A 13-year-old girl with a history of a triplanar fracture of the right ankle, who was treated surgically with osteosynthetic material (MOS) removed at four months, whose surgical wound had never healed.
Two months after the removal of the SOM due to inflammatory changes in the ankle and the removal of purulent material with bad odor.
No signs of systemic inflammatory response were observed.
He received empirical dicloxacillin without improvement.
For this reason, surgical debridement was performed and a continuity defect of approximately 2.5 cm x 1.5 cm was found in the medial malleolar region, draining a friable and necrotic bone material.
Tissue samples were taken for culture and intravenous cefazolin was initiated empirically.
Gram stain showed gram-positive bacilli and culture showed growth of Bacillus spp., which was considered as contamination and continued with the prescribed treatment.
The patient persisted with drainage of sero-hematic secretion by the wound so a new surgical debridement was performed and the therapy was changed to intravenous clindamycin.
The tissue and bone samples showed growth of Gram-positive bacilli identified as Bacillus spp. without possibility of species identification or antimicrobial susceptibility pattern by the available method (VITEK 2 system).
The antibiogram performed by Kirby Bauer technique showed resistance to clindamycin, so it was decided to start intravenous vancomycin.
The strain was finally identified by the MALDI-TOF MS methodology (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) as Corynebacterium striatum.
Seven days after treatment with vancomycin, the wound persisted with secretion.
Ankle MRI showed a collection of soft tissues, periosteal edema, irregular cortical bone with a fistulous tract on the skin.
In the third surgical intervention the fibrotic fistula was corrected and new samples were taken for culture, in which growth of the same microorganism was obtained, also identified by MALDI-TOF technique as Corynebacterium striatum.
A manual antibiogram showed susceptibility to vancomycin, linezolid, daptomycin and imipenem, and resistance to clindamycin, cephalosporins, rifampicin, levofloxacin and cotrimazol.
Vancomycin doses were increased to trough levels of 10 ug/ml.
The clinical course after the last surgery and dose adjustment was satisfactory, with complete healing and secretion of the wound.
Vancomycin treatment was continued for 28 days and outpatient treatment was completed two more weeks with oral linezolid.
The patient was evaluated one month after surgery and the surgical wound was completely healthy, with no inflammatory signs and normal acute phase reactants.
