Effect of intraperitoneal administration of sterile human cerebrospinal fluid in rats.

Introduction: Distal ventriculoperitoneal shunt failure can be attributed to unabsorbed cerebrospinal fluid (CSF) from peritoneum. The objective of the experiment was to determine peritoneal reaction in rats after intraperitoneal administration of human CSF and evolution of local inflammatory response.

Materials And Methods: Wistar rats were used divided into four groups: three groups in which intraperitoneal injection of 3 mL, 2 mL and 0.5 mL of sterile human CSF was done and a control group. After sacrificing the animals, at 24, 48 or 72 hours, macro- and microscopic examination of the peritoneal cavity and peritoneal fluid analysis were performed. The experiment was done in compliance with legislation regarding animal research.

Results: Administration of high dose CSF (3 mL) led to death of all specimens. The dose of 0.5 mL of sterile CSF intraperitoneally administered was compatible with survival. Peritoneal response varied from necrotic-purulent reaction, with maximum intensity in group 1, and milder in group 2, to minimum inflammation in small foci and polymorphic cells in group 3. Inflammation only partially resolved in some specimens from group 3 after 72 hours, which incriminates the role of unabsorbed peritoneal CSF in pathogenesis of abdominal complications of ventriculoperitoneal shunts.

Conclusions: Intraperitoneal administration of sterile human CSF caused inflammatory response of varying degrees and with multiple locations. High doses of CSF led to death of specimens. At 24 hours, the peritoneal response ranging from congestion to purulent reaction was acute, intense and diffuse but after 72 hours, the inflammatory response was mild, focal and limited.