Tc-99m-PEG-liposomes target both adhesions and abscesses and their reduction by hyaluronate in rats with fecal peritonitis.
BACKGROUND
Abdominal adhesions and abscesses are a major source of morbidity and mortality after abdominal surgery and peritonitis. Adhesions are hard to detect with standard imaging techniques. Liposomes, coated with polyethylene glycol (PEG), represent an agent developed for infection imaging. This study investigated the capacity of 99mTc-PEG-liposomes to localize early adhesion formation after peritonitis. Additionally, the value of 99mTc-PEG-liposomes for therapy evaluation of hyaluronan solution, which reduces adhesion and abscess formation in experimental peritonitis, was assessed.


METHODS
In 24 rats, a bacterial peritonitis was induced by performing a cecal ligation and puncture procedure. The animals were treated with sodium chloride solution or 0.4% hyaluronan solution intra-abdominally. One week later, scintigraphy was performed using 99mTc-PEG-liposomes, and abnormal focal uptake in the abdomen was scored. Thereafter, autopsy was performed and adhesions and abscesses were scored.


RESULTS
A significant correlation was found between the total adhesion score and the scintigraphic score (P < 0.01, r = 0.65). Treatment with hyaluronan significantly reduced the total adhesion score (P = 0.01). The size of abscesses significantly correlated with the scintigraphic score (P < 0.01, r = 0.65). Treatment with hyaluronan reduced the size of abscesses (P < 0.05).


CONCLUSIONS
99mTc-PEG-liposomes are able to detect early adhesions and abscesses and may be used for therapy evaluation of agents that reduce adhesions and abscesses.
Sikkink
Cornelis J J M
CJ
Department of Surgery, Maasland Hospital, Sittard, The Netherlands.
Reijnen
Michel M P J
MM
Laverman
Peter
P
Oyen
Wim J G
WJ
van Goor
Harry
H
D018784:Abdominal Abscess / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism; D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D002432:Cecum / Q000293:injuries; D004195:Disease Models, Animal; D005243:Feces; D006820:Hyaluronic Acid / Q000494:pharmacology; D008081:Liposomes / Q000493:pharmacokinetics; D008297:Male; D010538:Peritonitis / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism; D011092:Polyethylene Glycols / Q000493:pharmacokinetics; D011877:Radionuclide Imaging; D051381:Rats; D017208:Rats, Wistar; D013667:Technetium / Q000493:pharmacokinetics; D000267:Tissue Adhesions / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism
D000276:Adjuvants, Immunologic; D008081:Liposomes; D011092:Polyethylene Glycols; D013667:Technetium; D006820:Hyaluronic Acid