Leszek Szenborn

Patients undergoing cardiac surgery are particularly vulnerable to infectious diseases, which may adversely affect perioperative outcomes and long-term prognosis both before and after the procedure. Moreover, those requiring heart transplantation must take immunosuppressive medications, further compromising their immunity. This narrative review aims to look for the sources of increased risk for infections as well as synthesize vaccination recommendations for these patient groups based on the available literature and guidelines. We considered the influence of age, comorbidities, length of hospitalization, procedure-related risks, and blood product transfusions on the increased risk of vaccine-preventable diseases. By comprehensively addressing these factors, healthcare providers can develop tailored vaccination strategies that maximize protection for cardiac surgical patients while minimizing potential complications and optimizing overall health outcomes.

Background/Objectives: Booster vaccination coverage in the adult population in Poland remains insufficient. The objective of this study was to utilize the opportunity of a visit to the Regional Blood Transfusion Center in Wroclaw—associated with blood donation—as a means to remind individuals about the need for tetanus booster vaccination and to assess tetanus immunity in healthy adults (30–40 years after their last mandatory dose) who had not received booster immunizations. Materials and Methods: A total of 97 blood donors aged 50 to 64 years (median age: 54 years) were enrolled, of whom 78% were male. 1. Tetanus immunity was assessed by a single measurement of serum anti-tetanus IgG antibody concentration. 2. A questionnaire was used to collect data relevant to tetanus immune status. 3. Individuals with insufficient protection received a booster dose of the tetanus vaccine, and the post-vaccination serologic response was evaluated. Results: 1. In the study group, 10.3% of participants had no protective immunity against Clostridium tetani, while 5.2% exhibited uncertain protection. An additional 32% demonstrated antibody levels conferring only short-term protection. Satisfactory protection—defined as immunity lasting at least 3 years—or long-term protection (at least 5 years) was identified in 52.5% of patients. Although 72% of donors reported receiving mandatory childhood immunizations, only 5% could provide medical documentation. In this subgroup, a significantly higher geometric mean antibody concentration was observed (0.69 vs. 0.52 IU/mL; p = 0.04), and significantly fewer participants required immediate post-exposure prophylaxis (1/39 vs. 14/54; p = 0.003). 2. Among the 46 individuals eligible for a booster dose, 17 (37%) returned for vaccination. Of these, 16 (94%) achieved antibody titers consistent with long-term protection following a single vaccine dose. Conclusions: Tetanus immunity among adults is heterogeneous and difficult to predict due to the frequent lack of vaccination records and unreliable self-reported histories. A history of injury and associated surgical wound care involving injection often serves as the only indication of prior vaccination. A single booster dose is highly effective in eliciting a robust immune response in individuals vaccinated during childhood but lacking recent boosters. Rising vaccine hesitancy toward both mandatory and recommended immunizations in Poland negatively influences adult decisions regarding tetanus vaccination. Participation in voluntary blood donation programs presents a valuable opportunity for immunization education, immune status screening, and the implementation of effective catch-up vaccination strategies.

Introduction: Staphylococci commonly colonise the skin and mucous membranes of humans and animals, the close contact between which may promote interspecies transmission of these microorganisms and determinants of drug resistance. Material and Methods: Material collected from animals (n = 274) and humans (n = 261) between 2019 and 2023 was studied. Samples were swabbed from six anatomical sites of each pet: the external ear canal, conjunctival sacs, nares, oral cavity, groin skin and anus. Swabs were taken from four places of each human: the vestibule of the nasal cavity, the throat near the tonsils, and the skin behind the auricle and in the elbow bend. The pets’ owners and the human participants completed a questionnaire about the study subject and the subject’s living environment to elucidate risk factors associated with staphylococci colonisation. Results: The prevalence of Staphylococcus aureus was 12.42% in cats and 8.85% in dogs, while S. pseudintermedius was isolated from 5.59% of cats and 58.41% of dogs. Of the people, 38.7% were carriers of S. aureus and 2.68% carriers of S. pseudintermedius . A total of 202 S. aureus strains and 165 S. pseudintermedius strains were analysed. Drug resistance was tested in disc diffusion and resistance genes were detected by PCR. The most frequent resistance of S.aureus was to ampicillin (62.4%), penicillin (61.4%) and erythromycin (29.2%), while S. pseudintermedius was mostly resistant to penicillin (71.5%), ampicillin (63.6%) and clindamycin and erythromycin (41.2% in both cases). Methicillin resistance was found in 4.5% of S. aureus and 12.1% of S. pseudintermedius isolates. The most common S. aureus resistance genes were blaZ (79.7%), tet [M] (53.1%) and ermA (29.7%) and the S. pseudintermedius pattern was of blaZ (84.2%), tet [M] (53.3%) and ermB (38.2%). Regarding risk factors, animals from non-commercial sources had 11-fold higher methicillin resistance than those from commercial breeders, dogs had 50-fold lower risk than humans, and recent antibiotic treatment also increased resistance. Conclusion: Monitoring the epidemiology of strains and knowing the prevalence of resistant isolates can shape preventive programmes in both veterinary and human medicine, inform appropriate therapeutic decisions and combat the phenomenon of drug resistance.

A 16-year-old boy was admitted to a district hospital with fever, headaches, abdominal pain, vomiting, and heart murmur. Thickening of the mitral valve leaflet with regurgitation was diagnosed by a cardiologist, who, suspecting infective endocarditis, referred the patient to a specialist centre. The diagnosis was confirmed by blood cultures showing infection with a non-toxigenic species of Corynebacterium diphtheriae. Antibiotic treatment was continued. The boy was urgently referred to cardiac surgery to remove the affected mitral valve and implant a St. Jude 31 mm mechanical prosthesis. The postoperative course was uncomplicated, and after 8 days he was transferred to the Department of Cardiology, where treatment with antibiotics and anticoagulants was continued, maintaining the international normalised ratio of 2.5–3. He was discharged home in good condition with the recommendation to continue antibiotic therapy for another three weeks, monitor inflammatory markers, as well as continue cardiac medications and anticoagulants. Conclusion – Corynebacterium diphtheriae can cause endocarditis.

Background: Multisystem inflammatory syndrome in children (MIS-C) is a rare, severe complication of coronavirus disease 2019, commonly involving the gastrointestinal tract. Some children with MIS-C undergo appendectomy before the final diagnosis. There are several hypotheses explaining the pathomechanism of MIS-C, including the central role of the viral antigen persistence in the gut, associated with lymphocyte exhaustion. We aimed to examine appendectomy specimens from MIS-C patients and assess their pathologic features, as well as the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens. Methods: In this cross-sectional study we included 21 children with MIS-C who underwent appendectomy. The control group included 21 sex- and age-matched children with acute appendicitis (AA) unrelated to SARS-CoV-2 infection. Histologic evaluation of appendiceal specimens included hematoxylin and eosin staining and immunohistochemical identification of lymphocyte subpopulations, programmed cell death protein-1 (PD-1) and SARS-CoV-2 nucleocapsid antigen. Results: Appendices of MIS-C patients lacked neutrophilic infiltrate of muscularis propria typical for AA (14% vs. 95%, P < 0.001). The proportion of CD20⁺ to CD5⁺ cells was higher in patients with MIS-C (P = 0.04), as was the proportion of CD4⁺ to CD8⁺ (P < 0.001). We found no proof of SARS-CoV-2 antigen presence, nor lymphocyte exhaustion, in the appendices of MIS-C patients. Conclusions: The appendiceal muscularis of patients with MIS-C lack edema and neutrophilic infiltration typical for AA. SARS-CoV-2 antigens and PD-1 are absent in the appendices of children with MIS-C. These findings argue against the central role of SARS-CoV-2 persistence in the gut and lymphocyte exhaustion as the major triggers of MIS-C.

The COVID-19 pandemic has been met with an unprecedented response from the scientific community, leading to the development, investigation, and authorization of vaccines and antivirals, ultimately reducing the impact of SARS-CoV-2 on global public health. However, SARS-CoV-2 is far from being eradicated, continues to evolve, and causes substantial health and economic burdens. In this narrative review, we posit essential points on SARS-CoV-2 and its responsible management during the transition from the acute phase of the COVID-19 pandemic. As discussed, despite Omicron (sub)variant(s) causing clinically milder infections, SARS-CoV-2 is far from being a negligible pathogen. It requires continued genomic surveillance, particularly if one considers that its future (sub)lineages do not necessarily have to be milder. Antivirals and vaccines remain the essential elements in COVID-19 management. However, the former could benefit from further development and improvements in dosing, while the seasonal administration of the latter requires simplification to increase interest and tackle vaccine hesitancy. It is also essential to ensure the accessibility of COVID-19 pharmaceuticals and vaccines in low-income countries and improve the understanding of their use in the context of the long-term goals of SARS-CoV-2 management. Regardless of location, the primary role of COVID-19 awareness and education must be played by healthcare workers, who directly communicate with patients and serve as role models for healthy behaviors.

The COVID-19 pandemic has been met with an unprecedented response from the scientific community leading to the development, study, and authorization of vaccines and antivirals, ultimately reducing the impact of SARS-CoV-2 on global public health. However, SARS-CoV-2 is far from being eradicated, continues to evolve, and causes substantial health and economic burdens. In this paper, we posit essential points on SARS-CoV-2 and its management during the transition from the acute phase of the COVID-19 pandemic. As discussed, despite Omicron (sub)variant(s) causing clinically milder infections, SARS-CoV-2 is far from being a negligible pathogen. It requires continued genomic surveillance, particularly if one considers that its future (sub)lineages do not necessarily have to be milder. Antivirals and vaccines remain the essential elements in COVID-19 management. However, the former could benefit from further development and improvements in dosing, while the seasonal administration of the latter requires simplification to increase interest and tackle vaccine hesitancy. It is also essential to ensure accessibility of COVID-19 pharmaceuticals and vaccines in low-income countries and improve the understanding of their use in the context of long-term goals of SARS-CoV-2 management. Regardless of location, the primary role of COVID-19 awareness and education must be played by healthcare workers who directly communicate with patients and serve as role models for healthy behaviors.

Multisystem inflammatory syndrome in children (MIS-C) is an immune-mediated complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Cardiovascular system is commonly involved. Acute heart failure (AHF) is the most severe complication of MIS-C, leading to cardiogenic shock. The aim of the study was to characterise the course of MIS-C with a focus on cardiovascular involvement, based on echocardiographic (echo) evaluation, in 498 children (median age 8.3 years, 63% boys) hospitalised in 50 cities in Poland. Among them, 456 (91.5%) had cardiovascular system involvement: 190 (48.2%) of patients had (most commonly atrioventricular) valvular insufficiency, 155 (41.0%) had contractility abnormalities and 132 (35.6%) had decreased left ventricular ejection fraction (LVEF < 55%). Most of these abnormalities improved within a few days. Analysis of the results obtained from two echo descriptions (a median of 5 days apart) revealed a >10% increase in LVEF even in children with primarily normal LVEF. Lower levels of lymphocytes, platelets and sodium and higher levels of inflammatory markers on admission were significantly more common among older children with contractility dysfunction, while younger children developed coronary artery abnormality (CAA) more often. The incidence of ventricular dysfunction might be underestimated. The majority of children with AHF improved significantly within a few days. CAAs were relatively rare. Children with impaired contractility as well as other cardiac abnormalities differed significantly from children without such conditions. Due to the exploratory nature of this study, these findings should be confirmed in further studies.

Background: This study aimed to analyze the differences in the epidemiologic and clinical characteristics of coronavirus disease 2019 (COVID-19) in children hospitalized in 2021, when the severe acute respiratory syndrome coronavirus 2 variants B.1.1.7 (alpha) and B.1.617.2 (delta) dominated, compared with 2020. Methods: In this multicenter study based on the pediatric part of the national SARSTer register (SARSTer-PED), we included 2771 children (0–18 years) with COVID-19 diagnosed between March 1, 2020, and December 31, 2021, from 14 Polish inpatient centers. An electronic questionnaire, which addressed epidemiologic and clinical data, was used. Results: Children hospitalized in 2021 were younger compared with those reported in 2020 (mean 4.1 vs. 6.8 years, P = 0.01). Underlying comorbidities were reported in 22% of the patients. The clinical course was usually mild (70%). A significant difference in the clinical course assessment between 2020 and 2021 was found, with more asymptomatic patients in 2020 and more severely ill children in 2021. In total, 5% of patients were severely or critically ill, including <3% of the participants in 2020 and 7% in 2021. The calculated mortality rate was 0.1% in general and 0.2% in 2021. Conclusion: Infections with severe acute respiratory syndrome coronavirus 2 variants alpha and delta lead to a more severe course of COVID-19 with more pronounced clinical presentation and higher fatality rates than infection with an original strain. Most of the children requiring hospitalization due to COVID-19 do not have underlying comorbidities.

This study aimed to analyze the differences in severity and clinical characteristics of COVID-19 in infants hospitalized in Poland in 2021, when the dominance of variants of concern (VOCs) alpha and delta was reported, compared to 2020, when original (wild) SARS-CoV-2 was dominant (III–IV vs. I–II waves of the pandemic, respectively). In addition, the influence of the presence of comorbidities on the clinical course of COVID-19 in infants was studied. This multicenter study, based on the pediatric part of the national SARSTer database (SARSTer-PED), included 940 infants with COVID-19 diagnosed between March 1, 2020, and December 31, 2021, from 13 Polish inpatient centers. An electronic questionnaire, which addressed epidemiological and clinical data, was used. The number of hospitalized infants was significantly higher in 2021 than in 2020 (651 vs. 289, respectively). The analysis showed similar lengths of infant hospitalization in 2020 and 2021, but significantly more children were hospitalized for more than 7 days in 2020 (p < 0.009). In both analyzed periods, the most common route of infection for infants was household contact. There was an increase in the percentage of comorbidities, especially prematurity, in children hospitalized in 2021 compared to 2020. Among the clinical manifestations, fever was predominant among children hospitalized in 2021 and 2020. Cough, runny nose, and loss of appetite were significantly more frequently observed in 2021 (p < 0.0001). Severe and critical conditions were significantly more common among children with comorbidities. More infants were hospitalized during the period of VOCs dominance, especially the delta variant, compared to the period of wild strain dominance, even though indications for hospitalization did not include asymptomatic patients during that period. The course of COVID-19 was mostly mild, characterized mainly by fever and respiratory symptoms. Comorbidities, particularly from the cardiovascular system and prematurity, were associated with a more severe course of the disease in infants.