Invasive pneumococcal disease among adults with hematological and solid organ malignancies: A population-based cohort study

Changes in vaccination uptake against pneumococcal disease, influenza, and coronavirus disease 2019 (COVID-19) before and after a Head and Neck cancer diagnosis

BACKGROUND

Pneumonia is one of the main contributors to non-cancer mortality among patients with head and neck cancer (HNC). This study aimed to determine the vaccine uptake for pneumococcal polysaccharide and conjugate vaccines, quadrivalent influenza vaccines, and mRNA COVID-19 vaccines before and after an HNC diagnosis. Furthermore, the study investigated the timing of vaccination after a cancer diagnosis.

MATERIALS & METHODS

This register based multicentre study included Danish patients ≥ 18y diagnosed with HNC between 2018 and 2021. The vaccine uptake was assessed by calculating cumulative incidence (CI), while the timing of vaccination after an HNC diagnosis was explored by calculating incidence rates of vaccination the first and second half year after a cancer diagnosis.

RESULTS

The cumulative incidence of vaccine uptake for pneumococcal vaccines was estimated to be 8 % and 16 % one year before and after an HNC diagnosis, respectively. The CIs were 36 % and 38 % for quadrivalent influenza vaccines, respectively, whereas the CIs of vaccine uptake for mRNA COVID-19 vaccines were 60 % and 89 %. The IR of mRNA COVID-19 vaccinations the first half year after HNC diagnosis were 273 per 1000 person-months of follow-up (PMFU) and 111 per 1000 PMFU the second half year, respectively (IRR: 0.38, p < 0.001). Comparing the same periods, the IR of quadrivalent influenza vaccination was 28 per 1000 PMFU and 51 per 1000 PMFU (IRR: 1.95, 0 < 0.001). The IRs of pneumococcal vaccinations were 11 per 1000 PMFU and 14 per 1000 PMFU (IRR 1.28, p = 0.21).

CONCLUSIONS

Although our study shows a significant increase in pneumococcal and COVID-19 vaccine uptake after HNC diagnosis, a gap remains in vaccine uptake before diagnosis, underscoring the need for increased awareness of vaccination options and recommendations. Our findings could serve as a reference for future recommendations.

Management of vaccinations in patients with non-Hodgkin lymphoma

Vaccinations are fundamental tools in preventing infectious diseases, especially in immunocompromised patients like those affected by non-Hodgkin lymphomas (NHLs). The COVID-19 pandemic made clinicians increasingly aware of the importance of vaccinations in preventing potential life-threatening SARS-CoV-2-related complications in NHL patients. However, several studies have confirmed a significant reduction in vaccine-induced immune responses after anti-CD20 monoclonal antibody treatment, thus underscoring the need for refined immunization strategies in NHL patients. In this review, we summarize the existing data about COVID-19 and other vaccine's efficacy in patients with NHL and propose multidisciplinary team-based recommendations for the management of vaccines in this specific group of patients.

Immunogenicity of the 13-Valent Pneumococcal Conjugated Vaccine Followed by the 23-Valent Polysaccharide Vaccine in Chronic Lymphocytic Leukemia

Patients with Chronic Lymphocytic Leukemia (CLL) have a 29- to 36-fold increased risk of invasive pneumococcal disease (IPD) compared to healthy adults. Therefore, most guidelines recommend vaccination with the 13-valent pneumococcal conjugated vaccine (PCV13) followed 2 months later by the 23-valent polysaccharide vaccine (PPSV23). Because both CLL as well as immunosuppressive treatment have been identified as major determinants of immunogenicity, we aimed to assess the vaccination schedule in untreated and treated CLL patients. We quantified pneumococcal IgG concentrations against five serotypes shared across both vaccines, and against four serotypes unique to PPSV23, before and eight weeks after vaccination. In this retrospective cohort study, we included 143 CLL patients, either treated (n = 38) or naive to treatment (n = 105). While antibody concentrations increased significantly after vaccination, the overall serologic response was low (10.5%), defined as a ≥4-fold antibody increase against ≥70% of the measured serotypes, and significantly influenced by treatment status and prior lymphocyte number. The serologic protection rate, defined as an antibody concentration of ≥1.3 µg/mL for ≥70% of serotypes, was 13% in untreated and 3% in treated CLL patients. Future research should focus on vaccine regimens with a higher immunogenic potential, such as multi-dose schedules with higher-valent T cell dependent conjugated vaccines.

Missed Opportunities? A retrospective study into adults hospitalized with invasive infection from airway pathogens

Background

Invasive disease caused by airway pathogens, including Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Moraxella catarrhalis, has high morbidity and mortality worldwide, with immunodeficiency being a known association with recurrent disease. The study aimed to describe the frequency of known immunodeficiency and predisposing factors in adult patients presenting with invasive infections and determine the frequency of screening for and detection of immunodeficiency.

Methods

A retrospective analysis was conducted at a large tertiary Australian health service, comprising multiple centers. Patients aged 18 years or older, in whom the above pathogens were isolated from sterile sites, were included as identified through a microbiology database, between 2015 and 2020. Using electronic medical records, patient demographics, medical history, outcomes of admission, and pathology results were captured and reviewed to address the aims.

Results

In 252 patients, S pneumoniae was the most common culprit, isolated in 73% (185/252), compared to 14.3% (36/252) and 11.5% (29/252) of infections caused by H influenzae and N meningitidis, respectively. Known diagnoses of secondary immunodeficiency were common (31% of patients). Of those presenting with invasive pneumococcal disease, 78% had at least 1 predisposing condition, though only 9 patients (6%) had previously received pneumococcal vaccination. Despite poor screening for immunodeficiency, 12 new diagnoses were made. While the commonest immunodeficiency was secondary, due to hematological and solid organ malignancies, 3 new primary immunodeficiency diagnoses were made.

Conclusions

Immunodeficiency is common in this patient population. Screening should be undertaken to ensure timely diagnosis and treatment of the underlying condition to avoid future morbidity and mortality.

Immunogenicity of a 5-dose pneumococcal vaccination schedule following allogeneic hematopoietic stem cell transplantation

The optimal schedule of pneumococcal vaccination after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) remains controversial. The objective of this study was to investigate the immunogenicity of a 5‐dose pneumococcal vaccination schedule in adult allo‐HSCT recipients with and without immunosuppressive therapy. In this prospective cohort study, allo‐HSCT recipients received four doses of the 13‐valent pneumococcal conjugate vaccine (PCV13) and one dose of the 23‐valent pneumococcal polysaccharide vaccine (PPSV23) starting 4–6 months after allo‐HSCT. PCV13 was administered at T0, T1, T2, and T8 (T = months from enrollment) and PPSV23 at T10. Serum was collected at T0, T4, T8, T10, and T12, and IgG levels were measured for all 24 vaccine serotypes by immunoassay. The primary outcome was overall seroprotection at T12 defined as an IgG concentration ≥1.3 μg/ml for 17/24 vaccine serotypes in allo‐HCST recipients with and without immunosuppressive therapy at baseline. Secondary outcomes were serotype‐specific seroprotection and dynamics of IgG levels. We included 89 allo‐HSCT recipients in the final analysis. Overall seroprotection was 47% (15/32) for patients without immunosuppressive therapy at baseline versus 24% (11/46) for patients with immunosuppressive therapy (p = .03). Seroprotection was higher for PCV13 serotypes (78% and 54% respectively; p = .03) and lower for PPSV23‐unique serotypes (28% and 13% respectively; p = .1). IgG concentrations increased significantly over time for all 24 serotypes. Concluding, although immunogenicity of PCV13 serotypes was reasonable, the poor response to PPSV23 serotypes resulted in an insufficient overall response to pneumococcal vaccination for allo‐HSCT recipients. Research into vaccination strategies with higher‐valent T‐cell‐dependent pneumococcal vaccines is needed.

Incidence and Predictors of Community-Acquired Pneumonia in Patients With Hematological Cancers Between 2016 and 2019

Background

Patients with hematological cancers (HC) are at high risk of infections, in particular community-acquired pneumonia (CAP). Recent data on incidence and predictors of CAP among patients with HC are scarce.

Methods

We performed a cohort study (2016–2019) in 2 hospitals in the Netherlands among adults with HC to calculate incidence rates (IRs) of CAP. In addition, we performed a nested case-control study to identify predictors of CAP.

Results

We identified 275 CAP cases during 6264 patient-years of follow-up. The IR of CAP was 4390/100 000 patient-years of follow-up. Compared with the general population, IR ratios ranged from 5.4 to 55.3 for the different HCs. The case fatality and intensive care unit (ICU) admission rates were 5.5% and 9.8%, respectively. Predictors for CAP in patients with HC were male sex, anemia, lymphocytopenia, chronic kidney disease, cardiovascular disease, autologous and allogeneic stem cell transplantation, treatment with immunosuppressive medication for graft-vs-host disease, treatment with rituximab in the past year, and treatment with immunomodulators (lenalidomide, thalidomide, pomalidomide and/or methotrexate) in the past month. Independent predictors of a severe disease course (death or ICU admission) included neutropenia (odds ratio, 4.14 [95% confidence interval, 1.63–10.2]), pneumococcal pneumonia (10.24 [3.48–30.1]), chronic obstructive pulmonary disease (6.90 [2.07–23.0]), and the use of antibacterial prophylaxis (2.53 [1.05–6.08]).

Conclusions

The burden of CAP in patients with HC is high, with significant morbidity and mortality rates. Therefore, vaccination against respiratory pathogens early in the disease course is recommended, in particular before starting certain immunosuppressive therapies.

The Risk of Invasive Pneumococcal Disease Differs between Risk Groups in Norway Following Widespread Use of the 13-Valent Pneumococcal Vaccine in Children

The elderly and adults with medical risk conditions remain at high risk of invasive pneumococcal disease (IPD), highlighting the importance of adequate preventive efforts. In an observational population-based study in Norway (pop ≥ 5 years, 2009-2017) covering six years post-PCV13 implementation, we explored the incidence and risk of IPD associated with age and comorbidities. We obtained the data on 5535 IPD cases from the Norwegian Surveillance System for Communicable Diseases and the population data from Statistics Norway. To define comorbidities, we obtained ICD-10 codes from the Norwegian Patient Registry for the cases and the Norwegian population. The average annual decrease in PCV13 IPD incidence was significant in all risk groups and decreased post-PCV13 introduction by 16-20% per risk group, implying a nondifferential indirect protection from the childhood vaccination. The IPD incidence remained high in the medical risk groups. The relative importance of medical risk conditions was 2.8 to 6 times higher in those aged 5-64 versus ≥65 years for all types of IPD, since age itself is a risk factor for IPD. In groups without medical risk, the risk of IPD was eight times higher in those aged ≥65 compared to those 5-64 years (RR 8.3 (95% CI 7.3-9.5)). Our results underscore the need for age- and risk-group-based prevention strategies.