Intraoperative anaphylaxis secondary to intraosseous gelatin administration

Reappraisal of the mechanism of cardiovascular responses to sympathomimetic amines in anaesthetised rats: dual α1-adrenoceptor and trace amine receptor mechanisms

Established dogma is that sympathomimetic amines, including β-phenylethylamine (PEA), increase blood pressure by releasing noradrenaline from sympathetic neurons. Recent evidence allowing longer contact with isolated immersed tissues indicates other mechanisms. The present study re-evaluates the mechanism of pressor responses to PEA in anaesthetised rats with longer exposure to infusions. Blood pressure and heart rate were monitored by cannulating a common carotid artery of anaesthetised male Sprague-Dawley rats. Drugs were administered by bolus doses or by 20-min infusions via a cannulated jugular vein. Increases in blood pressure by bolus doses of the α-adrenoceptor agonist, phenylephrine, were converted to depressor responses by prazosin and therefore α-adrenoceptor-mediated. Pressor responses to bolus doses of PEA were reduced. PEA infusions yielded four-phase responses: An initial increase in pressure (phase 1) blocked by prazosin was due to α-adrenoceptor vasoconstriction and a secondary fall in pressure (phase 2) due to vasodilatation by nitric oxide release. A later pressure increase (phase 3), further elevated after infusion stopped (phase 4), was not attenuated by prazosin and therefore non-adrenergic. This study showed for the first time that the sympathomimetic amine, β-phenylethylamine, increases blood pressure by two mechanisms. The established indirect sympathomimetic mechanism applies to bolus dose administration. However, with prolonged exposure to infusions, an additional slow-onset sustained non-adrenergic blood pressure increase occurs, most likely mediated via trace amine-associated receptors (TAAR-1). This response will dominate with prolonged exposures in clinical practice. These results prompt a re-evaluation of established dogma on the indirect sympathomimetic mechanisms of these amines.

Evaluating the Efficacy and Safety of Hemofence (Thorombin Cross-Linked Sodium Hyaluronate Gel Matrix) in Hemostasis for Intractable Exudative Bleeding in Spinal Surgery: A Multicenter, Randomized, Phase III Clinical Trial

OBJECTIVE

To demonstrate the noninferiority of the novel hemostatic agent, Hemofence (BMI Korea Co., Ltd., thrombin cross-linked sodium hyaluronate gel matrix) compared to the established agent, Floseal Hemostatic Matrix (Baxter, thrombin-gelatin matrix) in achieving hemostasis for spinal surgeries, with secondary objectives to assess additional efficacy and safety.

METHODS

This clinical trial was a multicenter, randomized, subject-blinded, active-controlled, parallel-group, phase 3 study. Investigational drugs were administered to the first and second bleeding sites of each participant (or only to the first site if a second site was absent), evaluating hemostasis success rate within 10 minutes and the time to achieve hemostasis. Subsequent visits were conducted for safety assessments. For noninferiority test, a 97.5% one-sided confidence interval (CI) was used; the test group was deemed noninferior if the lower limit exceeded -10%.

RESULTS

This trial showed a 97.10% success rate in the test group and 96.05% in the control group for primary efficacy. The 95% CI (-4.90% to 7.44%) confirmed the test drug's noninferiority. Time to hemostasis showed no significant difference between groups. All adverse events, adverse drug reactions, and serious adverse events were statistically similar between groups (p=1.000, p=0.243, and p=0.966, respectively).

CONCLUSION

A novel hemostatic agent, Hemofence, demonstrated an efficacy and safety profile comparable to that of Floseal.

Topical hemostatic agents in spinal surgery

Spinal surgery can be associated with significant intraoperative blood loss which may lead to various complications. As the number of patients undergoing spinal surgery increases over time, accurate and effective hemostasis becomes critically important. Despite various surgical hemostatic techniques, conventional interventions such as compression, suture, ligation, and heat-generating cautery, are not suitable for osseous and epidural venous plexus bleeding during spinal procedures. Therefore, a variety of hemostatic agents have been developed to promote hemostasis. As they differ in terms of mechanism, form, application and potential adverse reactions, it is important to understand the natural features of existing agents. Here we comprehensively review currently available topical hemostatic agents from different sources and summarize their mechanisms of action, applications, and current or potential utilization in spinal surgery. We found hemostatic agents from different sources exert hemostatic actions through different mechanisms. In addition, topical hemostatic agents play various roles in spinal surgery including as hemostatic agent, dura mater repair, drug-carrier, skin closure, and fibrosis prevention. Compressive neurological complications are the most common complications of these hemostatic agents. Therefore, optimal use in spinal environments should match their features, indications, and efficacy with clinical conditions.

Real-World Effectiveness of Gelatin-Thrombin Matrix Sealant on Blood Loss in Adolescent Idiopathic Scoliosis Patients Undergoing Posterior Spinal Fusion: An Interrupted Time Series Study

STUDY DESIGN

Retrospective cohort study with interrupted time series analysis.

OBJECTIVE

To examine the clinical effectiveness of gelatin-thrombin matrix sealant (GTMS) on blood loss reduction after adolescent idiopathic scoliosis (AIS) surgery.

SUMMARY OF BACKGROUND DATA

The real-world effectiveness of GTMS on blood loss reduction in AIS surgery has not been determined.

PATIENTS AND METHODS

The medical records of patients receiving AIS surgery were retrospectively collected during a period before GTMS approval at our institution (January 22, 2010-January 21, 2015) as well as during a postintroduction period (January 22, 2015-January 22, 2020). The primary outcomes were intraoperative blood loss, drain output over 24 hours, and total blood loss (intraoperative blood loss + drain output over 24 h). Interrupted time series analysis using a segmented linear regression model was used to estimate the effect of GTMS on blood loss reduction.

RESULTS

A total of 179 AIS patients [mean age (range): 15.4 (11-30) yr; 159 females and 20 males; 63 preintroduction patients and 116 postintroduction patients] were included. After its introduction, GTMS was used in 40% of cases. Interrupted time series analysis revealed changes of -340 mL (95% CI: -649 to -31, P = 0.03) for intraoperative blood loss, -35 mL (95% CI: -124 to 55, P = 0.44) for drain output over 24 hours, and -375 mL (95% CI: -698 to -51, P = 0.02) for total blood loss.

CONCLUSIONS

The availability of GTMS was significantly associated with reduced intraoperative and total blood loss in AIS surgery. GTMS use as needed is recommended to control intraoperative bleeding in the setting of AIS surgery.

LEVEL OF EVIDENCE

3.

Effectiveness of gelatin matrix with human thrombin for reducing blood loss in palliative decompressive surgery with posterior spinal fusion for metastatic spinal tumors

BACKGROUND

This study aimed to investigate the effect of gelatin matrix with human thrombin (GMHT) on blood loss and survival time in patients with metastatic spinal tumors treated with palliative decompression surgery with posterior spinal fusion.

METHODS

We retrospectively reviewed 67 consecutive patients with metastatic spinal tumors who underwent palliative decompression surgery with posterior spinal fusion. We compared patients in whom GMHT was not used during surgery with those in whom GMHT was used. The following baseline characteristics were evaluated: age, height, weight, sex, metastatic tumor diagnosis, medical history, use of antiplatelet drug, use of anticoagulant drug, use of NSAIDs, smoking, preoperative PLT value, preoperative APTT, preoperative PT-INR, Karnofsky Performance Status score, Charlson comorbidities index score, the percentage of patients who received perioperative chemotherapy, main tumor level, Frankel category, revised Tokuhashi score, spinal instability neoplastic score (SINS), number of fusion segments, operation time, intraoperative blood loss, drainage blood loss, red blood cell transfusion, hemoglobin level, total protein (TP), albumin values, total blood loss (TBL), hidden blood loss, postoperative bed rest and postoperative survival time. Perioperative complications were assessed.

RESULTS

Age, height, weight, sex, metastatic tumor diagnosis, medical history, use of antiplatelet drug, use of anticoagulant drug, use of NSAIDs, smoking, preoperative PLT value, preoperative APTT, preoperative PT-INR, CCI score, main level of tumors, SINS score, preoperative Tokuhashi score and number of fusion segments did not differ significantly between the two groups. Operation time, intraoperative blood loss, postoperative drainage blood loss, and TBL were significantly decreased in the group with GMHT than in the group without GMHT. The total number of perioperative complications was significantly lesser in the group with GMHT than in the group without GMHT. The median postoperative survival time was significantly longer in the GMHT group than in the group without GMHT.

CONCLUSION

GMHT should be considered a valid option for the treatment of patients with metastatic spinal tumors with a short life expectancy.

Direct intralesional n-butyl-cyanoacrylate embolization for intractable vertebral hemangioma bleeding: a salvage technique. Illustrative case

BACKGROUND

Surgical resection of vertebral hemangiomas in the setting of cord compression can be technically difficult and has the potential for life-threatening hemorrhage. The authors report a case of intraoperative direct intralesional n-butyl-cyanoacrylate embolization for intractable vertebral hemangioma bleeding.

OBSERVATIONS

A 53-year-old woman presented for repeat surgery of a residual vertebral hemangioma after a previous debulking, laminectomy, and fixation that were without problems with bleeding. The second surgery was complicated by intractable hemorrhage. Bleeding was controlled with direct intralesional n-butyl-cyanoacrylate embolization after fluoroscopy without accompanying endovascular embolization.

LESSONS

Aggressive vertebral hemangiomas should ideally be managed in centers where transarterial embolization is available. If such centers are not available or there is still intractable intraoperative bleeding despite preoperative embolization, direct intralesional embolization may be considered as a potential salvage technique.

Anaphylaxis to Excipients in Current Clinical Practice: Evaluation and Management

Excipients are the inactive ingredients in a drug or product that help to stabilize, preserve, or enhance the pharmacokinetics and bioavailability of the active ingredients. Excipient allergy is rare and hence often missed or misdiagnosed due to lack of awareness of the need to carefully review all drug ingredients. For the patient, excipient allergy can be frightening and potentially disruptive to health care delivery. This narrative review provides a clinically oriented, international, collaborative perspective on excipient allergy testing, management of future health care safety, limitations in our testing modalities, and barriers to optimal care.

Intraoperative Anaphylaxis to the Bovine Flowable Gelatin Matrix: A Report of 2 Cases

CASE

We present 2 cases of life-threatening intraoperative anaphylaxis to the bovine flowable gelatin matrix during pediatric spinal deformity surgery for kyphoscoliosis. Both patients had no known bovine or gelatin allergies. Anaphylaxis occurred shortly after pressurized injection into the first cannulated pedicle tract and was successfully treated with epinephrine, diphenhydramine, and methylprednisolone infusion. The allergic reaction was confirmed with tryptase levels and serum-specific immunoglobulin E for beef, pork, bovine collagen, and porcine collagen.

CONCLUSION

In patients with beef, pork, or gelatin intolerance, a significant atopic history or childhood vaccine reaction, preoperative allergy consultation, and testing should be performed to prevent this life-threatening complication.

Perioperative Anaphylaxis

Perioperative anaphylaxis is a potentially life-threatening and under-recognized event most commonly caused by antibiotics, neuromuscular blocking agents, dyes, latex, and disinfectants. This review provides updates in the epidemiology and pathogenesis of perioperative anaphylaxis, discusses culprit agents, and highlights the tenets of management including a comprehensive allergy evaluation.

Hidden Dangers: Recognizing Excipients as Potential Causes of Drug and Vaccine Hypersensitivity Reactions

Excipients are necessary as a support to the active ingredients in drugs, vaccines, and other products, and they contribute to their stability, preservation, pharmacokinetics, bioavailability, appearance, and acceptability. For both drugs and vaccines, these are rare reactions; however, for vaccines, they are the primary cause of immediate hypersensitivity. Suspicion for these "hidden dangers" should be high, in particular, when anaphylaxis has occurred in association with multiple chemically distinct drugs. Common excipients implicated include gelatin, carboxymethylcellulose, polyethylene glycols, and products related to polyethylene glycols in immediate hypersensitivity reactions and propylene glycol in delayed hypersensitivity reactions. Complete evaluation of a suspected excipient reaction requires detailed information from the product monograph and package insert to identify all ingredients that are present and to understand the function and structure for these chemicals. This knowledge helps develop a management plan that may include allergy testing to identify the implicated component and to give patients detailed information for future avoidance of relevant foods, drugs, and vaccines. Excipient reactions should be particularly considered for specific classes of drugs where they have been commonly found to be the culprit (eg, corticosteroids, injectable hormones, immunotherapies, monoclonal antibodies, and vaccines). We provide a review of the evidence-based literature outlining epidemiology and mechanisms of excipient reactions and provide strategies for heightened recognition and allergy testing.

Anaphylaxis after injecting a hemostatic agent containing gelatin into vertebral bone under pressure-a warning

STUDY DESIGN

Case series.

PURPOSE

The use of topical hemostatic agents is common in spinal deformity surgery. While beneficial, emerging case data shows gelatin-containing agents causing intra-operative complications. We present two patients who developed anaphylaxis after injection of these gelatin-containing hemostatic agents into the vertebral body using manual pressure. In the literature, while anaphylactic reactions associated with the use of animal-derived gelatin has been implicated; the risk of injecting these products into the closed vascular cavity of the vertebral body with subsequent embolization into systemic circulation bears emphasis. This report is to meant to make the surgical team aware of the risks of injecting hemostatic agents using manual pressure into the vertebral body and to highlight a plausible mechanism for the phenomenon.

METHODS

Two children with spinal deformity undergoing posterior spinal fusion procedures with the use of gelatin-containing hemostatic agents injected into the vertebral body through the pedicle are described.

RESULTS

Both patients had gelatin-containing hemostatic agent solution injected under manual pressure through the vertebral pedicle to prevent excessive bleeding. Anaphylaxis occurred soon thereafter, resulting in emergent cessation of the surgery and initiation of medical resuscitation. In both cases, tryptase levels obtained just after the event were elevated.

CONCLUSION

Patients with an allergy to or prior history of exposure to zoologic products undergoing spine surgery may be at risk of anaphylaxis if the gelatin-containing hemostatic agent is injected under manual pressure into the closed space of the vertebral body. This allows rapid entry into the venous circulation. We recommend that the surgeon perform a thorough history of a patient's allergies and use extreme caution when injecting these topical hemostatic products into the vertebral body.

LEVEL OF EVIDENCE

IV.

Review of topical gelatin-based haemostatic agents; an insidious culprit of intraoperative anaphylaxis?

BACKGROUND

An under-recognized complication of gelatin-based haemostatic agents is their potential to cause anaphylactic reactions. This review aims to collate and analyse case in the literature of intraoperative anaphylaxis secondary to locally applied haemostatic agents.

METHODS

An electronic search was performed on databases Medline, Embase, Pubmed and ProQuest. A total of 7671 articles were reviewed from title and abstract. After exclusion criteria and duplicates removed, 19 articles with 21 cases were included for analysis. Data extracted from each of the articles included patient demographics, haemostatic agent used, surgery type, known allergies and any objective evidence of hypersensitivity post anaphylactic episode, that is tryptase levels, IgE levels, skin prick testing.

RESULTS

Fifty-seven percent of cases involved patients <18 years of age; 57% of cases involved spinal surgery; 100% of cases displayed objective evidence of hypersensitivity (tryptase levels, bovine or porcine IgE levels, or skin prick testing). Thirty-three percent of patients had exposure preoperatively to a known agent causing anaphylaxis or allergy which would preclude the use of a gelatin-based haemostat. These products included vaccines, spam meats, red meat, Jell-O and CollaPlug. Gelatin-based haemostat agents included Floseal, Gelfoam, Surgiflo, fibrin glue, Avitene, haemofibrine sponge, topical bovine thrombin and thrombin-soaked gelatin.

CONCLUSION

Increased awareness of allergy to gelatin-based haemostats for surgical and anaesthetic is imperative, with 33% of cases having a known contraindication to gelatin-based haemostat. This review highlights important aspects in the pre-operative patient history and post-event patient investigation that could assist anaesthetists and surgeons in the prevention of future events.

Preventing iatrogenic gelatin anaphylaxis

OBJECTIVE

To assess the iatrogenic risks of gelatin allergy and identify resources for patient management.

DATA SOURCES

A literature review was performed using PubMed and public databases provided by the National Library of Medicine.

STUDY SELECTIONS

Reports of iatrogenic gelatin allergy associated with vaccines, hemostatic agents, intravenous colloids, medicinal capsules, and intraoperative surgical supplies.

RESULTS

Gelatin ingredients may not be identified by electronic medical record safeguards, and an exhaustive listing of potential iatrogenic exposures is elusive. The National Library of Medicine AccessGUDID (https://accessgudid.nlm.nih.gov/) can be a useful resource in evaluating medical devices for gelatin content. Unexpected sources of iatrogenic gelatin exposure include hemostatic agents, vascular grafts, intravascular cannulas, bone replacement implants, and emergency resuscitation fluids.

CONCLUSION

Vigilance is important within medical systems to avoid inadvertent gelatin exposure when caring for patients with gelatin allergy. Additional safeguards are needed to remove latent health care system errors that fail to prevent gelatin administration in this at-risk population.

Intraoperative anaphylaxis to gelatin-based hemostatic agents: a case report

Surgiflo Haemostatic Matrix is an absorbable gelatin matrix hemostatic material that has been widely used in various surgical operations to assist hemostasis. Nonetheless, as biologically active agents (contains porcine gelatin), there is potential for allergic reactions to these products. Here, we report the case of a 71-year-old man who had intraoperative anaphylaxis with cardiovascular events to gelatin associated with the use of a topical hemostatic agent (Surgiflo). The patient reported a history of red meat allergy and tick bites during his allergological examination after anaphylaxis. He also had high levels of specific IgE antibodies towards alpha-gal. Special consideration should be given before administering bovine- or porcine-derived gelatin products during surgery to patients with animal-related allergies, such as alpha-gal or gelatin allergy and an atopic background.

History of Hemostasis in Neurosurgery

Control of bleeding in the confined area of the skull is imperative for successful neurosurgery and the prevention of devastating complications such as postoperative hemorrhage. This paper reviews the historical evolution of methods to achieve successful hemostasis in neurosurgery from the early1800s to today. The major categories of hemostatic agents (mechanical, chemical and thermal) are delineated and discussed in chronological order. The significance of this article is in its detailed history of the kinds of hemostatic methods that have evolved with our accumulating medical and surgical knowledge, which may inform future innovations and improvements.

Gelatine matrix with human thrombin decreases blood loss in adolescents undergoing posterior spinal fusion for idiopathic scoliosis: a multicentre, randomised clinical trial

AIMS

In a multicentre, randomised study of adolescents undergoing posterior spinal fusion for idiopathic scoliosis, we investigated the effect of adding gelatine matrix with human thrombin to the standard surgical methods of controlling blood loss.

PATIENTS AND METHODS

Patients in the intervention group (n = 30) were randomised to receive a minimum of two and a maximum of four units of gelatine matrix with thrombin in addition to conventional surgical methods of achieving haemostasis. Only conventional surgical methods were used in the control group (n = 30). We measured the intra-operative and total blood loss (intra-operative blood loss plus post-operative drain output).

RESULTS

Each additional hour of operating time increased the intra-operative blood loss by 356.9 ml (p < 0.001) and the total blood loss by 430.5 ml (p < 0.001). Multiple linear regression analysis showed that the intervention significantly decreased the intra-operative (-171 ml, p = 0.025) and total blood loss (-177 ml, p = 0.027). The decrease in haemoglobin concentration from the day before the operation to the second post-operative day was significantly smaller in the intervention group (-6 g/l, p = 0.013) than in the control group.

CONCLUSION

The addition of gelatine matrix with human thrombin to conventional methods of achieving haemostasis reduces both the intra-operative blood loss and the decrease in haemoglobin concentration post-operatively in adolescents undergoing posterior spinal fusion for idiopathic scoliosis.

TAKE HOME MESSAGE

A randomised clinical trial showed that gelatine matrix with human thrombin decreases intra-operative blood loss by 30% when added to traditional surgical haemostatic methods in adolescents undergoing posterior spinal fusion for idiopathic scoliosis.

Intraoperative Anaphylactic Reaction: Is it the Floseal?

When hemodynamic or respiratory instability occurs intraoperatively, the inciting event must be determined so that a therapeutic plan can be provided to ensure patient safety. Although generally uncommon, one cause of cardiorespiratory instability is anaphylactic reactions. During anesthetic care, these most commonly involve neuromuscular blocking agents, antibiotics, or latex. Floseal is a topical hemostatic agent that is frequently used during orthopedic surgical procedures to augment local coagulation function and limit intraoperative blood loss. As these products are derived from human thrombin, animal collagen, and animal gelatin, allergic phenomenon may occur following their administration. We present 2 pediatric patients undergoing posterior spinal fusion who developed intraoperative hemodynamic and respiratory instability following use of the topical hemostatic agent, Floseal. Previous reports of such reactions are reviewed, and the perioperative care of patients with intraoperative anaphylaxis is discussed.

Kounis syndrome: an update on epidemiology, pathogenesis, diagnosis and therapeutic management

Kounis syndrome has been established as a hypersensitivity coronary disorder induced by various conditions, drugs, environmental exposures, foods and coronary stents. Allergic, hypersensitivity, anaphylactic and anaphylactoid reactions are associated with this syndrome. Vasospastic allergic angina, allergic myocardial infarction and stent thrombosis with occluding thrombus infiltrated by eosinophils and/or mast cells constitute are the three reported, so far, variants of this syndrome. Apart from coronary arteries, it affects the cerebral and mesenteric arteries. Its manifestations are broadening and its etiology is continuously increasing. Kounis syndrome is a ubiquitous disease which 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 seems to be not a rare disease but an infrequently diagnosed clinical entity which has revealed that the same mediators released from the same inflammatory cells are also present and in acute coronary events of non allergic 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, awareness of etiology, epidemiology, pathogenesis and clinical manifestations seems to be important for its prognosis, diagnosis, treatment, prevention.

Perioperative anaphylaxis: diagnosis, evaluation, and management

Perioperative anaphylaxis can occur during or after surgery and can have life-threatening consequences. As anesthesia protocols become more complex and incorporate multiple agents to regulate physiologic processes intraoperatively, perioperative anaphylaxis is becoming increasingly recognized. The allergist should obtain detailed records from the anesthesiologist in order to perform appropriate testing to identify the likely causative agents. Testing should ideally be performed 4 to 6 weeks after the reaction to account for a refractory period after mast cell activation. This article includes 2 cases of perioperative anaphylaxis and reviews the historical elements that must be considered after a reaction has occurred.

Injectable gelatin used as hemostatic agent to stop pedicle bleeding in long deformity surgical procedures: does it embolize?

STUDY DESIGN

Prospective porcine animal model.

OBJECTIVE

Determine if injecting FloSeal into pedicles for hemostasis causes emboli.

SUMMARY OF BACKGROUND DATA

Bleeding from spinal deformity cases can be substantial, especially when surgical procedures involve bilateral fixation at multiple segments. It is not unusual to observe hemorrhage from vascular pedicles during each step of pedicle screw tract preparation. When multiple fixation points are required, blood loss can be excessive. To minimize estimated blood loss and associated morbidity, surgeons have injected liquefied gelatin into pedicles after drilling, palpating, and/or tapping. FloSeal is one of the most popular commercially available injectable agents and we sought to investigate the potential for embolization when used as an intrapedicular hemostatic agent.

METHODS

Two adult minipigs were anesthetized and underwent sequential bilateral pedicle cannulation from T-spine to sacrum. At every level, tracts were cannulated, palpated, and tapped. In every tract, FloSeal was injected into each pedicle until back pressure was detected on the syringe or to a maximum volume of 2 mL, then pedicle screws were inserted. The right ventricular outflow tract was visualized real time using transesophageal echocardiography. Postmortem evaluation of heart and lungs was performed.

RESULTS

FloSeal injected into pedicles caused a consistent large showering of the right ventricular outflow tract in both pigs as visualized on intraoperative transesophageal echocardiography. A second large showering occurred during screw insertion after FloSeal was injected. Microscopic examination of lungs clearly identified amphophilic amorphous material in many small vessels consistent with FloSeal.

CONCLUSION

This study suggests caution when injecting gelatin hemostatic agents into pedicles to stop bleeding during spinal surgery as we saw clear evidence of fat and gelatin emboli when used in this animal model. Further investigation into how to minimize this embolic showering may help the cardiopulmonary at risk patient who requires spinal surgery, especially when multiple points of pedicle screw fixation are used.

LEVEL OF EVIDENCE

N/A.

Foods, Drugs and Environmental Factors: Novel Kounis Syndrome Offenders

Kounis syndrome is hypersensitivity coronary disorder induced by various types of environmental exposures, drugs, conditions and stents. Allergic, hypersensitivity, anaphylactic and anaphylactoid reactions are associated with this syndrome. The disorder manifests as coronary spasms, acute myocardial infarction and stent thrombosis and affects the cerebral and mesenteric as well as coronary arteries. Importantly, its manifestations are broad and its etiology is continuously increasing. Recently, a variety of unusual etiologies have been reported including Anisakis simplex, scombroid syndrome, the use of Gelofusin or ultrasound contrast agents, kiwifruit, fly bites, and bee stings. Furthermore, losartan and the paradox of corticosteroid allergy have been implicated as possible causes. Although not rare, Kounis syndrome is infrequently diagnosed. Therefore, awareness of its etiology, manifestations and pathophysiology is important for providing the proper diagnosis and treatment and determining prognosis.