SARS-CoV-2 in immunocompromised individuals.

Immunocompromised individuals and particularly those with hematologic malignancies are at increased risk for SARS-CoV-2-associated morbidity and mortality due to immunologic deficits that limit prevention, treatment, and clearance of the virus. Understanding the natural history of viral infections in people with impaired immunity due to underlying conditions, immunosuppressive therapy, or a combination thereof has emerged as a critical area of investigation during the COVID-19 pandemic. Studies focused on these individuals have provided key insights into aspects of innate and adaptive immunity underlying both the antiviral immune response and excess inflammation in the setting of COVID-19. This review presents what is known about distinct states of immunologic vulnerability to SARS-CoV-2 and how this information can be harnessed to improve prevention and treatment strategies for immunologically high-risk populations.

Prevalence of Enteric Infections in Patients on Immune Checkpoint Inhibitors and Impact on Management and Outcomes.

BACKGROUND: Stool pathogen testing is recommended as part of the initial evaluation for patients with new-onset diarrhea on immune checkpoint inhibitors (ICIs), yet its significance has not been well-studied. We aimed to determine the impact of multiplex gastrointestinal (GI) pathogen PCR testing on the clinical course and use of immunosuppressive therapy in patients who develop diarrhea on ICIs. METHODS: This retrospective cohort included individuals who underwent GI pathogen panel PCR for diarrhea on ICIs at Memorial Sloan Kettering between 7/2015 and 7/2021. The primary outcome was use of immunosuppressive therapy for suspected immunotherapy-related enterocolitis (irEC). Secondary outcomes included diarrhea severity and endoscopic and histologic disease patterns. RESULTS: Among 521 ICI-treated patients tested for GI pathogens, 61 (11.7%) had a positive PCR. Compared to patients without detectable infections, patients with infections had more frequent grades 3-4 diarrhea (37.7% vs. 19.6%, P < .01) and colitis (39.3% vs. 14.7%, P < .01). However, patients with infections did not have higher rates of persistent or recurrent diarrhea and were less likely to receive steroids (P < .01) and second-line immunosuppressive agents (P = .03). In 105 patients with lower endoscopy, similar trends were observed and no differences in endoscopic severity or histologic patterns were noted between groups. CONCLUSIONS: GI infections in ICI-treated patients presenting with diarrhea are linked to more severe but self-limited clinical presentations and may be optimally treated with observation and supportive care alone. Routine and timely stool pathogen testing may help avert unnecessary empiric immunosuppression for suspected irEC, which has been linked to blunted antitumor responses and numerous adverse effects.

Prevalence of astrovirus and sapovirus among adult oncology patients with acute gastroenteritis using a multiplexed gastrointestinal pathogen PCR panel.

BACKGROUND: Multiplex syndromic gastrointestinal panels (GIPCR) have streamlined the diagnosis of infectious diarrhea. Additionally, they have expanded the number of pathogens that can be routinely evaluated, allowing further understanding of the prevalence of enteric pathogens in various patient populations. The goal of this study was to investigate the prevalence and clinical presentation of astrovirus and sapovirus gastroenteritis in adult oncology patients as detected by the FilmArray GIPCR. METHODS: All GIPCR panel results from December 2017 to June 2021 were retrospectively reviewed to determine the prevalence of astrovirus and sapovirus in adult oncology patients. Medical records were also reviewed to obtain clinical information. Repeat GIPCR positivity and symptom duration were used to estimate prolonged viral shedding. RESULTS: A total of 18,014 panels were performed on samples collected from 9303 adults. Overall, astrovirus and sapovirus were detected in 0.35% (33/9303) and 0.45% (42/9303) GIPCRs respectively. At least one viral target was detected in 424 (4.4%) patients. Astrovirus accounted for 7.8% (33/424) and sapovirus 9.9% (42/424) of patients. Diarrhea was the most common symptom documented. A subset of transplant patients had protracted viral detection with a median of ~27 days (range 23-43 days) for astrovirus and 97 days (range 11-495) for sapovirus. No clusters or outbreaks were identified during the study period. CONCLUSION: In oncology patients with viral gastroenteritis, astrovirus and sapovirus were the causative agents in 18% of the cases. Both viruses were associated with mild disease. Prolonged diarrhea and viral shedding were observed in a few transplant patients.

Management of a major varicella zoster exposure in a pediatric oncology population.

Management of the exposure of pediatric oncology patients to varicella zoster virus (VZV) is controversial. We report the exposure of 56 patients to a single child with chicken pox at a pediatric cancer housing facility and describe our strategic approach for their management. We reviewed the immune and clinical status of 56 children with cancer receiving ongoing treatment at Memorial Sloan Kettering Cancer Center (MSK) who, while living at a pediatric cancer housing facility, were exposed to the index patient. The management of patients exposed included: (1) determination of immune status, (2) availability of vaccination history or VZV disease prophylaxis, (3) exposure status and subsequent isolation during the period of incubation, and (4) VZV disease prophylaxis. In addition to the 56 patients exposed to the index case, eight children with cancer treated at other facilities and 11 healthy siblings living in the facility were exposed. Of the 56 MSK patients, 21 were classified as immunosuppressed and received varicella zoster immune globulin (human), intravenous standard immune globulin, or acyclovir based on serostatus and immune function. The cohort was followed for 4 weeks after the exposure and no secondary infections were diagnosed. We performed a risk assessment and created a management plan to control and prevent further exposure and development of disease. No secondary cases developed. This strategic approach could serve as a model for the management of VZV exposure for other pediatric oncology centers.

Predictors of Coronavirus Disease 2019 Hospitalization After Sotrovimab in Patients With Hematologic Malignancy During the BA.1 Omicron Surge.

BACKGROUND: Sotrovimab is an anti-spike neutralization monoclonal antibody developed to reduce the risk of coronavirus disease 2019 (COVID-19) progression and advancement to hospitalization in high-risk patients. Currently, there is limited research describing the association of sotrovimab treatment in patients with hematologic malignancy and the predictive factors of hospitalization. METHODS: We performed an observational study of 156 consecutive cancer patients who received sotrovimab at Memorial Sloan Kettering Cancer Center in New York City during the BA.1 Omicron surge. We evaluated the demographic, clinical, and laboratory characteristics of the patients who had subsequent COVID-19-related hospitalization(s) compared to those who did not. RESULTS: Among the 156 study patients, 17 (11%) were hospitalized, of whom 4 were readmitted for COVID-19-related complications; 3 deaths were attributed to COVID-19. Results from multivariable logistic regression show that significant factors associated with hospitalization include patients on anti-CD20 therapy (adjusted odds ratio [aOR], 5.59 [95% confidence interval {CI}, 1.73-18.12]; P = .004) and with relapse/refractory disease (aOR, 5.69 [95% CI, 1.69-19.16]; P = .005). Additionally, whole genome sequencing of severe acute respiratory syndrome coronavirus 2 detected high occurrences of mutations in the spike gene associated with treatment-related resistance longitudinal samples from 11 patients treated with sotrovimab. CONCLUSIONS: While sotrovimab is effective at reducing COVID-19 hospitalization and disease severity in patients with hematologic malignancy when administered early, patients who received anti-CD20 antibodies showed substantial morbidity. Due to the high potential for resistance mutation to sotrovimab and increased morbidity in patients on anti-CD20 therapy, combination treatment should be explored to determine whether it provides added benefits compared to monotherapy.

Predictors of SARS-CoV-2 Omicron breakthrough infection after receipt of AZD7442 (tixagevimab-cilgavimab) for pre-exposure prophylaxis among hematologic malignancy patients.

AZD7442 (tixagevimab-cilgavimab) is a combination of two human monoclonal antibodies for pre-exposure prophylaxis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among high-risk patients who do not mount a reliable vaccine response. Foremost among these are hematologic malignancy patients with limited clinical trial or realworld experience to assess the effectiveness of this combination treatment since the emergence of Omicron and its subvariants. We performed a retrospective study of 892 high-risk hematologic malignancy patients who received AZD7442 at Memorial Sloan Kettering Cancer Center in New York City from January 1, 2022 to July 31, 2022. We evaluated demographic, clinical, and laboratory characteristics and performed regression analyses to evaluate risk factors for breakthrough infection. We also evaluated the impact of updated AZD7442 dosing regimens on the risk of breakthrough infection. Among 892 patients, 98 (10.9%) had a breakthrough infection during the study period. A majority received early outpatient treatment (82%) and eventually eight (8.2%) required hospitalization for management of Coronavirus Disease 2019 (COVID-19), with a single instance of severe COVID-19 and death. Patients who received a repeat dose or a higher firsttime dose of AZD7442 had a lower incidence of breakthrough infection. Univariate analyses did not reveal any significant predictors of breakthrough infection. While AZD7442 is effective at reducing SARS-CoV-2 breakthrough infection in patients with hematologic malignancies, no risk factors reliably predicted risk of infection. Patients who received updated dosing regimens as per Food and Drug Administration guidelines had better protection against breakthrough infection.

Risk of Healthcare-Associated Transmission of Sever Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Hospitalized Cancer Patients.

BACKGROUND: There is limited information on the risk of hospital-acquired coronavirus disease 2019 (COVID-19) among high-risk hospitalized patients after exposure to an infected patient or healthcare worker (HCW) in a nonoutbreak setting. METHODS: This study was conducted at a tertiary care cancer center in New York City from 10 March 2020 until 28 February 2021. In early April 2020, the study institution implemented universal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing at admission and retesting every 3 days through the hospital stay. Contact tracing records were reviewed for all exposures to SARS-CoV-2 positive patients and HCWs. RESULTS: From 10 March 2020 to 28 February 2021, 11 348 unique patients who were SARS-CoV-2 polymerase chain reaction (PCR) negative at the time of admission underwent 31 662 postadmission tests during their hospitalization, and 112 tested positive (0.98%). Among these, 49 patients housed in semiprivate rooms during admission resulted in 74 close contacts and 14 secondary infections within 14 days, for an overall attack rate of 18.9%. Among those exposed to a roommate undergoing an aerosol-generating procedure (AGP), the attack rate was 35.7%. Whole genome sequencing (WGS) corroborated transmission in 6/8 evaluated pairs. In addition, three transmission events occurred in 214 patients with significant exposure to 105 COVID-19 positive healthcare workers (1.4%). CONCLUSIONS: The overall risk of hospital-acquired COVID-19 is low for hospitalized cancer patients, even during periods of high community prevalence. However, shared occupancy with an unrecognized case is associated with a high secondary attack rate in exposed roommates.

Clinical and Genomic Characterization of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS CoV-2) Infections in mRNA Vaccinated Health Care Personnel in New York City.

BACKGROUND: Vaccine-induced clinical protection against severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) variants is an evolving target. There are limited genomic level data on SARS CoV-2 breakthrough infections and vaccine effectiveness (VE) since the global spread of the B.1.617.2 (Delta) variant. METHODS: In a retrospective study from 1 November 2020 to 31 August 2021, divided as pre-Delta and Delta-dominant periods, laboratory-confirmed SARS CoV-2 infections among healthcare personnel (HCP) at a large tertiary cancer center in New York City were examined to compare the weekly infection rate-ratio in vaccinated, partially vaccinated, and unvaccinated HCP. We describe the clinical and genomic epidemiologic features of post-vaccine infections to assess for selection of variants of concern (VOC)/variants of interest (VOI) in the early post-vaccine period and impact of B.1.617.2 (Delta) variant domination on VE. RESULTS: Among 13658 HCP in our cohort, 12379 received at least 1 dose of a messenger RNA (mRNA) vaccine. In the pre-Delta period overall VE was 94.5%. Whole genome sequencing (WGS) of 369 isolates in the pre-Delta period did not reveal a clade bias for VOC/VOI specific to post-vaccine infections. VE in the Delta dominant phase was 75.6%. No hospitalizations occurred among vaccinated HCP in the entire study period, compared to 17 hospitalizations and 1 death among unvaccinated HCP. CONCLUSIONS: Findings show high VE among HCP in New York City in the pre-Delta phase, with moderate decline in VE post-Delta emergence. SARS CoV-2 clades were similarly distributed among vaccinated and unvaccinated infected HCP without apparent clustering during the pre-Delta period of diverse clade circulation. Strong vaccine protection against hospitalization was maintained through the entire study period.

Long and persistent COVID-19 in patients with hematologic malignancies: from bench to bedside.

PURPOSE OF REVIEW: Cancer patients, especially those with hematologic malignancies, are at increased risk for coronavirus disease 2019 (COVID-19)-related complications and mortality. We describe the incidence, clinical characteristics, risk factors, and outcomes of persistent COVID-19 infection in patients with hematologic malignancies. RECENT FINDINGS: The syndrome of persistent COVID-19 in patients with hematologic malignancies manifests as a chronic protracted illness marked by waxing and waning or progressive respiratory symptoms and prolonged viral shedding. Immunosuppressed patients with lymphoid malignancies may serve as partially immune reservoirs for the generation of immune-evasive viral escape mutants. SUMMARY: Persistent COVID-19 infection is a unique concern in patients with hematologic malignancies. While vaccination against severe acute respiratory syndrome coronavirus 2 has reduced the overall burden of COVID-19 in patients with hematologic cancers, whether vaccination or other novel treatments for COVID-19 prevent or alleviate this syndrome remains to be determined.

Immune-Related Adverse Events Among COVID-19-Vaccinated Patients With Cancer Receiving Immune Checkpoint Blockade.

BACKGROUND: Whether COVID-19 vaccination and the associated immune response increases susceptibility to immune-related adverse events (irAEs) among patients treated with immune checkpoint inhibition (ICI) remains unknown. Short-term follow-up can assess the safety of concurrent administration of the vaccine and ICI treatment. METHODS: We conducted an electronic health record analysis of a cohort of 408 patients with cancer receiving ICI therapy and who were vaccinated for COVID-19 between January 16 and March 27, 2021. Patients were seen in follow-up for 90 days from the day of the first dose in this single-institution tertiary care center. We evaluated the incidence of irAEs and the frequency of each event type and grade among patients who experienced an irAE. We also evaluated the incidence of irAEs in patients who began a new immunotherapy agent after vaccination. RESULTS: Among 408 patients with cancer receiving ICI therapy (median age, 71 years; 217 [53%] male), administration of a COVID-19 mRNA vaccine within 90 days of ICI treatment was not associated with an increased incidence of irAEs. A total of 27 (7%) patients experienced a new irAE within the observation period. Among patients with previous irAEs from ICIs (n=54), 3 (6%) experienced a recurrent irAE, and of those initiating a new immunotherapy (n=52), 9 (17%) experienced an irAE. No excess risk of COVID-19 diagnosis was seen in this subset of patients receiving ICI therapy, and no breakthrough COVID-19 cases were seen after full COVID-19 vaccination. CONCLUSIONS: These findings should reassure providers that COVID-19 vaccination during ICI therapy is safe and efficacious.

Fecal Microbiota Transplantation Is Safe for Clostridiodies difficile Infection in Patients with Solid Tumors Undergoing Chemotherapy.

BACKGROUND: Recurrent Clostridiodies difficile infection (CDI) contributes to morbidity and mortality in cancer patients. Fecal microbiota transplantation (FMT) has been proven to be effective in treatment of recurrent CDI, but immunocompromised patients have been excluded from prospective studies due to safety concerns. The aim of this study was to investigate the safety of FMT for recurrent CDI in immunocompromised patients with solid tumor malignancy undergoing chemotherapy. METHODS: This was a single center, prospective observational study of patients at a tertiary care cancer center of 10 patients with recurrent CDI who were at least 18 years of age, with a solid tumor malignancy who had received chemotherapy within the previous 6 months. Patients received FMT either by upper endoscopy or colonoscopy and were followed for 6 months. Safety was a primary outcome measured by infections occurring within 2 weeks of FMT. Efficacy of FMT was also evaluated. RESULTS: Nineteen patients were evaluated. On applying exclusion criteria, 10 were included in the study. One patient requested to be off study within 2 weeks and was considered a treatment failure. Seven received FMT via upper endoscopy, three via colonoscopy. There were no infectious complications from FMT. Eight patients (80%) were cured after the first FMT. All eight patients went on to restart oncologic treatment with an average of 32.5 days after FMT. CONCLUSIONS: FMT is safe and effective for recurrent CDI in solid tumor patients undergoing chemotherapy. Patients can resume oncologic treatment after FMT.

Severe Acute Respiratory Syndrome Coronavirus 2 Surveillance and Exposure in the Perioperative Setting With Universal Testing and Personal Protective Equipment Policies.

BACKGROUND: New York City (NYC) experienced a surge of coronavirus disease 2019 (COVID-19) cases in March and April 2020. Since then, universal polymerase chain reaction (PCR)-based surveillance testing and personal protective equipment (PPE) measures are in wide use in procedural settings. There is limited published experience on the utility and sustainability of PCR-based surveillance testing in areas with receding and consistently low community COVID-19 rates. METHODS: The study was conducted at a tertiary care cancer center in NYC from 22 March to 22 August 2020. Asymptomatic patients underwent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing before surgeries, interventional radiology procedures, and endoscopy. Contact tracing in procedural areas was done if a patient with an initial negative screen retested positive within 48 hours of the procedure. RESULTS: From March 22 until August 22, 2020, 11 540 unique patients underwent 14 233 tests before surgeries or procedures at Memorial Sloan Kettering Cancer Center. Overall, 65 patients were positive, with a peak rate of 4.3% that fell below 0.3% after April 2020. Among the 65 positive cases, 3 were presymptomatic and 38 were asymptomatic. Among asymptomatic test-positive patients, 76% had PCR cycle threshold >30 at first detection. Five patients tested newly positive in the immediate postoperative period, exposing 82 employees with 1 case of probable transmission (1.2%). CONCLUSIONS: The prevalence of SARS-CoV-2 infection identified on preprocedural surveillance was low in our study, which was conducted in an area with limited community spread at the later stage of the study. Universal PPE is protective in procedural settings. Optimal and flexible diagnostic strategies are needed to accomplish and sustain the goals of comprehensive preprocedure surveillance testing.

Evaluation of a Combined Multilocus Sequence Typing and Whole-Genome Sequencing Two-Step Algorithm for Routine Typing of Clostridioides difficile.

Multilocus sequence typing (MLST) is a low-resolution but rapid genotyping method for Clostridioides difficile Whole-genome sequencing (WGS) has emerged as the new gold standard for C. difficile typing, but cost and lack of standardization still limit broad utilization. In this study, we evaluated the potential to combine the portability of MLST with the increased resolution of WGS for a cost-saving approach to routine C. difficile typing. C. difficile strains from two New York City hospitals (hospital A and hospital B) were selected. WGS single-nucleotide polymorphism (wgSNP) was performed using established methods. Sequence types (ST) were determined using PubMLST, while wgSNP analysis was performed using the Bionumerics software. An additional analysis of a subset of data (hospital A) was made comparing the Bionumerics software to the CosmosID pipeline. Cost and turnaround time to results were compared for the algorithmic approach of MLST followed by wgSNP versus direct wgSNP. Among the 202 C. difficile isolates typed, 91% (n = 185/203) clustered within the representative ST, showing a high agreement between MLST and wgSNP. While clustering was similar between the Bionumerics and CosmosID pipelines, large differences in the overall number of SNPs were noted. A two-step algorithm for routine typing results in significantly lower cost than routine use of WGS. Our results suggest that using MLST as a first step in routine typing of C. difficile followed by WGS for MLST concordant strains is a less technically demanding, cost-saving approach for performing C. difficile typing than WGS alone without loss of discriminatory power.

Lower Rate of Seropositivity to Measles Among Young Healthcare Personnel in New York City.

We examined the prevalence of measles antibody among 12 349 newly hired HCP between 2009 and 2019. Younger HCP were significantly more likely to have no immunity. Compared with a 92.2% seropositive rate among 1057 persons hired at age >50 years, only 84.4% of approximately 10 000 HCP aged <40 years had protective antibody.

Safety of Inactivated Influenza Vaccine in Cancer Patients Receiving Immune Checkpoint Inhibitors.

BACKGROUND: Cancer patients are at a higher risk for developing influenza (flu)- related complications. It is unclear if the flu vaccine exacerbates immune events in patients treated with immune checkpoint inhibitors (ICIs). METHODS: We conducted an institutional review board-IRB-approved retrospective review of advanced cancer patients on ICIs who received the flu vaccine during three 3 consecutive seasons: 2014-2015, 2015-2016, and 2016-2017. The primary outcome assessed was any "new onset" immune-related adverse event (IRAE). A subset analysis of vaccinated patients newly treated with anti-programmed cell death protein 1 (PD-1) agents (nivolumab or pembrolizumab) was conducted to assess overall IRAE rates for comparison with published clinical trials. RESULTS: During the three 3 seasons, 370 patients met criteria for ICI and vaccination within ~ twoapproximately 2 months (65 days). The most common underlying cancers were lung (46%) and melanoma (19%); 61% of patients received an anti-PD-1 agent only. In the entire cohort, 20% experienced an IRAE (any grade); incidence of grade 3 or 4 toxicity was 8%. No grade 5 events occurred. In the subset of 170 patients newly treated with anti-PD-1 agents, the overall IRAE rate was 18% and, grade 3/4 events occurred in 7.6%. Influenza was diagnosed in 2 patients. CONCLUSIONS: No increase in incidence or severity of IRAEs was detected in patients on ICIs who received the inactivated influenza vaccine within ~ approximately 2 months of ICI. For newly treated patients on anti-PDI-1 agents, IRAE rates were comparable to those from published clinical trials and did not vary with order of administration. Routine seasonal flu vaccination is encouraged in patients on ICIs.

Guidelines for COVID-19 Management in Hematopoietic Cell Transplantation and Cellular Therapy Recipients.

There are currently limited data on the epidemiology, clinical manifestations, and optimal management of Coronavirus Disease 2019 (COVID-19) in hematopoietic cell transplantation and cellular therapy recipients. Given the experience with other respiratory viruses, we anticipate that patients may develop severe clinical disease and thus provide the following general principles for cancer centers across the nation. These guidelines were developed by members of the American Society for Transplantation and Cellular Therapy Infectious Diseases Special Interest Group. Specific practices may vary depending on local epidemiology and testing capacity, and the guidance provided in this document may change as new information becomes available.

Systems-level analysis of NalD mutation, a recurrent driver of rapid drug resistance in acute Pseudomonas aeruginosa infection.

Pseudomonas aeruginosa, a main cause of human infection, can gain resistance to the antibiotic aztreonam through a mutation in NalD, a transcriptional repressor of cellular efflux. Here we combine computational analysis of clinical isolates, transcriptomics, metabolic modeling and experimental validation to find a strong association between NalD mutations and resistance to aztreonam-as well as resistance to other antibiotics-across P. aeruginosa isolated from different patients. A detailed analysis of one patient's timeline shows how this mutation can emerge in vivo and drive rapid evolution of resistance while the patient received cancer treatment, a bone marrow transplantation, and antibiotics up to the point of causing the patient's death. Transcriptomics analysis confirmed the primary mechanism of NalD action-a loss-of-function mutation that caused constitutive overexpression of the MexAB-OprM efflux system-which lead to aztreonam resistance but, surprisingly, had no fitness cost in the absence of the antibiotic. We constrained a genome-scale metabolic model using the transcriptomics data to investigate changes beyond the primary mechanism of resistance, including adaptations in major metabolic pathways and membrane transport concurrent with aztreonam resistance, which may explain the lack of a fitness cost. We propose that metabolic adaptations may allow resistance mutations to endure in the absence of antibiotics and could be targeted by future therapies against antibiotic resistant pathogens.

Clinical Performance of (1,3) Beta-D Glucan for the Diagnosis of Pneumocystis Pneumonia (PCP) in Cancer Patients Tested With PCP Polymerase Chain Reaction.

BACKGROUND: Serum (1,3)-beta-D glucan (BDG) is increasingly used to guide the management of suspected Pneumocystis pneumonia (PCP). BDG lacks specificity for PCP, and its clinical performance in high-risk cancer patients has not been fully assessed. Polymerase chain reaction (PCR) for PCP detection is highly sensitive, but cannot differentiate between colonization and infection. We evaluated the diagnostic performance of serum BDG in conjunction with PCP PCR on respiratory samples in patients with cancer and unexplained lung infiltrates. METHODS: We performed a retrospective analysis of adult patients evaluated for PCP at our institution from 2012 to 2015, using serum BDG and PCP PCR. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the serum BDG at different thresholds were evaluated using PCP PCR alone or in conjunction with clinical presentation in PCP PCR-positive patients. RESULTS: With PCP PCR alone as the reference method, BDG (≥80 pg/mL) had a sensitivity of 69.8%, specificity of 81.2%, PPV of 34.6%, and NPV of 95.2% for PCP. At ≥200 pg/mL in patients with a positive PCR and a compatible PCP clinical syndrome, BDG had a sensitivity of 70%, specificity of 100%, PPV of 100%, and NPV of 52.0% for PCP. CONCLUSIONS: Patients negative by both BDG and PCR were unlikely to have PCP. In patients with a compatible clinical syndrome for PCP, higher BDG values (>200 pg/mL) were consistently associated with clinically-significant PCP infections among PCP PCR-positive oncology patients.

Risk for Clostridiodes difficile Infection among Older Adults with Cancer.

To assess whether risk for Clostridiodes difficile infection (CDI) is higher among older adults with cancer, we conducted a retrospective cohort study with a nested case-control analysis using population-based Surveillance, Epidemiology, and End Results-Medicare linked data for 2011. Among 93,566 Medicare beneficiaries, incident CDI and odds for acquiring CDI were higher among patients with than without cancer. Specifically, risk was significantly higher for those who had liquid tumors and higher for those who had recently diagnosed solid tumors and distant metastasis. These findings were independent of prior healthcare-associated exposure. This population-based assessment can be used to identify targets for prevention of CDI.

Impact of Empiric Treatment for Vancomycin-Resistant Enterococcus in Colonized Patients Early after Allogeneic Hematopoietic Stem Cell Transplantation.

In recent years, vancomycin-resistant Enterococcus (VRE) colonization is being increasingly encountered in transplant recipients, and VRE has become one of the leading causes of bacteremia early after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Data are sparse on the effect of empiric VRE therapy for febrile, neutropenic allo-HSCT recipients colonized with VRE. All allo-HSCT recipients aged ≥18years who developed VRE bacteremia (VREB) between 2005 and 2014 were identified and categorized as to whether they received empiric or directed VRE therapy. There were 434 (33%) VRE-colonized and 872 (67%) non-VRE-colonized patients during the study period, and 172 of the 434 (40%) VRE-colonized patients received empiric therapy. There was no significant difference in incidence of VREB among colonized patients who did or did not receive empiric therapy (28 of 172 [16%] vs 55 of 262 [21%]; P = .22). There were 95 patients with VREB, of which the majority (83 of 95; 87%) was known to be VRE-colonized. Of the 95 VREB episodes, 29 (31%) were treated with empiric VRE therapy, whereas 66 (69%) were treated with directed therapy. No significant differences in clinical outcomes, including median duration of bacteremia (2 days vs 2 days; P = .39), recurrent VREB (3 of 29 [10%] vs 5 of 66 [8%]; P = .65), 30-day all-cause mortality (1 of 29 [3%] vs 4 of 66 [6%]; P = .62), or VRE-attributable mortality (1 of 29 [3%] vs 1 of 66 [2%]; P = .55), were observed between the empiric therapy and directed therapy groups. Kaplan-Meier curve analysis showed no significant difference in survival at 30days in allo-HSCT recipients with VREB who received empiric therapy and those who received directed therapy (97% vs 94%; P = .62). Based on our data, we recommend against empiric use of VRE-active agents for fever and neutropenia in VRE-colonized patients undergoing allo-HSCT.