Proprionibacterium acnes infections of cerebrospinal fluid shunts

Abstract

Ventricular cerebrospinal fluid shunt infections with Proprionibacterium acnes are generally low-grade, indolent infections. Typical presentations include gradual shunt malfunction, nausea, headache, malaise, and infrequently, fever. In all, 489 shunt procedures performed between January 1992 and December 1995, and in 15 of these cases P. acnes was subsequently cultured from reservoir taps or an intraoperative culture which was obtained when the existing shunt components were revised. Six of these, representing 14.6% of shunt infections, were considered to be true P. acnes shunt infections, as they were associated with either CSF leukocytosis or the identification of gram-positive rods by gram stain. The others were considered to be probable contaminants. Detailed analysis of all 15 of these cases revealed that no patient had positive CSF cultures after removal of the infected shunt and the initiation of antibiotics. Given the benign characteristics of P. acnes shunt infections, the broad sensitivity to antibiotics, and the rapid sterilization of the cerebrospinal fluid, it may be possible to treat such cases with short-term perioperative antibiotics and replacement of the shunt components, in place of prolonged external ventricular drainage and antibiotics. This would have eliminated 8 operative procedures and reduced the estimated length of stay by 77 patient-days in these 15 children.