Adverse Hematological Effects of COVID-19 Vaccination and Pathomechanisms of Low Acquired Immunity in Patients with Hematological Malignancies

Unexpected hypereosinophilia after Sinopharm vaccination: a case report

BACKGROUND

COVID-19 vaccines have been pivotal in the management of the recent pandemic. However, despite their safety and efficacy, apprehension regarding possible adverse effects has always been raised. Most of the vaccine-related side effects are mild. However, serious complications like anaphylaxis and thromboembolic events have also been reported. Various hematological disorders, including hypereosinophilia, have been reported following COVID-19 vaccination, the exact mechanisms of which remain unclear.

CASE PRESENTATION

We report a 66-year-old male who developed hypereosinophilia (absolute eosinophil count: 4063 cells/µL) and lymphadenopathy two months after receiving the third dose of the BBIBP-CorV (Sinopharm) COVID-19 vaccine. Extensive investigations failed to identify an alternative cause for these findings.

CONCLUSIONS

This case report underscores the potential for unexpected hematological adverse events following COVID-19 vaccination, even with inactivated vaccines. While a definitive causal relationship cannot be established, the temporal association between vaccination and symptom onset warrants further investigation. This case emphasizes the importance of continued surveillance for rare adverse events and additional research to elucidate the potential mechanisms underlying vaccine-associated eosinophilia.

Role of Gut Microbiota in Long COVID: Impact on Immune Function and Organ System Health

SARS-CoV-2 infection has led to a range of long-lasting symptoms, collectively referred to as long COVID. Current research highlights the critical role of angiotensin-converting enzyme 2 (ACE2) in regulating gut microbiota diversity, vascular function, and homeostasis within the renin-angiotensin system (RAS). ACE2 is utilized by the SARS-CoV-2 virus to enter host cells, but its downregulation following infection contributes to gut microbiota dysbiosis and RAS disruption. These imbalances have been linked to a range of long COVID symptoms, including joint pain, chest pain, chronic cough, fatigue, brain fog, anxiety, depression, myalgia, peripheral neuropathy, memory difficulties, and impaired attention. This review investigates the dysregulation caused by SARS-CoV-2 infection and the long-term effects it has on various organ systems, including the musculoskeletal, neurological, renal, respiratory, and cardiovascular systems. We explored the bidirectional interactions between the gut microbiota, immune function, and these organ systems, focusing on how microbiota dysregulation contributes to the chronic inflammation and dysfunction observed in long COVID symptoms. Understanding these interactions is key for identifying effective therapeutic strategies and interventional targets aimed at mitigating the impact of long COVID on organ health and improving patient outcomes.

Impact of Immune Abnormalities on COVID-19 Vaccine Effectiveness in Infected Patients

Objective To assess the protective effect of COVID-19 vaccines in patients with varying immune states by analyzing lactate dehydrogenase (LDH), C-reactive protein (CRP), and D-dimer (D-Di) levels in COVID-19-infected individuals under different vaccination scenarios and immune statuses. Methods This is a single-center retrospective study involving 338 SARS-CoV-2-infected patients treated at a tertiary medical center in Foshan, China, between November 2022 and January 2023. The primary outcome was the vaccine's protective effect on LDH, CRP, and D-Di levels. Results Vaccinated patients had shorter hospital stays and less severe lung involvement (P < 0.05), particularly in immunocompromised individuals. In immunocompromised patients, LDH and CRP levels were elevated, but in the vaccine group, fewer patients developed abnormally high CRP, D-Di, and coagulation-related complications. Vaccination reduced LDH and CRP levels in immunocompetent patients and lowered CRP levels regardless of immune status. In addition, people who are both immunocompromised and vaccinated have a higher risk of developing microthrombosis. Conclusions COVID-19 vaccination generally improves LDH, CRP, and D-Di levels, particularly in immunocompromised patients, supporting vaccination efforts. However, a subset of immunocompromised and vaccinated patients exhibited higher D-Di levels upon hospital admission, suggesting a complex interplay between vaccination, immune status, and the risk of microthrombosis. This finding emphasizes the need for further investigation into the role of immune function in disease severity and vaccine response.

Strategies to Minimize Virus Transmission During Anesthesia Procedures in COVID-19 Patients

Anesthesiologists and the critical care team may be at increased risk of contracting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, COVID-19) due to airway manipulations and intubations performed during anesthesia administration and management of patient undergoing surgery. SARS-CoV-2 infections have been reported among healthcare workers. The virus is transmitted by close personal contact and aerosols. During intubation and other procedures involving the airway, the anesthesiologist is especially susceptible to aerosols. We performed a systematic analysis of the published reports on potential effects of COVID-19 during surgery on the anesthesiologist and critical care team. and identified potential immunomodulatory effects of general anesthetics in the presence of COVID-19 infection in patients. The article also provides critical discussion on the current medical management of COVID-19 and highlights the evidence-based key points for a safer practice during anesthesia administration and surgeries both in children and adults, including obstetric procedures and how it could affect pregnant women receiving anesthesia. With regional anesthesia, airway manipulation is not necessary, and healthcare workers and other patients are less likely to contract the same infection.

A Rapid Review of the Effects of the COVID-19 Vaccine Among Individuals Taking Clozapine

BACKGROUND

The COVID-19 pandemic prompted the rapid development of vaccines to combat the virus. Several COVID-19 vaccines have proven effective in preventing infection, hospitalization, and death. Vaccination has been especially recommended for vulnerable populations, such as individuals with psychiatric illnesses who face increased risks due to comorbidities and socioeconomic factors. This rapid review identifies and analyzes the effects of COVID-19 vaccines among individuals taking clozapine.

METHODS

The review included articles from PubMed, OVID, Clinical Key, Web of Science, and Google Scholar, published between September 2020 and December 2023. Inclusion criteria were peer-reviewed journals, English language, patients on clozapine receiving a COVID-19 vaccine, and documented vaccine-related adverse effects.

RESULTS

Twelve articles were included, consisting of 8 case reports, 1 cross-sectional study, and 3 prospective observational studies, involving 298 subjects, with 9 subjects from case reports. After the first vaccine dose, 27 of 248 subjects experienced adverse effects, with 1 case report advising a temporary halt and dose reduction of clozapine. The subject in this case was admitted in a delirious state 4 days after vaccination with repeated falls and urinary incontinence; active infectious and neurologic etiologies were ruled out. Second dose data were available for 261 subjects, with 31 reporting adverse effects. Adverse effects included hematological changes, delirious state, seizures, and fever.

CONCLUSIONS

The review suggests that individuals on clozapine receiving COVID-19 vaccines may experience adverse effects. Clozapine levels and immune system interactions should be monitored in these cases.

Characterization and trajectories of hematological parameters prior to severe COVID-19 based on a large-scale prospective health checkup cohort in western China: a longitudinal study of 13-year follow-up

BACKGROUND

The relaxation of the "zero-COVID" policy on Dec. 7, 2022, in China posed a major public health threat recently. Complete blood count test was discovered to have complicated relationships with COVID-19 after the infection, while very few studies could track long-term monitoring of the health status and identify the characterization of hematological parameters prior to COVID-19.

METHODS

Based on a 13-year longitudinal prospective health checkup cohort of ~ 480,000 participants in West China Hospital, the largest medical center in western China, we documented 998 participants with a laboratory-confirmed diagnosis of COVID-19 during the 1 month after the policy. We performed a time-to-event analysis to explore the associations of severe COVID-19 patients diagnosed, with 34 different hematological parameters at the baseline level prior to COVID-19, including the whole and the subtypes of white and red blood cells.

RESULTS

A total of 998 participants with a positive SARS-CoV-2 test were documented in the cohort, 42 of which were severe cases. For white blood cell-related parameters, a higher level of basophil percentage (HR = 6.164, 95% CI = 2.066-18.393, P = 0.001) and monocyte percentage (HR = 1.283, 95% CI = 1.046-1.573, P = 0.017) were found associated with the severe COVID-19. For lymphocyte-related parameters, a lower level of lymphocyte count (HR = 0.571, 95% CI = 0.341-0.955, P = 0.033), and a higher CD4/CD8 ratio (HR = 2.473, 95% CI = 1.009-6.059, P = 0.048) were found related to the risk of severe COVID-19. We also observed that abnormality of red cell distribution width (RDW), mean corpuscular hemoglobin concentration (MCHC), and hemoglobin might also be involved in the development of severe COVID-19. The different trajectory patterns of RDW-SD and white blood cell count, including lymphocyte and neutrophil, prior to the infection were also discovered to have significant associations with the risk of severe COVID-19 (all P < 0.05).

CONCLUSIONS

Our findings might help decision-makers and clinicians to classify different risk groups of population due to outbreaks including COVID-19. They could not only optimize the allocation of medical resources, but also help them be more proactive instead of reactive to long COVID-19 or even other outbreaks in the future.

Distinguishing Swine Flu (H1N1) from COVID-19: Clinical, Virological, and Immunological Perspectives

This article provides an in-depth examination on the differences between the influenza A strain, H1N1 (also called Swine Flu) and Covid-19 focusing on the immune response and clinical symptoms. Flu symptoms due to influenza A strain, H1N1, were initially discovered in 2009. This variant of influenza A is believed to have emerged through reassortment, a process where the resulting virus inherits gene segments from each of its parental viruses. This reassortment event has resulted in a variant with altered characteristics, potentially affecting the level of immunity in humans. The symptoms of this strain typically manifest 1-4 days after exposure and include fever, cough, sore throat, runny/stuffy nose, body aches, fatigue, and gastrointestinal symptoms such as diarrhea. The transmission dynamics of this new variant, including human-to-human transmission, are still under investigation by health authorities. Individuals with weakened immune systems are generally more susceptible to severe illness. Risk factors associated with swine flu can include older adults, young children, pregnant women, and individuals with obesity. Historical variants of swine flu, such as the 2015 variant in India, have been associated with significant case numbers and deaths, often due to respiratory failure. Since the epidemic of Covid-19 due to SARS-CoV2 in early 2020, several symptoms of COVID-19 and swine flu overlap. In this article, we critically reviewed the differences and similarities in the immune response and clinical symptoms due to H1N1 virus and SARS-CoV2 in human.

COVID-19 and Kidney: The Importance of Follow-Up and Long-Term Screening

Renal involvement and kidney injury are common in COVID-19 patients, and the symptoms are more severe if the patient already has renal impairment. Renal involvement in COVID-19 is multifactorial, and the renal tubule is mainly affected, along with podocyte injury during SARS-CoV-2 infection. Inflammation, complement activation, hypercoagulation, and crosstalk between the kidney and lungs, brain, and heart are contributory factors. Kidney injury during the acute phase, termed acute kidney injury (AKI), may proceed to chronic kidney disease if the patient is discharged with renal impairment. Both AKI and chronic kidney disease (CKD) increase mortality in COVID-19 patients. Further, COVID-19 infection in patients suffering from CKD is more severe and increases the mortality rate. Thus, it is important to address both categories of patients, either developing AKI or CKD after COVID-19 or previously having CKD, with proper management and treatment. This review discusses the pathophysiology involved in AKI and CKD in COVID-19 infection, followed by management and treatment of AKI and CKD. This is followed by a discussion of the importance of screening and treatment of CKD patients infected with COVID-19 and future perspectives to improve treatment in such patients.