Cardiogenic Shock due to Kounis Syndrome following Cobra Bite

Cellular and Molecular Mechanisms of Mast Cells in Atherosclerotic Plaque Progression and Destabilization

Mast cells (MCs) are commonly recognized for their crucial involvement in the pathogenesis of allergic diseases, but over time, it has come to light that they also play a role in the pathophysiology of non-allergic disorders including atherosclerosis. The involvement of MCs in the pathology of atherosclerosis is supported by their accumulation in atherosclerotic plaques upon their progression and the association of intraplaque MC numbers with acute cardiovascular events. MCs that accumulate within the atherosclerotic plaque release a cocktail of mediators through which they contribute to neovascularization, plaque progression, instability, erosion, rupture, and thrombosis. At a molecular level, MC-released proteases, especially cathepsin G, degrade low-density lipoproteins (LDL) and mediate LDL fusion and binding of LDL to proteoglycans (PGs). Through a complicated network of chemokines including CXCL1, MCs promote the recruitment of among others CXCR2+ neutrophils, therefore, aggravating the inflammation of the plaque environment. Additionally, MCs produce extracellular traps which worsen inflammation and contribute to atherothrombosis. Altogether, evidence suggests that MCs actively, via several underlying mechanisms, contribute to atherosclerotic plaque destabilization and acute cardiovascular syndromes, thus, making the study of interventions to modulate MC activation an interesting target for cardiovascular medicine.

Kounis syndrome after anti-snake venom intradermal skin test: A case report

Snake bites are a concerning health problem in Egypt and other tropical countries that are effectively managed with anti-snake venom (ASV). ASV has common reactive complications that are usually mild. Rarely, anaphylaxis and severe systemic reactions may occur following ASV. In this case report, we present a rare condition of Kounis syndrome, acute allergic myocardial infarction, in a young man during anaphylaxis following an allergic intradermal test of VACSERA snake antivenom.

Kounis Syndrome: Bee Sting-Induced Acute Myocardial Infarction

Acute coronary syndrome or ST-elevation myocardial infarction that develops as a hypersensitive reaction following exposure to an allergen, such as chemicals or bee or wasp stings, is known as Kounis syndrome (KS). Based on angiographic characteristics, three kinds of KS have been identified. Multiple bee stings typically result in localized allergic reactions and anaphylaxis, but they can also occasionally induce severe systemic toxic reactions. Here, a case of KS in a 50-year-old male presented with swelling on the face and upper limbs and breathing difficulties resulting from bee stings which led to myocardial infarction. The risk of KS should be considered by the physician at the primary level in all situations involving multiple bee bites.

Kounis Syndrome Secondary to Medicine-Induced Hypersensitivity

Introduction

Kounis syndrome is the concurrence of an acute coronary syndrome (ACS) caused by coronary vasospasms, acute myocardial infarctions, or stent thromboses in case of allergic or hypersensitivity reactions. Kounis syndrome is mediated by mast cells that interact with macrophages and T-lymphocytes, causing degranulation and inflammation with cytokine release. It is a life-threatening condition that has many trigger factors and is most commonly caused by medicines. Case Presentation. A 71-year-old male was admitted with a fever of five days' duration associated with cellulitis, for which he had been treated with clindamycin and flucloxacillin before admission. He was a diagnosed patient with hypertension and dyslipidemia five years ago. After taking the antibiotics, he had developed generalized itching followed by urticaria suggesting an allergic reaction. Therefore, he was admitted to the hospital. After admission, he developed an ischaemic-type chest pain associated with autonomic symptoms and shortness of breath. An immediate ECG was taken that showed ST-segment depressions in the chest leads V4–V6, confirmed by a repeat ECG. Troponin I was 8 ng/mL. Acute management of ACS was started, and prednisolone 10 mg daily dose was given. After complete recovery, the patient was discharged with aspirin, clopidogrel, atorvastatin, metoprolol, losartan, isosorbide mononitrate, and nicorandil. Prednisolone 10 mg daily dose was given for five days after discharge.

Conclusion

In immediate hypersensitivity, with persistent cardiovascular instability, Kounis syndrome should be considered, and an electrocardiogram and other appropriate assessments and treatments should be initiated. Prompt management of the allergic reaction and the ACS is vital for a better outcome of Kounis syndrome.

Epirubicin-induced Kounis syndrome

BACKGROUND

Kounis syndrome is an acute coronary syndrome that appears in the setting of anaphylactic reaction or hypersensitivity. Many drugs and environmental exposures have been identified as potential offenders, and diagnosis and treatment can be challenging.

CASE PRESENTATION

A 62-year-old man with recurrent bladder cancer underwent an intra-iliac artery epirubicin injection. After the injection, he developed chest pain and a systemic allergic reaction, with electrocardiographic alterations and elevated troponin-I levels. Emergent coronary angiography showed right coronary artery spasm and no stenosis of the other coronary arteries. This reaction was considered compatible with an allergic coronary vasospasm. A diagnosis of Kounis syndrome was made.

CONCLUSIONS

Kounis syndrome is common, but a prompt diagnosis is often not possible. This case is the first to suggest that an intraarterial epirubicin injection could potentially be one of its triggers. All physicians should be aware of the pathophysiology of this condition to better recognize it and start appropriate treatment; this will prevent aggravation of the vasospastic cardiac attacks and yield a better outcome.

Hello, kitty: could cat allergy be a form of intoxication?

Background

The relationship between slow loris (Nycticebus spp.) venom (BGE protein) and the major cat allergen (Fel d 1) from domestic cat (Felis catus) is known for about two decades. Along this time, evidence was accumulated regarding convergences between them, including their almost identical mode of action.

Methods

Large-scale database mining for Fel d 1 and BGE proteins in Felidae and Nycticebus spp., alignment, phylogeny proposition and molecular modelling, associated with directed literature review were assessed.

Results

Fel d 1 sequences for 28 non-domestic felids were identified, along with two additional loris BGE protein sequences. Dimer interfaces are less conserved among sequences, and the chain 1 shows more sequence similarity than chain 2. Post-translational modification similarities are highly probable.

Conclusions

Fel d 1 functions beyond allergy are discussed, considering the great conservation of felid orthologs of this protein. Reasons for toxicity being found only in domestic cats are proposed in the context of domestication. The combination of the literature review, genome-derived sequence data, and comparisons with the venomous primate slow loris may point to domestic cats as potentially poisonous mammals.

Type I Kounis Syndrome after Protracted Anaphylaxis and Myocardial Bridge-Brief Literature Review and Case Report

The term allergic angina, introduced for the first time by Nicholas Kounis in 1991, initially referred to the coexistence of acute coronary syndromes with allergy or hypersensitivity. At present, it is believed that Kounis syndrome is a particular case of systemic disease, with multiorgan arterial involvement generated during immediate hypersensitivity reactions. Myocardial bridging (MB), a condition that can induce coronary artery spasm, has long been regarded as a benign condition. Since both pathologies are associated with arterial spasm, Kounis syndrome and MB are considered to be confounding pathologies for acute coronary syndromes, and their association is quite a rare finding. To date, there are no precise data on the epidemiology, and the population affected by Kounis syndrome seems to be highly heterogeneous. Since this is a rare disease, even less is known about possible different phenotypes, including MB overlap. We report a case of type I variant Kounis syndrome associated with MB with no evidence of coronary artery disease, occurring as late presentation, following a severe systemic reaction (anaphylaxis) induced by a Hymenoptera sting. At present, only two other cases of type I and one case of type II Kounis syndrome occurring in patients with myocardial bridging have been described.