Vascular Manifestations Research Articles

Association between interferon-I producing plasmacytoid dendritic cells and thrombotic antiphospholipid syndrome.

Background: Thrombotic risk in antiphospholipid syndrome (APS) is conferred by the association of antiphospholipid (aPL) antibodies (first hit) with additional pro-coagulant stimulus (second hit), such as inflammation. Among inflammatory responses, the production of large amounts of interferon (IFN)-I by plasmacytoid dendritic cells (pDCs) is at the basis of the pathophysiology of systemic autoimmune disorders, which raises the hypothesis that this mechanism could also be associated with vascular manifestations of APS. Purpose: Here, we determined the association of pDCs and IFN-I production with thrombotic APS. Research design: Patients with thrombotic primary (t-PAPS) and secondary APS (t-SAPS), asymptomatic aPL carriers and individuals without thrombosis (controls) were included. Data collection and analysis: Circulating pDCs and IFN-α intracellular expression (in the presence or not of oligodeoxynucleotides (CP) stimulus) were quantified by flow cytometry. The expression of five IFN-I inducing genes: ISG15, OASL, Ly6E, MX1, and OAS1 in mononuclear cells was determined by qPCR. Between-group differences were evaluated using chi-square or Kruskal-Wallis tests. Results: A total of 50 patients with t-PAPS, 50 patients with t-SAPS, 20 aPL carriers, and 50 individuals without thrombosis (controls) were included. Intracellular expression of IFN-α was increased after CPG stimulation in both t-SAPS (1.56%; IQR 1.07-2.02) and t-PAPS (0.96%; IQR 0.55-1.24), when compared to aPL carriers (0.71%; IQR 0.42-0.93) and controls (0.48%; IQR 0.24-0.78; p < .0001). ISG15, OASL, Ly6E, MX1, and OAS1 mRNA expressions were higher in t-SAPS (but not in t-PAPS) than in aPL carriers and controls. The expression of proteins and mRNA related to IFN-I response was similar between the triple aPL-positive profile and other aPL profiles. Conclusion: Our results indicate an association of IFN-I response and t-APS. Since IFN-I expression was not increased in aPL carriers or associated with a higher-risk aPL profile, this mechanism does not appear to be related to the presence of aPL alone. IFN-I response could possibly constitute a complementary mechanism for triggering clinical manifestations in APS.

Application of the ICF and OTPF-4 to Conceptualize the Dual Diagnosis of COVID-19 and Stroke: Implications for Occupational Therapy Practice in Acute and Inpatient Rehabilitation

There is mounting evidence that the vascular manifestations associated with COVID-19 are linked to ischemic strokes. The emergence of patients with both COVID-19 and cerebrovascular accidents (COV-CVA) has created a need to adjust occupational therapy service delivery for inpatients with this dual diagnosis. This clinical perspective paper conceptualizes COV-CVA as a health condition using the International Classification of Functioning, Disability and Health Framework (ICF). The Occupational Therapy Practice Framework-4 was used to guide clinical considerations and recommendations for the evaluation, intervention, and discharge planning of patients with COV-CVA.

Malattia di Behçet: una sfida per il pediatra

Behçet’s disease (BD) is a rare chronic inflammatory condition associated with variable-vessel vasculitis, systemic involvement and relapsing course. It is characterized by a wide clinical heterogeneity, presenting with mucocutaneous, ocular, articular, gastrointestinal, neurological and vascular manifestations in the long term, with a high risk of delay in diagnosis: therefore, its morbidity and mortality are significant. The definition of BD probably encompasses a range of disorders with unclear pathogenesis, overlapping autoinflammatory and autoimmune pathological mechanisms. Diagnosis is clinical and multiple classification criteria have been developed. The progressive knowledge about its molecular basis, especially in the so-called monogenic mimics of BD, resulted in an improvement in the disease therapy, with an optimization of the use of conventional immunosuppressive agents and the introduction of new biologic drugs. BD occurs in childhood in up to 20% of cases: paediatric BD differs from adult BD in frequency and severity of clinical findings, and, above all, for a frequent incomplete clinical picture, making the recognition and management of the disease a challenge. The new paediatric classification criteria are aimed to allow an early diagnosis and a proper therapy.

Expanding ACTA2 genotypes with corresponding phenotypes overlapping with smooth muscle dysfunction syndrome.

Pathogenic variants in ACTA2, encoding smooth muscle α-actin, predispose to thoracic aortic aneurysms and dissections. ACTA2 variants altering arginine 179 predispose to a more severe, multisystemic disease termed smooth muscle dysfunction syndrome (SMDS; OMIM 613834). Vascular complications of SMDS include patent ductus arteriosus (PDA) or aortopulmonary window, early-onset thoracic aortic disease (TAD), moyamoya-like cerebrovascular disease, and primary pulmonary hypertension. Patients also have dysfunction of other smooth muscle-dependent systems, including congenital mydriasis, hypotonic bladder, and gut hypoperistalsis. Here,wedescribe five patients with novel heterozygous ACTA2 missense variants,p.Arg179Gly, p.Met46Arg, p.Thr204Ile, p.Arg39Cys, and p.Ile66Asn, who have clinical complications that align or overlap with SMDS. Patients with the ACTA2 p.Arg179Gly and p.Thr204Ile variants display classic features of SMDS. The patient with the ACTA2 p.Met46Arg variant exhibits exclusively vascular complications of SMDS, including early-onset TAD, PDA, and moyamoya-like cerebrovascular disease. Thepatient with the ACTA2 p.Ile66Asn variant has an unusual vascular complication, alarge fusiform internal carotid artery aneurysm. The patient with the ACTA2 p.Arg39Cys variant has pulmonary, gastrointestinal, and genitourinary complications of SMDSbut no vascular manifestations. Identifying pathogenic ACTA2 variants associated with features of SMDS is critical for aggressive surveillance and management of vascular and nonvascular complications and delineating the molecular pathogenesis of SMDS.

Serotonin and systemic sclerosis. An emerging player in pathogenesis.

Systemic sclerosis (SSc) is a complex, autoimmune disease characterized by multiple organ fibrosis and vasculopathy. Experimental and clinical evidence indicates that serotonin is crucially involved in the fibrotic process and mediates vascular manifestations such as Raynaud's phenomenon (RP) or pulmonary arterial hypertension (PAH), all key features of SSc. In this review, we summarize the current knowledge on the potential contribution of serotonin in SSc pathogenesis and provide a rationale for further investigation of this molecule as a therapeutic target. Medline and Cochrane databases were searched from inception to April 2021 using the search terms (systemic sclerosis OR scleroderma OR Raynaud OR Pulmonary arterial hypertension) AND serotonin. Serotonin, a key molecule in an array of central and peripheral functions, has a multifaceted role in regulating fibrosis and vasculopathy. Experimental data suggest that serotonin drives fibrosis in the skin and visceral organs, promotes platelet aggregation, induces vasoconstriction and increases pulmonary vascular resistance. Earlier human trials regarding drugs that inhibit serotonin signaling produced mixed results. However, recent advances in the understanding of the underlying molecular mechanisms could help identify novel therapeutics targeting the serotonin pathway and inform future clinical trials. Serotonin may be a mediator in both fibrosis and vasculopathy. Further exploration of the potential role of serotonin in SSc is justified.

Kazabach–Merritt syndrome without skin manifestations in an infant

The authors observed Kazabach–Merritt syndrome in an infant with an intrathoracic localization of the tumor without vascular manifestations on the skin. The disease was detected by signs of hemopericardium during screening echocardiography in combination with thrombocytopenia and relapses of intrathoracic bleeding. The diagnosis was confirmed by MSCT and biopsy data. Treatment with beta-blockers and chemotherapy resulted in tumor reduction and the disappearance of clinical symptoms.

The Klippel-Trénaunay Syndrome in 2022: Unravelling Its Genetic and Molecular Profile and Its Link to the Limb Overgrowth Syndromes.

The Klippel-Trénaunay syndrome is an unusual syndrome of vascular and dermatologic manifestation in which patients demonstrate hemihypertrophy of the soft tissue and bones of one limb, cutaneous haemangiomas and varicosities in anatomically abnormal positions. Described in 1900 by two French physicians, the etiology remained unclear until recently, when evidence emerged that there was a genetic basis for this sporadic disorder. Genes that encoded pathological angiogenic factors and caused vascular dysmorphogenesis, explaining the molecular bases of this syndrome, were identified. Several angiogenic genes were identified but one gene, the AGGF1 (formerly VG5Q) gene, was seen in mutations involving patients diagnosed with Klippel-Trénaunay syndrome. Furthermore, this syndrome was also noted to have overlapping clinical features linked with the “overgrowth syndromes,” in which genetic mutations along somatic lines were identified. These involved The PI3K enzyme which forms part of the phosphoinositide 3–kinase pathway which is encoded by the PIK3CA-gene. This enzyme mediates embryonic cellular growth in-utero and diseases involved in this pathway are classified as members of the PIK3CA-related overgrowth syndrome. This paper reviews the status of what is now known about the molecular genetics of this unusual, but clinically challenging disorder and its differentiation from similar diseases, linked with the PIK3CA-gene and the related overgrowth syndromes.

Statin-associated immune-mediated necrotizing myositis in Native Americans.

Statin-associated immune-mediated necrotizing myopathy (IMNM) and idiopathic inflammatory myositis (IIM) are myopathies with overlapping features. This study compared the manifestations of IMNM to IIM in Native Americans. Twenty-one Native American patients with inflammatory myopathy (IM) were characterized as to diabetes mellitus, hyperlipidaemia, statin exposure, myopathy diagnosis, muscle histology, autoimmune and myositis-specific autoantibodies, therapy and outcome. IM consisted of 52.4% IMNM, 42.9% IIM and 4.8% metabolic myopathy. IMNM vs IIM patients were older [61.6 years (s.d. 9.8) vs 39.8 (14.3)], diabetes mellitus (100% vs 55.6%), hyperlipidaemia (100% vs 33.3%), statin-exposure (100% vs 22.2%), creatine kinase [CK; 11 780 IU (s.d. 7064) vs 1707 (1658)], anti-3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) antibodies (85.7% vs 11.1%) and necrotizing IM (81.8% vs 11.1%), but shorter disease duration [26.2 months (s.d. 395) vs 78.4 (47.9)], RP (9.1% vs 55.6%), cutaneous manifestations (0% vs 55.6%), ANA (18.2% vs 66.7%) or any autoantibody (18.2% vs 88.9%) (all P < 0.05). MRI abnormalities, histologic IM, myositis-specific autoantibodies, pulmonary hypertension, oesophageal dysfunction, interstitial lung disease, disability and persistently elevated CK were similar. IMNM vs IIM was treated more with IVIG (72.7% vs 11.1%; P = 0.009) and less with antimetabolites (45.5% vs 88.9%; P = 0.05) and rituximab (18.2% vs 55.6%; P = 0.09). IMNM may occur in Native Americans and is associated with diabetes mellitus, hyperlipidaemia, statin use and older age and is characterized by marked CK elevation, necrotizing myopathy and anti-HMGCR antibodies with few cutaneous or vascular manifestations.

Epidemiology and clinical domains of Behçet's disease in the Cantabria region, Northern Spain.

The prevalence of Behçet's disease (BD) has a considerable geographical and temporal variability. Data regarding epidemiology in Spain are limited. Our study aimed to assess the epidemiology and clinical domains of BD in a population-based cohort from Northern Spain and to compare the results with other geographical areas of other countries. We conducted a cross-sectional study of a well-defined population in Northern Spain. Cases of suspected BD between January 1980 and December 2018 were identified. The diagnosis of BD was established according to the International Study Group (ISG) for Behçet's Disease. The incidence of BD between 1999 and 2018 was estimated by sex, age, and year of diagnosis. Of 120 patients with probable BD, 59 patients met ISG criteria and were finally included in the study, with a male/female ratio of 0.97; mean age 49.7±14.7 years. Incidence during the period of study was 0.492 per 100,000 people, observing an increase from January 1999 to December 2018. Prevalence was 10.14 per 100,000 inhabitants in 2018. Clinical manifestations were relapsing aphthous stomatitis (100%), genital ulcers (78%), skin involvement (84.7%), joint involvement (64.4%), uveitis (55.9%), central nervous system (16.9%), vascular (10.2%), and gastrointestinal manifestations (6.8%). The prevalence of BD in Cantabria is higher than in other Southern European countries. This difference may reflect a combination of geographic, genetic, or methodological variations, as well as the free accessibility to the Spanish Public Health System for the entire population. Clinical phenotypes observed are similar to those described in other world regions.

Grape Pomace Extract Attenuates Inflammatory Response in Intestinal Epithelial and Endothelial Cells: Potential Health-Promoting Properties in Bowel Inflammation.

Inflammatory bowel disease (IBD) implies the chronic inflammation of the gastrointestinal tract, combined with systemic vascular manifestations. In IBD, the incidence of cardiovascular disease appears to be related to an increase of oxidative stress and endothelial dysfunction. Grape pomace contains high levels of anti-oxidant polyphenols that are able to counteract chronic inflammatory symptoms. The aim of this study was to determine whether grape pomace polyphenolic extract (GPE) was able to mitigate the overwhelming inflammatory response in enterocyte-like cells and to improve vascular function. Intestinal epithelial Caco-2 cells, grown in monolayers or in co-culture with endothelial cells (Caco-2/HMEC-1), were treated with different concentrations of GPE (1, 5, 10 µg/mL gallic acid equivalents) for 2 h and then stimulated with lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-α for 16 h. Through multiple assays, the expression of intestinal and endothelial inflammatory mediators, intracellular reactive oxygen species (ROS) levels and NF-κB activation, as well as endothelial-leukocyte adhesion, were evaluated. The results showed that GPE supplementation prevented, in a concentration-dependent manner, the intestinal expression and release of interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1, and matrix metalloproteinases (MMP)-9 and MMP-2. In Caco-2 cells, GPE also suppressed the gene expression of several pro-inflammatory markers, such as IL-1β, TNF-α, macrophage colony-stimulating factor (M-CSF), C-X-C motif ligand (CXCL)-10, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and cyclooxygenase (COX)-2. The GPE anti-inflammatory effect was mediated by the inhibition of NF-κB activity and reduced intracellular ROS levels. Furthermore, transepithelial GPE suppressed the endothelial expression of IL-6, MCP-1, VCAM-1, and ICAM-1 and the subsequent adhesion of leukocytes to the endothelial cells under pro-inflammatory conditions. In conclusion, our findings suggest grape pomace as a natural source of polyphenols with multiple health-promoting properties that could contribute to the mitigation of gut chronic inflammatory diseases and improve vascular endothelial function.

Improving U-Net architecture and graph cuts optimization to classify arterioles and venules in retina fundus images

The central retinal artery and its branches supply blood to the inner retina. Vascular manifestations in the retina indirectly reflect the vascular changes and damage in organs such as the heart, kidneys, and brain because of the similar vascular structure of these organs. The diabetic retinopathy and risk of stroke are caused by increased venular caliber. The degrees of these diseases depend on the changes of arterioles and venules. The ratio between the calibers of arterioles and venules (AVR) is various. AVR is considered as the useful diagnostic indicator of different associated health problems. However, the task is not easy because of the lack of information of the features being used to classify the retinal vessels as arterioles and venules. This paper proposed a method to classify the retinal vessels into the arterioles and venules based on improving U-Net architecture and graph cuts. The accuracy of the proposed method is about 97.6%. The results of the proposed method are better than the other methods in RITE dataset and AVRDB dataset.

Q Fever Masquerading as Legionnaires Disease in an Endovascular Stent Infection

Abstract Background Legionellosis in the setting of preexisting endovascular prosthetic graft may represent a Coxiella burnetii infection as antibody cross-reactivity exists. Methods We present a 63-year-old man status-post endovascular aneurysm repair (EVAR) with a history of ankylosing spondylitis, chronic obstructive pulmonary disease asthma, coronary artery disease with myocardial infarction, hypertension, and hyperlipidemia who presented with clinical symptoms of legionellosis. This was confirmed with a positive urine antigen test. Results He completed a 21-day course of azithromycin for Legionella. His leukocytosis and liver function tests normalized, but he had continued lethargy and a persistently elevated erythrocyte sedimentation rate and C-reactive protein. Imaging showed a radiographically infected EVAR graft (placed 10 months prior). The EVAR was explanted and the operating room cultures grew C. burnetii. Prolonged hydroxychloroquine and doxycycline therapy were required for vascular manifestations of Coxiella as azithromycin provides inappropriate coverage. Conclusions Persistent constitutional symptoms in the setting of an EVAR require expanded investigation, especially in the setting of legionellosis.

Predictive value of erythrocyte sedimentation rate and C-reactive protein in Behcet's disease activity and manifestations: a cross-sectional study

BackgroundBehcet’s disease (BD) as a chronic inflammatory condition that affects the eyes, skin, central nervous system, gastrointestinal tract and vessels. According to the literature, the exact value of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in predicting active manifestations of BD remains controversial. In this study, we aim to assess and compare values of ESR and CRP between BD patients with active/inactive BD and active/inactive manifestations of the disease. Moreover, we try to determine the predictive value of ESR and CRP for disease activity.MethodsParticipants (n = 514) were drug-naïve BD patients; Based on last two visits, ESR and CRP values, disease activity, and active manifestations were recorded. The Man-Whitney U test measured the associations, and the binomial logistic regression evaluated the predictive value of ESR and CRP for active disease and each active manifestation. The sensitivity and specificity and the area under the curve (AUC) for each model were determined using receiver operating characteristic curves (ROC). Multiple regressions were run to predict BD activity score from ESR and CRP.ResultPatients with active oral, genital, joint and dermal manifestations had higher ESR and CRP values (Mann–Whitney U test, p < 0.05 for all). Binomial logistic regressions showed that ESR had valuable predictive value for active BD (OR = 1.09 [1.04–1.13], AUC = 0.79 [0.74–0.83], p < 0.001) and active vascular manifestations (1.03 [1.01–1.05], AUC = 0.85 [0.79–0.92], p < 0.001). CRP had good predictive value for active vascular manifestations (OR 1.98 [1.45–2.72], AUC = 0.86 [0.8–0.91], p < 0.001). The optimal value of ESR ≥ 10.5 and ESR ≥ 42.5 could predict active BD and active vascular manifestations with sensitivity, specificity = 71%, 75% and = 81%, 83% respectively.ConclusionsESR and CRP are both associated with active BD and most manifestations of the diseases. They can be used for the prediction of active BD and active vascular manifestations in BD patients. Further studies can help to confirm the findings of the current research.

Vascular complications of Behçet disease.

Behçet disease is a multi-systemic complex vasculitis with unknown etiology characterized by different clinical involvements, including mucocutaneous, ocular, vascular, articular, neurological, and gastrointestinal manifestations. Growing evidence supports that different phenotypes, characterized by clusters of co-existing involvements, can be distinguished. Namely, the vascular phenotype identifies a specific group of patients who suffer from recurrent inflammatory thrombosis and arterial involvement. Vascular disease develops in up to 40% with a definite male preponderance and is usually an early manifestation. Venous involvement is significantly more common than arterial disease, and lower extremity deep vein thrombosis is its most frequent manifestation. Arterial disease involves mostly pulmonary arteries and aorta and manifests mainly in the form of aneurysms. Glucocorticoids and immunosuppressants are the recommended first-line treatments in vasculo-Behçet. Furthermore, controlled trials are still needed to assess the role of adding anticoagulation to the treatment regimen, with an accent on new oral anticoagulants. Treatment with anti-TNF alpha agents seems promising, but the management strategies are not clear yet.

Nonmalignant Features Associated with Inherited Colorectal Cancer Syndromes-Clues for Diagnosis.

Simple SummaryFamiliarity with nonmalignant features and comorbidities of cancer predisposition syndromes may raise awareness and assist clinicians in the diagnosis and interpretation of molecular test results. Genetic predisposition to colorectal cancer (CRC) should be suspected mainly in young patients, in patients with significant family histories, multiple polyps, mismatch repair-deficient tumors, and in association with malignant or nonmalignant comorbidities. The aim of this review is to describe the main nonmalignant comorbidities associated with selected CRC predisposition syndromes that may serve as valuable diagnostic clues for clinicians and genetic professionals.Genetic diagnosis of affected individuals and predictive testing of their at-risk relatives, combined with intensive cancer surveillance, has an enormous cancer-preventive potential in these families. A lack of awareness may be part of the reason why the underlying germline cause remains unexplained in a large proportion of patients with CRC. Various extracolonic features, mainly dermatologic, ophthalmic, dental, endocrine, vascular, and reproductive manifestations occur in many of the cancer predisposition syndromes associated with CRC and polyposis. Some are mediated via the WNT, TGF-β, or mTOR pathways. However the pathogenesis of most features is still obscure. Here we review the extracolonic features of the main syndromes, the existing information regarding their prevalence, and the pathways involved in their pathogenesis. This knowledge could be useful for care managers from different professional disciplines, and used to raise awareness, enable diagnosis, and assist in the process of genetic testing and interpretation.

Carpal tunnel syndrome and Raynaud's phenomenon: a narrative review.

Raynaud's phenomenon (RP) is a recognized symptom associated with carpal tunnel syndrome (CTS) and is also the vascular manifestation of hand arm vibration syndrome (HAVS). The symptoms of HAVS and CTS are such that there is a significant possibility of misdiagnosis and an incorrect attribution of vascular and sensory symptoms. An understanding of the relationship between RP and CTS is essential when undertaking health surveillance of vibration-exposed workers presenting with combined vascular and sensory symptoms. To clarify the relationship between CTS and Raynaud's phenomenon. A systematic search was undertaken of studies that reviewed links between CTS and Raynaud's phenomenon (RP). A total of 4170 papers were identified, with 21 articles that were then reviewed in full, including 1 meta-analysis of 8 studies. Eighteen papers, not included in the meta-analysis, were found including 3 case control studies, 9 case reports, 2 prospective studies and 4 retrospective reviews. Papers were reviewed on the basis of the diagnostic criteria used for CTS and RP. Our review of the literature confirms a substantial body of evidence of a relationship between RP and CTS. It is recommended that assessment of vibration exposed individuals who report concurrent RP and separate sensory symptoms suggestive of, or compatible with CTS, should formally exclude CTS before attributing symptoms to HAVS.

Expression of lncRNAs NEAT1 and lnc-DC in Serum From Patients With Behçet’s Disease Can Be Used as Predictors of Disease

Background: Behçet’s disease (BD) is a chronic autoimmune disease. The early diagnosis of BD is very important to avoid serious and/or fatal complications such as eye damage, severe neurological involvement, and large vessel occlusion. New, sensitive biomarkers would aid in rapid diagnosis, the monitoring of disease activity, and the response to treatment. Methods: This study’s aim is to identify two immune system-related BD biomarkers. We measured long non-coding RNAs (lncRNAs) NEAT1 (nuclear-enriched abundant transcript 1), and lnc-DC (lncRNA in dendritic cells) in serum by real-time polymerase chain reaction (RT-PCR) in 52 BD patients and 52 controls. We analyzed the association between NEAT1 and lnc-DC and the clinical parameters of BD. Receiver operating characteristic (ROC) curve analysis was performed to explore the diagnostic performance of the studied genes. Results: Compared to controls, the significant upregulation of NEAT1 {median [interquartile range (IQR)] = 1.68 (0.38–7.7), p < 0.0001} and downregulation of lnc-DC [median (IQR) = 0.2 (0.12–1.39), p = 0.03] were detected in the sera collected from BD patients. Higher serum expression levels of NEAT1 and lnc-DC were significantly associated with the following clinical presentations: cutaneous lesions, vascular manifestations, articular manifestations, neurological manifestations, and higher disease activity score. Also, high NEAT1 levels were significantly associated with a negative pathergy test, while higher lnc-DC was significantly associated with a positive family history. ROC curves showed that NEAT1 and lnc-DC levels in serum could be used as predictors of BD with high specificity and fair sensitivity. NEAT1 had an area under the curve (AUC) of 0.692 (95% CI: 0.591–0.794, p = 0.001), and lnc-DC had an AUC of 0.615 (95% CI: 0.508–0.723, p = 0.043). Conclusion: Serum lncRNAs NEAT1 and lnc-DC are biomarkers for BD.

Janus Kinase Signaling Pathway and Its Role in COVID-19 Inflammatory, Vascular, and Thrombotic Manifestations.

Acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection continues to be a worldwide public health crisis. Among the several severe manifestations of this disease, thrombotic processes drive the catastrophic organ failure and mortality in these patients. In addition to a well-established cytokine storm associated with the disease, perturbations in platelets, endothelial cells, and the coagulation system are key in triggering systemic coagulopathy, involving both the macro- and microvasculatures of different organs. Of the several mechanisms that might contribute to dysregulation of these cells following SARS-CoV-2 infection, the current review focuses on the role of activated Janus kinase (JAK) signaling in augmenting thrombotic processes and organ dysfunction. The review concludes with presenting the current understanding and emerging controversies concerning the potential therapeutic applications of JAK inhibitors for ameliorating the inflammation-thrombosis phenotype in COVID-19 patients.

Vascular inflammation in the central nervous system.

Vascular inflammation in the central nervous system.

Buerger's Disease May be a Chronic Rickettsial Infection with Superimposed Thrombosis: Literature Review and Efficacy of Doxycycline in Three Patients.

Buerger’s disease (BD) is a chronic inflammatory vasculitis of unknown etiology. The infectious etiology of BD was proposed by Buerger in 1914. Furthermore, there are scattered reports insisting that BD may be related to rickettsial infection, first asserted by Goodman since 1916, followed by Giroud and other French investigators from the 1940s through the 1960s, Nicolau in the 1960s, Bartolo (1980s), and Fazeli (2010s). However, their causal relationship has hardly been accepted because rickettsial infections are known to be acute febrile, vector-borne illnesses, whereas BD is a chronic afebrile illness. In this article we review the relevant literature on the chronic nature of Rickettsia and Orientia infections and on the rickettsial etiology of BD. Excellent initial responses to doxycycline in three patients with BD are briefly described. Based on these findings, we hypothesize that BD patients acquired a rickettsial infection far before the onset of BD. Over years, the infected area expands to become a segment of the infected vessel. Subsequently, thrombus develops on the luminal surface of the infected endothelial cells, which produces the vascular obstructive manifestations of BD. Collectively, it is postulated that BD is a chronic infection with a member of the family Rickettsiaceae with superimposed thrombosis.