Interventions to optimize antimicrobial stewardship.

Developing and improving an antimicrobial stewardship program successfully requires evaluation of numerous factors. As technology progresses and our understanding of antimicrobial resistance grows, careful consideration should be taken to ensure that a program meets the needs of the institution and is achievable given the available resources. In this review, we explore fundamental initiatives and strategies for both new and established antimicrobial stewardship programs, including the specific areas to target and key elements required for sustainable implementation.

Frequency, risk factors, and outcomes of vancomycin-resistant Enterococcus colonization and infection in patients with newly diagnosed acute leukemia: different patterns in patients with acute myelogenous and acute lymphoblastic leukemia.

OBJECTIVE To determine the frequency, risk factors, and outcomes for vancomycin-resistant Enterococcus (VRE) colonization and infection in patients with newly diagnosed acute leukemia. DESIGN Retrospective clinical study with VRE molecular strain typing. SETTING A regional referral center for acute leukemia. PATIENTS Two hundred fourteen consecutive patients with newly diagnosed acute leukemia between 2006 and 2012. METHODS All patients had a culture of first stool and weekly surveillance for VRE. Clinical data were abstracted from the Intermountain Healthcare electronic data warehouse. VRE molecular typing was performed utilizing the semi-automated DiversiLab System. RESULTS The rate of VRE colonization was directly proportional to length of stay and was higher in patients with acute lymphoblastic leukemia. Risk factors associated with colonization include administration of corticosteroids (P=0.004) and carbapenems (P=0.009). Neither a colonized prior room occupant nor an increased unit colonization pressure affected colonization risk. Colonized patients with acute myelogenous leukemia had an increased risk of VRE bloodstream infection (BSI, P=0.002). Other risk factors for VRE BSI include severe neutropenia (P=0.04) and diarrhea (P=0.008). Fifty-eight percent of BSI isolates were identical or related by molecular typing. Eighty-nine percent of bloodstream isolates were identical or related to stool isolates identified by surveillance cultures. VRE BSI was associated with increased costs (P=0.0003) and possibly mortality. CONCLUSIONS VRE colonization has important consequences for patients with acute myelogenous leukemia undergoing induction therapy. For febrile neutropenic patients with acute myelogenous leukemia, use of empirical antibiotic regimens that avoid carbapenems and include VRE coverage may be helpful in decreasing the risks associated with VRE BSI.

Rapidly Fatal Internal Carotid Artery Mycotic Aneurysm Rupture in a Rheumatoid Patient Taking a TNF-α Inhibitor: Case Report and Literature Review.

OBJECT: Tumor necrosis factor (TNF)-α inhibitors are effective at treating certain inflammatory and autoimmune disorders. They are generally safe; potential adverse events include infections (bacterial, fungal, and viral), congestive heart failure exacerbations, and the potential for demyelinating diseases and possibly certain malignancies. We present the first documented case of fungal internal carotid artery (ICA) mycotic aneurysm in a patient being treated with a TNF-α inhibitor. We also review the literature on infections with TNF-α inhibition and the management of previously reported fungal ICA mycotic aneurysm cases. CASE DESCRIPTION: A 76-year-old woman with rheumatoid arthritis, treated with etanercept and methotrexate, presented with a 2-week history of left temporal headaches. She was treated empirically for giant cell arteritis (GCA) with oral prednisone, which provided no symptom relief. She was subsequently hospitalized for a superficial temporal artery biopsy, which was negative for GCA. She returned 2 weeks later after experiencing a left thromboembolic ischemic stroke. She had an acute neurologic decline, and a head computed tomography scan showed diffuse subarachnoid hemorrhage from a ruptured left fusiform paraclinoid ICA aneurysm. She was taken emergently for a craniotomy for clip-wrapping of the aneurysm, but intraoperative ultrasound revealed poor flow in the left anterior cerebral circulation and a complete infarct of the left-sided anterior circulation. The family withdrew care and the patient died. Postmortem analysis demonstrated fungi consistent with Aspergillus invading the necrotic left ICA. CONCLUSIONS: Although fungal mycotic aneurysms of the ICA are rare, their incidence may increase with the expanded use of immunosuppressive medications. Patients with rheumatoid arthritis who take potent immunosuppression regimens may be prime candidates for mycotic aneurysms because they often have two favoring conditions: atherosclerosis and immunosuppression. These ICA aneurysms carry a high mortality rate, so early diagnosis and aggressive therapy, potentially by endovascular trapping/vessel occlusion coupled with long-term antifungal therapy, is essential.

Central venous catheter-associated Nocardia bacteremia in cancer patients.

Central venous catheters, often needed by cancer patients, can be the source of Nocardia bacteremia. We evaluated the clinical characteristics and outcomes of 17 cancer patients with Nocardia bacteremia. For 10 patients, the bacteremia was associated with the catheter; for the other 7, it was a disseminated infection. N. nova complex was the leading cause of bacteremia. Nocardia promoted heavy biofilm formation on the surface of central venous catheter segments tested in an in vitro biofilm model. Trimethoprim- and minocycline-based lock solutions had potent in vitro activity against biofilm growth. Patients with Nocardia central venous catheter-associated bloodstream infections responded well to catheter removal and antimicrobial drug therapy, whereas those with disseminated bacteremia had poor prognoses.

Transfusion-related Plasmodium ovale malaria complicated by acute respiratory distress syndrome (ARDS) in a non-endemic country.

46year old female presented with a one week history of high grade fever, chills, cough, and severe nausea. The patient had been admitted a month earlier with severe lower gastrointestinal bleeding from hemorrhoids necessitating transfusion of 7 units of packed red blood cells. Initial work-up was unremarkable. Because of persistent symptoms, the patient was admitted 2 days later. Malaria smear was positive. Due to the severity of her symptoms, she was managed as falciparum malaria and was started on intravenous quinine and oral doxycycline. On the second day of treatment the patient developed respiratory failure, requiring intubation and ventilatory support with new bilateral pulmonary infiltrates. Antimalarial treatment was continued for a total of 7 days followed by primaquine for 14 days once the blood smear results revealed Plasmodium ovale infection. The patient remained intubated in the intensive care unit (ICU) for 16 days, and was later extubated successfully with a clear chest x-ray after a total of one month hospitalization. To our knowledge, this is the first case of acute respiratory distress syndrome (ARDS) secondary to blood transfusion related P. ovale malaria infection in a non-endemic country.