Failure of Levofloxacin Prophylaxis to Alter Incidence of Neutropenic Fever in Multiple Myeloma Patients Undergoing Autologous Peripheral Blood Stem Cell Transplantation

Background: Patients (pts) undergoing autologous peripheral blood stem cell transplantation (PBSCT) experience prolonged neutropenia and are at high risk for infection. Current guidelines recommend antibacterial prophylaxis with fluoroquinolones (FQs) to mitigate this risk [Biol Blood Marrow Transplant 15: 1143-1238 (2009)]. Use of FQs appears to decrease the rates of neutropenic fever (NF), bacteremia, and sometimes mortality, but these series grouped together multiple hematologic disorders or were not restricted to pts undergoing PBSCT. There remains concern that FQs may promote the development of resistant bacterial organisms. Our institution adopted universal FQ prophylaxis in 2012. We directly compared the experience of consecutive multiple myeloma (MM) pts undergoing PBSCT before and after this change. Methods: We performed a retrospective analysis of all MM pts undergoing autologous PBSCT from 1/2010-3/2017. Prior to 4/2012, pts received routine GCSF starting at day +5, while afterward all pts received levofloxacin 500 mg orally daily starting day 0 until engraftment or first NF episode. All pts received Melphalan 200 mg/m2, based on actual body weight, administered on day −2. For those pts undergoing multiple PBSCTs—each transplant was treated as a separate event. Statistics were calculated using Fisher's exact test and Pearson's chi-squared test. Results: 311 pts undergoing 334 PBSCTs were reviewed. Median age at transplant was 62 years old, with 60% male. Use of FQ prophylaxis did not alter the rate of NF but did significantly decrease the rate of bacteremia, notably gram negative bacteremia. However, FQ prophylaxis did not alter mortality or length of stay. There was no significant increase in clostridium difficile (C diff) detection.Tabled 1No prophylaxisFQ prophylaxisTotal N97237Neutropenic fever73 (75%)166 (70%)P = .3375Bacteremia44 (45%)65 (27%)P = .0015Gram positive bacteremia23 (24%)51 (22%)P = .6614Gram negative bacteremia27 (28%)12 (5%)P < .0001FQ resistant gram negative1 (1%)10 (4%)P = .1868Anaerobic bacteremia4 (4%)6 (3%)P = .4842C diff within 30 days of discharge4 (4%)18 (8%)P = .2456Median duration of SCT admission (range)16 (1-47) days16 (11-15) daysP = .5486Mortality within 90 days after SCT1 (1%)6 (3%)P = .6780 Open table in a new tab Conclusions: Contrary to past findings, in this population of only MM pts, FQ prophylaxis was not associated with decreased NF or mortality but was associated with a reduction in gram negative bacteremia. The degree of benefit of FQ prophylaxis in SCT may depend on the pt risk profile, including the conditioning regimen, the type of SCT, and the underlying disease process.