Outcomes of Partial Oral Antibiotic Treatment for Complicated Staphylococcus aureus Bacteremia in People Who Inject Drugs.

BACKGROUND: Staphylococcus aureus represents the leading cause of complicated bloodstream infections among persons who inject drugs (PWID). Standard of care (SOC) intravenous (IV) antibiotics result in high rates of treatment success but are not feasible for some PWID. Transition to oral antibiotics may represent an alternative treatment option. METHODS: We evaluated all adult patients with a history of injection drug use hospitalized from January 2016 through December 2021 with complicated S. aureus bloodstream infections, including infective endocarditis, epidural abscess, vertebral osteomyelitis, and septic arthritis. Patients were compared by antibiotic treatment (standard of care intravenous [SOC IV] antibiotics, incomplete IV therapy, or transition from initial IV to partial oral) using the primary composite endpoint of death or readmission from microbiologic failure within 90 days of discharge. RESULTS: Patients who received oral antibiotics after an incomplete IV antibiotic course were significantly less likely to experience microbiologic failure or death than patients discharged without oral antibiotics (P < .001). There was no significant difference in microbiologic failure rates when comparing patients who were discharged on partial oral antibiotics after receiving at least 10 days of IV antibiotics with SOC regimens (P > .9). CONCLUSIONS: Discharge of PWID with partially treated complicated S. aureus bacteremias without oral antibiotics results in high rates of morbidity and should be avoided. For PWID hospitalized with complicated S. aureus bacteremias who have received at least 10 days of effective IV antibiotic therapy after clearance of bacteremia, transition to oral antibiotics with outpatient support represents a potential alternative if the patient does not desire SOC IV antibiotic therapy.

Experience with dalbavancin for long-term antimicrobial suppression of left ventricular assist device infections.

BACKGROUND: Left ventricular assist devices (LVAD) are a common strategy for management of end-stage heart failure. LVADs carry a risk of infection of the implanted device components, and skin flora are commonly implicated. Long-term antibiotics may be needed for management of deep device infection or recurrent superficial infections. In appropriately selected patients, dalbavancin can be a feasible option given its extended dosing interval. METHODS: This is a retrospective, single-center review of patients presenting with an LVAD infection between January 2011 and November 2022, where management included the use of dalbavancin. Data regarding LVAD placement, details of index infection, dalbavancin use and outcomes was obtained from chart review, and documented in a RedCap database. RESULTS: The mean time from LVAD placement to index infection was 131.6 weeks (standard deviation 87.2 weeks). The most common targeted organism was Corynebacterium striatum in six of 10 patients. Index infection presented as deep driveline infection in four patients and recurrent superficial driveline infection in three patients. Five patients had a concurrent bloodstream infection. Dalbavancin was discontinued in two patients due to breakthrough infection, with one patient requiring surgical intervention. No drug-related adverse events were noted. CONCLUSION: Dalbavancin is an attractive option in the management of long-term LVAD infection in patients for whom alternative oral or parenteral antibiotics are not a feasible option. Additional studies are needed to determine the optimal dosing of dalbavancin in this setting, and to study adverse events and long-term outcomes of dalbavancin.

Novel agents in the treatment of invasive fungal infections in solid organ transplant recipients.

PURPOSE OF REVIEW: Recipients of solid organ transplants (SOTs) suffer a significant burden of invasive fungal infections (IFIs). The emergence of drug-resistant fungi and toxicities of currently used antifungal agents as well as drug-drug interactions with immunosuppressants make their treatment challenging. This review discusses selected novel antifungal agents in the development pipeline that can currently be used through clinical trials or may be commercially available in the near future. RECENT FINDINGS: These agents in development have novel pharmacokinetics and pharmacodynamics, expanded spectra of activity and excellent safety profiles. SUMMARY: The properties of novel antifungal agents have the potential to expand the therapeutic options for IFIs in recipients of SOTs.

Disseminated cytomegalovirus infection with bilateral adrenal pseudotumors masquerading as recurrent hematologic malignancy.

BACKGROUND: Mass-like lesions are an uncommon presentation of cytomegalovirus (CMV) disease. CASE: We report on a case of disseminated CMV disease with bilateral adrenal pseudotumors in a patient with a history of acute leukemia in remission. CONCLUSION: In the settings of advanced cancer therapy and organ transplantation, a high index of suspicion for CMV should be maintained for mass-like disease.

Risk Factors, Management, and Outcomes of Pyogenic Liver Abscess in a US Safety Net Hospital.

BACKGROUND: The causes and management of pyogenic liver abscess (PLA) have undergone multiple changes over the past decades. It is a relatively rare disease in the USA, and its incidence rate in the USA is increasing. The last US community hospital experience of PLA was published in 2005. We performed a retrospective study of patients admitted with PLA to an urban safety net hospital. AIMS: To ascertain risk factors, management approaches, and outcomes of PLA. METHODS: Electronic medical record was queried for diagnosis codes related to PLA during the years 2009-2018. Clinical information was compiled in an electronic database which was later analyzed. Main study outcomes were in-hospital mortality, 30-day readmission rate, and intensive care utilization rate. RESULTS: A total of 77 patients with PLA were admitted in the study period. Most common risk factors were diabetes mellitus (23.4%), previous liver surgery (20.7%), and hepatic malignancy (16.9%). 89% of patients were treated with percutaneous drainage or aspiration, and surgical drainage was reserved for other with other indications for laparotomy. In-hospital mortality, 30-day readmission, and intensive care utilization rates were 2.6%, 7% and 22%, respectively. Median length of stay was 11 days (inter-quartile range 7). Rate of antimicrobial resistance in abscess fluid cultures was 40%; 13 cases of Klebsiella pneumoniae liver abscess were noted in our cohort, most of whom were Hispanic or Asian. CONCLUSIONS: PLA was principally managed by percutaneous drainage or aspiration with good outcomes. Further studies investigating the racial predilection of K. pneumoniae liver abscesses could reveal clues to its pathogenesis.

Escalating Surgical Treatment for Left Ventricular Assist Device Infection and Expected Mortality: Clinical Risk Prediction Score.

BACKGROUND: Left ventricular assist devices (LVAD) improve survival for patients with cardiac failure, but LVAD specific infections (VSI) remain a challenge with poorly understood predictive risk factors. Furthermore, the indications and utility of escalating medical treatment to surgical debridement and potential flap reconstruction are not well-characterized. STUDY DESIGN: A retrospective review of consecutive patients undergoing primary LVAD implantation at a tertiary academic center was performed. The primary outcomes measures were 90-day and overall mortality after VSI. Cox proportional hazards regression was used to generate a risk-prediction score for mortality. RESULTS: Of the 760 patients undergoing primary LVAD implantation, 255 (34%) developed VSI; of these 91 (36%) were managed medically, 134 (52%) with surgical debridement, and 30 (12%) with surgical debridement and flap reconstruction. One-year survival after infection was 85% with median survival of 2.40 years. Factors independently associated with increased mortality were diabetes (hazard ratio (HR) 1.44, p=0.04), methicillin-resistant Staphylococcus aureus infection (HR 1.64, p=0.03), deep space (pump pocket/outflow cannula) involvement (HR 2.26, p<0.001) and extra-corporeal membrane oxygenation after LVAD (HR 2.52, p<0.01. Factors independently associated with decreased mortality were flap reconstruction (HR 0.49, p=0.02) and methicillin-sensitive Staphylococcus aureus infection (HR 0.63, p=0.03). A clinical risk prediction score was developed using these factors and showed significant differences in median survival, which was 5.67 years for low-risk (score 0-1), 3.62 years for intermediate-risk (score 2), and 1.48 years for high-risk (score >3) (p<0.001) patients. CONCLUSIONS: We developed a clinical risk prediction score to stratify VSI patients. In selected cases, escalating surgical treatment was associated with increased survival. Future work is needed to determine if early surgical debridement and flap reconstruction can alter outcomes in select cases of VSI.

Clinical characteristics, microbiology and outcomes of a cohort of patients treated with ceftolozane/tazobactam in acute care inpatient facilities, Houston, Texas, USA.

Background: Ceftolozane/tazobactam is a ß-lactam/ß-lactamase inhibitor combination with activity against a variety of Gram-negative bacteria, including MDR Pseudomonas aeruginosa. This agent is approved for hospital-acquired and ventilator-associated bacterial pneumonia. However, most real-world outcome data come from small observational cohorts. Thus, we sought to evaluate the utilization of ceftolozane/tazobactam at multiple tertiary hospitals in Houston, TX, USA. Methods: We conducted a multicentre retrospective study of patients receiving at least 48 h of ceftolozane/tazobactam therapy from January 2016 through to September 2019 at two hospital systems in Houston. Demographic, clinical and microbiological data were collected, including the infecting bacterial isolate, when available. The primary outcome was composite clinical success at hospital discharge. Secondary outcomes included in-hospital mortality and clinical disposition at 14 and 30 days post ceftolozane/tazobactam initiation. Multivariable logistic regression analysis was used to identify predictors of the primary outcome and mortality. Recovered isolates were tested for susceptibility to ceftolozane/tazobactam and underwent WGS. Results: A total of 263 patients were enrolled, and composite clinical success was achieved in 185 patients (70.3%). Severity of illness was the most consistent predictor of clinical success. Combination therapy with ceftolozane/tazobactam and another Gram-negative-active agent was associated with reduced odds of clinical success (OR 0.32, 95% CI 0.16-0.63). Resistance to ceftolozane/tazobactam was noted in 15.4% of isolates available for WGS; mutations in ampC and ftsI were common but did not cluster with a particular ST. Conclusions: Clinical success rate among this patient cohort treated with ceftolozane/tazobactam was similar compared with previous experiences. Ceftolozane/tazobactam remains an alternative agent for treatment of susceptible isolates of P. aeruginosa.

The burden of Arcanobacterium haemolyticum pharyngitis: A systematic review and management algorithm.

INTRODUCTION: Arcanobacterium haemolyticum causes pharyngotonsillitis in children and young adults. It is rarely isolated in pharyngeal swabs as testing for it is not routine. Data on complications, management, and antibiotic susceptibility testing is limited. We sought to review the available literature on the presentation and management of A. haemolyticum pharyngotonsillitis in this age group. METHODS: A systematic review of eligible studies reporting pharyngotonsillitis and related complications in children and young adults caused by A. haemolyticum was conducted. Literature from case reports, case series, and available cohorts was compiled. Data were analyzed using descriptive statistics. RESULTS: The initial database search yielded 63 articles, after applying exclusion criteria 17 studies were included. 191 patients were identified with a median age of 16.5 years. The most common presentation was throat pain reported in 93.7% of patients. Tonsillar exudates, fever at presentation and rash were present in more than half of the reviewed cases. The diagnosis was established by a positive culture on a pharyngeal swab in 98.8% of swabs collected. Complications described included peritonsillar abscesses, Lemierre's syndrome, pneumonia, and sepsis. Penicillin was the first line antibiotic in 81% of patients followed by macrolides in 19 patients (18%). CONCLUSIONS: A. haemolyticum occurs in children and young adults and may result in complications. Our review supports its susceptibility to penicillin. We suggest a diagnostic and management algorithm to guide clinicians in targeted testing and aid with decision making regarding timely and appropriate antibiotic therapy, in an effort to reduce the burden of its complications.