Fig. 1

Radiological and microbiological findings. A, B MRI showed irregular bone destruction at the L4 vertebral body endplate (white arrow) with a T2-weighted image (B) and a lesion with low T1 (A) and high T2 intensity (B) at the L4 vertebral body and L4–L5 intervertebral disc (red and yellow arrows). C–E Gram staining (×1000) revealed Gram-positive rods (yellow arrow) (C). Non-hemolytic and circular white shiny colonies were observed (D). The susceptibility testing of the isolates from blood culture using the E-test® (bioMérieux) revealed susceptibility to penicillin and ampicillin, with MICs of less than 0.016 and 0.016 µg/mL, respectively, according to the Clinical and Laboratory Standards Institute criteria (M100-S31) (E). F, G The MALDI spectrum of the isolate obtained from blood (F) and pus (G) revealed dominant peaks at 3494, 3713, 6989, and 7427 m/z and 3495, 3714, 6991, and 7429 m/z, respectively. These peaks were not seen for other Cutibacterium species, including C. acnes