Rechallenge With High-Dose Methotrexate After Treatment With Glucarpidase in Adult Patients With Lymphoma

PURPOSE

Limited evidence exists regarding methotrexate (MTX) resumption after patients with lymphoma receive glucarpidase for toxic MTX levels and acute kidney injury (AKI).

METHODS

This retrospective review included adults with lymphoma treated with glucarpidase after MTX at Mayo Clinic between January 31, 2020, and October 10, 2022. Descriptive statistics summarize patient characteristics and clinical outcomes.

RESULTS

Of 11 patients treated with glucarpidase after MTX, seven (64%) were rechallenged with MTX. Indications for MTX rechallenge included confirmed CNS disease (n = 6, 86%) and intravascular lymphoma (n = 1, 14%). Compared with the nonrechallenged subgroup, before receiving MTX that required glucarpidase rescue, the rechallenged patients had lower median pretreatment serum creatinine (Scr; 0.7 v 1.2 mg/dL), and none had AKI with previous MTX doses, n = 0 (0%) versus n = 2 (50%). During the MTX dose requiring glucarpidase rescue, the rechallenged group had lower median peak Scr (1.26 v 3.32 mg/dL) and lower incidence of AKI stage III (n = 1 [14%] v n = 3 [75%]), and none of the rechallenged patients required renal replacement therapy (RRT; n = 0 [0%] v n = 1 [25%]). At the first rechallenge after glucarpidase administration, the median MTX dose reduction was 56% (range, 46%-75%), and the lowest used dose when prescribed according to each treatment protocol schedule was 1.5 g/m2. Two (29%) patients experienced AKI (n = 1 stage I, n = 1 stage II) after MTX rechallenge. Zero patients required RRT, and zero required another glucarpidase administration. Six (86%) patients completed all recommended MTX doses.

CONCLUSION

In selected adults with lymphoma who required glucarpidase for toxic MTX levels after administration of high-dose MTX, resumption of MTX therapy at lower doses is safe. Patients selected for MTX resumption had experienced less severe AKI during the previous cycle compared with those not selected for MTX resumption.

Development and validation of a model to predict acute kidney injury following high-dose methotrexate in patients with lymphoma

STUDY OBJECTIVE

To develop and validate a model for predicting acute kidney injury (AKI) after high-dose methotrexate (HDMTX) exposure.

DESIGN

Retrospective analysis.

SETTING

Multisite integrated health system throughout Minnesota and Wisconsin.

PATIENTS

Adult patients with lymphoma who received HDMTX as a 4-h infusion.

MEASUREMENTS AND MAIN RESULTS

LASSO methodology was used to identify factors available at the outset of therapy that predicted incident AKI within 7 days following HDMTX. The model was then validated in an independent cohort. The incidence of AKI within 7 days following HDMTX was 21.6% (95% confidence interval (CI) 18.4%-24.8%) in the derivation cohort (435 unique patients who received a total of 1642 doses of HDMTX) and 15.6% (95% CI 5.3%-24.8%) in the validation cohort (55 unique patients who received a total of 247 doses of HDMTX). Factors significantly associated with AKI after HDMTX in the multivariable model included age ≥ 55 years, male sex, and lower HDMTX dose number. Other factors that were not found to be significantly associated with AKI on multivariable analysis, but were included in the final model, were body surface area, Charlson Comorbidity Index, and estimated glomerular filtration rate. The c-statistic of the model was 0.72 (95% CI 0.69-0.75) in the derivation cohort and 0.72 (95% CI 0.60-0.84) in the validation cohort.

CONCLUSION

This model utilizing identified sociodemographic and clinical factors is predictive of AKI following HDMTX administration in adult patients with lymphoma.

Tissue Inhibitor Metalloproteinase-2 and Insulin-Like Growth Factor Binding Protein-7 Kinetics Following Exposure to High-Dose Methotrexate

Urinary TIMP2×IGFBP7 (uTIMP2×IGFBP7) concentrations experienced a rapid and sustained decline after high-dose methotrexate (MTX) exposure. uTIMP2×IGFBP7 kinetics and concentrations after high-dose MTX exposure demonstrated no utility in predicting AKI.

Procalcitonin as a biomarker for predicting bacterial infection in chimeric antigen receptor T-cell therapy recipients

BACKGROUND

It is unknown whether serum procalcitonin (PCT) concentration monitoring can differentiate between bacterial infection or cytokine release syndrome (CRS) when chimeric antigen receptor T-cell (CAR-T) recipients present with a constellation of signs and symptoms that may represent both complications.

OBJECTIVE

The objective of the study was to assess the utility of serum PCT concentrations as a biomarker of bacterial infection in CAR-T recipients.

STUDY DESIGN

This single-center, retrospective, medical record review evaluated patients prescribed CAR-T therapy until death or 30 days after infusion. Logistic regression modeling determined the association between elevated serum PCT concentrations within 48 h of fever onset and microbiologically confirmed infection. Secondary outcomes included clinically suspected infection, CAR-T toxicity rates, and broad-spectrum antibiotic usage. Predictive performance of PCT was assessed by area under the receiver operating characteristic curve (AUC).

RESULTS

The 98 included patients were a median age of 63 (IQR: 55-69) years old, 47 (48%) were male, and 87 (89%) were Caucasian. Baseline demographics and clinical characteristics were similar between patients with and without a bacterial infection. Serum PCT >0.4 ng/mL within 48 h of fever was significantly associated with a microbiologically confirmed bacterial infection (OR: 2.75 [95% CI: 1.02-7.39], p = 0.045). Median PCT values in patients with and without confirmed infections were 0.40 ng/mL (IQR: 0.26, 0.74) and 0.26 ng/mL (IQR: 0.13, 0.47), respectively. The AUC for PCT to predict bacterial infection was 0.62 (95% CI 0.48-0.76). All patients experienced CRS of some grade, with no difference in CRS severity based on elevated PCT. Broad-spectrum antibiotics were used for a median of 45% and 23% of days in those with and without confirmed infection, respectively (p = 0.075).

CONCLUSION

Elevated serum PCT concentrations above 0.4 ng/mL at time of first fever after CAR-T infusion was significantly associated with confirmed bacterial infection. Furthermore, rigorous, prospective studies should validate our findings and evaluate serial PCT measurements to optimize antimicrobial use after CAR-T therapy.

Insights from a pharmacometric analysis of HDMTX in adults with cancer: Clinically relevant covariates for application in precision dosing

AIMS

High-dose methotrexate (HDMTX) is an essential part of the treatment of several adult and paediatric malignancies. Despite meticulous supportive care during HDMTX administration, severe toxicities, including acute kidney injury (AKI), may occur contributing to patient morbidity. Population pharmacokinetics provide a powerful tool to predict time to clear HDMTX and adjust subsequent doses. We sought to develop and validate pharmacokinetic models for HDMTX in adults with diverse malignancies and to relate systemic exposure with the occurrence of severe toxicity.

METHODS

Anonymized, de-identified data were provided from 101 US oncology practices that participate in the Guardian Research Network, a non-profit clinical research consortium. Modelled variables included clinical, laboratory, demographic and pharmacological data. Population pharmacokinetic analysis was performed by means of nonlinear mixed effects modelling using MonolixSuite.

RESULTS

A total of 693 HDMTX courses from 243 adults were analysed, of which 62 courses (8.8%) were associated with stage 2/3 acute kidney injury (43 stage 2, 19 stage 3). A three-compartment model adequately fitted the data. Time-dependent serum creatinine, baseline serum albumin and allometrically scaled bodyweight were clinically significant covariates related to methotrexate clearance. External evaluation confirmed a satisfactory predictive performance of the model in adults receiving HDMTX. Dose-normalized methotrexate concentration at 24 and 48 hours correlated with AKI incidence.

CONCLUSION

We developed a population pharmacometric model that considers weight, albumin and time-dependent creatinine that can be used to guide supportive care in adult patients with delayed HDMTX elimination.

Variation in Clinical Practice and Attitudes on Antibacterial Management of Fever and Neutropenia in Patients With Hematologic Malignancy: A Survey of Cancer Centers Across the United States

Background

Contemporary information regarding fever and neutropenia (FN) management, including approaches to antibacterial prophylaxis, empiric therapy, and de-escalation across US cancer centers, is lacking.

Methods

This was a self-administered, electronic, cross-sectional survey of antimicrobial stewardship physicians and pharmacists at US cancer centers. The survey ascertained institutional practices and individual attitudes on FN management in high-risk cancer patients. A 5-point Likert scale assessed individual attitudes.

Results

Providers from 31 of 86 hospitals (36%) responded, and FN management guidelines existed in most (29/31, 94%) hospitals. Antibacterial prophylaxis was recommended in 27/31 (87%) hospitals, with levofloxacin as the preferred agent (23/27, 85%). Cefepime was the most recommended agent for empiric FN treatment (26/29, 90%). Most institutional guidelines (26/29, 90%) recommended against routine addition of empiric gram-positive agents except for specific scenarios. Eighteen of 29 (62%) hospitals explicitly provided guidance on de-escalation of empiric, systemic antibacterial therapy; however, timing of de-escalation was variable according to clinical scenario. Among 34 individual respondents, a majority agreed with use of antibiotic prophylaxis in high-risk patients (25, 74%). Interestingly, only 10 (29%) respondents indicated agreement with the statement that benefits of antibiotic prophylaxis outweigh potential harms.

Conclusion

Most US cancer centers surveyed had institutional FN management guidelines. Antibiotic de-escalation guidance was lacking in nearly 40% of centers, with heterogeneity in approaches when recommendations existed. Further research is needed to inform FN guidelines on antibacterial prophylaxis and therapy de-escalation.

Prospective evaluation of high-dose methotrexate pharmacokinetics in adult patients with lymphoma using novel determinants of kidney function

High-dose methotrexate (HDMTX) pharmacokinetics (PKs), including the best estimated glomerular filtration rate (eGFR) equation that reflects methotrexate (MTX) clearance, requires investigation. This prospective, observational, single-center study evaluated adult patients with lymphoma treated with HDMTX. Samples were collected at predefined time points up to 96 h postinfusion. MTX and 7-hydroxy-MTX PKs were estimated by standard noncompartmental analysis. Linear regression determined which serum creatinine- or cystatin C-based eGFR equation best predicted MTX clearance. The 80 included patients had a median (interquartile range [IQR]) age of 68.6 years (IQR 59.2-75.6), 54 (67.5%) were men, and 74 (92.5%) were White. The median (IQR) dose of MTX was 7.6 (IQR 4.8-11.3) grams. Median clearance was similar across three dosing levels at 4.5-5.6 L/h and was consistent with linear PKs. Liver function, weight, age, sex, concomitant chemotherapy, and number of previous MTX doses did not impact clearance. MTX area under the curve (AUC) values varied over a fourfold range and appeared to increase in proportion to the dose. The eGFR_cys (ml/min) equation most closely correlated with MTX clearance in both the entire cohort and after excluding outlier MTX clearance values (r = 0.31 and 0.51, respectively). HDMTX as a 4-h infusion displays high interpatient pharmacokinetic variability. Population PK modeling to optimize MTX AUC attainment requires further evaluation. The cystatin C-based eGFR equation most closely estimated MTX clearance and should be investigated for dosing and monitoring in adults requiring MTX as part of lymphoma management.

Incidence of Pneumocystis jirovecii pneumonia utilizing a polymerase chain reaction-based diagnosis in patients receiving bendamustine

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening infection occurring in patients receiving bendamustine. The poorly defined incidence, particularly when utilizing polymerase chain reaction (PCR)-based diagnostic techniques, precipitates unclear prophylaxis recommendations. Our objective was to determine the cumulative incidence of PJP diagnosed by single copy target, non-nested PCR in patients receiving bendamustine.

METHODS

Patients were evaluated for PJP from initiation of bendamustine through 9 months after the last administration. The cumulative incidence of PJP was estimated using the Aalen-Johansen method. Cox proportional hazard models were used to demonstrate the strength of association between the independent variables and PJP risk.

RESULTS

This single-center, retrospective cohort included 486 adult patients receiving bendamustine from 1 January 2006 through 1 August 2019. Most patients received bendamustine-based combination therapy (n = 461, 94.9%), and 225 (46.3%) patients completed six cycles. Rituximab was the most common concurrent agent (n = 431, 88.7%). The cumulative incidence of PJP was 1.7% (95% CI 0.8%-3.3%, at maximum follow-up of 2.5 years), after the start of bendamustine (n = 8 PJP events overall). Prior stem cell transplant, prior chemotherapy within 1 year of bendamustine, and lack of concurrent chemotherapy were associated with the development of PJP in univariate analyses. Anti-Pneumocystis prophylaxis was not significantly associated with a reduction in PJP compared to no prophylaxis (HR 0.37, 95% CI (0.05, 3.04), p = 0.36).

CONCLUSIONS

Our incidence of PJP below 3.5%, the conventional threshold for prophylaxis implementation, indicates routine anti-Pneumocystis prophylaxis may not be necessary in this population. Factors indicating a high-risk population for targeted prophylaxis require further investigation.

Lack of drug interaction between levetiracetam and high-dose methotrexate in patients with lymphoma

STUDY OBJECTIVE

To determine whether there is a drug-drug interaction precluding the concomitant use of levetiracetam and high-dose methotrexate (HDMTX).

DESIGN

Retrospective analysis.

SETTING

Large academic tertiary care medical center.

PATIENTS

Adult lymphoma patients who received HDMTX as a 4-h infusion with or without concomitant levetiracetam.

MEASUREMENTS AND MAIN RESULTS

Generalized estimating equations clustered on patient were used to assess each outcome. The primary outcome was the incidence of delayed MTX elimination (MTX level >1 µmol/L at 48 h). Secondary outcomes included incidence of acute kidney injury (AKI) and hospital length of stay (LOS). The 430 included patients receiving 1993 doses of HDMTX had a median (IQR) age of 66 (57.5, 72.6) years, 88 (20.5%) received concomitant levetiracetam with at least one dose of MTX, 267 (62.1%) were male, and 397 (92.3%) were Caucasian. HDMTX doses ranged from 1 to 8 g/m² . The most common lymphoma diagnoses were systemic diffuse large B-cell lymphoma (DLBCL; 58.5%) and systemic DLBCL with central nervous system (CNS) involvement (32.8%). Rates of delayed elimination with and without levetiracetam were 13.4% and 16.3%, respectively (OR = 0.80, 95% CI 0.47-1.34, p = 0.39). AKI occurred in 15.6% and 17.0% of patients with and without concomitant levetiracetam, respectively (OR = 0.83, 95% CI 0.52-1.33, p = 0.28). The median LOS with and without levetiracetam was 4.2 and 4.1 days, respectively (p = 0.039). On multivariable analyses, only age, body surface area, diagnosis of systemic DLBCL with CNS involvement, serum creatinine, hemoglobin, total bilirubin, and dose of HDMTX were associated with delayed elimination.

CONCLUSIONS

High-dose methotrexate administered with concomitant levetiracetam was not associated with increased risk for delayed MTX elimination or AKI. These results support that levetiracetam and HDMTX are safe for coadministration.

Early, empiric high-dose leucovorin rescue in lymphoma patients treated with sequential doses of high-dose methotrexate

BACKGROUND

In patients exposed to high-dose methotrexate (HDMTX; >1g/m²) with a history of elevated methotrexate (MTX) concentrations during previous doses, it is unclear whether prescribing high-dose leucovorin (HDLV) rescue limits future high levels or reduces the likelihood of acute kidney injury (AKI).

METHODS

This retrospective, single-center study longitudinally followed adult lymphoma patients treated with HDMTX between 1/1/2011 and 10/31/2017 from diagnosis until 30 days after the last HDMTX dose. Endpoints included elevated MTX concentrations at 48 h (>1.0 μmol/L) and incident AKI after each HDMTX dose.

RESULTS

The 321 included patients had a median (IQR) age of 65 (57, 72) years, 190 (59%) were male, and 293 (91%) were Caucasian. There were 1558 HDMTX doses [median (IQR) 3 (2, 6) doses per patient] prescribed with 265 (83%) patients receiving more than one MTX dose. Those receiving HDLV rescue were more likely to have an elevated MTX concentration after that dose (OR = 2.69, 95% CI: 1.75-4.11, p < 0.001). Receiving HDLV rescue was associated with a greater likelihood of AKI after MTX (OR = 2.18, 95% CI: 1.38-3.43, p < 0.001). Hospital LOS was longer in those prescribed empiric HDLV rescue after MTX than those prescribed standard leucovorin with an estimated difference of 1.1 days, (95% CI: 0.5-1.7, p < 0.001).

CONCLUSION

Sequential HDMTX doses are associated with a significant incidence of elevated MTX levels and AKI during lymphoma management. HDLV rescue prescribed during subsequent MTX doses in patients with a previously elevated level was not associated with improved safety outcomes. The optimal supportive care strategy following HDMTX administration requires further investigation.

208. Variation in Clinical Practice and Attitudes in the Management of Fever and Neutropenia in Patients With Hematologic Malignancy: A Survey of Cancer Centers Across the United States

Background

Fever and neutropenia (FN) is common in cancer patients after chemotherapy, and there are national guideline recommendations for FN prevention and treatment. We conducted a survey of practices across multiple US cancer centers to determine the extent to which these guidelines have been adapted.

Methods

US cancer centers performing 20 allogeneic hematopoietic stem cell transplantations annually were identified from the National Marrow Donor Program’s “Be the Match” directory. Antimicrobial stewardship physicians and pharmacists at each institution were identified using institutional websites, residency or fellowship program directories, and personal contacts. A survey assessing institutional practices and individual attitudes on FN management in high-risk patients was distributed via email. Duplicate responses at the hospital level were removed. Complete surveys regarding individual attitudes were assessed using a 5-point Likert scale ranging from “Strongly Agree” to “Strongly Disagree.”

Results

Thirty-four (23%) responses from 148 individuals were received, representing 31 of 86 hospitals (36%). 29 (94%) hospitals reported having guidelines for the management of FN. Of these, cefepime was the most commonly recommended agent for empiric treatment (26, 90%) and 16 (55%) provide guidance based on presumed site of infection. Eighteen (62%) hospitals recommend de-escalation of Gram negative therapy in certain situations, most often after being afebrile 48 – 72 hours or after neutrophil recovery (7 each, 39%). Twenty-seven (93%) hospitals recommended antibiotic prophylaxis, most often with levofloxacin (21, 78%). Of 34 respondents, attitudes were split regarding the statement “The benefit of antibiotic prophylaxis outweighs the harms in high-risk patients” (10 strongly agree or agree, 10 strongly disagree or disagree; 29% each); most agreed with the statement “I would use antibiotic prophylaxis in high-risk patients” (25, 78%).

Conclusion

Most cancer centers across the US have guidelines for the management of FN. While most recommend antibacterial prophylaxis, there were differences in individual perceptions regarding the risk / benefit. Significant variation exists in the approach to antibiotic de-escalation.

Disclosures

All Authors: No reported disclosures

Incidence, clinical presentation, and outcomes of Pneumocystis pneumonia when utilizing Polymerase Chain Reaction-based diagnosis in patients with Hodgkin lymphoma

A Polymerase Chain Reaction-based diagnosis of Pneumocystis Pneumonia (PCP) and the need for anti-Pneumocystis prophylaxis in Hodgkin lymphoma patients receiving chemotherapy requires further investigation. This retrospective, single-center, study evaluated 506 consecutive adult patients diagnosed with Hodgkin lymphoma receiving chemotherapy between January 2006 and August 2018. The cumulative incidence of PCP 1 year after start of chemotherapy was 6.2% (95% CI 3.8-8.5%). Mortality 30 days from PCP diagnosis was 8% (n = 2) with one death attributable to PCP. Bleomycin-containing combination chemotherapy regimen was not significantly associated with a higher risk for PCP when compared to other regimens (HR = 1.59, 95% CI 0.55-4.62 p = 0.40). Anti-Pneumocystis prophylaxis was not significantly associated with a decreased incidence of PCP (HR = 0.51, 95% CI 0.15-1.71, p = 0.28). As the overall incidence is above the commonly accepted 3.5% threshold, clinicians should consider the potential value of prophylaxis. The utility of universal vs. targeted anti-Pneumocystis prophylaxis requires prospective, randomized investigation.

Cystatin C: A Primer for Pharmacists

Pharmacists are at the forefront of dosing and monitoring medications eliminated by or toxic to the kidney. To evaluate the effectiveness and safety of these medications, accurate measurement of kidney function is paramount. The mainstay of kidney assessment for drug dosing and monitoring is serum creatinine (SCr)-based estimation equations. Yet, SCr has known limitations including its insensitivity to underlying changes in kidney function and the numerous non-kidney factors that are incompletely accounted for in equations to estimate glomerular filtration rate (eGFR). Serum cystatin C (cysC) is a biomarker that can serve as an adjunct or alternative to SCr to evaluate kidney function for drug dosing. Pharmacists must be educated about the strengths and limitations of cysC prior to applying it to medication management. Not all patient populations have been studied and some evaluations demonstrated large variations in the relationship between cysC and GFR. Use of eGFR equations incorporating cysC should be reserved for drug management in scenarios with demonstrated outcomes, including to improve pharmacodynamic target attainment for antibiotics or reduce drug toxicity. This article provides an overview of cysC, discusses evidence around its use in medication dosing and in special populations, and describes practical considerations for application and implementation.

Effect of a multimodal multidisciplinary training program on pharmacy residents' knowledge and confidence toward research and biostatistics

INTRODUCTION

The optimal method to increase pharmacy resident knowledge and confidence toward research remains unknown.

OBJECTIVE

This study evaluated the impact of a structured curriculum on pharmacy residents' knowledge, confidence and attitude toward biostatistics and research.

METHODS

This prospective, multicenter study included pharmacy residents from 2016 to 2017. Residents underwent research training with (1) 60-hours of online modules delivered by multidisciplinary senior faculty (MD, PhD), (2) a 2-day interactive workshop delivered by experienced pharmacy researchers and (3) a mentored longitudinal research experience. Fifteen residents were invited to complete a questionnaire at baseline and again before graduation to measure knowledge, confidence and attitudes about research. Residents were followed for one additional year to measure peer-reviewed publications.

RESULTS

Eleven (73%) residents provided complete responses to ≥1survey domain. At baseline, 27% of respondents reported being at least somewhat confident about their biostatistics and research skills (a favorable response for ≥5 of the 9 confidence items). At follow-up, 91% self-reported confidence. Self-reported familiarity with statistical terminology (a score of 4 or 5) increased from 19% at baseline to 82% at follow-up. The mean correct score on the knowledge items at baseline was 15 ± 2.5 (total possible 28) and increased to 20 ± 2.7 after training. By one year after graduation, 53% of residents published at least 1 peer-reviewed manuscript and 20 peer-reviewed publications as first or co-author with a median journal impact factor of 3.16 (IQR: 2.61-4.59).

CONCLUSION

This study provides a framework for sustainable, multidisciplinary, multimodal research education that increased confidence and knowledge among pharmacy residents and resulted in tangible contributions to the scientific literature. Future studies should explore long-term knowledge gained and publications.

QT prolongation in patients with acute leukemia or high-risk myelodysplastic syndrome prescribed antifungal prophylaxis during chemotherapy-induced neutropenia

Benefits of serial electrocardiographic (ECG) monitoring to detect QT prolongation in patients with hematological malignancies remain unclear. This retrospective, single-center, study evaluated 316 adult acute leukemia and high-risk MDS patients who received 11,775 patient-days of voriconazole prophylaxis during induction chemotherapy. Of these, 37 patients (16.2%) experienced QTc prolongation. Medications associated with QTc prolongation included furosemide, haloperidol, metronidazole, mirtazapine, prochlorperazine, and venlafaxine. Hypokalemia and hypomagnesemia were also significantly associated with QTc prolongation (HR 3.15; p = .003 and HR 6.47, p = .007, respectively). Management modifications due to QTc prolongation included discontinuation of QT prolonging medications (n = 25), more aggressive electrolyte repletion (n = 5), and enhanced ECG monitoring (n = 3). One patient with multiple QT prolonging factors experienced possible Torsades de Pointes. Overall mortality was 15% with no cardiac-related deaths. Serial ECG monitoring during induction chemotherapy can be tailored proportionally to QT-prolonging risk factors. Management should include aggressive electrolyte repletion and avoidance of concurrent QT prolonging medications.

Preadmission Corticosteroid Therapy and the Risk of Respiratory Failure in Adults Without HIV Presenting With Pneumocystis Pneumonia

BACKGROUND

Corticosteroid therapy is a well-recognized risk factor for Pneumocystis pneumonia (PCP); however, it has also been proposed as an adjunct to decrease inflammation and respiratory failure.

OBJECTIVE

To determine the association between preadmission corticosteroid use and risk of moderate-to-severe respiratory failure at the time of PCP presentation.

METHODS

This retrospective cohort study evaluated HIV-negative immunosuppressed adults diagnosed with PCP at Mayo Clinic from 2006 to 2016. Multivariable regression models were used to evaluate the association between preadmission corticosteroid exposure and moderate-to-severe respiratory failure at presentation.

RESULTS

Of the 323 patients included, 174 (54%) used preadmission corticosteroids with a median daily dosage of 20 (interquartile range: 10-40) mg of prednisone or equivalent. After adjustment for baseline demographics, preadmission corticosteroid therapy did not decrease respiratory failure at the time of PCP presentation (odds ratio: 1.23, 95% confidence interval: 0.73-2.09, P = .38). Additionally, after adjusting for inpatient corticosteroid administration, preadmission corticosteroid use did not impact the need for intensive care unit admission (P = .98), mechanical ventilation (P = .92), or 30-day mortality (P = .11).

CONCLUSIONS

Corticosteroid exposure before PCP presentation in immunosuppressed HIV-negative adults was not associated with a reduced risk of moderate-to-severe respiratory failure.

A comparison of levofloxacin and oral third-generation cephalosporins as antibacterial prophylaxis in acute leukaemia patients during chemotherapy-induced neutropenia

Background

There is demonstrated benefit with fluoroquinolones as infection prophylaxis in neutropenic patients; however, side effects, drug interactions and increasing resistance necessitate investigation of alternative therapies.

Objectives

To compare the incidence of febrile neutropenia in high-risk patients with haematological malignancy receiving a fluoroquinolone with those receiving an oral third-generation cephalosporin (OTGC) as antibacterial prophylaxis during chemotherapy-induced neutropenia.

Methods

A retrospective, matched, single-centre study comparing clinical and microbiological outcomes in acute leukaemia patients receiving fluoroquinolones versus OTGCs as antibacterial prophylaxis after chemotherapy.

Results

A total of 120 patients (levofloxacin n = 80, OTGC n = 40) were included and matched. The 30 day incidence of febrile neutropenia was 89.7% (95% CI = 82.4-93.9). The rates of febrile neutropenia were similar between antimicrobials (OTGC versus levofloxacin HR = 0.90, 95% CI = 0.54-1.52, P = 0.70). The most frequent site of infection was the bloodstream (line related) (n = 24, 62%) and the majority (n = 28, 72%) of infections were caused by Gram-positive organisms. Groups were similar in terms of site of infection (P = 0.91) and morphology of recovered microorganisms (P = 0.74). There were significantly more cultures positive for Enterobacter spp. in the OTGC group (P = 0.043). Three patients died during follow-up (from first dose up to 30 days after the last dose) (30 day survival = 99.2%, 95% CI = 97.5-100), with only two of the reported deaths attributable to infection.

Conclusions

These findings demonstrate comparable rates of febrile neutropenia and culture positivity with an increase in cultures positive for Enterobacter spp. when OTGCs are compared with levofloxacin for antibacterial prophylaxis during chemotherapy-induced neutropenia. Further prospective, randomized investigation is warranted.

Safety and feasibility of lower antithrombin replacement targets in adult patients with hematological malignancies receiving asparaginase therapy<sup/>

The optimal antithrombin(AT) activity parameters for replacement as thromboprophylaxis following asparaginase remains unclear. This single-center, retrospective study evaluated two sets of AT replacement thresholds and targets in adults receiving asparaginase-containing chemotherapy. AT supplementation adhered to institutional standards, which lowered the AT activity target from 100% to 80% in 6/2014. Ninety-two patients were evaluated. Cumulative thrombosis incidence was 16% at 6 months (95%CI:6.8-24.0, maximum follow-up 315 days) with similar incidence between the 80% and 100% target groups, 14% (2 of the 14) and 13% (10 of the 78), respectively, with a small non-Line-Related DVT incidence (3%). Most thrombotic events occurred during induction chemotherapy and demonstrated no associations with replacement target, cumulative days or cumulative area under AT activity target, number of asparaginase doses, or cumulative asparaginase dose. Median estimated AT replacement expenditure was $34,963USD (IQR $16,260USD to $79,319USD) per patient. Cost-effectiveness and optimization of AT replacement for thromboprophylaxis following asparaginase requires prospective evaluation.

Cystatin C-Guided Vancomycin Dosing in Critically Ill Patients: A Quality Improvement Project

BACKGROUND

The aim of the study was to determine whether a vancomycin dosing algorithm based on estimated glomerular filtration rate from creatinine and cystatin C levels (eGFR_cr-cys) improves target trough concentration achievement compared to an algorithm based on estimated creatinine clearance (eCL_cr) in critically ill patients.

STUDY DESIGN

This prospective quality improvement project evaluated intensive care unit (ICU) patients started on intravenous vancomycin using one of 2 different strategies. Dosing regimens were selected and implemented after an individualized goal trough range was established (10-15 or 15-20mg/L). Steady-state goal trough achievement was compared between treatment arms with and without adjustment for potential confounders.

SETTING & PARTICIPANTS

3 medical and surgical ICUs at a single tertiary medical center.

QUALITY IMPROVEMENT PLAN

During January 2012 to October 2013, vancomycin was dosed according to eCL_cr using the Cockcroft-Gault formula (control arm). During December 2013 to May 2015, a multidisciplinary quality improvement team implemented a novel vancomycin dosing algorithm according to eGFR_cr-cys using the CKD-EPI equation (intervention arm).

OUTCOME

Steady-state initial goal vancomycin trough concentration achievement.

MEASUREMENTS & RESULTS

More patients in the intervention arm (67 of 135 [50%]) achieved therapeutic trough vancomycin levels than in the control arm (74 of 264 [28%]; OR, 2.53; 95% CI, 1.65-3.90; P<0.001). Improved trough achievement was maintained even after adjustment for age, sex, APACHE (Acute Physiology and Chronic Health Evaluation) III score, fluid balance, baseline CL_cr, surgical admission diagnosis, presence of sepsis, and goal trough concentration range (adjusted OR, 2.79; 95% CI, 1.76-4.44; P<0.001). Clinical outcomes were similar between groups.

LIMITATIONS

Nonrandomized, incomplete algorithm compliance.

CONCLUSIONS

A vancomycin dosing nomogram based on eGFR_cr-cys significantly improved goal trough achievement compared to eCL_cr among ICU patients with stable kidney function. Further studies are warranted to characterize the relationship between use of cystatin C-guided dosing and clinical outcomes.

Characterization of Admission Types in Medically Hospitalized Patients Prescribed Clozapine

BACKGROUND

Clozapine is the antipsychotic of choice for treatment-resistant schizophrenia; however, rigorous monitoring is required to prevent or detect adverse drug events that contribute to morbidity and mortality. In addition to the Food and Drug Administration (FDA) boxed safety warnings specific to clozapine (agranulocytosis, hypotension, seizures, and cardiomyopathy/myocarditis), other adverse events such as pneumonia and gastrointestinal hypomotility have been reported in the literature to result in hospitalization.

OBJECTIVE

To explore the reasons for medical hospitalization in patients prescribed clozapine, a retrospective chart review was completed.

METHODS

Adults with schizophrenia or schizoaffective disorder prescribed clozapine were identified if they had a nonpsychiatric medical admission between 1/1/2003 and 8/1/2015. Demographics, admitting diagnosis, admitting service type, psychiatric consult information, clozapine dosing, and drug interactions were collected.

RESULTS

Overall, 104 patients, representing 248 hospitalizations, were admitted to a medical unit during the study period. The predominant admission types were for the management of either pulmonary (32.2%) or gastrointestinal (19.8%) illnesses. The most common pulmonary diagnosis was pneumonia, accounting for 58% of pulmonary admissions. Further, 61.2% of the gastrointestinal admissions were related to hypomotility, ranging from constipation to death. Clozapine was discontinued owing to neutropenia in 2 patients; however, in both cases concomitant chemotherapy had been given.

CONCLUSION

In patients prescribed clozapine admitted to nonpsychiatric medical settings, gastrointestinal and pulmonary illnesses were common, but not illnesses related to boxed warnings. Additional research is needed to better assess the causality and true incidence of gastrointestinal or pulmonary events associated with clozapine. Furthermore, clinicians must be prepared to prevent, detect, and manage potentially life-threatening events associated with clozapine.

Low incidence of pneumocystis pneumonia utilizing PCR-based diagnosis in patients with B-cell lymphoma receiving rituximab-containing combination chemotherapy

Recent literature has demonstrated concern over the risk of Pneumocystis jirovecii pneumonia (PJP) when administering rituximab with combination chemotherapy such as in R-CHOP; however, the exact risk and potential need for prophylaxis is unknown. We sought to determine the incidence of PJP infection following R-CHOP administration in patients with B-cell lymphoma. Consecutive patients diagnosed with B-cell lymphoma receiving R-CHOP were evaluated from chemotherapy initiation until 180 days after the last administration. The primary outcome was cumulative incidence of PJP infection. Secondary endpoints included the association of rituximab, prednisone and subsequent chemotherapy with PJP infection risk. A total of 689 patients (53% male, median age 66 years) were included. Seventy-three percent of patients completed at least 6 cycles of R-CHOP treatment. Median rituximab and prednisone cumulative doses were 3950 mg and 5325 mg, respectively. Median daily prednisone dose through end of treatment was 45 mg (range 7.6 mg to 119 mg). The cumulative incidence of PJP was 1.51% (95% CI 0.57-2.43, at maximum follow-up of 330 days), below 3.5%, the conventional threshold for prophylaxis. Univariate analysis did not detect a statistically significant association between PJP and rituximab, steroids, or receipt of additional chemotherapy in this patient population. Our results demonstrate a low occurrence of Pneumocystis pneumonia during R-CHOP treatment of B-cell lymphoma and argue against universal anti-Pneumocystis prophylaxis in this setting. Further investigations should focus on targeted anti-Pneumocystis prophylaxis for patients presenting with high-risk baseline characteristics or when receiving rituximab-inclusive intensive combination chemotherapy regimens as treatment for other aggressive lymphoma subtypes. Am. J. Hematol. 91:1113-1117, 2016. © 2016 Wiley Periodicals, Inc.

Influenza infection in neutropenic adults

While lymphopenia is a well-defined risk factor for severe influenza, the effect of neutropenia is unknown. This was a retrospective single centre study of adult patients with documented neutropenia and influenza between 2005 and 2013. Forty patients were included with a median follow-up of 2 years (IQR 0.8-4.0). Median ANC at influenza diagnosis was 0.3 × 10⁹/L (IQR 0.1-0.4 × 10⁹/L). Outcomes included hospitalization (N = 28, 70%), pneumonia (N = 9, 23%), ICU admission (N = 9, 23%) and mechanical ventilation (N = 7, 18%). Three deaths (7.5%) were attributed to influenza, all of whom had lower respiratory tract infection (LRTI). Patients with LRTI (N = 18, 45%) also had a higher 30-day mortality (37 versus 0%) and 90-day mortality (42 versus 0%) than those with upper respiratory tract infection. In summary, neutropenic patients have high rates of influenza complications. Our study highlights the need for early diagnosis and aggressive management of influenza in this population.

Failure mode and effects analysis to reduce risk of anticoagulation levels above the target range during concurrent antimicrobial therapy

PURPOSE

A failure mode and effects analysis (FMEA) was conducted to analyze the clinical and operational processes leading to above-target International Normalized Ratios (INRs) in warfarin-treated patients receiving concurrent antimicrobial therapy.

METHODS

The INRs of patients on long-term warfarin therapy who received a course of trimethoprim-sulfamethoxazole, metronidazole, fluconazole, miconazole, or voriconazole (highly potentiating antimicrobials, or HPAs) between September 1 and December 31, 2011, were compared with patients on long-term warfarin therapy who did not receive any antimicrobial during the same period. A multidisciplinary team of physicians, pharmacists, and a systems analyst was then formed to complete a step-by-step outline of the processes involved in warfarin management and concomitant HPA therapy, followed by an FMEA.

RESULTS

Patients taking trimethoprim-sulfamethoxazole, metronidazole, or fluconazole demonstrated a significantly increased risk of having an INR of >4.5. The FMEA identified 134 failure modes. The most common failure modes were as follows: (1) electronic medical records did not identify all patients receiving warfarin, (2) HPA prescribers were unaware of recommended warfarin therapy when HPAs were prescribed, (3) HPA prescribers were unaware that a patient was taking warfarin and that the drug interaction is significant, and (4) warfarin managers were unaware that an HPA had been prescribed for a patient.

CONCLUSION

An FMEA determined that the risk of adverse events caused by concomitantly administering warfarin and HPAs can be decreased by preemptively identifying patients receiving warfarin, having a care process in place, alerting providers about the patient's risk status, and notifying providers at the anticoagulation clinic.

Emerging issues in gram-negative bacterial resistance: an update for the practicing clinician

The rapid and global spread of antimicrobial-resistant organisms in recent years has been unprecedented. Although resistant gram-positive infections have been concerning to clinicians, the increasing incidence of antibiotic-resistant gram-negative infections has become the most pressing issue in bacterial resistance. Indiscriminate antimicrobial use in humans and animals coupled with increased global connectivity facilitated the transmission of gram-negative infections harboring extended-spectrum β-lactamases in the 1990s. Carbapenemase-producing Enterobacteriaceae, such as those containing Klebsiella pneumoniae carbapenemases and New Delhi metallo-β-lactamases, have been the latest scourge since the late 1990s to 2000s. Besides β-lactam resistance, these gram-negative infections are often resistant to multiple drug classes, including fluoroquinolones, which are commonly used to treat community-onset infections. In certain geographic locales, these pathogens, which have been typically associated with health care-associated infections, are disseminating into the community, posing a significant dilemma for clinicians treating community-onset infections. In this Concise Review, we summarize emerging trends in antimicrobial resistance. We also review the current knowledge on the detection, treatment, and prevention of infection with these organisms, with a focus on the carbapenemase-producing gram-negative bacilli. Finally, we discuss emerging therapies and areas that need further research and effort to stem the spread of antimicrobial resistance.

Serum peak sulfamethoxazole concentrations demonstrate difficulty in achieving a target range: a retrospective cohort study

OBJECTIVES

Trimethoprim (TMP)/sulfamethoxazole (SMX) has consistently demonstrated great interindividual variability. Therapeutic drug monitoring may be used to optimize dosing. Optimal peak SMX concentration has been proposed as 100 to 150 μg/mL. The objective of our work was to determine the success rate of a TMP/SMX dosing guideline in achieving a targeted serum peak SMX concentration range.

METHODS

Our retrospective cohort study enrolled 305 adult hospitalized patients who received treatment with TMP/SMX and underwent serum peak SMX concentration monitoring from January 2003 to November 2011. Patients receiving low-dose TMP/SMX therapy (TMP <15 mg/kg/d) were compared with those receiving high-dose therapy (TMP >15 mg/kg/d).

RESULTS

Patients were classified into peak and modified peak SMX concentration cohorts based on time between TMP/SMX dose and SMX quantification. The association between dosing group and the outcome of the SMX level within the goal range was measured using logistic regression models. The primary outcome measured was serum peak SMX concentration 100 to 150 μg/mL. Serum peak SMX concentrations were attained within range for the peak and modified peak cohort 29% and 26% of the time, respectively. The median peak SMX concentration was 144 μg/mL (range 25-471 μg/mL). The low daily dose cohort demonstrated a trend toward improvement in the odds of target peak concentration range attainment. The results were similar regardless of the method used to adjust for baseline characteristics. The pure peak and modified peak cohorts had 44% and 46% of patients with above-target SMX peak concentrations, respectively.

CONCLUSIONS

Attainment of the intended target concentration range was low with no difference in attainment between the low-dose and high-dose cohorts. Higher proportions of patients had an above-target SMX peak, which may indicate that the dosing algorithm is overly aggressive in obtaining the therapeutic goal.

Antineoplastic Agents and the Associated Myelosuppressive Effects

Bone marrow is a complex organ responsible for the regulation of hematopoietic cell distribution throughout the human body. Patients receiving antineoplastic agents as a therapeutic intervention for hematologic malignancy often experience varying degrees of myelotoxicity. Antineoplastic agents cause hypocellularity in marrow resulting in a reduction in hematopoietic tissue activity and a corresponding decline in cell production. Quantifying the adverse effects on hematopoiesis is based on the properties of a single agent, the use of individual drugs within a combination chemotherapy regimen, and the course, or courses, of chemotherapy designed to treat cancer. The direct or indirect suppression of erythrocytes, granulocytes, and megakaryocytes has potential for multiple negative clinical consequences ranging from increased monitoring of blood counts to life-threatening infection and death. This review will provide an overview of the structure and function of competent adult bone marrow, describe the process of hematopoiesis, and characterize the myelotoxicities associated with common antineoplastic agents currently used in the treatment of cancer.

Cefpodoxime for antimicrobial prophylaxis in neutropenia: a retrospective case series

BACKGROUND

Antimicrobial prophylaxis in select neutropenic patients has reduced fever, infection rates, hospital length of stay, and hospitalization rates. Guidelines from the Infectious Diseases Society of America recommend the consideration of prophylaxis with a fluoroquinolone in patients at high risk for infection after chemotherapy. The use of fluoroquinolones has been associated with many adverse events, and there is limited evidence on alternative antimicrobial prophylaxis in patients intolerant of fluoroquinolones.

OBJECTIVES

Our study describes a single-center experience of cefpodoxime as an alternative to fluoroquinolones for antibacterial prophylaxis during neutropenia after chemotherapy and represents a retrospective evaluation of an oral cephalosporin in adult patients for this purpose.

METHODS

This retrospective case series analyzed data from the electronic medical records of 41 patients having hematologic malignancies and given cefpodoxime for neutropenic prophylaxis.

RESULTS

The rate of febrile neutropenia was 85%, with 60% culture-positive infections. Gram-positive organisms were identified in 52% of positive cultures, and gram-negative organisms represented 40% of positive cultures. Antimicrobial resistance to guideline-recommended empiric treatment regimens was not seen in breakthrough infections.

CONCLUSIONS

Cefpodoxime can be utilized for prophylaxis, without adversely affecting resistance to broad-spectrum agents, and maintains a high level of appropriateness of guideline-recommended empiric regimens. This study of cefpodoxime prophylaxis in adult patients intolerant to fluoroquinolones adds to the literature of potential alternative agents for prophylaxis in neutropenic patients.

The incidence of invasive fungal infections in neutropenic patients with acute leukemia and myelodysplastic syndromes receiving primary antifungal prophylaxis with voriconazole

The objective of this study is to characterize the outcomes of primary antifungal prophylaxis with voriconazole in patients receiving intensive chemotherapy for acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS). We conducted a single center, retrospective, cohort study of consecutive adult patients with AML or MDS at Mayo Clinic between January 1, 2006 and July 1, 2010. The study included patients undergoing induction or first relapse combination chemotherapy who received voriconazole 200 mg orally twice daily as prophylaxis during the neutropenic phase. Patient records were evaluated until 30 days after neutrophil recovery for development of invasive fungal infection (IFI) as defined per EORTC/MSG 2008 criteria with computed tomography scans independently reviewed by a radiologist. Therapeutic drug monitoring and reasons for voriconazole discontinuation were documented. Twenty four episodes of IFI were detected among 165 consecutive patients for an overall incidence of 145 per 1000 patients. The incidence of IFI was 24, 42, and 78 per 1000 patients for proven, probable, and possible infection, respectively. Four patients developed proven IFI (n = 2 Aspergillus spp., n = 2 Rhizopus spp.). Serum voriconazole trough concentrations were available in 39 patients, and no statistically significant difference in voriconazole trough level was observed between those with versus without an IFI. Voriconazole prophylaxis was discontinued in 81 patients due to suspected IFI (n = 24), fever of unknown origin (n = 19), adverse events (n = 23), and other causes (n = 17). Voriconazole as primary IFI prophylaxis is safe and may be beneficial in AML/MDS patients receiving intensive chemotherapy.

Characterization of bacterial infections in allogeneic hematopoietic stem cell transplant recipients who received prophylactic levofloxacin with either penicillin or doxycycline

OBJECTIVE

To describe the effect of a combination prophylactic regimen of levofloxacin, a synthetic chemotherapeutic antibiotic of the fluoroquinolone drug class, with either penicillin or doxycycline on the changing epidemiology of bacterial infections and antimicrobial resistance patterns of isolated organisms in the allogeneic hematopoietic stem cell transplant (HSCT) patient population.

PATIENTS AND METHODS

We conducted a single-center, retrospective cohort study of all allogeneic HSCT recipients from January 1, 2003, through August 31, 2008, who received prophylactic levofloxacin in combination with penicillin (or with doxycycline in penicillin-allergic patients) from allogeneic stem cell infusion until neutrophil engraftment.

RESULTS

Of the 258 patients who underwent allogeneic HSCT during the study period, 231 received levofloxacin prophylaxis, 76 (33%) of whom developed an infection within 3 months after transplant. Over time, the ratio of gram-positive to gram-negative (GN) infections decreased from 2.11 in 2004, the first year that GN organisms were isolated, to 1.11 in 2008 (P=.20). Emergence of fluoroquinolone-resistant GN bacteria was observed (P=.02), whereas resistance to extended-spectrum beta-lactams did not change over time. Combined vancomycin-resistant enterococci colonization and infection rates increased during the study period (P=.04). Clostridium difficile colitis was uncommon.

CONCLUSION

Levofloxacin with penicillin or doxycycline prophylaxis may contribute to the emergence of resistant GN infections in allogeneic HSCT recipients over time. Our findings provide additional support for the current standard of practice of administering empiric monotherapy with an antipseudomonal beta-lactam if these patients develop fever or are suspected to have an infection.