Burnham JP, et al. - Researchers here retrospectively assessed if strain typing of Propionibacterium acnes could help to distinguish between infection and contamination in isolates recovered from the central nervous system (CNS) and prosthetic joints (PJs). In this work, for CNS infection, the predominant strain type was IA-1 and for PJ isolates, IB. In patients with CNS infections, strain type IA-1 was isolated more often, indicating a predilection of this strain type to cause CNS infection.