Antimicrobials in patients with hematologic malignancies and recipients of hematopoietic cell transplantation and other cellular therapies.

BACKGROUND: Appropriate use of antimicrobials for hematologic malignancy, hematopoietic stem cell transplant recipients, and other cellular therapies is vital, with infection causing significant morbidity and mortality in this unique population of immunocompromised hosts. However, often in this population the choice and management of antimicrobial therapy is complex. When selecting an antimicrobial agent, key considerations include the need for dose adjustments due to renal or hepatic impairment, managing drug interactions, the potential for additive drug toxicity among those receiving polypharmacy and therapeutic drug monitoring. Other factors include leveraging pharmacodynamic principles to enable optimization of directed therapy against challenging pathogens, as well as judicious use of antimicrobials to limit drug resistance and adverse drug reactions. SUMMARY: This review summarizes the clinical considerations for commonly used antimicrobials in this setting, including antibacterial, antiviral, and antifungal agents.

Antiretroviral Regimen and Pregnancy Outcomes of Women Living with HIV in a US Cohort.

Women who are pregnant and living with HIV have traditionally been excluded from clinical trials regarding new pharmacotherapy. Immediate initiation of antiretroviral therapy (ART) is recommended for women who are pregnant and living with HIV. Integrase inhibitors (INSTIs) are first-line recommended agents as they lead to more rapid HIV viral load reduction. We conducted a retrospective study of women who are pregnant and living with HIV who received prenatal care at the University of Washington. Mothers were categorized by ART class: INSTI, protease inhibitors (PI), and non-nucleoside reverse transcriptase inhibitors (NNRTI). Chi-square and t-tests were used for the analysis of baseline characteristics, and generalized estimating equations were used to adjust for HIV viral suppression between groups. There were a total of 234 mother-infant pairs whose pregnancies progressed beyond 20 weeks. The study demonstrated that women on INSTI regimens were more likely to have a shorter time to viral load suppression than women on NNRTI regimens. Additionally, seven congenital anomalies were identified in this cohort, none of which were neural tube defects. There was no perinatal transmission of HIV to any of the infants. This small cohort of women provides high-quality data regarding the safety and efficacy of INSTI use for both mothers and infants in resource-rich settings.

Ultrasonography in the Evaluation of Pediatric Chest "Masses": When to Consider?

Thoracic ultrasound is radiation-free, easily available, portable modality with added advantage of real-time assessment. It is useful in mediastinal lesions and peripheral lung, pleural and chest wall masses. Not only is it a valuable modality in differentiating solid from cystic lesion, it can also depict internal architecture without the use of contrast material. The added advantages of its use in children are the lack of ionizing radiation, and no need for sedation or general anesthesia in most cases. Although it has its limitations with a longer learning curve, it can act as a second-line modality to chest radiograph and adjunctive modality to CT in cases of a thoracic mass in a child.

Postprescription Review With Threat of Infectious Disease Consultation and Sustained Reduction in Meropenem Use Over Four Years.

BACKGROUND: Following a meropenem shortage, we implemented a postprescription review with feedback (PPRF) in November 2015 with mandatory infectious disease (ID) consultation for all meropenem and imipenem courses > 72 hours. Providers were made aware of the policy via an electronic alert at the time of ordering. METHODS: A retrospective study was conducted at the University of Washington Medical Center (UWMC) and Harborview Medical Center (HMC) to evaluate the impact of the policy on antimicrobial consumption and clinical outcomes pre- and postintervention during a 6-year period. Antimicrobial use was tracked using days of therapy (DOT) per 1000 patient-days, and data were analyzed by an interrupted time series. RESULTS: There were 4066 and 2552 patients in the pre- and postintervention periods, respectively. Meropenem and imipenem use remained steady until the intervention, when a marked reduction in DOT/1000 patient-days occurred at both hospitals (UWMC: percentage change -72.1% (95% confidence interval [CI] -76.6, -66.9), P < .001; HMC: percentage change -43.6% (95% CI -59.9, -20.7), P = .001). Notably, although the intervention did not address antibiotic use until 72 hours after initiation, there was a significant decline in meropenem and imipenem initiation ("first starts") in the postintervention period, with a 64.9% reduction (95% CI 58.7, 70.2; P < .001) at UWMC and 44.7% reduction (95% CI 28.1, 57.4; P < .001) at HMC. CONCLUSIONS: PPRF and mandatory ID consultation for meropenem and imipenem use beyond 72 hours resulted in a significant and sustained reduction in the use of these antibiotics and notably impacted their up-front usage.

Tocilizumab in hospitalized patients with COVID-19: Clinical outcomes, inflammatory marker kinetics, and safety.

Coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 causes substantial morbidity. Tocilizumab, an interleukin-6 receptor antagonist, might improve outcomes by mitigating inflammation. We conducted a retrospective study of patients admitted to the University of Washington Hospital system with COVID-19 and requiring supplemental oxygen. Outcomes included clinical improvement, defined as a two-point reduction in severity on a six-point ordinal scale or discharge, and mortality within 28 days. We used Cox proportional-hazards models with propensity score inverse probability weighting to compare outcomes in patients who did and did not receive tocilizumab. We evaluated 43 patients who received tocilizumab and 45 who did not. Patients receiving tocilizumab were younger with fewer comorbidities but higher baseline oxygen requirements. Tocilizumab treatment was associated with reduced C-reactive protein, fibrinogen, and temperature, but there were no meaningful differences in time to clinical improvement (adjusted hazard ratio [aHR], 0.92; 95% confidence interval [CI], 0.38-2.22) or mortality (aHR, 0.57; 95% CI, 0.21-1.52). A numerically higher proportion of tocilizumab-treated patients had subsequent infections, transaminitis, and cytopenias. Tocilizumab did not improve outcomes in hospitalized patients with COVID-19. However, this study was not powered to detect small differences, and there remains the possibility for a survival benefit.

Transplant tourism complicated by life-threatening New Delhi metallo-ß-lactamase-1 infection.

Transplant tourism, which is the practice of traveling to other countries for transplant, continues to be a major problem worldwide. We describe a patient who traveled to Pakistan and underwent commercial kidney transplant. He developed life-threatening infections from New Delhi metallo-ß-lactamase-1-producing Enterobacter cloacae and Rhizopus oryzae, resulting in a necrotizing kidney allograft infection and subsequent external iliac artery rupture. He survived after a prolonged course of nonstandardized antimicrobial therapy, including a combination of aztreonam and ceftazidime-avibactam, and aggressive surgical debridement with allograft nephrectomy. The early timing of infection with these unusual organisms localized to the allograft suggests contamination and substandard care at the time of transplant. This case highlights the challenges of caring for these infections and serves as a cautionary tale for the potential complications of commercial transplant tourism.

Multicenter Evaluation of Ceftolozane/Tazobactam for Serious Infections Caused by Carbapenem-Resistant Pseudomonas aeruginosa.

A multicenter, retrospective study of patients infected with carbapenem-resistant Pseudomonas aeruginosa who were treated with ceftolozane/tazobactam was performed. Among 35 patients, pneumonia was the most common indication and treatment was successful in 26 (74%). Treatment failure was observed in all cases where isolates demonstrated ceftolozane-tazobactam minimum inhibitory concentrations ≥8 µg/mL.

Evaluation of Posaconazole Serum Concentrations from Delayed-Release Tablets in Patients at High Risk for Fungal Infections.

The purpose of our study was to determine the frequency of patients who achieved a therapeutic drug level after receiving posaconazole (PCZ) delayed-release tablets (DRT) for prophylaxis or treatment of invasive fungal infections (IFIs) and to examine the effect of demographic traits and treatment characteristics on PCZ serum levels. A retrospective single-center study was conducted on high-risk inpatients at the University of Washington Medical Center (UWMC) that had received PCZ and obtained PCZ serum levels for either treatment or prophylaxis between 1 August 2014 and 31 August 2015. High-risk patients were defined as those undergoing chemotherapy for a primary hematologic malignancy and those undergoing hematopoietic cell transplantation (HCT) or solid organ transplantation. Serum trough concentrations of ≥700 µg/liter and ≥1,000 µg/liter were considered appropriate for prophylaxis and treatment, respectively. The most frequent underlying medical condition was a hematological malignancy (43/53, 81%). Twenty-six of 53 patients (49%) received PCZ for prophylaxis; the rest received PCZ for treatment. A total of 37/53 (70%) patients had PCZ serum levels of ≥700 µg/liter regardless of indication, including 22/26 (85%) that received PCZ for prophylaxis. Of the patients that received PCZ for treatment, only 12/27 (44%) had PCZ serum levels of ≥1,000 µg/liter. The odds of having therapeutic PCZ serum levels were not statistically different in patients with a weight of ≥90 kg, a diarrhea grade of ≥2, a mucositis grade of ≥2, or poor dietary intake. However, the odds of having therapeutic PCZ serum levels was 5.85 times higher in patients without graft-versus-host disease (GVHD) treatment than in those with GVHD treatment. Four patients on prophylaxis (15%) developed breakthrough IFIs, one of which had a subtherapeutic level. We concluded that the use of PCZ DRT provided adequate concentrations in only 70% of our patients and that recommended dosing may lead to insufficient levels in patients treated for IFIs. Lower concentrations noted among high-risk patients with GVHD suggest a need for prospective studies evaluating therapeutic drug monitoring and/or dose adjustments among these patients.

Infusion-Compatible Antibiotic Formulations for Rapid Administration to Improve Outcomes in Cancer Outpatients With Severe Sepsis and Septic Shock: The Sepsis STAT Pack.

Background: Patients with cancer are at high risk for severe sepsis and septic shock (SS/SSh), and a delay in receiving effective antibiotics is strongly associated with mortality. Delays are due to logistics of clinic flow and drug delivery. In an era of increasing antimicrobial resistance, combination therapy may be superior to monotherapy for patients with SS/SSh. Patients and Methods: At the Seattle Cancer Care Alliance, we implemented the Sepsis STAT Pack (SSP) program to simplify timely and effective provision of empiric antibiotics and other resuscitative care to outpatients with cancer with suspected SS/SSh before hospitalization. Over a 49-month period from January 1, 2008, through January 31, 2012, a total of 162 outpatients with cancer received the intervention. A retrospective cohort study was conducted to determine outcomes, including mortality and adverse events associated with the use of a novel care bundle designed for compatibility of broad-spectrum antibiotics and other supportive care administered concurrently via rapid infusion at fixed doses. Results: Of 162 sequential patients with cancer and suspected SS/SSh who received the SSP, 71 (44%) were diagnosed with SS/SSh. Median age was 53 years and 65% were men; 141 (87%) had hematologic malignancies, 77 (48%) were transplant recipients, and 80 (49%) were neutropenic. Median time to completion of antibiotics was 111 minutes (interquartile range, 60-178 minutes). A total of 71 patients (44%) had bacteremia and 17% of 93 isolates were multidrug-resistant. Possibly related nephrotoxicity occurred in 7 patients, and 30-day mortality occured in 6 of 160 patients (4%), including 3 of 71 (4%) with SS/SSh. Risk of developing SSh or death within 30 days increased 18% (95% CI, 4%-34%) for each hour delay to completion of antibiotics (P=.01). Conclusions: Rapidly administered combination antibiotics and supportive care delivered emergently to ambulatory patients with cancer with suspected SS/SSh was well-tolerated and associated with excellent short-term survival.

Safety and Efficacy of Combination Antiretroviral Therapy in Human Immunodeficiency Virus-Infected Adults Undergoing Autologous or Allogeneic Hematopoietic Cell Transplantation for Hematologic Malignancies.

The ability to continue combination antiretroviral therapy (cART) in human immunodeficiency virus (HIV)-infected patients undergoing hematopoietic cell transplantation (HCT) for treatment of hematologic malignancies is likely a critical factor in preventing the establishment of an HIV reservoir in transplanted stem cells. Thus, we studied the feasibility of continued antiretroviral therapy in our HIV-infected patients undergoing autologous or allogeneic transplantation. All HIV-infected adults undergoing HCT for hematologic malignancy at Fred Hutchinson Cancer Research Center between 2006 and 2014 were included; most were enrolled in a prospective clinical study to monitor HIV reservoirs after transplantation (NCT00968630 and NCT00112593). Non-nucleotide reverse transcriptase inhibitor or integrase-strand inhibitor-anchored antiretroviral therapy regimens were continued or selected before HCT by infectious disease physicians. Plasma HIV RNA was measured every other day for the first 2 weeks after transplantation and then every 2 weeks. Missed doses of cART and reasons for changing the cART regimen during the post-transplantation hospitalization were documented through review of inpatient pharmacy records. Seven autologous and 8 allogeneic transplantations were performed. In 9 transplantations, the cART regimen was not altered after HCT and no doses were missed. In 2 patients who required alterations in their cART regimen because of development of acute renal failure (n = 1) and small bowel obstruction (n = 1) after HCT, enfuvirtide was used as a bridging component of the regimen. Plasma HIV RNA remained suppressed during the first 28 days in 12 of 15 transplantations, and no patients had a plasma HIV RNA >1000 copies/mL during long-term follow up. Non-nucleotide reverse transcriptase inhibitor- and integrase-strand inhibitor-based cART are safe and effective in HIV-infected persons during the peri-HCT period. Most patients undergoing HCT were able to continue cART without missed doses. Sustained HIV viremia and emergence of resistance were not detected.

Impact of rapid influenza PCR testing on hospitalization and antiviral use: A retrospective cohort study.

Rapid PCR-based influenza tests are increasingly used as point-of-care diagnostics in hospitals and clinics. To our knowledge, no prior studies have described clinical outcomes with implementation of rapid PCR-based influenza tests in hospitalized adult inpatients. Electronic medical records were used to assess differences in laboratory testing time and antiviral use among a subset of 175 consecutive adult inpatients tested for influenza in two respiratory seasons before and after implementation of rapid PCR-based influenza testing at an academic medical center. Of the 350 hospitalized inpatients included in this analysis, 96 (27%) were over 65 years of age and 308 (88%) had a comorbid condition. The overall time to result decreased significantly from 25.2 to 1.7 hr (P < 0.001) after implementation of rapid PCR-based influenza testing. Among influenza-negative patients, the frequency of oseltamivir initiation remained unchanged (before: 43% vs. after: 45%; P = 0.60), though the median duration of oseltamivir was significantly decreased from 1.1 to 0.0 days (P < 0.001). By providing an earlier result to clinicians, rapid PCR-based influenza tests may decrease unnecessary antiviral use among adult inpatients who test negative for influenza.

Characterizing Ertapenem Neurotoxicity: A Systematic Review and Experience at a Tertiary Medical Center.

Ertapenem-induced neurotoxicity has not been well characterized and is potentially underreported. We conducted a systematic review of the literature and included 11 additional cases from the University of Washington Medicine health system. A total of 125 individual patient cases were included in the data analysis. The mean age was 72 years, and 62% and 42% of patients had renal dysfunction and preexisting central nervous system (CNS) conditions, respectively. Only 15% of patients received inappropriately high ertapenem dosing based on kidney function. Patients developed neurological signs and symptoms after a median of 4 days (interquartile range, 3-9 days). The most common clinical features were seizures (70%), altered level of consciousness or delirium (27%), and hallucinations (17%). An estimated incidence in our health system was 1 in 102 courses of ertapenem. Ertapenem neurotoxicity should be suspected when a patient with renal dysfunction or predisposing CNS conditions develops neurological signs and symptoms, especially within several days after initiating the antibiotic. This study underscores the need for a large prospective study to assess the true incidence and outcomes of ertapenem neurotoxicity.

Asymptomatic bacteriuria in critical-access hospitals: Prevalence and patient characteristics driving treatment.

We evaluated the prevalence and treatment of asymptomatic bacteriuria (ASB) in 17 critical-access hospitals. Among 891 patients with urine cultures from September 2021 to June 2022, 170 (35%) had ASB. Also, 76% of patients with ASB received antibiotics for a median duration of 7 days, demonstrating opportunities for antimicrobial stewardship.

Diagnostic testing and antibiotic utilization among inpatients evaluated for coronavirus disease 2019 (COVID-19) pneumonia.

We evaluated diagnostic test and antibiotic utilization among 252 patients from 11 US hospitals who were evaluated for coronavirus disease 2019 (COVID-19) pneumonia during the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) omicron variant pandemic wave. In our cohort, antibiotic use remained high (62%) among SARS-CoV-2-positive patients and even higher among those who underwent procalcitonin testing (68%).

Voriconazole therapeutic drug monitoring: retrospective cohort study of the relationship to clinical outcomes and adverse events.

BACKGROUND: Voriconazole is approved for treatment of invasive aspergillosis and other invasive fungal infections, but the role for therapeutic drug monitoring (TDM) is not clear. METHODS: We performed a retrospective cohort study of patients at the University of Washington Medical Center and Fred Hutchinson Cancer Research Center from 2007-2009. We compared the effect of therapeutic levels on clinical outcomes and evaluated the relationship between drug levels and adverse events. RESULTS: A total of 108 patients had voriconazole TDM performed, of whom 84 (77.8%) had a hematologic malignancy and 47 (43.5%) had undergone hematopoietic stem cell transplantation. The primary reasons for treatment were presumed pulmonary aspergillosis (n = 83, 76.8%), other invasive mould infections (n = 13, 12.0%) and candidiasis (n = 9, 8.3%). There was a high degree of variability in voriconazole drug levels among patients (r2 = 0.01; range, <0.10 - 20 mg/L). Of the 46 patients with proven or probable invasive fungal disease, 25 (54.3%) achieved partial or complete response to therapy. There was no significant relationship between therapeutic drug levels and achievement of complete or partial response at 12 weeks (OR 0.29, 95% CI: 0.05-1.34) or radiologic response (OR 1.46, 95% CI: 0.32-7.83). Overall, 45 (41.7%) patients experienced adverse events. Voriconazole levels > 5.5 mg/L were not associated with increased incidence of encephalopathy (OR 3.08, 95% CI 0.79-11.0) or hepatotoxicity (OR 2.45, 95% CI 0.49-10.1). CONCLUSIONS: Voriconazole therapeutic drug levels were not associated with improvement in clinical outcomes among patients with proven or probable invasive fungal disease. We also did not find an association between supratherapeutic drug levels and hepatoxicity or encephalopathy. It is possible that the utility of voriconazole therapeutic drug monitoring to improve clinical efficacy or decrease adverse events may be limited to a subset of high-risk patients.