Twenty-nine patients who incurred a transperitoneal low-velocity gunshot wound to their spine were evaluated for the occurrence of spinal infectious complications. All patients underwent an exploratory laparotomy to determine the extent of viscera involvement. No attempt was made to debride the involved spinal area, and the bullet was not removed unless it was easily accessible. Of the 21 patients with a parenchymal and/or noncolonic viscous injury, 17 (77%) were treated with intravenous (i.v.) antibiotics for a minimum of 5 days the remainder received treatment for a maximum of 48 h. All 8 patients with colonic injuries received a minimum of > or = 5 days of antibiotic treatment. Follow-up averaged 44.9 months (range 3-144 months). Only 1 (4.7%) patient with either a noncolonic or parenchymal perforation developed an infectious complication (subdiaphragmatic abscess); two patients (25%) with colonic perforations developed a psoas abscess. No patient developed a spinal infection. This study suggests that patients who sustain a transperitoneal low-velocity gunshot wound to their spine do not need to undergo spinal debridement and may be treated with parenteral antibiotics. Any course of broad-spectrum antibiotics for 5 days appears to minimize infectious complications. Bullet removal and missile tract debridement of the spine is not routinely necessary.