Isolated eosinophilic coronary arteritis

Dying "from" or "with" COVID-19 during the Pandemic: Medico-Legal Issues According to a Population Perspective

There is still a lack of knowledge concerning the pathophysiology of death among COVID-19-deceased patients, and the question of whether a patient has died with or due to COVID-19 is still very much debated. In Italy, all deaths of patients who tested positive for SARS-CoV-2 are defined as COVID-19-related, without considering pre-existing diseases that may either contribute to or even cause death. Our study included nine subjects from two different nursing homes (Cases 1–4, Group A; Cases 5–9, Group B). The latter included patients who presumably died from CO poisoning due to a heating system malfunction. All subjects tested positive for COVID-19 both ante- and post-mortem and were examined using post-mortem computed tomography prior to autopsy. COVID-19 was determined to be a contributing cause in the deaths of four out of nine subjects (death due to COVID-19; i.e., pneumonia and sudden cardiac death). In the other five cases, for which CO poisoning was identified as the cause of death, the infection presumably had no role in exitus (death with COVID-19). In our attempt to classify our patients as dying with or due to COVID-19, we found the use of complete assessments (both histological analyses and computed tomography examination) fundamental.

Localized Forms of Vasculitis

Purpose of Review

To provide an updated review on epidemiology, clinical manifestations, diagnostic assessment, treatment, and prognosis of localized vasculitis, following the 2012 Revised International Chapel Hill Consensus Conference Nomenclature on single-organ vasculitis.

Recent Findings

Localized, single-organ vasculitides encompass a group of rare conditions in which there is no evidence of concomitant systemic vasculitis. Most data on this topic derives from case reports and small case series. Although some aspects of these diseases, such as clinical manifestations and histologic findings, have already been extensively investigated, there is still a lack of robust data concerning the pathogenesis, epidemiology, and treatment.

Summary

Localized vasculitides may have a wide range of clinical features depending on the organ affected. The inflammatory process may have a multifocal/diffuse or unifocal distribution. Diagnosis is usually based on histopathology findings and exclusion of systemic vasculitis, which may frequently pose a challenge. Further research on treatment is warranted.

"Idiopathic Eosinophilic Vasculitis": Another Side of Hypereosinophilic Syndrome? A Comprehensive Analysis of 117 Cases in Asthma-Free Patients

BACKGROUND

The absence of asthma may rule out a diagnosis of eosinophilic granulomatosis with polyangiitis in patients with hypereosinophilic syndrome (HES) and features of vasculitis.

OBJECTIVE

To describe eosinophilic vasculitis (EoV) as a possible manifestation of HES in asthma-free patients.

METHODS

We screened our hospital database and the literature for patients with HES who met the following 4 criteria: (1) histopathological or clinical features of EoV (biopsy-proven vasculitis with predominant eosinophilic infiltration of the vessel wall and/or features of vasculitis with tissue and/or blood hypereosinophilia [absolute eosinophil count >1.5 G/L]); (2) no other obvious causes of reactive eosinophilia, organ damage, and vasculitis; (3) the absence of antineutrophil cytoplasmic antibodies; and (4) the absence of current asthma.

RESULTS

Ten of our 83 (12%) asthma-free patients with HES and 107 additional cases in the literature met the criteria for EoV. After a critical analysis of the patients' clinical and laboratory characteristics and outcomes, we identified 41 cases of single-organ EoV (coronary arteritis, n = 29; temporal arteritis, n = 8; cerebral vasculitis, n = 4). Of the remaining 76 patients with EoV, the most frequent manifestations (>10%) were cutaneous vasculitis (56%), peripheral neuropathy (24%), thromboangiitis obliterans-like disease (16%), fever (13%), central nervous system involvement (13%), deep venous thrombosis (12%), and nonasthma lung manifestations (12%). Blood hypereosinophilia more than 1.5 G/L was observed in 79% of patients, and necrotizing vasculitis was observed in 44%.

CONCLUSIONS

Our results suggest that idiopathic EoV (HES-associated vasculitis) can be classified as an eosinophilic-rich, necrotizing, systemic form of vasculitis that affects vessels of various sizes in asthma-free patients.

An autopsy case of sudden unexpected death with loxoprofen sodium-induced allergic eosinophilic coronary periarteritis

Although the cause of eosinophilic coronary periarteritis (ECPA) remains unclear, an allergic background is present in fewer patients than expected. A 50-year-old man with no history of allergy or symptoms suggestive of cardiac or respiratory disorders suddenly died shortly after oral administration of loxoprofen sodium. Autopsy showed eosinophilic coronary periarteritis in three main branches of the coronary arteries, characterized by eosinophil-predominant inflammation without fibrinoid necrosis or granulomatous change in the adventitia and its surroundings of the three main branches of the coronary arteries, in addition to the localized sign of bronchial asthma in the lung. Immunohistochemical examination showed that many mast cells positive for human mast cell tryptase were evident in the perivascular tissue containing peripheral nerve trunks. Whereas the blood concentration of loxoprofen sodium was within the therapeutic range, significant elevation of the serum histamine and tryptase levels was found. The present case suggests that eosinophilic coronary periarteritis may be caused by a type I allergic reaction in some patients and that loxoprofen sodium can trigger a life-threatening type I allergic reaction, including eosinophilic coronary periarteritis, leading to sudden unexpected death.

Eosinophilic Coronary Periarteritis with Arterial Dissection: The Mast Cell Hypothesis

A subset of coronary arterial dissections is associated with eosinophilic coronary periarteritis (ECPA); however, the pathogenesis of the process remains unclear. Mast cells normally reside in coronary arterial adventitia and are known mediators of eosinophilic inflammatory conditions such as type I hypersensitivity reactions. We report two cases in which coronary arterial dissection with ECPA was detected at autopsy. Tryptase, CD68, CD4, CD8, and CD1a immunohistochemical staining was performed to better characterize inflammation. While eosinophils represented a prominent periadventitial inflammatory cell, there were slightly more lymphocytes: CD4/CD8 ratios were within expected reference ranges. There were moderate numbers of macrophages, and few neutrophils or dendritic cells. Numbers of mast cells in dissected versus nondissected sections were compared: adventitial mast cell densities were threefold higher in dissected portions and showed a trend toward increased degranulation. These findings suggest that mast cells may play a role in orchestrating inflammation in cases of ECPA.

Eosinophilic coronary monoarteritis

Eosinophilic coronary monoarteritis is an unfamiliar cause of acute myocardial ischemia. Most commonly, it presents as a left-sided chest pain or sudden death in middle-aged women with no traditional risk factors for coronary artery disease. Because the abrupt onset leaves almost no time for intervention, the symptoms readily lead to death, and most cases are diagnosed at necropsy. Dissection of the coronary artery wall with resultant occlusion of the lumen, which commonly affects the left anterior descending artery, is a consistent gross finding. An inflammatory infiltrate, which is predominantly composed of eosinophils in the tunica adventitia and tunica media and is often accompanied by a hematoma in between these 2 layers, is observed histologically. The etiology remains unclear, but an increase in the activity of eosinophils because of hormonal interactions during pregnancy has been suggested. Interplay of hormones is thought to culminate in the release of histolytic agents by the eosinophils, which initiate the dissection process. Currently, there is no specific treatment for eosinophilic coronary monoarteritis, but cyclophosphamide and prednisone have shown positive results in the treatment of spontaneous coronary artery dissection with unspecified periadventitial inflammation. Percutaneous coronary procedures have also resulted in favorable outcomes in a subset of patients. Because of the high, sudden death rate in eosinophilic coronary monoarteritis, deciphering the underlying pathophysiology of this almost invariably fatal disease remains both a challenge and a key to developing screening methods that will allow timely detection and thus treatment.

Kounis syndrome: a new twist on an old disease

Kounis syndrome is the concurrence of acute coronary syndromes with conditions associated with mast cell activation, such as allergies or hypersensitivity and anaphylactic or anaphylactoid insults that can involve other interrelated and interacting inflammatory cells behaving as a 'ball of thread'. It is caused by inflammatory mediators such as neutral proteases including tryptase and chymase, arachidonic acid products, histamine, platelet activating factor and a variety of cytokines and chemokines released during the activation process. Platelets with FCεRI and FCεRII receptors also participate in the above cascade. Vasospastic allergic angina, allergic myocardial infarction and stent thrombosis with occluding thrombus infiltrated by eosinophils and/or mast cells constitute the three reported variants of this syndrome. Kounis syndrome is a ubiquitus disease that represents a magnificent natural paradigm and nature's own experiment, in a final trigger pathway implicated in cases of coronary artery spasm and plaque rupture. Kounis syndrome can complicate anesthesia, vaccination, medical therapy and stent implantation and it seems to be associated with coronary allograft vasculopathy and takotsubo syndrome, it can often be confused with hypersensitivity myocarditis and can be the cause of unexplained sudden death. Kounis syndrome has revealed that the same mediators released from the same inflammatory cells are present in acute coronary events of nonallergic etiology. These cells are not only present in the culprit region before plaque erosion or rupture but they release their contents just before an actual coronary event. Therefore, does Kounis syndrome represent a magnificent natural paradigm and nature's own experiment in a final trigger pathway implicated in cases of coronary artery spasm and plaque rupture showing a novel way towards our effort to prevent acute coronary syndromes? Drugs, substances targeting the stem cell factor that is essential for mast cell development, proliferation, survival, adhesion and homing as well as monoclonal antibodies and natural molecules that protect mast cell surface and stabilize mast cell membrane could emerge as novel therapeutic ways capable to prevent acute coronary and acute cerebrovascular events.