Results
A total of 219 patients were included in the study. One hundred and twenty-four patients had undergone autologous stem cell transplant (ASCT) and 95 patients underwent allogeneic stem cell transplant (AlloSCT). The first 100 patients undergoing transplant received antibiotic prophylaxis and the next 119 patients did not receive antibiotic prophylaxis. All patients received levofloxacin as prophylaxis except 11 children less than 7 year of age who received amoxicillin prophylaxis. The median age of the patients in ‘no-prophylaxis group’ was 45 years (range- 2 to 68 years) and in the ‘prophylaxis group’ it was 34.5 years (range -1 to 68 years). In both cohorts, myeloma was the most common diagnosis of patients undergoing ASCT. In AlloSCT group most common diagnoses were leukemia and hemoglobinopathy. The median CD34 dose was comparable in both the cohorts (5x 106 /kg vs 3.91 x 106/kg; p=0.111). Median neutrophil engraftment occurred at 11 days in the no prophylaxis group and at 12 days in prophylaxis group (Table 1). There was no difference in the median duration of hospital stay. There was no significant difference in other baseline characteristics (Table 1).
Both groups had comparable duration of fever. However, documented infection were significantly lower in patients who received antibiotic prophylaxis (29% vs 42.9%; p=0.034). The patients who did not receive antibiotic prophylaxis had higher rates of gram negative (34.5% vs 22%; p=0.043) and CRE sepsis (21% vs 1%; p=0.001) but there was no difference in the rates of gram-positive sepsis or BSI (Table 2). We did not observe any clostridium difficile infection.
In patients undergoing ASCT, number of febrile episodes, duration of fever, documented infections, BSI and gram-positive BSI were not different in prophylaxis vs no- prophylaxis group. However, GNB infection and carbapenem resistance were significantly lower in prophylaxis group. Despite this, overall mortality remained same in both groups.
In patients undergoing AlloSCT, number of febrile episodes, duration of fever, documented infections, gram-positive or gram-negative BSI was not different in prophylaxis vs no-prophylaxis group. However, carbapenem resistance was significantly lower in prophylaxis group (2% vs 23.9%). This contributed to major mortality difference in AlloSCT group (vs ASCT) in patients who did not receive antibiotic prophylaxis.
Transplant related mortality (TRM) was 8.2% for all patients. In ASCT group 7 (5.6%) patients died while in Allo SCT group 11 (11.5%) patients died. Antibiotic prophylaxis was not associated with reduction in mortality (p=0.258) in both ASCT and Allo SCT groups (Table 2).