P101 | A SINGLE CENTER RETROSPECTIVE EXPERIENCE ABOUT INFECTIONS AND ANTIMICROBIALS USE DURING CAR T-CELLS HOSPITALISATION FOR RELAPSED/REFRACTORY LYMPHOMA

Prophylactic and management strategies of infections in CAR T cells used for R/R lymphoma vary between institutions; we sought to describe here our experience in Pescara. Twenty-six lymphoma pts were treated from April 2021 to December 2024: 16 DLBCL, 5 PMBCL and 5 MCL received Axi-Cel (14 pts), Tisa-Cel (7 pts) and Brexu-Cel (5 pts). Median age at reinfusion was 58.5 years old. Twenty-four pts experienced CRS (G1 in 8 pts, G2 in 8 pts, G3 in 7 pts and G4 in 1 pt) and 13 pts had ICANS (5 pts G1, 4 pts G2, 3 pts G3 and 1 pt G4). Eighteen pts received Tocilizumab, 17 pts Dexamethasone, 10 pts received high dose Metilprednisolone, 4 pts had Anakinra. 25/26 pts were treated with antibiotics; a median of 3 different molecules were prescribed in the context of CRS. The most prescribed molecule was piperacilline-tazobactam in 1st line for 24 pts; follows meropenem used in 11 pts as 2nd line and vancomycin in 11 pts as 2nd antibiotic and in 8 pts as 3rd molecule. Three pts received Linezolid (as 2nd, 3rd and 4th molecule respectively), two pts fosfomycine (as 3rd and 4th molecule in association), one pt teicoplanine as 3rd molecule, 1 pt Ceftaroline as 5th antibiotic. Drugs like Cefiderocol and Vaborem were used 3 times: the latter was used as 4th and 5th molecule in 2 pts and Cefiderocol as 1st line in the context of known A.Baumannii and S. Maltophilia colonisation. Only 9 pts out of 25 had positive blood cultures (7 CoNS, 1 E.Faecium non VRE, 1 Salmonella spp). In 14 pts a CT scan has been done which in 4 cases showed the underlying disease and in the others mostly ground glass lesions and pleural effusions. Colonisation was found in 7 pts (Candida in 5 pts, C.Freundii in 1 pt, E. Faecium in 1 pt). For mold prophylaxis, 14 pts received Mycafungin, 6 pts Isavuconazole, 4 pts Amphotericine B and 2 pts did not receive an antifungal agent. Seven pts had a viral reactivation without clinical consequences (5 CMV, 1 EBV, 1 HHV6). At last follow up, 11/26 pts had died, 4 of them within 30 days from CAR T-cell infusion (3 deaths were disease-related, 1 death for MOF). Taking into consideration that only in few patients we had positive blood cultures, never associated with the colonizing microorganisms or multiresistant bacteria, and CT scan findings were aspecific and partly due to the concomitant CRS, it seems rational to advocate for a strategy of antibiotic stewardship during in CAR T-cell hospitalisation implementing descalation.