Do high MICs predict the outcome in invasive fusariosis?

BACKGROUND

Invasive fusariosis (IF) affects mostly severely immunocompromised hosts and is associated with poor outcome. Since Fusarium species exhibit high MICs for most antifungal agents, this could explain the poor prognosis. However, a clear-cut correlation between MIC and outcome has not been established.

OBJECTIVE

To evaluate the correlation between MIC and outcome (6 week death rate) in patients with IF.

METHODS

We performed a multicentre retrospective study of patients with IF who received treatment and had MIC levels determined by EUCAST or CLSI for the drug(s) used during treatment. We compared the MIC50 and MIC distribution among survivors and patients who died within 6 weeks from the diagnosis of IF.

RESULTS

Among 88 patients with IF, 74 had haematological diseases. Primary treatment was monotherapy in 52 patients (voriconazole in 27) and combination therapy in 36 patients (liposomal amphotericin B + voriconazole in 23). The MIC50 and range for the five most frequent agents tested were: voriconazole 8 mg/L (range 0.5-64), amphotericin B 2 mg/L (range 0.25-64), posaconazole 16 mg/L (range 0.5-64), itraconazole 32 mg/L (range 4-64), and isavuconazole 32 mg/L (range 8-64). There was no difference in MIC50 and MIC distribution among survivors and patients who died. By contrast, persistent neutropenia and receipt of corticosteroids were strong predictors of 6 week mortality.

CONCLUSIONS

Our study did not show any correlation between MIC and mortality at 6 weeks in patients with IF.

Clinical Impact of Accelerate PhenoTM Rapid Blood Culture Detection System in Bacteremic Patients

BACKGROUND

Accelerate Pheno blood culture detection system (AXDX) provides identification (ID) and antimicrobial susceptibility testing (AST) results within 8h of blood culture growth. Limited data exists regarding its clinical impact. Other rapid platforms coupled with antimicrobial stewardship program (ASP) real-time notification (RTN) have shown improved length of stay (LOS) in bacteremia.

METHODS

A single-center, quasi-experimental study of adult bacteremic inpatients before/after AXDX implementation was conducted comparing clinical outcomes from 1 historical and 2 intervention cohorts (AXDX and AXDX+RTN). Primary outcome was LOS.

RESULTS

Of 830 bacteremic episodes, 188 (77%) of 245 historical and 308 (155 AXDX, 153 AXDX+RTN; 65%) of 585 intervention episodes were included. Median LOS was shorter with AXDX (6.3d) and AXDX+RTN (6.7d) compared to historical (8.1d; P=0.001). Achievement of optimal therapy (AOT) was more frequent (93.6% and 95.4%) and median time to optimal therapy (TTOT) was faster (1.3d and 1.4d) in AXDX and AXDX+RTN compared to historical (84.6%, P≤0.001 and 2.4d; P≤0.001) respectively. Median antimicrobial days of therapy (DOT) was shorter in both intervention arms compared to historical (6d each vs 7d; P=0.011). Median LOS benefit was most pronounced in patients with coagulase negative Staphylococcus bacteremia (5.5d and 4.5d vs 7.2d; P=0.003) in AXDX, AXDX+RTN, and historical cohorts respectively.

CONCLUSIONS

LOS, AOT, TTOT, and total DOT significantly improved after AXDX implementation. Addition of RTN did not show further improvement over AXDX and an already active ASP. These results suggest AXDX can be integrated into healthcare systems with an active ASP even without the resources to include RTN.

Outcomes of patients with invasive fusariosis who undergo further immunosuppressive treatments, is there a role for secondary prophylaxis?

BACKGROUND

Patients treated for invasive aspergillosis may relapse during subsequent periods of immunosuppression and should receive secondary prophylaxis. Little is known about the frequency of relapse and practices of secondary prophylaxis for invasive fusariosis (IF).

OBJECTIVES

Evaluate practices of secondary prophylaxis and the frequency of relapse in patients who survived IF and were exposed to subsequent periods of immunosuppression.

METHODS

Multicentre retrospective study of patients with haematological malignancies who developed IF, survived the initial fungal disease period, and were exposed to subsequent periods of immunosuppression.

RESULTS

Among 40 patients, 35 received additional chemotherapy and developed neutropenia (median, 24 days; range, 4-104), and five received glucocorticoids for the treatment of graft-vs-host disease. Overall, 32 patients received secondary prophylaxis (voriconazole in 24) for a median of 112 days (range, 12-468). IF relapsed in five patients (12.5%): 2/8 (25%) not on prophylaxis and 3/32 (9.4%) receiving prophylaxis. Among 28 patients with disseminated IF, relapse occurred in 2/2 (100%) not on prophylaxis and in 3/26 (11.5%) on prophylaxis (P = 0.03). All patients who relapsed IF died.

CONCLUSIONS

Patients with IF who survive the initial disease may relapse if exposed to subsequent episodes of immunosuppressive therapies. Secondary prophylaxis should be considered, especially if IF was disseminated.

1593. Recurrence of Clostridium difficile Infection in Multiple Myeloma Patients Receiving Prophylactic Oral Vancomycin or Oral Metronidazole vs. No Prophylaxis

Background

Multiple myeloma (MM) patients are at increased risk of Clostridium difficile infection (CDI) compared with the general population. In prior studies, 12–14% were diagnosed with CDI, and ~16% had recurrent CDI during subsequent treatments. Recent studies have shown that oral vancomycin is effective secondary prophylaxis for the prevention of recurrent CDI in the general population. This retrospective study examined if secondary prophylaxis with oral vancomycin or metronidazole is effective to prevent recurrent CDI in MM patients.

Methods

MM patients who tested positive for their first episode of CDI from January 2014–December 2016 were included, and the 3 months following the CDI diagnosis was reviewed. Patients who died, and those who did not receive additional chemotherapy or antibiotics during the 3-month review period were excluded. The patients were divided into 3 cohorts: (1) oral vancomycin as secondary prophylaxis, (2) oral metronidazole as secondary prophylaxis, and (3) no C. difficile prophylaxis.

Results

A total of 110 MM patients with a first episode of CDI were reviewed, six were excluded due to death and four were excluded due to no subsequent chemotherapy or antibiotics. This left 100 patients included for analysis. The median age was 62 years, range 34–81. 92 subjects (92%) had exposure to antibiotics and 76 (76%) received chemotherapy. A total of 38 (38%) received secondary prophylaxis: 16 (42%) with oral metronidazole and 22 (58%) with oral vancomycin. There was no significant difference in recurrent CDI in patients who received any secondary prophylaxis (7/38, 18.4%) and in those who received none (15/62, 24.2%), P = 0.46. Incidence of recurrent CDI in patients receiving oral vancomycin (3/22, 13.6%) was not significantly different from patients receiving oral metronidazole (4/16, 25%), P = 0.56. An analysis of risk factors for recurrent CDI showed no difference in recurrence in patients who received metronidazole vs. vancomycin as treatment for the initial CDI. Similar recurrent CDI occurred in patients who received antibiotics and those who received chemotherapy.

Conclusion

Secondary prophylaxis with either oral metronidazole or oral vancomycin did not reduce the incidence of recurrent CDI in MM patients.

Disclosures

All authors: No reported disclosures.

487. Severity and Clinical Outcomes of Clostridium difficile Infection Based on Toxin B Assay Results

Background

Clostridium difficile infection (CDI) remains a major health problem in the United States. The IDSA guidelines recommend using stool toxin assay as part of a multistep algorithm rather than nucleic acid amplification test (NAAT) alone. However, the clinical significance of toxin negative tests remains a subject of debate. We performed a prospective study in our institution to describe clinical outcomes of CDI based on the results of the stool toxin assay.

Methods

Our laboratory utilizes a 2-step algorithm, using glutamate dehydrogenase plus detection of toxin B by enzyme immunoassay (EIA) arbitrated by NAAT for testing stool samples submitted for C. difficile testing. The study was conducted between January and December 2017. Patients diagnosed with CDI based on laboratory results were divided into two groups based on toxin B assay results. Shotgun metagenomics was performed directly on stool specimens using Illumina NextSeq in a subset of patients. Chart reviews were performed to assess clinical outcomes. Our primary outcome was incidence of severe CDI and 30-day mortality.

Results

A total of 2,823 samples were submitted to the laboratory for testing for suspected CDI. Three hundred thirty-eight samples in 290 discrete patients were considered positive using the two step algorithm. Whole genome sequencing was performed on samples from 57 patients (Figure 1). Clinical outcome data were available for 53 patients. Thirty percent were on active chemotherapy. Thirty-four patients were toxin B positive (group 1), 19 were toxin B negative (group 2) by EIA. Hospital onset disease was seen in 10 (27%) of patients in group 1 vs. 7 (37%) in group 2 (P = 0.57). Thirty-day mortality was 3% in toxin positive vs. 5% in toxin negative groups (P = 0.67). Severe CDI was seen in 14 (41%) in group 1 vs. 8 (42%) in group 2 (P = 0.94). NAP 1 strain was detected in 10.5% of patients in group 2. Percentage of C. difficile reads on sequencing in fecal samples in group 1 (0.17%) was not significantly different from group 2 (0.24%) (P = 0.70, Figure 2).

Conclusion

In our cohort, detection of C. difficile toxin in stool samples was not associated with increased severity of disease. Our cohort has a higher prevalence of patients on active chemotherapy than previously studied cohorts.

Bioburden of C. difficile was not significantly different in toxin positive and negative disease.

Disclosures

All authors: No reported disclosures.

Possible Transfusion-Transmitted Babesia divergens-like/MO-1 Infection in an Arkansas Patient

A patient with asplenia and multiple red blood cell transfusions acquired babesiosis infection with Babesia divergens-like/MO-1 organisms and not Babesia microti, the common United States species. He had no known tick exposure. This is believed to be the first transfusion-transmitted case and the fifth documented case of B. divergens-like/MO-1 infection.

Malignancies, Particularly B-Cell Lymphomas, Are a Frequent Cause of Mortality in Human Immunodeficiency Virus-1 Patients Despite Highly Active Antiretroviral Therapy

Human immunodeficiency virus (HIV)-1-infected individuals are affected by diseases at rates above those of their HIV-negative peers despite the increased life expectancy of the highly active antiretroviral therapy era. We followed a cohort of approximately 2000 HIV-1-infected patients for 5 years. The most frequent cause of death in this HIV-1-infected cohort was malignancy, with 39% of all classified deaths due to cancer. Among the cancer deaths, B-cell lymphomas were the most commonly seen malignancy, representing 34% of all cancer deaths. These lymphomas were very aggressive with a median survival of <2 months from time of diagnosis.

[Knowledge and attitudes of ambulatory patients regarding various aspects of pharmacologic treatment]

Recognizing the patients believes and attitudes towards their disease and treatment as well as facilitating basic information are essential for a satisfactory compliance. In this respect, and in order to know the state of things, personal interviews were carried out following a pre-established protocol and evaluating the degree of acceptance of information oriented to the outpatient. Two hundred and seven questionnaires were collected. Populations mean age was 50 years, 60% were women and there was a high percentage of illiterate patients or with only primary school level (69.8%), with a medium-low social status (98%). In general, they were aware of the indication of treatment (80%) although 56% of patients did not know the consequences of a poor control of their disease. Seventy eight percent wished to receive more information and 147 (96%) patients preferred the physician as the provider of it. The opinion regarding the information leaflets oriented towards the outpatient was unanimously favorable being the most interesting aspects those regarding the instructions on the use of drugs and adverse effects. The educational level was the factor influencing most significantly the patient's attitude. We conclude saying that in order to carry out a pharmacological treatment educational program it is necessary to evaluate the knowledge, needs and attitudes of the population towards whom it is directed.