Weekly Screening for Multidrug-Resistant Organisms Identifies High Number of Colonizations in Patients Undergoing Stem Cell Transplantation

Introduction: Multidrug-resistant organisms (MDRO) are a challenge in patients undergoing stem cell transplant (SCT) which often result in an increase in mortality. To our knowledge, current literature defines only screening at the time of work-up for SCT-patients. The aims of the study were to assess the rate of MDRO colonization with weekly screening, rate of infection and the associated mortality in patients undergoing SCT. Patients and methods: Consecutive patients admitted at the SCT unit between January-18 to July-18 were reviewed in our institution. Screening consisted of rectal and perineal swab on admission and weekly until the date of discharge. In case of detection of MDRO , patients were isolated and infection control strategies were applied. Results: 41 patients were analysed, with 47 admissions, 6 patients had 2 admissions. The median duration of hospitalization was 27 days/patient (range 8-100). 168 rectal-and perineal swab were performed with a median of 3 swabs/patient (range 1-7). Patient characteristics are shown in Table 1. 36 patients (87%) spiked fever in a median of 8,5 days after admission (1-38days). 24,4% (n=10) had a positive screening: 2/10 patients at baseline and 8/10 patients (80%) were detected for the first time beyond baseline screen. Rate of MDRO colonization was 3% per week (95%CI 1.4-5.4). MDRO identified were : 4 patients with Extended-spectrum beta-lactamases producing E. Coli (ESBL-EC), Multidrug-resistant (MR) Pseudomonas aeruginosa (n=3), Vancomycin-resistant Enterococci (n=2) and 1 patient with carbapenem-resistant Citrobacter freundii. 6/10 patients developed MDRO infection (60%), all with previous MDRO positive detection: MR-Pseudomonas aeruginosa in urine culture (n=3) 2 treated with ceftolozane/tazobactam, 1 with meropenem+amikacin; ESBL-EC in urine culture (n=2) both treated with meropenem and 1 with Klebsiella pneumoniae carbapenemase in urine culture treated with ceftazidime/avibactam. The infection rate was 4,6% (95% CI 3.9-5.2). In 80% patients (n=8) antibiotic treatment was guided by positive screening, 3 patients were admitted to intensive care unit for sepsis. No mortality was associated to MDRO. In 76%of patients (n=28) screening was negative for MDRO. 24/28 (85%) spiked fever with a median of 10 days after admission (1-38days). None MDRO-infections in negative-screened patients were detected. Conclusions : Weekly screening for MDRO identified a high number of MDRO colonizations allowing to apply earl