Meningitis postquirúrgica. Características diferenciales de la meningitis aséptica post-quirúrgica

Abstract

Postsurgical meningitis is a rare complication that is accompanied by an increase of hospital stay and high mortality. Some of these cases are not due to a true infection but due to an aseptic inflammation of the meninges denominated aseptic postsurgical meningitis (APSM). Proper identification of these cases would allow better use of antimicrobial drugs. A retrospective study of patients with postsurgical meningitis in a universitary hospital for 14 years. We describe the clinical characteristics of patients with postsurgical bacterial meningitis (PBM) compared to those of patients with APSM. During the studied period 35 patients (71%) with PBM and 14 patients (29%) with (APSM) were identified. The mean age of patients with PBM was similar to that of patients with APSM. There was a male predominance in the group of PBM (71%) compared with patients with APSM (36%, p = 0.020). Patients with intracranial hemorrhage tended to present more cases of APSM (64%) than of PBM (34%, p = 0.055). Patients undergoing posterior fossa craniotomy (p = 0.092) and those receiving steroids (p = 0.051) showed a greater tendency to suffer APSM. It was also noted a trend towards present PBM in patients who had suffered an infection in the previous month (p = 0.072). There were seven patients with PBM (20%) with a cell count above 5000 cells/mm3 in CSF, values not found in any patients with APSM. No differences were detected in the glycorrachia and proteinorrachia between the two groups. The most common bacteria isolated were coagulase negative Staphylococcus and S. aureus. In 5 patients (14%) non fermenting gram-negative bacillus (Pseudomonas aeruginosa and Acinetobacter spp) were isolated. There were no deaths attributed to any type of postsurgical meningitis. Patients admitted for brain haemorrhage, undergoing posterior fossa surgery or receiving steroids tend to develop APSM. A CSF cell count above 5000 cells / mm3 strongly suggests MBP.