Enteric bacteria and ingested inert particles translocate to intraperitoneal prosthetic materials

Abstract

Sterile and endotoxin-free biomaterials commonly used in prosthetic devices (Dacron velour, woven Dacron, and Biomer polyurethane) and cotton (control material) were implanted intraperitoneally in mice with normal enteric flora. Intraperitoneal Biomer and woven Dacron became contaminated with 100 to 10,000 enteric bacteria, including Escherichia coli, Pseudomonas aeruginosa, enterococci, and staphylococci species, within 3 days; intraperitoneal cotton and Dacron velour were contaminated within 24 hours. Mesenteric lymph nodes showed parallel incidences of translocation. The peritoneal cavity became contaminated only if the biomaterial itself became contaminated. No bacterial overgrowth, perforation, or histologic changes in the bowel were found. Subcutaneous biomaterials remained sterile. Ingested fluorescent beads appeared in enterocytes, in lamina propria within macrophages, and in intraperitoneal biomaterials. The data suggest that intraperitoneal sterile reactive stimuli can induce bacterial translocation to the dense prosthesis directly through the intact normal bowel wall. One of the mechanisms seems to involve phagocytosis of particles and bacteria within the bowel wall that are then chemotactically attracted to nearby sites of inflammation.