Tailoring antimicrobials in febrile neutropenia: using faster diagnostic and communication tools to improve treatment in the era of extensively resistant pathogens

ABSTRACT Febrile Neutropenia represents a medical emergency and the use of appropriate antimicrobial therapy is essential for a better outcome. Although being time-consuming, conventional cultures and antimicrobial susceptibility tests remain the golden standard practices for microbiology identification. Final reports are typically available within several days. Faster diagnostic tools, such as species identification trough Matrix Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) and molecular techniques might help to shorten time to diagnostic and also guide definitive therapy in this scenario. Here we present a case in which the use of a diagnostic molecular workflow combining MALDI-TOF and real-time PCR for relevant genes codifying antibiotic resistant integrated with instant communication report, led to a tailored and more appropriate treatment in a patient presenting with febrile neutropenia.

Microorganismos aislados de hemocultivos en niños con cáncer y neutropenia febril de alto riesgo en cinco hospitales de Santiago, Chile, período 2012-2015 / Microorganisms isolated from blood cultures in children with cancer and high-risk febrile neutropenia from five hospitals in Santiago, Chile, 2012-2015

Resumen Antecedentes: Los microorganismos aislados de hemocultivos (HC) en pacientes con neutropenia febril (NF) varían en el tiempo, siendo necesaria su vigilancia para orientar una terapia empírica adecuada. Objetivo: Identificar microorganismos aislados de HC y su perfil de resistencia (R) a antimicrobianos en niños con cáncer y NF de alto riesgo. Método: Estudio prospectivo, multicéntrico de episodios de NF de alto riesgo en pacientes bajo 18 años de edad, de cinco hospitales en Santiago de Chile, 2012-2015. Análisis de HC positivos. Resultados: Se analizaron 206 microorganismos en 185 episodios de NF de alto riesgo con HC positivos. Los aislados principales fueron bacilos gramnegativos (BGN) (46,6%) y cocáceas grampositivas (CGP) (45,1%) y los microorganismos más frecuentes Escherichia coli (22,8%), Staphylococcus coagulasa negativa (18,0%) y Klebsiella spp (16,5%). En resistencia (R) a antimicrobianos destaca: E. coli y Klebsiella spp 4,2 y 67,6% R a cefalosporinas de tercera generación (cefotaxima/ceftriaxona) respectivamente, 10,6 y 40,6% R a ciprofloxacina y 2,1 y 26,5% a amikacina, respectivamente. S. coagulasa negativa y S. aureus 86,4% y 22,2% R a oxacilina, Streptococcus grupo viridans 71% R a penicilina. Discusión: Este estudio actualiza la etiología y el perfil de R de microorganismos aislados en HC de niños con cáncer y NF de alto riesgo, herramienta esencial para el adecuado manejo de estos pacientes.

Background: Microorganisms isolated from blood cultures (BC) in patients with febrile neutropenia (NF) vary over time, requiring systematic monitoring to guide appropriate empirical therapy. Aim: To identify microorganisms isolated from BC and their antimicrobial resistance profile in children with cancer and high risk NF. Method: Prospective, multicenter study. The analysis included episodes of high-risk FN with positive BC in children under 18 years of age treated in five hospitals in Santiago, Chile, 2012-2015. Results: A total of 206 microorganisms were analyzed in 185 episodes of high-risk FN. The main isolates were Gram negative bacilli (46.6%) and Gram positive cocci (45.1%) and the most frequent microorganisms were Escherichia coli (22.8%), coagulase negative Staphylococcus (18.0%) and Klebsiella spp. (16.5%). Escherichia coli and Klebsiella spp showed 4.2% and 67.6% resistance to third generation cephalosporins (cefotaxime/ceftriaxone), 10.6% and 40.6% resistance to fluoroquinolones (ciprofloxacin) and 2.1% and 26.5% to amikacin, respectively. Coagulase negative Staphylococcus and Staphylococcus aureus had 86.4% and 22.2% resistance to oxacillin, Streptococcus viridans group had 71% resistance to penicillin. Discussion: This study updates the etiology and resistance profile of microorganisms isolated in BC from children with cancer and high risk FN, an essential tool for the adequate management of these patients.

Profilaxis con levofloxacina en pacientes neutropénicos / Levofloxacin prophylaxis in neutropenic patients

La profilaxis con fluorquinolonas ha demostrado utilidad en la prevención de infecciones en pacientes neutropénicos de alto riesgo. Nuestro objetivo fue describir y comparar las características clínicas, microbiológicas, terapéuticas y la evolución en pacientes durante el primer episodio de neutropenia febril, según hubieran o no recibido profilaxis con levofloxacina. Fue un estudio prospectivo observacional, que incluyó los episodios de internados por neutropenia febril, (febrero 1997 a noviembre 2014), y los primeros episodios en un mismo paciente en diferentes internaciones; en total fueron 946 episodios. En 821 el episodio de neutropenia febril fue de alto riesgo, y en 264 (27.9%) se administró profilaxis con levofloxacina. Este grupo estaba compuesto por mayor proporción de neutropenias febriles de alto riesgo (99.2% vs. 82.3%, p = 0.0001) y casos con trasplante de células progenitoras hematopoyéticas (67.8% vs. 29.3%, p = 0.0001) comparado con los que no recibieron profilaxis, y presentó una frecuencia similar de infecciones clínicamente documentadas pero una menor proporción de infecciones microbiológicamente documentadas (28.8% vs. 37.5%, p = 0.012). Las bacteriemias en el grupo con quimioprofilaxis fueron más frecuentemente causadas por organismos multirresistentes (OMR) (34.5% vs. 17.3%, p = 0.007) y por enterobacterias productoras de beta lactamasas de espectro extendido (19.0% vs. 3.8%, p = 0.0001). En ese grupo con profilaxis la proporción que recibió tratamiento antibiótico empírico adecuado fue menor (69.7% vs. 83.7%, p = 0.009). La evolución fue similar en ambos grupos. Sugerimos que cuando se observe un aumento en la frecuencia de infecciones por OMR en esta población se considere la interrupción de la profilaxis antibiótica con levofloxacina.

Fluorquinolone-prophylaxis has proven useful in preventing infections in high risk neutropenic patients. The objective of this study was to describe the clinical, microbiological and therapeutic characteristics, and outcome of patients in the first episode of febrile neutropenia, comparing those who received levofloxacin prophylaxis with those who didn't. It was a prospective observational study that included all the episodes of inpatients with febrile neutropenia (February 1997- November 2014), also including the first episode in a same patient in different hospitalizations. Of 946 episodes here included, 821 presented high risk febrile neutropenia. A total of 264 cases (27.9%) received levofloxacin prophylaxis. This group consisted of a higher proportion of high risk febrile neutropenia (99.2% vs. 82.3%, p = 0.0001) and patients that had received an hematopoietic stem cell transplant (67.8% vs. 29.3%, p = 0.0001) compared to those who didn't receive prophylaxis. Those who received levofloxacin prophylaxis presented a similar frequency of clinically diagnosed but a lower proportion of microbiologically documented infections (28.8% vs. 37.5%, p = 0.012) than those who didn´t receive prophylaxis. The episodes of bacteremia that occurred in the first group were more frequently caused by multidrug resistant bacteria (MDRB) (34.5% vs. 17.3%, p = 0.007) and by extended spectrum beta lactamase producing Enterobacteriaceae (19% vs. 3.8%, p = 0.0001). The group that received prophylaxis had a lower proportion of adequate empirical antibiotic treatment (69.7% vs. 83.7%, p = 0.009), with similar outcomes in both groups. We suggest that levofloxacin prophylaxis should be stopped whenever there is a rise in the frequency of MDRB infections in this population.

Rare severe mycotic infections in children receiving empirical caspofungin treatment for febrile neutropenia

ABSTRACTEmpirical antifungal therapy is most often given to patients with leukemia. However breakthrough fungal infections under antifungal therapy are not uncommon. Four children, with hematologic malignant disease developed mycotic breakthrough infections while on empirical caspofungin treatment for a median of 14 (range 11-19) days. Trichosporon asahii was detected in the blood culture of two patients and Geotrichum capitatum in the other two (one patient also had positive cerebrospinal fluid culture). Because the patients' clinical situation worsened, voriconazole was empirically added for two patients three and five days before the agent was detected. The first sterile blood culture was obtained 3-7 days of voriconazole treatment. All patients reached clear cultures but one patient died. One patient with central nervous system infection with G. capitatum had severe neurological sequelae. Very severe fungal infections can occur during empirical caspofungin therapy. Therefore, patients should be followed closely.

Aureobasidium pullulans infection in a patient with chronic lymphocytic leukemia

Saprophytic fungi are being increasingly recognized as etiologic agents of mycoses in immunosuppressed patients. We report a case of subcutaneous infiltration by Aureobasidium pullulans, likely due to traumatic inoculation, in a neutropenic patient during chemotherapy for chronic lymphocytic leukemia. The patient was treated with amphotericin B deoxycholate but was subsequently switched to itraconazole, which improved the lesion. This case highlights the importance of considering unusual fungal infections in critically ill patients such as those who are immunosuppressed due to chemotherapy. Diagnostic techniques and effective antifungal therapy have improved the prognosis of these cases.