Her medical history included long term colonization by multi drug resistant Pseudomonas aeruginosa and Burkholderia multivorans. She had undergone bilateral lung transplantation when she was 19 years old, and 2 years later, she developed progressive chronic lung allograft dysfunction (CLAD) with a bronchiolitis obliterans syndrome (BOS) stage Tucidinostat concentration 3 since the last 6 months and a respiratory insufficiency requiring oxygen supplement 2 months before the admission. The immunosuppressive regimen on admission consisted of tacrolimus (trough level around 8 to 10 ng/ml), mycophenolate mofetil (500 mg twice daily) and azithromycin 250 mg daily for BOS

for more than one year. The worsening of respiratory function was associated with the persistence of Pseudomonas aeruginosa and Burkholderia multivorans colonization along with appearance of Aspergillus fumigatus. During hospitalization in the ICU, probabilistic PND-1186 antibiotherapy consisted of an association of ceftazidime,

tobramycin and inhaled colistin. After an initial improvement, despite she still required oxygenotherapy device and intermittent noninvasive ventilation support, her respiratory function worsened on January 2011. A sputum sample was collected on January 7th, in which multiresistant Pseudomonas aeruginosa and Burkholderia multivorans were isolated on chocolate Poly ViteX agar (bioMérieux, Marcy l’Etoile, France) and cepacia agar (AES laboratory, Combourg, France), respectively. An atypical gram positive strain was isolated at 105 CFU/ml on Columbia CNA agar plate. A treatment with ceftazidime, temocillin and inhaled colistin was started again. Her respiratory function continued

to deteriorate and she died after 2 months in a septic clinical condition. Results Phenotypic features The gram positive mafosfamide strain was isolated on Columbia colistin-nalidixic acid CNA agar with 5% sheep blood (bioMérieux), after 24 hours of incubation at 37°C with 5% CO2 (Figure 1A,1B,1C). It also grew on COS medium at 29°C after 24 hours. The colonies are 0.1-0.2 mm in diameter. The isolate was an aerobic, yellow pigmented (Figure 1A), rod-shaped, non-motile, oxidase negative and catalase positive bacterium. This strain was able to grow in microaerophillic atmosphere but not in anaerobic atmosphere. It also grew very weakly at a salt concentration of up to 10% after 48 hours of incubation. As the spectrum for Microbacterium yannicii was not available in the Bruker database at the time of our strain isolation, we were not able to identify correctly and after the addition of Microbacterium yannicii G72 type strain spectrum in our local database, our strain was identified as Microbacterium yannicii with a low score (Score 1.3). Hence, we proceeded with 16SrRNA sequencing for precise identification.