the genus Acinetobacter. Employing A. nosocomialis M2 and A. baylyi ADP1 as model systems, we show that these genes encode two O-OTases, one devoted uniquely to type IV pilin, and the other one responsible for glycosylation of multiple proteins. With the exception of ADP1, the pilin-specific OTases in Acinetobacter resemble the TfpO/PilO O-OTase from Pseudomonas aeruginosa. In ADP1 instead, the two O-OTases are closely related to PglL, the general O-OTase first discovered in Neisseria. However, one of them is exclusively dedicated to the glycosylation of the pilin-like protein ComP. Our data reveal an intricate and remarkable evolutionary pathway for bacterial O-OTases and provide novel tools for glycoengineering.