Anterior sacral meningocele presenting with purulent rectal discharge and altered mental status

A 30-year-old woman with a history of fever and purulent rectal discharge for 3 months was transferred to our department with altered sensorium for several weeks. CSF study was suggestive of pyogenic meningitis with growth of enterococci on incubation. CT brain showed pneumocephalus (figure 1A), and MRI of lumbosacral region showed anterior meningocele compressing on the posterior rectal wall. Pressure erosion of the posterior rectal wall possibly led to purulent rectal discharge. Cases of anterior sacral meningocele have been reported in literature presenting as bacterial meningitis1 and perianal abscess.2 Pneumocephalus and air-fluid level (figure 2A) in the meningocele sac in our case suggest possible infection with gas-producing microorganisms or communication with the gut, or both.