A possible pathogenic correlation between neutrophil elastase (NE) enzyme and inflammation in the pathogenesis of coronavirus disease 2019 (COVID-19)

COVID-19: A case for plasma derived natural anticoagulants?

Convalescent plasma was proposed for passive immunization against COVID-19; but so far there are conflicting results and still open questions. However, besides antibodies, other plasma proteins may be good candidates for further research and application. Thromboinflammation frequently complicates severe COVID-19, and classical anticoagulants like heparins seem to have limited effect. The natural protease inhibitors antithrombin III (ATIII), α1-antitrypsin (α1-AT) and α2-macroglobulin (α2-M), which are found decreased in severe COVD-19, play a crucial role in prothrombotic and inflammatory pathways. While ATIII and α1-AT are licensed as commercially prepared therapeutic concentrates, there is no preparation of α2-M available. The diagnostic, prognostic, and even therapeutic potential of plasma protease inhibitors should be further explored.

Evaluation of Salivary Biomarkers and Spirometry for Diagnosing COPD in Non-Smokers and Smokers of Polish Origin

Chronic obstructive pulmonary disease (COPD) is a prevalent respiratory condition with global implications. Accurate and timely diagnosis is critical; however, traditional diagnostic methods (based on spirometry) show limitations, prompting the search for predictive biomarkers and modern diagnostic techniques. This study explored the validation of COPD-related biomarkers (C-reactive protein, procalcitonin, neutrophil elastase, and alpha-1 antitrypsin) in saliva. A diverse cohort, including healthy non-smokers, healthy smokers, and COPD patients of Polish origin, underwent spirometry and marker analysis. The data correlated with clinical factors, revealing noteworthy relations. Firstly, salivary biomarker levels were compared with serum concentrations, demonstrating notable positive or negative correlations, depending on the factor. Further analysis within healthy individuals revealed associations between biomarker levels, spirometry, and clinical characteristics such as age, sex, and BMI. Next, COPD patients exhibited an enhanced concentration of biomarkers compared to healthy groups. Finally, the study introduced a breathing assessment survey, unveiling significant associations between self-perceived breathing and spirometric and tested parameters. Outcomes emphasized the relevance of subjective experiences in COPD research. In conclusion, this research underscored the potential of salivary biomarkers as diagnostic tools for COPD, offering a non-invasive and accessible alternative to traditional methods. The findings paved the way for improved modern diagnostic approaches.

ELANE rs17223045C/T and rs3761007G/A variants: Protective factors against COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for causing coronavirus disease 2019 (COVID-19). The development and severity of this infectious disease is influenced by a combination of environmental and genetic factors. Angiotensin-converting enzyme 2 (ACE2) facilitates SARS-CoV-2 entry into human cells, with transmembrane serine protease 2 (TMPRSS2) playing a crucial role in S protein priming. Other proteases, such as cathepsin L and elastase, neutrophil-expressed (ELANE), have the capability to prime the S protein and contribute to SARS-CoV-2 infection. ELANE variants have not been previously examined in COVID-19 patients. We aimed to assess the association of single nucleotide variants (SNVs) within ELANE with COVID-19 and biochemical markers. The study included 319 SARS-CoV-2-infected patients and 288 controls. Genotyping of ELANE rs17216663C/T (Pro257Leu), rs17223045C/T (As1n30Asn), and rs3761007G/A was conducted using a 5'-nuclease allelic discrimination assay (TaqMan assay). Our findings indicate that ELANE rs17223045C/T (C vs T: odds ratio [OR] 0.08, P = 0.005, and CC vs CT: OR 0.08, P = 0.005) and rs3761007G/A (G vs A: OR 0.38, P = 0.009, and GG vs GA: OR 0.40, P = 0.008) confer protection against COVID-19. However, these variants were not associated with biochemical markers. In conclusion, our data suggests that ELANE rs17223045C/T and rs3761007G/A SNVs may play a protective role against COVID-19.

Neutrophil Activity and Extracellular Matrix Degradation: Drivers of Lung Tissue Destruction in Fatal COVID-19 Cases and Implications for Long COVID

Pulmonary fibrosis, severe alveolitis, and the inability to restore alveolar epithelial architecture are primary causes of respiratory failure in fatal COVID-19 cases. However, the factors contributing to abnormal fibrosis in critically ill COVID-19 patients remain unclear. This study analyzed the histopathology of lung specimens from eight COVID-19 and six non-COVID-19 postmortems. We assessed the distribution and changes in extracellular matrix (ECM) proteins, including elastin and collagen, in lung alveoli through morphometric analyses. Our findings reveal the significant degradation of elastin fibers along the thin alveolar walls of the lung parenchyma, a process that precedes the onset of interstitial collagen deposition and widespread intra-alveolar fibrosis. Lungs with collapsed alveoli and organized fibrotic regions showed extensive fragmentation of elastin fibers, accompanied by alveolar epithelial cell death. Immunoblotting of lung autopsy tissue extracts confirmed elastin degradation. Importantly, we found that the loss of elastin was strongly correlated with the induction of neutrophil elastase (NE), a potent protease that degrades ECM. This study affirms the critical role of neutrophils and neutrophil enzymes in the pathogenesis of COVID-19. Consistently, we observed increased staining for peptidyl arginine deiminase, a marker for neutrophil extracellular trap release, and myeloperoxidase, an enzyme-generating reactive oxygen radical, indicating active neutrophil involvement in lung pathology. These findings place neutrophils and elastin degradation at the center of impaired alveolar function and argue that elastolysis and alveolitis trigger abnormal ECM repair and fibrosis in fatal COVID-19 cases. Importantly, this study has implications for severe COVID-19 complications, including long COVID and other chronic inflammatory and fibrotic disorders.

Exploring the role of tryptophanyl-tRNA synthetase and associations with inflammatory markers and clinical outcomes in COVID-19 patients: A case-control study

Tryptophanyl-tRNA synthetase (WRS) is a critical enzyme involved in protein synthesis, responsible for charging tRNA with the essential amino acid tryptophan. Recent studies have highlighted its novel role in stimulating innate immunity against bacterial and viral infections. However, the significance of WRS in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains elusive. In this study, we aimed to investigate the complex interplay between WRS, inflammatory markers, Toll-like receptor-4 (TLR-4), and clinical outcomes in coronavirus disease 19 (COVID-19) patients. A case-control investigation comprised 127 COVID-19 patients, carefully classified as severe or moderate upon admission, and 112 healthy individuals as a comparative group. Blood samples were meticulously collected before treatment initiation, and WRS, interleukin-6 (IL-6), and C-reactive protein (CRP) concentrations were quantified using a well-established commercial ELISA kit. Peripheral blood mononuclear cells (PBMCs) were isolated from the blood samples, and RNA was extracted for cDNA synthesis. Semi-quantitative real-time polymerase chain reaction (PCR) was employed to assess the relative expression of TLR-4. COVID-19 patients exhibited elevated levels of WRS, IL-6, CRP, and TLR-4 expression compared to healthy individuals, with the severe group displaying significantly higher levels than the moderate group. Notably, severe patients demonstrated substantial fluctuations in CRP, IL-6, and WRS levels over time, a pattern not observed in their moderate counterparts. Although no significant distinctions were observed in the dynamic alterations of WRS, IL-6, CRP, and TLR-4 expression between deceased and surviving patients, a trend emerged indicating higher IL-6_1 levels in deceased patients and elevated lactate dehydrogenase (LDH) levels in severe patients who succumbed to the disease. This pioneering research highlights the dynamic alterations of WRS in COVID-19 patients, providing valuable insights into the correlation between WRS, inflammatory markers, and disease severity within this population. Understanding the role of WRS in SARS-CoV-2 infection may open new avenues for therapeutic interventions targeting innate immunity to combat COVID-19.

Neutrophil elastase in dexmedetomidine alleviating sepsis-related renal injury in rats

BACKGROUND

This research was to investigate the mechanism of neutrophil elastase (NE) in dexmedetomidine (DEX) alleviates sepsis-related renal injury in rats.

METHODS

Sixty healthy male SD rats aged 6-7 weeks were randomly assigned to the control group (Sham group (S group)), Model group (M group), Model + DEX group (M + DEX group), and Model + DEX + Elaspol group (M + DEX + Elaspol (sivelestat) group), with 15 rats in each group. The renal morphology and pathological changes of different groups of rats after modeling were observed, and renal tubular injury was scored. Serum samples were collected at 6 h, 12 h, and 24 h after modeling, and the rats were sacrificed. Renal function indicators, including neutrophil gelatinase-associated lipoprotein (NGAL), kidney injury molecule-1 (KIM-1), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), NE, serum creatinine (SCr), and blood urea nitrogen (BUN), were analyzed by enzyme-linked immunosorbent assay at different time periods. The level of NF-кB in renal tissue was detected by immunohistochemistry.

RESULTS

It was revealed that the general color of renal tissue in M group was dark red, swollen, and congested, and the renal tubular epithelial cells were significantly enlarged, with obvious vacuolar degeneration and inflammatory cell infiltration. Compared with M group, the color and morphology of renal tissue in M + DEX group and M + DEX + Elaspol group were improved, and the amount of inflammatory cell infiltration was reduced. The renal tubular injury score, SCr level, BUN level, NGAL level, KIM-1 level, TNF-α, IL-6, NE level, and NF-кB level in M group were significant different from S group 12 h after the operation (P < 0.001). The renal tubular injury score, SCr level, BUN level, NGAL level, KIM-1 level, TNF-α, IL-6, NE level, and NF-кB level in M + DEX group were significant different from M group (P < 0.01). The renal tubular injury score, SCr level, BUN level, NGAL level, KIM-1 level, TNF-α, IL-6, NE level, and NF-кB level in M + DEX + Elaspol group were significant different from those in M group at 12 h after the operation (P < 0.001).

CONCLUSION

NE plays an active role in the reduction of sepsis-related renal injury in rats by inhibiting the inflammatory response.

Alpha-2 macroglobulin activity in SARS-CoV-2 induced infection and in the post-COVID-19 period

The universal proteinase inhibitor α2-macroglobulin (α₂-MG) exhibiting antiviral and immunomodulatory activities, is considered as an important participant in the infectious process. The activity of α₂-MG in the new coronavirus infection and post-covid syndrome (long COVID) has not been studied yet. We examined 85 patients diagnosed with community-acquired bilateral polysegmental pneumonia developed under conditions of a new coronavirus infection SARS-CoV-2. For assessment of the post-COVID period, 60 patients were examined 5.0±3.6 months after the coronavirus infection. Among these patients, 40 people had complications, manifested in the form of neurological, cardiological, gastroenterological, dermatological, bronchopulmonary symptoms. The control group included 30 conditionally healthy individuals with a negative PCR result for SARS-CoV-2 RNA and lack of antibodies to the SARS-CoV-2 virus. The α₂-MG activity in serum samples of patients with coronavirus infection dramatically decreased, up to 2.5% of the physiological level. This was accompanied by an increase in the activity of the α₁-proteinase inhibitor, elastase- and trypsin-like proteinases by 2.0-, 4.4- and 2.6-fold respectively as compared with these parameters in conditionally healthy individuals of the control. In the post-COVID period, despite the trend towards normalization of the activity of inhibitors, the activity of elastase-like and especially trypsin-like proteinases in serum remained elevated. In overweight individuals, the increase in the activity of trypsin-like proteinases was most pronounced and correlated with an increase in the antibody titer to the SARS-CoV-2 virus. In the post-COVID period, the α₂-MG activity not only normalized, but also exceeded the control level, especially in patients with dermatological and neurological symptoms. In patients with neurological symptoms or with dermatological symptoms, the α₂-MG activity was 1.3 times and 2.1 times higher than in asymptomatic persons. Low α₂-MG activity in the post-COVID period persisted in overweight individuals. The results obtained can be used to monitor the course of the post-COVID period and identify risk groups for complications.

Recent developments in the immunopathology of COVID-19

There has been an important change in the clinical characteristics and immune profile of Coronavirus disease 2019 (COVID-19) patients during the pandemic thanks to the extensive vaccination programs. Here, we highlight recent studies on COVID-19, from the clinical and immunological characteristics to the protective and risk factors for severity and mortality of COVID-19. The efficacy of the COVID-19 vaccines and potential allergic reactions after administration are also discussed. The occurrence of new variants of concerns such as Omicron BA.2, BA.4, and BA.5 and the global administration of COVID-19 vaccines have changed the clinical scenario of COVID-19. Multisystem inflammatory syndrome in children (MIS-C) may cause severe and heterogeneous disease but with a lower mortality rate. Perturbations in immunity of T cells, B cells, and mast cells, as well as autoantibodies and metabolic reprogramming may contribute to the long-term symptoms of COVID-19. There is conflicting evidence about whether atopic diseases, such as allergic asthma and rhinitis, are associated with a lower susceptibility and better outcomes of COVID-19. At the beginning of pandemic, the European Academy of Allergy and Clinical Immunology (EAACI) developed guidelines that provided timely information for the management of allergic diseases and preventive measures to reduce transmission in the allergic clinics. The global distribution of COVID-19 vaccines and emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with reduced pathogenic potential dramatically decreased the morbidity, severity, and mortality of COVID-19. Nevertheless, breakthrough infection remains a challenge for disease control. Hypersensitivity reactions (HSR) to COVID-19 vaccines are low compared to other vaccines, and these were addressed in EAACI statements that provided indications for the management of allergic reactions, including anaphylaxis to COVID-19 vaccines. We have gained a depth knowledge and experience in the over 2 years since the start of the pandemic, and yet a full eradication of SARS-CoV-2 is not on the horizon. Novel strategies are warranted to prevent severe disease in high-risk groups, the development of MIS-C and long COVID-19.

Sars-Cov2 Induced Biochemical Mechanisms in Liver Damage and Intestinal Lesions

Multiple pathogenic mechanisms are found in SARS-CoV2 systemic inflammation. Oxidative stress, altered proteolysis, hypercoagulation, and metabolic disorders are significant in virus-induced lesions. The study aimed to investigate the biochemical mechanism of virus-induced disorders and determine the biochemical features in SARS-CoV2-associated liver damage and intestine lesions. A retrospective case series of ninety-two patients diagnosed with COVID-19 pnemonia. The ACE, α1-proteinase inhibitor, trypsin-like proteinase, and elastase activity were measured. Nitrites level was detected in reaction with Griess reagent. The ELISA kit measured Troponin, C-peptide, leptin, adiponectin, PAR4, and neuropilin level. It was obtained an increase in ACE activity and nitrites ions content in SARS-CoV2 associated patients. The hyperglycemia and an increase in adipose tissue-derived hormones guided the virus-induced metabolic disorders. Proteolysis activation was revealed in SARS-CoV2 pneumonia patients. The found molecular event was accompanied by hyperglycemia induction. Multiorgan lesions manifest in in cardiac failure, which was detected in patients with ARDS. Moreover, high arterial blood pressure in patients with COVID-19 was associated with the hyperglycemia and increased ACE activity and NO ions level. Liver damage was specific for COVID-19-associated patients with severe ARDS and heart failure. Proteolysis overactivation resulting in vasoactive substances imbalance was detected in patients with the intestinal lesions. The obtained data shows the the neuropilin-dependent axis in damage prevalence in the intestine. Metabolic disorders resulting in the growth of adipose-derived tissue hormones, nitrites, and neuropilin levels was triggered by prolonged inflammation. So, the impaired metabolism and SARS-CoV2 associated hyperglycemia influence on SARS-CoV2 multiple mechanisms. Gastrointestinal manifestations in SARS-CoV2 infection was found to be related to various biochemical and molecular tools. ACE2 receptors axis is prevalent for liver damage, but NRP-1 protein (neuropilin), NO derivatives, and adipose tissue-derived hormones are essential for intestinal lesions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12291-022-01089-x.

The derived neutrophil to lymphocyte ratio can be the predictor of prognosis for COVID-19 Omicron BA.2 infected patients

BACKGROUND

Several systemic inflammatory biomarkers have been associated with poor overall survival (OS) and disease severity in patients with coronavirus disease 2019 (COVID-19). However, it remains unclear which markers are better for predicting prognosis, especially for COVID-19 Omicron BA.2 infected patients. The present study aimed to identify reliable predictors of prognosis of COVID-19 Omicron BA.2 from inflammatory indicators.

METHODS

A cohort of 2645 COVID-19 Omicron BA.2 infected patients were retrospectively analyzed during the Omicron BA.2 surge in Shanghai between April 12, 2022, and June 17, 2022. The patients were admitted to the Shanghai Fourth People's Hospital, School of Medicine, Tongji University. Six systemic inflammatory indicators were included, and their cut-off points were calculated using maximally selected rank statistics. The analysis involved Kaplan-Meier curves, univariate and multivariate Cox proportional hazard models, and time-dependent receiver operating characteristic curves (time-ROC) for OS-associated inflammatory indicators.

RESULTS

A total of 2347 COVID-19 Omicron BA.2 infected patients were included. All selected indicators proved to be independent predictors of OS in the multivariate analysis (all P < 0.01). A high derived neutrophil to lymphocyte ratio (dNLR) was associated with a higher mortality risk of COVID-19 [hazard ratio, 4.272; 95% confidence interval (CI), 2.417-7.552]. The analyses of time-AUC and C-index showed that the dNLR (C-index: 0.844, 0.824, and 0.718 for the 5^th, 10^th, and 15^th day, respectively) had the best predictive power for OS in COVID-19 Omicron BA.2 infected patients. Among different sub-groups, the dNLR was the best predictor for OS regardless of age (0.811 for patients aged ≥70 years), gender (C-index, 0.880 for men and 0.793 for women) and disease severity (C-index, 0.932 for non-severe patients and 0.658 for severe patients). However, the platelet to lymphocyte ratio was superior to the other indicators in patients aged <70 years.

CONCLUSIONS

The prognostic ability of the dNLR was higher than the other evaluated inflammatory indicators for all COVID-19 Omicron BA.2 infected patients.

The deciphering of the immune cells and marker signature in COVID-19 pathogenesis: An update

The precise interaction between the immune system and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical in deciphering the pathogenesis of coronavirus disease 2019 (COVID-19) and is also vital for developing novel therapeutic tools, including monoclonal antibodies, antivirals drugs, and vaccines. Viral infections need innate and adaptive immune reactions since the various immune components, such as neutrophils, macrophages, CD4⁺ T, CD8⁺ T, and B lymphocytes, play different roles in various infections. Consequently, the characterization of innate and adaptive immune reactions toward SARS-CoV-2 is crucial for defining the pathogenicity of COVID-19. In this study, we explain what is currently understood concerning the conventional immune reactions to SARS-CoV-2 infection to shed light on the protective and pathogenic role of immune response in this case. Also, in particular, we investigate the in-depth roles of other immune mediators, including neutrophil elastase, serum amyloid A, and syndecan, in the immunopathogenesis of COVID-19.

The emerging role of microbiota-derived short-chain fatty acids in immunometabolism

The accumulating evidence revealed that microbiota plays a significant function in training, function, and the induction of host immunity. Once this interaction (immune system-microbiota) works correctly, it enables the production of protective responses against pathogens and keeps the regulatory pathways essential for maintaining tolerance to innocent antigens. This concept of immunity and metabolic activity redefines the realm of immunometabolism, paving the way for innovative therapeutic interventions to modulate immune cells through immune metabolic alterations. A body of evidence suggests that microbiota-derived metabolites, including short-chain fatty acids (SCFAs) such as butyrate, acetate, and propionate, play a key role in immune balance. SCFAs act on many cell types to regulate various vital biological processes, including host metabolism, intestinal function, and the immune system. Such SCFAs generated by gut bacteria also impact immunity, cellular function, and immune cell fate. This is a new concept of immune metabolism, and better knowledge about how lifestyle affects intestinal immunometabolism is crucial for preventing and treating disease. In this review article, we explicitly focus on the function of SCFAs in the metabolism of immune cells, especially macrophages, neutrophils, dendritic cells (DCs), B cells, T (Th) helper cells, and cytotoxic T cells (CTLs).

Neutrophil Extracellular Traps, Sepsis and COVID-19 - A Tripod Stand

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19) pandemic. Majority of COVID-19 patients have mild disease but about 20% of COVID-19 patients progress to severe disease. These patients end up in the intensive care unit (ICU) with clinical manifestations of acute respiratory distress syndrome (ARDS) and sepsis. The formation of neutrophil extracellular traps (NETs) has also been associated with severe COVID-19. Understanding of the immunopathology of COVID-19 is critical for the development of effective therapeutics. In this article, we discuss evidence indicating that severe COVID-19 has clinical presentations consistent with the definitions of viral sepsis. We highlight the role of neutrophils and NETs formation in the pathogenesis of severe COVID-19. Finally, we highlight the potential of therapies inhibiting NETs formation for the treatment of COVID-19.

Coronavirus disease 2019 (COVID-19) update: From metabolic reprogramming to immunometabolism

The field of immunometabolism investigates and describes the effects of metabolic rewiring in immune cells throughout activation and the fates of these cells. Recently, it has been appreciated that immunometabolism plays an essential role in the progression of viral infections, cancer, and autoimmune diseases. Regarding COVID‐19, the aberrant immune response underlying the progression of diseases establishes two major respiratory pathologies, including acute respiratory distress syndrome (ARDS) or pneumonia‐induced acute lung injury (ALI). Both innate and adaptive immunity (T cell‐based) were impaired in the course of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. Current findings have deciphered that macrophages (innate immune cells) are involved in the inflammatory response seen in COVID‐19. It has been demonstrated that immune system cells can change metabolic reprogramming in some conditions, including autoimmune diseases, cancer, and infectious disease, including COVID‐19. The growing findings on metabolic reprogramming in COVID‐19 allow an exploration of metabolites with immunomodulatory properties as future therapies to combat this hyperinflammatory response. The elucidation of the exact role and mechanism underlying this metabolic reprograming in immune cells could help apply more precise approaches to initial diagnosis, prognosis, and in‐hospital therapy. This report discusses the latest findings from COVID‐19 on host metabolic reprogramming and immunometabolic responses.

Role of Genetic Variants and Host Polymorphisms on COVID‐19: From Viral Entrance Mechanisms to Immunological Reactions

Coronavirus disease 2019 (COVID‐19), caused by a highly pathogenic emerging virus, is called severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Knowledge regarding the pathogenesis of this virus is in infancy; however, investigation on the pathogenic mechanisms of the SARS‐CoV‐2 is underway. In COVID‐19, one of the most remarkable characteristics is the wide range of disease manifestation and severity seen across individuals of different ethnic backgrounds and geographical locations. To effectively manage COVID‐19 in the populations, beyond SARS‐CoV‐2 detection, serological response assessment, and analytic techniques, it is critical to obtain knowledge about at‐risk individuals and comprehend the identified variations in the disease's severity in general and also in the populations' levels. Several factors can contribute to variation in disease presentation, including population density, gender and age differences, and comorbid circumstances including diabetes mellitus, hypertension, and obesity. Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility. Besides this, COVID‐19 has also been linked with a higher risk of mortality in men and certain ethnic groups, revealing that host genetic characteristics may affect the individual risk of death. Also, genetic variants involved in pathologic processes, including virus entrance into cells, antiviral immunity, and inflammatory response, are not entirely understood. Regarding SARS‐CoV‐2 infection characteristics, the present review suggests that various genetic polymorphisms influence virus pathogenicity and host immunity, which might have significant implications for understanding and interpreting the matter of genetics in SARS‐CoV‐2 pathogenicity and customized integrative medical care based on population investigation.

Genetic factors presumably influence SARS‐CoV‐2 infection susceptibility.

Genetic variants were involved in the pathologic processes of SARS‐CoV‐2 infection.

Various genetic polymorphisms influence virus pathogenicity and host immunity.

Human leukocyte antigens (HLAs) may play a vital role in SARS‐CoV‐2 susceptibility.

Polymorphisms in several genes such as IL‐6, TMPRSS2, IFITM3, CD26, ACE, and DBP were associated with the COVID‐19 severity.

Eosinophilic granulomatosis with polyangiitis after COVID-19: A case report

COVID-19 can damage the endothelial cells of every organ in the body and lead to vasculopathy and vasculitis. It has been shown that various types of vasculitis could be a new manifestation of COVID-19. Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic necrotizing vasculitis that affects small vessels. Here we report our experience with a 42-year-old man with a 3-weeks history of fever of unknown origin after two months from COVID-19 recovery presented with loss of appetite, loss of weight, and paresthesia in his lower extremities. After required evaluations including nerve biopsy, EGPA was diagnosed for him.

Idiopathic thrombocytopenic purpura as a hematologic manifestation of COVID-19 infection: A case report

The hematologic system is one of the vulnerable parts of the human body in coronavirus disease-2019 (COVID-19) infection. Lymphopenia and disseminated intravascular coagulation (DIC) are among the most frequent consequences of COVID-19. Idiopathic thrombocytopenic purpura is one of the common causes of thrombocytopenia in adults. It is defined by thrombocytopenia when platelet counts <105/μl in the absence of anemia and leukopenia. Traditionally, infections, typically viral, have been known as the main culprits of low platelet counts before the involvement of ITP. According to the literature, C virus (HCV), HIV, varicella-zoster virus (VZV), and cytomegalovirus (CMV) are considered secondary causative agents for the development of ITP. In this study, we reported a case that was afflicted with concurrent severe thrombocytopenia diagnosed as ITP and COVID-19 infection.