Prospective Assessment of Humoral and Cellular Immune Responses to a Third COVID-19 mRNA Vaccine Dose Among Immunocompromised Individuals

BACKGROUND

Improved coronavirus disease 2019 (COVID-19) prevention is needed for immunocompromised individuals.

METHODS

A prospective study was performed of health care workers (HCW) and immunocompromised participants with baseline serology following 2 mRNA vaccine doses and who were retested after dose 3 (D3); multivariable regression was used to identify predictors of serological responses. IFN-γ/TNF-α T-cell responses were assessed in a subset.

RESULTS

In total, 536 participants were included: 492 immunocompromised (206 solid organ transplant [SOT], 128 autoimmune, 80 hematologic malignancy [HM], 48 solid tumor, 25 HIV), and 44 HCW. D3 significantly increased spike IgG levels among all, but SOT and HM participants had the lowest median antibody levels post-D3 (increase from 0.09 to 0.83 and 0.27 to 1.92, respectively), versus HCW and persons with HIV, autoimmune conditions, and solid tumors (increases from 4.44 to 19.79, 2.9 to 15.75, 3.82 to 16.32, and 4.1 to 25.54, respectively). Seropositivity post-D3 was lowest for SOT (49.0%) and HM (57.8%), versus others (>90%). Neutralization post-D3 was lowest among SOT and HM. Predictors of lower antibody levels included low baseline levels and shorter intervals between vaccines. T-cell responses against spike increased significantly among HCW and nonsignificantly among immunocompromised individuals.

CONCLUSIONS

D3 significantly improves serological but not T-cell responses among immunocompromised individuals. SOT and HM patients have suboptimal responses to D3.

Spike Protein Genetic Evolution in Patients at High Risk of Severe Coronavirus Disease 2019 Treated by Monoclonal Antibodies

BACKGROUND

High-risk patients, often immunocompromised and not responding to vaccine, continue to experience severe coronavirus disease 2019 (COVID-19) and death. Monoclonal antibodies (mAbs) were shown to be effective to prevent severe COVID-19 for these patients. Nevertheless, concerns about the emergence of resistance mutations were raised.

METHODS

We conducted a multicentric prospective cohort study, including 264 patients with mild to moderate COVID-19 at high risk for progression to severe COVID-19 and treated early with casirivimab/imdevimab, sotrovimab, or tixagevimab/cilgavimab. We sequenced the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome during follow-up and searched for emerging spike mutations.

RESULTS

Immunocompromised patients have a 6-fold increased risk of developing mutations, which are associated with a prolonged duration of viral clearance but no clinical worsening. Emerging P337S/R/L/H, E340D/K/A/Q/V/G, and K356T/R substitutions in patients treated with sotrovimab are associated with higher viral RNA loads for up to 14 days post-treatment initiation. Tixagevimab/cilgavimab is associated with a 5-fold increased risk of developing mutations. R346K/I/T/S and K444R/N/M substitutions associated with tixagevimab/cilgavimab have been identified in multiple SARS-CoV-2 lineages, including BQ.1 and XBB.

CONCLUSIONS

The probability of emerging mutations arising in response to mAbs is significant, emphasizing the crucial need to investigate these mutations thoroughly and assess their impact on patients and the evolutionary trajectory of SARS-CoV-2.

Outcomes and clinical characteristics of the compassionate use of plitidepsin in COVID-19 patients with solid tumours, haematological malignancies or anti-CD20 antibody treatment

OBJECTIVE

To study the effect of plitidepsin antiviral treatment in immunocompromised COVID-19 patients with underlying haematological malignancies or solid tumours, particularly those who have undergone anti-CD20 therapies.

DESIGN

We conducted a retrospective observational study, involving 54 adults treated with plitidepsin on compassionate use as an antiviral drug. Our analysis compared outcomes between patients with solid tumours and those with haematological malignancies, and a cohort of cases treated or not with anti-CD20 monoclonal antibodies.

RESULTS

Patients with a history of anti-CD20 therapies showed a prolonged time-to-negative RT-PCR for SARS-CoV-2 infection compared to non-treated patients (33 d (28;75) vs 15 (11;25); p = .002). Similar results were observed in patients with solid tumours in comparison to those with haematological malignancies (13 (10;16) vs 26 (17;50); p < .001). No serious adverse events were documented.

CONCLUSIONS

Patients with haematological malignancies appear to be at a heightened risk for delayed SARS-CoV-2 clearance and subsequent clinical complications. These findings support plitidepsin as a well-tolerated treatment in this high-risk group. A phase II clinical trial (NCT05705167) is ongoing to evaluate plitidepsin as an antiviral drug in this population.KEY POINTSHaematological patients face an increased risk for severe COVID-19.Anti-CD20 therapies could increase fatal outcomes in COVID-19 patients.Persistent viral replication is increased in immunocompromised patients.Plitidepsin does not lead to new serious adverse events in immunocompromised patients.

Protecting the vulnerable: addressing the COVID-19 care needs of people with compromised immunity

While the general population regained a certain level of normalcy with the end of the global health emergency, the risk of contracting COVID-19 with a severe outcome is still a major concern for people with compromised immunity. This paper reviews the impact of COVID-19 on people with immunocompromised status, identifies the gaps in the current management landscape, and proposes actions to address this unmet need. Observational studies have demonstrated that people with immune dysfunction have a higher risk of COVID-19-related hospitalization and death, despite vaccination, than the general population. More research is needed to define the optimal prevention and treatment strategies that are specific to people with immunocompromised status, including novel vaccination strategies, monoclonal antibodies that provide passive immunity and complement suboptimal vaccination responses, and improved and safer antiviral treatment for COVID-19. Preventive measures beyond vaccination alone are urgently needed to protect this vulnerable population.

Post COVID-19 condition imposes significant burden in patients with advanced chronic kidney disease: A nested case-control study

BACKGROUND

The burden of post COVID-19 condition (PCC) is not well studied in patients with advanced kidney disease.

METHODS

A large prospective cohort of SARS-CoV-2 vaccinated patients with chronic kidney disease stages G4-G5 (CKD G4/5), on dialysis, and kidney transplant recipients (KTR) were included. Antibody levels were determined after vaccination. Presence of long-lasting symptoms was assessed in patients with and without prior COVID-19 and compared using logistic regression. In patients with prior COVID-19, PCC was defined according to the WHO definition.

RESULTS

Two hundred sixteen CKD G4/5 patients, 375 dialysis patients, and 2005 KTR were included. Long-lasting symptoms were reported in 204/853 (24%) patients with prior COVID-19 and in 297/1743 (17%) patients without prior COVID-19 (aOR: 1.45 (1.17-1.78)], P < 0.001). PCC was prevalent in 29% of CKD G4/5 patients, 21% of dialysis patients, and 24% of KTR. In addition, 69% of patients with PCC reported (very) high symptom burden. Odds of PCC was lower per 10-fold increase in antibody level after vaccination (aOR 0.82 [0.70-0.96], P = 0.01) and higher in case of COVID-19 related hospital admission (aOR 4.64 [2.61-8.25], P = 0.003).

CONCLUSIONS

CKD G4/5 patients, dialysis patients, and KTR are at risk for PCC with high symptom burden after SARS-CoV-2 vaccination, especially if antibody levels are low and in case of hospitalization due to COVID-19.

Kodamaea ohmeri: A rare yeast causing invasive infections in immunocompromised patients

INTRODUCTION

Kodamaea ohmeri is a rare, recognized pathogen that has previously been isolated from environmental sources. The patients commonly affected by this yeast include immunocompromised as well as immunocompetent patients having several associated risk factors.

METHODOLOGY

We report three cases in which K. ohmeri was isolated from blood using Bact T/ALERT. Identification was carried out by MALDI-TOF MS (Vitek-MS, BioMérieux, Marcy-l'Etoile, France) in addition to color characteristics on chromogenic media. The patients had diminished immune response on account of a multitude of comorbidities.

RESULTS

K. ohmeri can be misidentified as Candida tropicalis, Candida albicans, or Candida hemolounii by conventional methods; correct and timely identification can be achieved by MALDI-TOF MS. Antifungal susceptibility breakpoints for K. ohmeri are currently not defined. An Echinocandin was added to the treatment regimen of all three of the cases.

CONCLUSIONS

Identification of K. ohmeri using conventional methods is difficult and unusual yeasts should be carefully observed, especially upon prolonged incubation.

Risk factors and outcomes of cytomegalovirus infection in the intensive care unit

INTRODUCTION

Cytomegalovirus (CMV) infection has long been recognized as an important viral syndrome in the immunocompromised host. The disease is less well described in critically-ill patients. We evaluated the risk factors for the development of CMV infection in patients admitted to the intensive care unit (ICU). We also compared the outcomes of CMV infection in ICU patients to those of patients with hematological malignancies.

METHODOLOGY

This is a retrospective study composed of three arms: patients admitted to the ICU with infection (ICU + / CMV + arm), patients admitted to the ICU who did not develop CMV infection (ICU + / CMV- arm, and patients with hematological malignancies on the hematology ward without CMV infection (ICU - / CMV + arm).

RESULTS

Patients who were admitted to ICU for surgical causes had a decreased risk of CMV infection. On the other hand, receiving corticosteroids and vasoactive drugs was associated with an increased risk of CMV infection with adjusted odds ratios (aOR) of 2.4 and 25.3, respectively. Mortality was higher in ICU + / CMV + patients compared to ICU - / CMV + patients. In the ICU + /CMV + population, male sex and being on mechanical ventilation after CMV infection were independent predictors of mortality (aOR 4.6 and 5.0, respectively).

CONCLUSIONS

CMV infection in ICU patients is a potentially serious disease requiring close attention. The findings from our study help in identifying patients in the ICU at risk for CMV infection, thereby warranting frequent screening. Patients at high risk of death (male, on mechanical ventilation) should receive prompt treatment and intensive follow-up.

Temporal and spatial dynamics of Listeria monocytogenes central nervous system infection in mice

Listeria monocytogenes is a bacterial pathogen that can cause life-threatening central nervous system (CNS) infections. While mechanisms by which L. monocytogenes and other pathogens traffic to the brain have been studied, a quantitative understanding of the underlying dynamics of colonization and replication within the brain is still lacking. In this study, we used barcoded L. monocytogenes to quantify the bottlenecks and dissemination patterns that lead to cerebral infection. Following intravenous (IV) inoculation, multiple independent invasion events seeded all parts of the CNS from the blood, however, only one clone usually became dominant in the brain. Sequential IV inoculations and intracranial inoculations suggested that clones that had a temporal advantage (i.e., seeded the CNS first), rather than a spatial advantage (i.e., invaded a particular brain region), were the main drivers of clonal dominance. In a foodborne model of cerebral infection with immunocompromised mice, rare invasion events instead led to a highly infected yet monoclonal CNS. This restrictive bottleneck likely arose from pathogen transit into the blood, rather than directly from the blood to the brain. Collectively, our findings provide a detailed quantitative understanding of the L. monocytogenes population dynamics that lead to CNS infection and a framework for studying the dynamics of other cerebral infections.

COVID-19 vaccine efficacy in participants with weakened immune systems from four randomized-controlled trials

BACKGROUND

Although the SARS-CoV-2 vaccines are highly efficacious at preventing severe disease in the general population, current data are lacking regarding vaccine efficacy (VE) for individuals with mild immunocompromising conditions.

METHODS

A post-hoc, cross-protocol analysis of participant-level data from the blinded phase of four randomized, placebo-controlled, COVID-19 vaccine phase 3 trials (Moderna, AstraZeneca, Janssen, and Novavax) was performed. We defined a "tempered immune system" (TIS) variable via a consensus panel based on medical history and medications to determine VE against symptomatic and severe COVID-19 cases in TIS participants versus non-TIS (NTIS) individuals starting at 14 days after completion of the primary series through the blinded phase for each of the four trials. An analysis of participants living with well-controlled HIV was conducted using the same methods.

RESULTS

3,852/30,351 (12.7%) Moderna participants, 3,088/29,868 (10.3%) Novavax participants, 3,549/32,380 (11.0%) AstraZeneca participants, and 5,047/43,788 (11.5%) Janssen participants were identified as having a TIS. Most TIS conditions (73.9%) were due to metabolism and nutritional disorders. Vaccination (versus placebo) significantly reduced the likelihood of symptomatic and severe COVID-19 for all participants for each trial. VE was not significantly different for TIS participants vs NTIS for either symptomatic or severe COVID-19 for each trial, nor was VE significantly different in the symptomatic endpoint for participants with HIV.

CONCLUSIONS

For individuals with mildly immunocompromising conditions, there is no evidence of differences in VE against symptomatic or severe COVID-19 compared to those with non-tempered immune systems in the four COVID-19 vaccine randomized controlled efficacy trials.

Management of oral herpes simplex virus infections: The problem of resistance. A narrative review

Herpes Simplex Virus (HSV) type 1 (HSV-1) and type 2 (HSV-2) are among the most common human viral pathogens, affecting several billion people worldwide. Although in healthy patients clinical signs and symptoms of HSV infection are usually mild and self-limiting, HSV-infections in immunocompromised patients are frequently more aggressive, persistent, and even life-threatening. Acyclovir and its derivatives are the gold standard antiviral drugs for the prevention and treatment of HSV infections. Although the development of acyclovir resistance is a rather uncommon condition, it may be associated with serious complications, especially in immunocompromised patients. In this review, we aim to address the problem of drug resistant HSV infection and discuss the available alternative therapeutic interventions. All relative studies concerning alternative treatment modalities of acyclovir resistant HSV infection published in PubMed between 1989 to 2022 were reviewed. Long-term treatment and prophylaxis with antiviral agents predisposes to drug resistance, especially in immunocompromised patients. Cidofovir and foscarnet could serve as alternative treatments in these cases. Although rare, acyclovir resistance may be associated with severe complications. Hopefully, in the future, novel antiviral drugs and vaccines will be available in order to avoid the existing drug resistance.

Adenovirus infection in adult patients undergoing allogeneic hematopoietic stem cell transplant: Incidence, clinical management, and outcome

BACKGROUND

Adenovirus infection (ADVi) is an emergent complication in adult patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with poor outcome. Available data on risk factors and optimal management of ADVi in adult allo-HSCT recipients are limited, and recommendations on monitoring and pre-emptive therapy are mainly based on pediatric data.

METHODS

In this single-center, retrospective study, we reported all cases of positive ADV-DNA from adult patients undergoing allo-HSCT in the period 2014-2019. The study aimed to describe the incidence of ADVi at day +180 post-transplant. Secondly to describe timing, clinical presentation, risk factors, and outcome of ADVi and to analyze the application of a screening strategy in our cohort.

RESULTS

In 445 allo-HSCT recipients, the day +180 incidence was: 9% (39/445) for ADVi, 5% (24/445) for ADV viremia (ADVv), and 3% (15/445) for localized ADVi. The median time to ADVi was 65 (IQR 19; 94) days after HSCT. ADVv-related mortality was 13% (3/24), all cases occurring with blood max-ADV-DNA > 10^3 cp/mL. Independent risk factors for ADVi were diagnosis of lymphoproliferative disease (p = .011) and acute graft-versus-host-disease (p = .021).

CONCLUSIONS

In our cohort, ADVi and ADVv were more frequent than previously reported. ADVv with max-ADV-DNA > 10^3 cp/mL was associated with ADV-related mortality, thus careful monitoring and early initiation of treatment are advisable.

Leclercia adecarboxylata in a Patient With Newly Diagnosed Chronic Lymphocytic Leukemia

Leclercia adecarboxylata is a Gram-negative bacillus commonly seen in immunocompromised individuals and often misdiagnosed as Escherichia coli. L. adecarboxylata is an opportunistic pathogen found in aquatic environments. It is a nonfatal infection that has low virulence and endorses susceptibility to many common antibiotics. We report a case of a 53-year-old immunocompromised male who was managed for L. adecarboxylata bacteremia.

Cutaneous squamous cell carcinoma tumor accrual rates in immunosuppressed patients with autoimmune and inflammatory conditions: A retrospective cohort study

BACKGROUND

Immunosuppression is a known risk factor for the development of cutaneous squamous cell carcinoma (CSCC), especially in solid organ transplant recipients and chronic lymphocytic leukemia. However, this risk is less well defined in autoimmune and inflammatory conditions.

OBJECTIVE

Assess the impact that disease-type, duration of immunosuppression, and systemic medications have on CSCC accrual rates, defined as the number of CSCCs a patient develops per year, in autoimmune and inflammatory conditions.

METHODS

Retrospective review of 94 immunosuppressed (rheumatoid arthritis: 31[33.0%], inflammatory bowel disease: 17[18.1%], psoriasis: 11[11.7%], autoimmune other (AO): 24[25.5%], inflammatory other: 21[22.3%]) and 188 immunocompetent controls to identify all primary, invasive CSCCs diagnosed from 2010 to 2020.

RESULTS

Immunosuppressed patients had higher CSCC accrual rates than immunocompetent controls (0.44 ± 0.36): total cohort (0.82 ± 0.95, P < .01), rheumatoid arthritis (0.88 ± 1.10, P < .01), inflammatory bowel disease (0.94 ± 0.88, P < .01), psoriasis (1.06 ± 1.58, P < .01), AO (0.72 ± 0.56, P < .01), and inflammatory other (0.72 ± 0.61, P < .01). There was an association between increased tumor accrual rates and exposure to systemic medications including, immunomodulators, tumor necrosis factor-alpha inhibitors, non-tumor necrosis factor inhibitor biologics, and corticosteroids, but not with number of systemic medication class exposures or duration of immunosuppression.

LIMITATIONS

Retrospective, singlecenter study.

CONCLUSION

Patients with autoimmune and inflammatory conditions accrue CSCCs at higher rates than immunocompetent patients.

Correlation of clinical, laboratory, and short-term outcomes of immunocompromised and immunocompetent COVID-19 patients with semi-quantitative chest CT score findings: A case-control study

BACKGROUND

As the effects of immunosuppression are not still clear on COVID-19 patients, we conducted this study to identify clinical and laboratory findings associated with pulmonary involvement in both immunocompromised and immunocompetent patients.

METHODS

A case-control of 107 immunocompromised and 107 immunocompetent COVID-19 patients matched for age and sex with either positive RT-PCR or clinical-radiological findings suggestive of COVID-19 enrolled in the study. Their initial clinical features, laboratory findings, chest CT scans, and short-term outcomes (hospitalization time and intensive care unit [ICU] admission) were recorded. In addition, pulmonary involvement was assessed with the semi-quantitative scoring system (0-25).

RESULTS

Pulmonary involvement was significantly lower in immunocompromised patients in contrast to immunocompetent patients, especially in RLL (p = 0.001), LUL (p = 0.023), and both central and peripheral (p = 0.002), and peribronchovascular (p = 0.004) sites of lungs. Patchy (p < 0.001), wedged (p = 0.002), confluent (p = 0.002) lesions, and ground glass with consolidation pattern (p < 0.001) were significantly higher among immunocompetent patients. Initial signs and symptoms of immunocompromised patients including dyspnea (p = 0.008) and hemoptysis (p = 0.036), respiratory rate of over 25 (p < 0.001), and spo2 of below 93% (p = 0.01) were associated with higher pulmonary involvement. Total chest CT score was also associated with longer hospitalization (p = 0.016) and ICU admission (p = 0.04) among immunocompromised patients.

CONCLUSIONS

Pulmonary involvement score was not significantly different among immunocompromised and immunocompetent patients. Initial clinical findings (dyspnea, hemoptysis, higher RR, and lower Spo2) of immunocompromised patients could better predict pulmonary involvement than laboratory findings.

Veno-venous ECLS rescue for a heart transplant recipient with COVID-19, a case report

The potential for increased rates of morbidity of SARS-CoV-2 within immunocompromised populations has been of concern since the pandemic's onset. Transplant providers and patients can face particularly challenging situations, in the current settings as data continues to emerge for the prevention and treatment of the immunocompromised subpopulation. This case report details a patient 9-months post orthotopic heart transplant that developed SARS-CoV-2 infection despite two prior doses of the Pfizer-BioNtech COVID-19 vaccine, and had successful rescue from refractory hypoxemia with veno-venous extracorporeal membrane oxygenation (VV ECLS).

A Blast From the Past: Toxoplasmic Encephalitis As the Initial Presentation of HIV/AIDS

Many opportunistic infections (OIs) seen early in the human immunodeficiency virus (HIV) epidemic receded in prevalence with the advent of antiretroviral therapy (ART). Despite the availability of early detection and treatment of HIV as well as guidelines for near-universal screening, there remains a sizable population of individuals living with HIV who are not yet aware of their HIV status. These individuals are at risk for OIs such as toxoplasmosis, which would otherwise be preventable with ART and appropriate prophylaxis. Toxoplasmic encephalitis (TE) usually occurs in the late stages of HIV with acquired immunodeficiency syndrome (AIDS), but we present a case of a 38-year-old female with TE as the initial presentation of HIV/AIDS. Testing for the presence of an immunocompromising condition such as HIV is important in patients presenting with focal brain lesions as the differential diagnosis will change, and proper workup may spare invasive procedures such as a brain biopsy.

Clinical outcomes of baloxavir versus oseltamivir in immunocompromised patients

BACKGROUND

Neuraminidase inhibitors, including oseltamivir, are the treatment standard for influenza. Baloxavir, a novel antiviral, demonstrated comparable outcomes to oseltamivir in outpatients with influenza. Baloxavir was equally effective as oseltamivir in a retrospective study of hospitalized patients with influenza at our institution. However, the efficacy of baloxavir in immunocompromised patients is unclear.

METHODS

We conducted a retrospective cohort study of immunocompromised adult patients hospitalized with influenza A who received baloxavir from January 2019 to April 2019 or oseltamivir from January 2018 to April 2018. Demographic and clinical outcomes were assessed. Primary outcomes were time from antiviral initiation to resolution of hypoxia and fever. Secondary outcomes were length of stay (LOS), intensive care unit (ICU) care, ICU LOS, and 30-day mortality.

RESULTS

Of 95 total patients, 52 received baloxavir and 43 received oseltamivir. Other than younger age (57.5 vs. 65; p = .035) and longer duration between vaccination and symptom onset (114 vs. 86 days; p = .001) in the baloxavir group, baseline characteristics did not differ. H1 was the predominant subtype in the baloxavir group (65.3%) versus H3 in the oseltamivir group (85.7%). When comparing baloxavir to oseltamivir, there was no significant difference in median time from antiviral initiation to resolution of hypoxia (59.9 vs. 42.5 h) and to resolution of fever (21.6 vs. 26.6 h). There were no differences in secondary outcomes.

CONCLUSION

Baloxavir was not associated with longer time to resolution of hypoxia or fever in comparison to oseltamivir. Results must be taken in context of variations in seasonal influenza subtype and resistance rates.

Safety and Immunogenicity of the mRNA-1273 COVID-19 Vaccine in Solid Organ Transplant Recipients

BACKGROUND

Immunosuppressed individuals, including solid organ transplant recipients (SOTRs), are at high risk for severe COVID-19.

METHODS

This open-label, phase 3b trial evaluated mRNA-1273 in 137 adult kidney and 77 liver SOTRs and 20 immunocompetent participants. In Part A, SOTRs received three 100-µg doses of mRNA-1273; immunocompetent participants received 2 doses. In Part B, an additional 100-µg dose was offered ≥4 months post-primary series. Here, we report interim trial results.

RESULTS

mRNA-1273 was well-tolerated in SOTRs. Four serious adverse events were considered vaccine-related by the investigator in 3 SOTRs with pre-existing comorbidities. No vaccine-related biopsy-proven organ rejection events or deaths were reported. mRNA-1273 elicited modest neutralizing antibody (nAb) responses after dose 2 and improved responses after dose 3 in SOTRs. Post-dose 3 responses among liver SOTRs were comparable to post-dose 2 responses in immunocompetent participants. Post-additional dose responses were increased in SOTRs regardless of the primary series vaccination. In liver SOTRs, post-additional dose responses were ∼3-fold higher versus post-dose 2 but were lower than immunocompetent participant responses. Most kidney SOTRs received multiple immunosuppressants and had reduced antibody responses versus liver SOTRs.

CONCLUSIONS

mRNA-1273 (100 µg) was well-tolerated and dose 3 and the additional dose improved antibody responses among SOTRs.

In silico and in vivo evaluation of the anti-cryptosporidial activity of eugenol

Background

Cryptosporidiosis is an opportunistic parasitic disease widely distributed worldwide. Although Cryptosporidium sp. causes asymptomatic infection in healthy people, it may lead to severe illness in immunocompromised individuals. Limited effective therapeutic alternatives are available against cryptosporidiosis in this category of patients. So, there is an urgent need for therapeutic alternatives for cryptosporidiosis. Recently, the potential uses of Eugenol (EUG) have been considered a promising novel treatment for bacterial and parasitic infections. Consequently, it is suggested to investigate the effect of EUG as an option for the treatment of cryptosporidiosis.

Materials and methods

The in silico bioinformatics analysis was used to predict and determine the binding affinities and intermolecular interactions of EUG and Nitazoxanide (NTZ) toward several Cryptosporidium parvum (C. parvum) lowa II target proteins. For animal study, five groups of immunosuppressed Swiss albino mice (10 mice each) were used. Group I was left uninfected (control), and four groups were infected with 1,000 oocysts of Cryptosporidium sp. The first infected group was left untreated. The remaining three infected groups received NTZ, EUG, and EUG + NTZ, respectively, on the 6th day post-infection (dpi). All mice were sacrificed 30 dpi. The efficacy of the used formulas was assessed by counting the number of C. parvum oocysts excreted in stool of infected mice, histopathological examination of the ileum and liver tissues and determination of the expression of iNOS in the ileum of mice in different animal groups.

Results

treatment with EUG resulted in a significant reduction in the number of oocysts secreted in stool when compared to infected untreated mice. In addition, oocyst excretion was significantly reduced in mice received a combination therapy of EUG and NTZ when compared with those received NTZ alone. EUG succeeded in reverting the histopathological alterations induced by Cryptosporidium infection either alone or in combination with NTZ. Moreover, mice received EUG showed marked reduction of the expression of iNOS in ileal tissues.

Conclusion

Based on the results, the present study signified a basis for utilizing EUG as an affordable, safe, and alternative therapy combined with NTZ in the management of cryptosporidiosis.

Clinical and Virological Outcome of Monoclonal Antibody Therapies Across Severe Acute Respiratory Syndrome Coronavirus 2 Variants in 245 Immunocompromised Patients: A Multicenter Prospective Cohort Study

BACKGROUND

Immunocompromised patients (ICPs) have an increased risk for a severe and prolonged COVID-19. SARS-CoV-2 monoclonal antibodies (mAbs) were extensively used in these patients, but data from randomized trials that focus on ICPs are lacking. We evaluated the clinical and virological outcome of COVID-19 in ICPs treated with mAbs across SARS-CoV-2 variants.

METHODS

In this multicenter prospective cohort study, we enrolled B-cell- and/or T-cell-deficient patients treated with casirivimab/imdevimab, sotrovimab, or tixagevimab/cilgavimab. SARS-CoV-2 RNA was quantified and sequenced weekly, and time to viral clearance, viral genome mutations, hospitalization, and death rates were registered.

RESULTS

Two hundred and forty five patients infected with the Delta (50%) or Omicron BA.1, 2, or 5 (50%) variant were enrolled. Sixty-seven percent were vaccinated; 78 treated as outpatients, of whom 2 required hospital admission, but both survived. Of the 159 patients hospitalized at time of treatment, 43 (27%) required mechanical ventilation or died. The median time to viral clearance was 14 days (interquartile range, 7-22); however, it took >30 days in 15%. Resistance-associated spike mutations emerged in 9 patients in whom the median time to viral clearance was 63 days (95% confidence interval, 57-69; P < .001). Spike mutations were observed in 1 of 42 (2.4%) patients after treatment with 2 active mAbs, in 5 of 34 (14.7%) treated with actual monotherapy (sotrovimab), and 3 of 20 (12%) treated with functional monotherapy (ie, tixagevimab/cilgavimab against tixagevimab-resistant variant).

CONCLUSIONS

Despite treatment with mAbs, morbidity and mortality of COVID-19 in ICPs remained substantial. Combination antiviral therapy should be further explored and may be preferred in severely ICPs.

Comparing Molnupiravir to Nirmatrelvir/Ritonavir (Paxlovid) in the Treatment of Mild-to-Moderate COVID-19 in Immunocompromised Cancer Patients

BACKGROUND

Nirmatrelvir/Ritonavir has been shown to reduce the risk of COVID-19 progression by 88% compared to placebo, while Molnupiravir reduced it by 31%. However, these two agents have not been compared head-to-head. We therefore compared the safety and efficacy of both agents for the treatment of mild-to-moderate COVID-19 in immunocompromised cancer patients.

METHODS

We identified 240 cancer patients diagnosed with COVID-19 and treated with Molnupiravir or Nirmatrelvir/Ritonavir. Patients were matched using a 1:2 ratio based on age group (18-64 years vs. ≥65) and type of cancer. The collected data included demographics, comorbidities, and treatment outcome.

RESULTS

Both groups had comparable characteristics and presenting symptoms. However, dyspnea was more prevalent in the Molnupiravir group, while sore throat was more prevalent in the Nirmatrelvir/Ritonavir group. The rate of disease progression was comparable in both groups by univariate and multivariable analysis. Treatment with Molnupiravir versus Nirmatrelvir/Ritonavir revealed no significant difference in disease progression by multivariable analysis (adjusted OR = 1.31, 95% CI: 0.56-3.14, p = 0.70). Patients who received Nirmatrelvir/Ritonavir, however, were significantly more prone to having drug-drug interactions/adverse events (30% vs. 0%, p < 0.0001).

CONCLUSIONS

In the treatment of mild-to-moderate COVID-19 in cancer patients, Molnupiravir was comparable to Nirmatrelvir/Ritonavir in preventing progression to severe disease/death and rebound events, and it had a superior safety profile.

Humoral and cellular immune responses against SARS-CoV-2 post-vaccination in immunocompetent and immunocompromised cancer populations

Cancer patients are at risk for severe coronavirus disease 2019 (COVID-19) outcomes due to impaired immune responses. However, the immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is inadequately characterized in this population. We hypothesized that cancer vs non-cancer individuals would mount less robust humoral and/or cellular vaccine-induced immune SARS-CoV-2 responses. Receptor binding domain (RBD) and SARS-CoV-2 spike protein antibody levels and T-cell responses were assessed in immunocompetent individuals with no underlying disorders (n = 479) and immunocompromised individuals (n = 115). All 594 individuals were vaccinated and of varying COVID-19 statuses (i.e., not known to have been infected, previously infected, or "Long-COVID"). Among immunocompromised individuals, 59% (n = 68) had an underlying hematologic malignancy; of those, 46% (n = 31) of individuals received cancer treatment <30 days prior to study blood collection. Ninety-eight percentage (n = 469) of immunocompetent and 81% (n = 93) of immunocompromised individuals had elevated RBD antibody titers (>1,000 U/mL), and of these, 60% (n = 281) and 44% (n = 41), respectively, also had elevated T-cell responses. Composite T-cell responses were higher in individuals previously infected with SARS-CoV-2 or those diagnosed with Long-COVID compared to uninfected individuals. T-cell responses varied between immunocompetent vs carcinoma (n = 12) cohorts (P < 0.01) but not in immunocompetent vs hematologic malignancy cohorts. Most SARS-CoV-2 vaccinated individuals mounted robust cellular and/or humoral responses, though higher immunogenicity was observed among the immunocompetent compared to cancer populations. The study suggests B-cell targeted therapies suppress antibody responses, but not T-cell responses, to SARS-CoV-2 vaccination. Thus, vaccination continues to be an effective way to induce humoral and cellular immune responses as a likely key preventive measure against infection and/or subsequent more severe adverse outcomes.

IMPORTANCE

The study was prompted by a desire to better assess the immune status of patients among our cancer host cohort, one of the largest in the New York metropolitan region. Hackensack Meridian Health is the largest healthcare system in New Jersey and cared for more than 75,000 coronavirus disease 2019 patients in its hospitals. The John Theurer Cancer Center sees more than 35,000 new cancer patients a year and performs more than 500 hematopoietic stem cell transplants. As a result, the work was undertaken to assess the effectiveness of vaccination in inducing humoral and cellular responses within this demographic.

Atypical pneumonia testing in transplant recipients

BACKGROUND

The incidence of atypical pneumonia among immunocompromised patients is not well characterized. Establishing a diagnosis of atypical pneumonia is challenging as positive tests must be carefully interpreted. We aimed to assess the test positivity rate and incidence of atypical pneumonia in transplant recipients.

METHODS

A retrospective cohort study was conducted at the Yale New Haven Health System in Connecticut. Adults with solid organ transplant, hematopoietic stem cell transplant (HSCT), or chimeric antigen receptor T-cell, who underwent testing for atypical pathogens of pneumonia (Legionella pneumophilia, Mycoplasma pneumoniae, Chlamydia pneumoniae, and Bordetella pertussis) between January 2016 and August 2022 were included. Positive results were adjudicated in a clinical context using pre-defined criteria. A cost analysis of diagnostic testing was performed.

RESULTS

Note that, 1021 unique tests for atypical pathogens of pneumonia were performed among 481 transplant recipients. The testing positivity rate was 0.7% (n = 7). After clinical adjudication, there were three cases of proven Legionella and one case of possible Mycoplasma infection. All cases of legionellosis were in transplant recipients within 1-year post-transplantation with recently augmented immunosuppression and lymphopenia. The possible case of Mycoplasma infection was in an HSCT recipient with augmented immunosuppression. The cost of all tests ordered was $50,797.73.

CONCLUSION

The positivity rate of tests for atypical pneumonia was very low in this transplant cohort. An algorithmic approach that targets testing for those with compatible host, clinical, radiographic, and epidemiologic factors, and provides guidance on test selection and test interpretation, may improve the diagnostic yield and lead to substantial cost savings.

Case series: Stenotrophomonas maltophilia in pediatric oncology patients

BACKGROUND

Stenotrophomonas maltophilia is a bacterial pathogen that can be fatal in hospitalized and immunocompromised patients with mortality as high as 69%. Pediatric cancer patients often have risk factors that are common for this infection, making them particularly susceptible. Managing S. maltophilia is especially challenging as it has inherent resistance to several antibiotics. Furthermore, soft tissue infections in neutropenic patients may deviate from the typical clinical presentation of S. maltophilia.

CASE DETAILS

This case series describes an in-depth examination of three cases involving immunocompromised pediatric patients with S. maltophilia infections. Each case exhibited a distinct clinical presentation, encompassing infection of the blood, lung, and skin, which highlights the variability in which S. maltophilia manifests in immunocompromised pediatric patients. These patients were treated at MD Anderson Cancer Center (MDACC) from 2020 to 2023, unfortunately resulting in fatality.

CONCLUSIONS

The study aims to provide valuable insights and guidance for the management of patients with S. maltophilia infections. Emphasizing a heightened clinical suspicion will potentially lead to early initiation of directed therapy against S. maltophilia. Timely intervention may play a pivotal role in improving patient outcomes and reduce further burden to the healthcare system.

Convalescent Plasma Therapy in Immunocompromised Patients Infected With the BA.1 or BA.2 Omicron SARS-CoV-2

The emergence of SARS-CoV-2 Omicron variant has led to a complete reconfiguration of the therapeutic landscape, with all monoclonal antibodies having lost any neutralization activity. We report here a case series of 75 immunocompromised patients infected by the Omicron variant who benefited from COVID-19 convalescent plasma (CCP). At Day 28, the overall survival was 76% (95% CI 67-86) with no significant difference in the clinical outcome between patients with hematological malignancies, solid organ transplantation or autoimmune diseases. No safety concern was reported during the course of the study. These results showed that CCP is well tolerated and represents a treatment option for immunocompromised patients who remain highly impacted by the COVID19 epidemic.

Progressive multifocal leukoencephalopathy in a lung transplant recipient

Progressive multifocal leukoencephalopathy (PML) is a rare and fatal demyelinating disease of the central nervous system (CNS). The case we describe highlights the importance of considering a diagnosis of PML early (<1 year) after lung transplant.

Neuroinvasive Bacillus cereus Infection in Immunocompromised Hosts: Epidemiologic Investigation of 5 Patients With Acute Myeloid Leukemia

Background

Bacillus cereus is a ubiquitous gram-positive rod-shaped bacterium that can cause sepsis and neuroinvasive disease in patients with acute leukemia or neutropenia.

Methods

A single-center retrospective review was conducted to evaluate patients with acute leukemia, positive blood or cerebrospinal fluid test results for B cereus, and abnormal neuroradiographic findings between January 2018 and October 2022. Infection control practices were observed, environmental samples obtained, a dietary case-control study completed, and whole genome sequencing performed on environmental and clinical Bacillus isolates.

Results

Five patients with B cereus neuroinvasive disease were identified. All patients had acute myeloid leukemia (AML), were receiving induction chemotherapy, and were neutropenic. Neurologic involvement included subarachnoid or intraparenchymal hemorrhage or brain abscess. All patients were treated with ciprofloxacin and survived with limited or no neurologic sequelae. B cereus was identified in 7 of 61 environmental samples and 1 of 19 dietary protein samples-these were unrelated to clinical isolates via sequencing. No point source was identified. Ciprofloxacin was added to the empiric antimicrobial regimen for patients with AML and prolonged or recurrent neutropenic fevers; no new cases were identified in the ensuing year.

Conclusions

B cereus is ubiquitous in the hospital environment, at times leading to clusters with unrelated isolates. Fastidious infection control practices addressing a range of possible exposures are warranted, but their efficacy is unknown and they may not be sufficient to prevent all infections. Thus, including B cereus coverage in empiric regimens for patients with AML and persistent neutropenic fever may limit the morbidity of this pathogen.

"Electronic Phenotyping" Antimicrobials to Facilitate Outpatient Stewardship for Asymptomatic Bacteriuria and Urinary Tract Infection in Renal Transplant

Asymptomatic bacteriuria and urinary tract infection in renal transplant are important antimicrobial stewardship targets but are difficult to identify within electronic medical records. We validated an "electronic phenotype" of antibacterials prescribed for these indications. This may be more useful than billing data in assessing antibiotic indication in this outpatient setting.

Once-Weekly Liposomal Amphotericin B Use for Maintenance and Consolidation Phase Treatment of Cryptococcal Meningitis in Patients With AIDS

Cryptococcal meningitis should be considered in individuals diagnosed with human immunodeficiency virus (HIV) infection and presenting with a cluster of differentiation 4 (CD4)-helper T cell count below 100 cells/ml. The 2022 guidelines from the World Health Organization (WHO) advocate for initiating treatment with a high dose (10 mg/kg) of liposomal amphotericin B, followed by flucytosine and fluconazole for a two-week duration. Additionally, alternative treatment options involving a combination of flucytosine and fluconazole are recommended. Consolidation therapy, as per the WHO guidelines, involves an eight-week course of fluconazole (800 mg), initiated after the induction phase. The dosage is then reduced to 200 mg/day, maintaining this level until the CD4 count exceeds 200 cells/mm3. Notably, the 2022 WHO guidelines prioritize a single dose of liposomal amphotericin B (LampB) over amphotericin B deoxycholate (AmpB-D) at 1 mg/kg due to its association with fewer side effects, including decreased mortality, kidney damage, and anemia. These recommendations are founded on the outcomes of the Ambisome Therapy Induction Optimization (AMBITION-CM), a multicenter, open-label, randomized controlled trial. This case report details the outpatient management of cryptococcal meningitis in a 47-year-old male with acquired immunodeficiency syndrome (AIDS) who exhibited intolerance to fluconazole. In this scenario, the decision to employ liposomal amphotericin B (LampB) as the sole agent for treatment during the outpatient phase was driven by challenges in tolerating fluconazole. Despite the absence of specific research on LampB's standalone use during the maintenance and consolidation phases, concerns regarding the patient's adverse reaction to fluconazole influenced the choice. Notably, LampB's once-weekly infusion schedule, although more expensive than AmpB-D, contributes to enhanced patient compliance. Exploring alternatives to traditional medications, such as interferon-gamma (INF-γ), Mycograb, 18B7, APX001, and T2307, holds promise in targeting novel antigens or complementing existing treatment regimens. Post-discharge, the patient received weekly LampB infusions alongside antiretroviral therapy (ART), resulting in an undetectable viral load and an increased CD4 count. A subsequent cerebrospinal fluid analysis post-discharge revealed a positive India ink stain but negative cultures for Cryptococcus, underscoring the necessity for a comprehensive and adaptable approach in managing cryptococcal meningitis.

Cervical Intramedullary Spinal Cord Abscess Secondary to Discitis and Osteomyelitis in an Immunocompromised Patient

Intramedullary spinal cord abscess is a rare neurological condition, not commonly suspected and often misdiagnosed. Even after a prompt diagnosis and treatment, most patients persist with permanent neurological deficits. In adults, factors such as immunocompromised, intravenous drug use, endocarditis, and sepsis could be associated with its development. In this study, we present the case of a 63-year-old male patient who developed a chronic cervical intramedullary spinal cord abscess after being treated for multiple abscesses in the paravertebral and psoas muscles. A diagnosis of cervical intramedullary spinal cord abscess secondary to osteomyelitis and discitis was made. He underwent a two-stage cervical surgery, with drainage of the abscess, spinal stabilization, and intravenous antibiotics. Although rare, vertebral osteomyelitis and discitis may be related to its development. Early diagnosis, prompt abscess drainage, and appropriate antibiotic therapy are of utmost importance to improve prognosis and minimize the long-term sequelae and complications of permanent neurological deficits.

Cidofovir for Viral Infections in Immunocompromised Children: Guidance on Dosing, Safety, Efficacy, and a Review of the Literature

OBJECTIVE

To describe the use of cidofovir (CDV) for viral infections in immunocompromised children (IC) and provide guidance on dosing and supportive care.

DATA SOURCES

A PubMed search was conducted for literature published between 1997 and January 2022 using the following terms: cidofovir, plus children or pediatrics.

STUDY SELECTION AND DATA EXTRACTION

Limits were set to include human subjects less than 24 years of age receiving intravenous (IV) or intrabladder CDV for treatment of infections due to adenovirus, polyomavirus-BK (BKV), herpesviruses, or cytomegalovirus.

DATA SYNTHESIS

Data were heterogeneous, with largely uncontrolled studies. Conventional dosing (CDV 5 mg/kg/dose weekly) was commonly used in 60% (31/52) of studies and modified dosing (CDV 1 mg/kg/dose 3 times/week) was used in 17% (9/52) of studies, despite being off-label. Nephrotoxicity reported across studies totaled 16% (65/403 patients), which was higher for conventional dosing 29 of 196 patients (15%) than modified dosing 1 of 27 patients (4%). Saline hyperhydration and concomitant probenecid remain the cornerstones of supportive care, while some regimens omitting probenecid are emerging to target BKV.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

To our knowledge, this is the first comprehensive review of CDV use (indications, dosing, supportive care, response, and nephrotoxicity) in pediatric IC.

CONCLUSIONS

Effective utilization of CDV in IC remains challenging. Further prospective studies are needed to determine the optimal CDV dosing; however, less aggressive dosing regimens such as modified thrice weekly dosing or low dosing once weekly omitting probenecid to enhance urinary penetration may be reasonable alternatives to conventional dosing in some IC.

[Clinical courses and costs for hospitalizations of potentially immunocompromised COVID-19 patients in Germany]

BACKGROUND

 Patients at increased risk of inadequate immune response to COVID-19 vaccinations due to their underlying disease or therapy are potentially vulnerable to severe COVID-19 courses. The aim is to assess the population size, clinical courses and hospitalization costs of these patients in Germany.

METHODS

 This retrospective cohort study is based on extrapolations of a representative sample of statutory health insurance (SHI) claims data from 2020. Clinical COVID-19 courses, hospitalization costs and durations are compared between the insured group at increased risk for inadequate immune response to COVID-19 vaccinations (risk group) and the insured group without this risk.

RESULTS

 There are approximately 1.82 million SHI-insured individuals in the risk group, of whom an estimated 240 000 insured individuals do not develop a humoral immune response after 3 COVID-19 vaccinations. The risk group shows higher proportions with COVID-19 (relative risk [RR] 1.21; 95 % confidence interval [95 % CI] 1.20-1.23), hospitalizations for COVID-19 (RR 3.40; 95 % CI 3.33-3.48), hospitalizations for COVID-19 with intensive care treatment (RR 1.36; 95 % CI 1.30-1.42), and mortality (RR 5.14; 95 % CI 4.97-5.33) compared with the group without risk. In addition, hospitalizations in the risk group are on average 18 % longer (15.36 days vs. 13.00 days) and 19 % more expensive (12 371 € vs. 10 410 €). Expected hospitalization costs in the risk group are four times greater than in the group without risk (4115 € vs. 1017 €).

CONCLUSIONS

 The risk group is vulnerable to COVID-19 and requires additional resources in the German hospital sector. This results in a need for further protective measures. Further studies are needed to evaluate the impact of different viral variants, active and passive immunizations, and therapies on clinical COVID-19 courses and their costs.

The effect of molnupiravir and nirmatrelvir on SARS-CoV-2 genome diversity in infected and immune suppressed mice

Objectives

Immunocompromised individuals are susceptible to severe COVID-19 and potentially contribute to the emergence of variants with altered pathogenicity due to persistent infection. This study investigated the impact of immunosuppression on SARS-CoV-2 infection in k18-hACE2 mice and the effectiveness of antiviral treatments in this context.

Methods

Mice were immunosuppressed using cyclophosphamide and infected with a B lineage of SARS-CoV-2. Molnupiravir and nirmatrelvir, alone and in combination, were administered and viral load and viral sequence diversity was assessed.

Results

Treatment of infected but immune compromised mice with both compounds either singly or in combination resulted in decreased viral loads and pathological changes compared to untreated animals. Treatment also abrogated infection of neuronal tissue. However, no consistent changes in the viral consensus sequence were observed, except for the emergence of the S:H655Y mutation. Molnupiravir, but not nirmatrelvir or immunosuppression alone, increased the transition/transversion (Ts/Tv) ratio, representative of A>G and C>U mutations and this increase was not altered by the co-administration of nirmatrelvir with molnupiravir.Notably, immunosuppression itself did not appear to promote the emergence of mutational characteristic of variants of concern (VOCs).

Conclusions

Further investigations are warranted to fully understand the role of immunocompromised individuals in VOC development and to inform optimised public health strategies. It is more likely that immunodeficiency promotes viral persistence but does not necessarily lead to substantial consensus-level changes in the absence of antiviral selection pressure. Consistent with mechanisms of action, molnupiravir showed a stronger mutagenic effect than nirmatrelvir in this model.

Efficacy of Palivizumab Immunoprophylaxis for Reducing Severe RSV Outcomes in Children with Immunodeficiencies: A Systematic Review

BACKGROUND

Palivizumab is recommended for prevention of severe respiratory syncytial virus (RSV) disease in immunocompromised children, despite a lack of strong supporting evidence. The recent approval of substitute RSV-neutralizing monoclonal antibodies against RSV, offers an opportunity to synthesize the most current evidence supporting the palivizumab standard of care.

OBJECTIVE

To evaluate the efficacy of palivizumab in preventing acute respiratory tract infection- or RSV-related hospitalization, or mortality in immunocompromised children.

METHODS

We searched Ovid MEDLINE and EMBASE for published clinical studies that investigated outcomes of palivizumab use in children. We included clinical trials, cohort studies, and case-control studies. The primary outcomes were RSV-related or respiratory viral infection-related hospitalizations, or RSV-related mortality. This systematic review was registered in PROSPERO (ID CRD42021248619) and is reported in accordance with the PRISMA guidelines.

RESULTS

From the 1993 records, six studies were eligible and included, for a total of 625 immunocompromised children with an heterogeneous composition of primary and acquired immunodeficiencies enrolled from palivizumab programs. There were no intervention studies. None of the studies included a control group. RSV hospitalizations were infrequent (0%-3.1% of children). Most children included received palivizumab, although one study (n = 56) did not specify how many received palivizumab. RSV mortality was neither observed, in three studies, nor reported, in three other studies.

CONCLUSIONS

The evidence supporting the use of palivizumab for prevention of severe RSV disease in immunocompromised children remains extremely limited and appears insufficient to justify prioritizing this intervention as the current standard of care over alternative interventions.

Changes in antibody titer after four and five doses of the SARS-CoV-2 vaccine in Japanese post-kidney transplant patients

INTRODUCTION

Immunosuppressed patients exhibit low antibody acquisition rates following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Kidney transplant recipients previously exhibited low antibody acquisition rates after two vaccine doses, which increased after the third dose. We evaluated antibody titers of Japanese post-kidney transplant patients after the fourth and fifth vaccinations.

METHODS

Antibody titers for SARS-CoV-2 spike protein were measured between 3 weeks and 3 months after the fourth or fifth vaccination.

RESULTS

Increased antibody acquisition rates were observed after the fourth (75.0% antibody-positive) and fifth (81.5% antibody-positive) vaccinations. The antibody-acquired group after the fourth vaccination exhibited a higher body mass index and estimated glomerular filtration rate (eGFR) than the non-acquired group. A higher eGFR was associated with antibody acquisition after the fifth vaccination.

CONCLUSION

In Japanese post-kidney transplant patients, the antibody acquisition rate increased with each vaccine additional dose. Additional vaccinations are recommended to protect against SARS-CoV-2 infection.

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.

Nirmatrelvir Resistance-de Novo E166V/L50V Mutations in an Immunocompromised Patient Treated With Prolonged Nirmatrelvir/Ritonavir Monotherapy Leading to Clinical and Virological Treatment Failure-a Case Report

Resistance of SARS-CoV-2 to antivirals was shown to develop in immunocompromised individuals receiving remdesivir. We describe an immunocompromised patient who was treated with repeated and prolonged courses of nirmatrelvir and developed de-novo E166V/L50F mutations in the Mpro region. These mutations were associated with clinical and virological treatment failure.

Adaptation of Chagas Disease Screening Recommendations for a Community of At-risk HIV in the United States

Chagas disease (CD), caused by Trypanosoma cruzi, is underdiagnosed in the United States. Improved screening strategies are needed, particularly for people at risk for life-threatening sequelae of CD, including people with human immunodeficiency virus (HIV, PWH). Here we report results of a CD screening strategy applied at a large HIV clinic serving an at-risk population.

High Burden of COVID-19-Associated Pulmonary Aspergillosis in Severely Immunocompromised Patients Requiring Mechanical Ventilation

BACKGROUND

Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is a frequent superinfection in critically ill patients with COVID-19 and is associated with increased mortality rates. The increasing proportion of severely immunocompromised patients with COVID-19 who require mechanical ventilation warrants research into the incidence and impact of CAPA during the vaccination era.

METHODS

We performed a retrospective, monocentric, observational study. We collected data from adult patients with severe COVID-19 requiring mechanical ventilation who were admitted to the intensive care unit (ICU) of University Hospitals Leuven, a tertiary referral center, between 1 March 2020 and 14 November 2022. Probable or proven CAPA was diagnosed according to the 2020 European Confederation for Medical Mycology/International Society for Human and Animal Mycology (ECMM/ISHAM) criteria.

RESULTS

We included 335 patients. Bronchoalveolar lavage sampling was performed in 300 (90%), and CAPA was diagnosed in 112 (33%). The incidence of CAPA was 62% (50 of 81 patients) in European Organisation for Research and Treatment of Cancer (EORTC)/Mycosis Study Group Education and Research Consortium (MSGERC) host factor-positive patients, compared with 24% (62 of 254) in host factor-negative patients. The incidence of CAPA was significantly higher in the vaccination era, increasing from 24% (57 of 241) in patients admitted to the ICU before October 2021 to 59% (55 of 94) in those admitted since then. Both EORTC/MSGERC host factors and ICU admission in the vaccination era were independently associated with CAPA development. CAPA remained an independent risk factor associated with mortality risk during the vaccination era.

CONCLUSIONS

The presence of EORTC/MSGERC host factors for invasive mold disease is associated with increased CAPA incidence and worse outcome parameters, and it is the main driver for the significantly higher incidence of CAPA in the vaccination era. Our findings warrant investigation of antifungal prophylaxis in critically ill patients with COVID-19.

Point of care thoracic ultrasound versus chest computed tomography in the approach of febrile neutropenia patients: A diagnostic accuracy cohort study

Single-center prospective cohort diagnostic accuracy study. Our study aimed to evaluate the accuracy and reproducibility of Thoracic Ultrasound (TUS) in detecting pulmonary pathology in immunosuppressed patients. We conducted a single-center prospective study. Consecutive patients with febrile neutropenia who underwent CT (Computerized Tomography) underwent TUS evaluation within 24h of CT. Both studies were performed by an expert who was blinded to the clinical information and results of the alternative imaging modalities. 34 patients met the inclusion criteria. The median age was 39.9 years (±17 standard deviation). TUS as a diagnostic test had a sensitivity of 92.9% and specificity of 83.3%, negative predictive value of 71.4%, and positive predictive value of 96.3%. Substantial between-method agreement was demonstrated with a kappa of 0.71 (P = .001) between the TUS and chest CT findings. We obtained a kappa of 1 (P = .001) for the final diagnosis of Pleural Effusion (PE). We concluded that TUS is a promising screening test for immunocompromised individuals. The results showed good diagnostic performance of TUS compared to CT for the detection of pulmonary findings highly suggestive of pathology with high accuracy and reproducibility.

Serial Quantitation of Plasma Microbial Cell-Free DNA Before and After Diagnosis of Pulmonary Invasive Mold Infections After Hematopoietic Cell Transplant

BACKGROUND

Plasma microbial cell-free DNA sequencing (mcfDNA-Seq) is a noninvasive test for microbial diagnosis of invasive mold infection (IMI). The utility of mcfDNA-Seq for predicting IMI onset and the clinical implications of mcfDNA concentrations are unknown.

METHODS

We retrospectively tested plasma from hematopoietic cell transplant (HCT) recipients with pulmonary IMI and ≥1 mold identified by mcfDNA-Seq in plasma collected within 14 days of clinical diagnosis. Samples collected from up to 4 weeks before and 4 weeks after IMI diagnosis were evaluated using mcfDNA-Seq.

RESULTS

Thirty-five HCT recipients with 39 IMIs (16 Aspergillus and 23 non-Aspergillus infections) were included. Pathogenic molds were detected in 38%, 26%, 11%, and 0% of samples collected during the first, second, third, and fourth week before clinical diagnosis, respectively. In non-Aspergillus infections, median mcfDNA concentrations in samples collected within 3 days of clinical diagnosis were higher in infections with versus without extrapulmonary spread (4.3 vs 3.3 log10 molecules per microliter [mpm], P = .02), and all patients (8/8) with mcfDNA concentrations >4.0 log10 mpm died within 42 days after clinical diagnosis.

CONCLUSIONS

Plasma mcfDNA-Seq can identify pathogenic molds up to 3 weeks before clinical diagnosis of pulmonary IMI. Plasma mcfDNA concentrations may correlate with extrapulmonary spread and mortality in non-Aspergillus IMI.

Within-Host Rhinovirus Evolution in Upper and Lower Respiratory Tract Highlights Capsid Variability and Mutation-Independent Compartmentalization

BACKGROUND

Rhinovirus (RV) infections can progress from the upper (URT) to lower (LRT) respiratory tract in immunocompromised individuals, causing high rates of fatal pneumonia. Little is known about how RV evolves within hosts during infection.

METHODS

We sequenced RV complete genomes from 12 hematopoietic cell transplant patients with infection for up to 190 days from both URT (nasal wash, NW) and LRT (bronchoalveolar lavage, BAL). Metagenomic and amplicon next-generation sequencing were used to track the emergence and evolution of intrahost single nucleotide variants (iSNVs).

RESULTS

Identical RV intrahost populations in matched NW and BAL specimens indicated no genetic adaptation is required for RV to progress from URT to LRT. Coding iSNVs were 2.3-fold more prevalent in capsid over nonstructural genes. iSNVs modeled were significantly more likely to be found in capsid surface residues, but were not preferentially located in known RV-neutralizing antibody epitopes. Newly emergent, genotype-matched iSNV haplotypes from immunocompromised individuals in 2008-2010 could be detected in Seattle-area community RV sequences in 2020-2021.

CONCLUSIONS

RV infections in immunocompromised hosts can progress from URT to LRT with no specific evolutionary requirement. Capsid proteins carry the highest variability and emergent mutations can be detected in other, including future, RV sequences.

Combined antiviral therapy as effective and feasible option in allogenic hematopoietic stem cell transplantation during SARS-COV-2 infection: a case report

Here we describe the case of a 51 years old Italian woman with acute lymphoblastic leukemia who underwent to hematopoietic stem cell transplantation (HSCT) during SARS-COV-2 infection. She presented a prolonged COVID-19 successfully treated with dual anti SARS-COV-2 antiviral plus monoclonal antibody therapy.

Viral meningoencephalitis in pediatric solid organ or hematopoietic cell transplant recipients: a diagnostic and therapeutic approach

Neurologic complications, both infectious and non-infectious, are frequent among hematopoietic cell transplant (HCT) and solid organ transplant (SOT) recipients. Up to 46% of HCT and 50% of SOT recipients experience a neurological complication, including cerebrovascular accidents, drug toxicities, as well as infections. Defects in innate, adaptive, and humoral immune function among transplant recipients predispose to opportunistic infections, including central nervous system (CNS) disease. CNS infections remain uncommon overall amongst HCT and SOT recipients, compromising approximately 1% of total cases among adult patients. Given the relatively lower number of pediatric transplant recipients, the incidence of CNS disease amongst in this population remains unknown. Although infections comprise a small percentage of the neurological complications that occur post-transplant, the associated morbidity and mortality in an immunosuppressed state makes it imperative to promptly evaluate and aggressively treat a pediatric transplant patient with suspicion for viral meningoencephalitis. This manuscript guides the reader through a broad infectious and non-infectious diagnostic differential in a transplant recipient presenting with altered mentation and fever and thereafter, elaborates on diagnostics and management of viral meningoencephalitis. Hypothetical SOT and HCT patient cases have also been constructed to illustrate the diagnostic and management process in select viral etiologies. Given the unique risk for various opportunistic viral infections resulting in CNS disease among transplant recipients, the manuscript will provide a contemporary review of the epidemiology, risk factors, diagnosis, and management of viral meningoencephalitis in these patients.

Clinician perceptions of research priorities for the management of noncritically ill patients admitted to hospital with SARS-CoV-2 infection

The changing phenotype of coronarvirus disease 2019 (COVID-19) may quickly render guideline-recommended interventions obsolete. We developed a 40-question clinician survey in consultation with the Australasian COVID-19 Trial site investigators. The survey was designed to assess clinician perceptions of the current treatment strategies and future research priorities in the management of non-critically ill patients admitted to hospital with SARS-CoV-2 infection. There were 84 complete responses from predominantly Australian and New Zealand clinicians. The perceived prevalence of patients with incidental COVID-19, nosocomial infection, underlying illness exacerbated by COVID-19, and/or immunocompromised status suggests new populations to target. The results highlighted clinician interest in antiviral therapies for future research in both immunocompetent and immunocompromised cohorts. These survey results underscore the need for ongoing surveillance of COVID-19 disease phenotypes and clinician and patient priorities for future research.

Disseminated Nocardia farcinica Infection in a Renal Transplant Patient: A Case Report

Nocardia farcinica, an aerobic, Gram-positive bacterium belonging to the genus Nocardia, is a challenging opportunistic pathogen, particularly impacting immunocompromised individuals. The prevalence of human disease has witnessed a notable rise over the past two decades, correlating with an expanding population of immunocompromised individuals and advancements in the detection and identification of Nocardia spp. within clinical laboratories. This case is of a 59-year-old male with compromised immunity due to immunosuppressive medication use following a renal transplant who had an array of presentations before confirming a diagnosis of disseminated nocardiosis. The challenges faced in our case provide valuable insights into the complexities associated with diagnosing and managing Nocardia infections in immunocompromised populations, informing future clinical practice and research endeavors.