Anaphylaxis: A 2023 practice parameter update.

This practice parameter update focuses on 7 areas in which there are new evidence and new recommendations. Diagnostic criteria for anaphylaxis have been revised, and patterns of anaphylaxis are defined. Measurement of serum tryptase is important for diagnosis of anaphylaxis and to identify underlying mast cell disorders. In infants and toddlers, age-specific symptoms may differ from older children and adults, patient age is not correlated with reaction severity, and anaphylaxis is unlikely to be the initial reaction to an allergen on first exposure. Different community settings for anaphylaxis require specific measures for prevention and treatment of anaphylaxis. Optimal prescribing and use of epinephrine autoinjector devices require specific counseling and training of patients and caregivers, including when and how to administer the epinephrine autoinjector and whether and when to call 911. If epinephrine is used promptly, immediate activation of emergency medical services may not be required if the patient experiences a prompt, complete, and durable response. For most medical indications, the risk of stopping or changing beta-blocker or angiotensin-converting enzyme inhibitor medication may exceed the risk of more severe anaphylaxis if the medication is continued, especially in patients with insect sting anaphylaxis. Evaluation for mastocytosis, including a bone marrow biopsy, should be considered for adult patients with severe insect sting anaphylaxis or recurrent idiopathic anaphylaxis. After perioperative anaphylaxis, repeat anesthesia may proceed in the context of shared decision-making and based on the history and results of diagnostic evaluation with skin tests or in vitro tests when available, and supervised challenge when necessary.

Standardized guidelines for Africanized honeybee venom production needed for development of new apilic antivenom.

Africanized bees have spread across the Americas since 1956 and consequently resulted in human and animal deaths attributed to massive attacks related to exposure from Argentina to the USA. In Brazil, more than 100,000 accidents were registered in the last 5 years with a total of 303 deaths. To treat such massive attacks, Brazilian researchers developed the first specific antivenom against Africanized honey bee sting exposure. This unique product, the first of its kind in the world, has been safely tested in 20 patients during a Phase 2 clinical trial. To develop the antivenom, a standardized process was undertaken to extract primary venom antigens from the Africanized bees for immunization of serum-producing horses. This process involved extracting, purifying, fractionating, characterizing, and identifying the venom (apitoxin) employing mass spectrometry to generate standardized antigen for hyperimmunization of horses using the major toxins (melittin and its isoforms and phospholipase A2). The current guide describes standardization of the entire production chain of venom antigens in compliance with good manufacturing practices (GMP) required by regulatory agencies. Emphasis is placed upon the welfare of bees and horses during this process, as well as the development of a new biopharmaceutical to ultimately save lives.

Whole sporozoite immunization with Plasmodium falciparum strain NF135 in a randomized trial.

BACKGROUND: Whole sporozoite immunization under chemoprophylaxis (CPS regime) induces long-lasting sterile homologous protection in the controlled human malaria infection model using Plasmodium falciparum strain NF54. The relative proficiency of liver-stage parasite development may be an important factor determining immunization efficacy. Previous studies show that Plasmodium falciparum strain NF135 produces relatively high numbers of large liver-stage schizonts in vitro. Here, we evaluate this strain for use in CPS immunization regimes. METHODS: In a partially randomized, open-label study conducted at the Radboudumc, Nijmegen, the Netherlands, healthy, malaria-naïve adults were immunized by three rounds of fifteen or five NF135-infected mosquito bites under mefloquine prophylaxis (cohort A) or fifteen NF135-infected mosquito bites and presumptive treatment with artemether/lumefantrine (cohort B). Cohort A participants were exposed to a homologous challenge 19 weeks after immunization. The primary objective of the study was to evaluate the safety and tolerability of CPS immunizations with NF135. RESULTS: Relatively high liver-to-blood inocula were observed during immunization with NF135 in both cohorts. Eighteen of 30 (60%) high-dose participants and 3/10 (30%) low-dose participants experienced grade 3 adverse events 7 to 21 days following their first immunization. All cohort A participants and two participants in cohort B developed breakthrough blood-stage malaria infections during immunizations requiring rescue treatment. The resulting compromised immunizations induced modest sterile protection against homologous challenge in cohort A (5/17; 29%). CONCLUSIONS: These CPS regimes using NF135 were relatively poorly tolerated and frequently required rescue treatment, thereby compromising immunization efficiency and protective efficacy. Consequently, the full potential of NF135 sporozoites for induction of immune protection remains inconclusive. Nonetheless, the high liver-stage burden achieved by this strain highlights it as an interesting potential candidate for novel whole sporozoite immunization approaches. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov under identifier NCT03813108.

Fire ant Immunotherapy with inteRvals Extended to 12 weekS: The FIRES study.

BACKGROUND: There are no studies describing 12-week extended maintenance interval (EMI) immunotherapy (IT) efficacy in preventing anaphylaxis to imported fire ant (IFA) stings. OBJECTIVE: The purpose of this study was to determine the safety and efficacy of 12-week maintenance intervals in patients treated with IFA IT. METHODS: After a minimum of 3 months of conventional maintenance interval IT and verification of baseline efficacy, adults with IFA hypersensitivity were prospectively enrolled and extended their maintenance doses to 6-, 8-, and 12-week intervals. Efficacy was confirmed by means of an annual IFA sting challenge. RESULTS: A total of 25 patients initiated EMI. The severity of their initial systemic reactions was mild in 8 patients (32%), moderate in 10 patients (40%), and severe in 7 patients (28%). Maintenance IT duration at trial entry was less than 3 years in 18 patients (mean 11 months; range 3-28 months), 3 to 5 years in 4 patients (mean 46 months; range 36-57 months), and greater than 5 years in 5 patients (mean 111 months; range 67-197 months). The treatment cohort did not experience systemic reactions to extended interval injections, cluster refill injections, field stings, or sting challenges. CONCLUSION: This prospective longitudinal cohort study revealed that in adults 18 years old or older who have received at least 3 months of maintenance dose IFA-whole body extract IT with proven efficacy, extension to a 12-week EMI is a safe effective treatment option. The benefits of EMI include a reduced number of injections, clinic visits, and lapses in maintenance IT.

Are insect bites responsible for the rise in summer flucloxacillin prescribing in United Kingdom general practices?

BACKGROUND: Insect bite inflammation may mimic cellulitis and promote unnecessary antibiotic usage, contributing to antimicrobial resistance in primary care. We wondered how general practice clinicians assess and manage insect bites, diagnose cellulitis, and prescribe antibiotics. METHOD: This is a Quality Improvement study in which 10 general practices in England and Wales investigated patients attending for the first time with insect bites between April and September 2021 to their practices. Mode of consultation, presentation, management plan, and reattendance or referral were noted. Total practice flucloxacillin prescribing was compared to that for insect bites. RESULTS: A combined list size of 161,346 yielded 355 insect bite consultations. Nearly two-thirds were female, ages 3-89 years old, with July as the peak month and a mean weekly incidence of 8 per 100,000. GPs still undertook most consultations; most were phone consultations, with photo support for over half. Over 40% presented between days 1 and 3 and common symptoms were redness, itchness, pain, and heat. Vital sign recording was not common, and only 22% of patients were already taking an antihistamine despite 45% complaining of itch. Antibiotics were prescribed to nearly three-quarters of the patients, mainly orally and mostly as flucloxacillin. Reattendance occurred for 12% and referral to hospital for 2%. Flucloxacillin for insect bites contributed a mean of 5.1% of total practice flucloxacillin prescriptions, with a peak of 10.7% in July. CONCLUSIONS: Antibiotics are likely to be overused in our insect bite practice and patients could make more use of antihistamines for itch before consulting.

It can be difficult to know if redness, heat, swelling, and pain from insect bites are due to inflammation or infection. Prescribing unnecessary antibiotics may result in germs becoming resistant to antibiotics when needed. Ten general practices in England and Wales investigated their management of insect bites in the 6 months of April to September 2021 inclusive. There were 355 bites; women presented more often than men, and ages were from 3 to 89 years old, half of them were 30­69 years old. People mainly consulted their GP by phone with photos of their bites. Key symptoms were redness, itchness, heat, and pain. More people had itch than were taking antihistamines or using steroid cream. Most people (nearly 7 out of 10) were prescribed an oral antibiotic, usually flucloxacillin, which accounted for about 5% of total flucloxacillin prescribed in the practices. Only 2 in 100 people needed further hospital care. It is likely that general practice clinicians are over-using antibiotics for insect bites and that home management before seeking medical help with painkillers, antihistamines, and steroid creams could be used more. Now that we have baseline data, there is a need to set up studies to prove that these reduce antibiotic usage.

Effectiveness and safety of a cream product containing zinc oxide for alleviating mosquito bite symptoms.

BACKGROUND: People frequently experience discomfort with immediate wheal, delayed papules, and pruritus from mosquito bites. A topical cream product containing zinc oxide is commercially available for the management of insect bites, but there has been no published evidence for its effectiveness and safety. AIMS: To evaluate the effectiveness and safety of this product in symptoms caused by mosquito bites. METHODS: An open-label, controlled study was performed on 41 healthy participants. All subjects received Aedes aegypti mosquito bites on the forearm. Then test product was randomly applied to the bitten areas of the left or right arm. The other arm was left untreated (control). The onset of pruritus relief was noted. The severity of pruritus was assessed using a visual analogue scale (VAS), ranging from 0 mm (no pruritus) to 100 mm (severe pruritus), and a 4-point pruritus score (0 = none; 1 = mild, not affecting normal activities; 2 = moderate, affecting normal activities to some extent; 3 = severe, significantly affecting activities) at four time points: 15 minutes after the mosquito bite (baseline), as well as 1 hour, 24 hours, and 48 hours after initiating treatment. The size of the bite reaction lesion was also measured at all time points. Any local cutaneous adverse reactions observed during the study were documented. RESULTS: The onset of pruritus relief in the treated group (25 ± 21.7 minutes) was significantly faster compared to the untreated group (118.7 ± 304.8 minutes). The reduction in VAS score at 1 hour was significantly greater in the product group (30.5 ± 16.22) compared to the control group (14.9 ± 9.9). Moreover, there was a significant difference in the reduction of pruritus score at 1 hour, with the product group (1.1 ± 0.5) showing a higher reduction compared to the control group (0.3 ± 0.4). However, there was no significant difference in the reduction of bite lesion size between the two groups. Throughout the study, no adverse events were reported. CONCLUSION: Our preliminary findings indicate that the product effectively reduces pruritus caused by mosquito bites but does not have a significant impact on the size of the bite lesions. The product was found to be safe and may be an option for managing mosquito bites pruritus.

The Lights and the Shadows of Controlled Sting Challenge With Hymenoptera.

Hymenoptera venom immunotherapy (VIT) is effective for protecting individuals with systemic allergic reactions caused by Hymenoptera stings. The need for a tool that shows the degree of protection afforded by VIT and the lack of useful biomarkers have made the sting challenge test (SCT) the gold standard for this disorder, although its use has both lights and shadows. SCT with Hymenoptera involves causing a real sting in a patient diagnosed with allergy to the venom of the stinging insect and who is undergoing treatment with specific immunotherapy. In Spain, SCT is included in the list of services offered by some hospitals and forms part of their daily clinical practice. This review aims to analyze the strengths and weaknesses of this test and to describe the standardized procedure and necessary resources, based on the experience of a group of Spanish experts and a review of the literature.

Novel Use of Topical Ivermectin for the Prevention of Facial Insect Bites.

Options to prevent facial insect bites while sleeping are limited. Patients may prefer to avoid facial application of potentially neurotoxic insect repellants. Non-toxic “natural” repellants have limited efficacy, and netting may not be well-tolerated. Nightly facial application of 1% topical ivermectin (IVM) cream completely prevented overnight bites in 2 patients, both of whom reported recurrent bites after discontinuation, and a return to complete bite prevention after IVM resumption. Topical IVM may be an alternative facial mosquito bite prevention modality. J Drugs Dermatol. 2022;21(8):906-907. doi:10.36849/JDD.6432.

Venom immunotherapy and difficulties encountered before and during immunotherapy: Double sensitization, systemic reactions, treatment with omalizumab, and high dose VIT.

BACKGROUND: Venom immunotherapy (VIT) is the most effective treatment method to prevent recurrent systemic reactions to Hymenoptera stings. In this study, the demographic characteristics of VIT patients, the success rates of VIT, the difficulties we encountered during VIT, and solutions for these difficulties in our clinic were presented. METHODS: We retrospectively analyzed patients with venom allergy who applied venom immunotherapy between 2013- 2020. Data on age, gender, Hymenoptera species with the first reaction, grade of the reaction, beekeeping history, skin prick and specific IgE and component results, double sensitization, blood groups, and reactions with VIT and/or sting during built-up and maintenance periods were recorded. RESULTS: A total of 73 patients were enrolled in the study. The median time from the first sting reaction to the application to the allergy outpatient clinic was 12 (0.5-24) months. The first sting reaction of 38 (52.1%) of the patients was with honey bees, and 24 (32.9%) were with wasps. Double positivity was present in 29 (40%) of the patients in prick results and 26 (36%) serologically. There was no correlation between the severity of first reactions and Apis Mellifera or Vespula prick diameters (p = 0.643; r = -0.056; p = 0.462; r = 0.089, respectively). High-dose VIT was administered to 4 patients. Omalizumab has been used as an alternative agent to achieve the maintenance dose in 2 patients with frequent systemic reactions during VIT. DISCUSSION: Most patients were able to tolerate VIT. Double positivity is one of the most common difficulties before VIT. In patients who develop systemic reactions in the VIT maintenance phase, a maintenance dose increase should be considered in the maintenance phase. Adding omalizumab does not seem to be a permanent solution in patients who develop a severe systemic reaction.

Blackfly fever and dermatitis caused by Simulium kiritshenkoi: a human case report in Iran.

BACKGROUND: Besides the considerable role of blackflies to the transmission of many disease agents, these flies considered as annoying biting pests of wildlife, livestock, poultry, and humans. There are few literature reports of blackfly fever following Simulium spp. This study describes a case of blackfly fever and dermatitis following blackflies numerous bites in Iran. CASE PRESENTATION: The present report describes a 25-year-old man that was attacked by numerous flies while fishing and camping near Namrood river in Firuzkuh County, Tehran Province, Iran. Pruritic dermatitis with marked edema appeared mainly on the hands and legs and subsequently, the patient's condition worsened with swollen lymph nodes, joints aching, and 40 °C fever. The patient's clinical signs and symptoms were alleviated by injection of intramuscular Dexamethasone Phosphate (DEXADIC®) 8 mg/2 ml after 24 h. CONCLUSIONS: This study reported a human case with blackfly fever and dermatitis following numerous bites of Simulium kiritshenkoi, for the first time in Iran.

Venom allergy and knowledge about anaphylaxis among beekeepers and their families.

BACKGROUND: Beekeepers and their families are at an increased risk of life-threatening anaphylaxis due to recurrent bee-sting exposures. OBJECTIVE: The aim of this study is to evaluate the demographic features, previous history of anaphylaxis among beekeepers and their family members, and their knowledge about the symptoms and management of anaphylaxis. METHODS: A standardized questionnaire was administered to beekeepers during the 6th International Beekeeping and Pine Honey Congress held in 2018, in Mugla, Turkey. Additionally, food-service staff from restaurants were surveyed as an occupational control group about their knowledge about anaphylaxis. RESULTS: Sixty-nine beekeepers (82.6% male, mean age 48.4±12.0 years) and 52 restaurant staff (46.2% male, mean age 40.5±10.0 years) completed the questionnaire. Awareness of the terms 'anaphylaxis' and 'epinephrine auto-injector' among the beekeepers were 55.1% and 30.4% and among the restaurant staff were 23.1% and 3.8%, respectively. Of the beekeepers, 74% were able to identify the potential symptoms of anaphylaxis among the given choices; 2.9% and 5.8% reported anaphylaxis related to bee-stings in themselves and in their family members, respectively. None of the restaurant staff had experienced or encountered anaphylaxis before but 3.8% of their family members had anaphylaxis and those reactions were induced by drugs. CONCLUSION: It is essential that implementation of focused training programs about anaphylaxis symptoms and signs as well as practical instructions of when and how to use an epinephrine auto-injector will decrease preventable morbidities and mortalities due to bee-stings in this selected high-risk population of beekeepers and their family members, as well as other fieldworkers under risk.

Ant Bites Conjunctival Tissue: The ABCs of Removing an Ocular Ant Foreign Body.

BACKGROUND: A variety of insect-related ocular injuries have been reported in the literature. However, no reports have been published documenting injuries resulting from exposure of the ocular surface to ants. This is surprising, given the relatively ubiquitous presence of ants. This is the first known case report to describe various techniques utilized in the removal of ants from the ocular surface. CASE REPORT: This case report details the presentation of a distressed 24-year-old woman who presented to the Emergency Department with an ocular foreign body associated with pain and increased lacrimation. She was identified to have an ant adherent to her conjunctiva. Various techniques of removal were performed, with the ant finally removed without any trauma to underlying tissues. CONCLUSION: This is the first case report to detail various techniques utilized in the removal of ants from the ocular surface, and discusses salient features that treating physicians should be aware of in managing patients presenting with ant bites.

Eosinophilic dermatoses.

Eosinophilic dermatoses are a heterogeneous group of diseases, characterized by an eosinophil-rich infiltrate and/or degranulation of eosinophils. Blood eosinophilia may be an associated feature. Typical, albeit not specific histological findings include 'flame figures', which are caused by the accumulation of cationic proteins released by eosinophils and subsequent collagen denaturation. "Classic" eosinophilic dermatoses include eosinophilic cellulitis (Wells syndrome), granuloma faciale, eosinophilic fasciitis (Shulman syndrome) and eosinophilic folliculitis (Ofuji disease). In addition, there is a multitude of skin diseases that present with varying degrees of eosinophilic infiltration. These include atopic dermatitis, bullous pemphigoid, urticaria, allergic contact dermatitis, prurigo nodularis, arthropod bite reaction, parasitic infections, and drug hypersensitivity. Even though these disorders share a common characteristic (tissue eosinophilia), they differ greatly in their clinical presentation.

A honey bee can threat ear: Sudden sensorineural hearing loss.

Sudden sensorineural hearing loss is an otologic emergency. Many etiological factors can lead to this pathology. Honey bee (Apis mellifera) sting may lead to local and systemic reactions due to sensitization of the patient. In this paper we described a sudden sensorineural hearing loss occurred after honey bee sting.

Oral Mucosal Envenomation of an Infant by a Puss Caterpillar.

The term "puss caterpillar" describes the larva of at least two Megalopygidae species common to North America. Accidental contact with the hairs (setae) is intensely painful, and serious systemic effects have been reported. We describe the envenomation of an infant through the face and oral mucosa, resulting in severe discomfort, limited oral intake, and vomiting, but no other untoward effects.

Severe Hemorrhagic Syndrome After Lonomia Caterpillar Envenomation in the Western Brazilian Amazon: How Many More Cases Are There?

Contact with Lonomia caterpillars can cause a hemorrhagic syndrome. In Brazil, Lonomia obliqua and Lonomia achelous are known to cause this venom-induced disease. In the Brazilian Amazon, descriptions of this kind of envenomation are scarce. Herein, we report a severe hemorrhagic syndrome caused by Lonomia envenomation in the Amazonas state, Western Brazilian Amazon. The patient showed signs of hemorrhage lasting 8 days and required Lonomia antivenom administration, which resulted in resolution of hemorrhagic syndrome. Thus, availability of Lonomia antivenom as well as early antivenom therapy administration should be addressed across remote areas in the Amazon.

Residual Effectiveness of Permethrin-Treated Clothing for Prevention of Mosquito Bites Under Simulated Conditions.

Biological hazards such as exposure to ticks and mosquitoes can affect health. Permethrin-treated clothing is available to the public. We don't currently understand, however, the effects of environmental factors such as fabric type, washing, sunlight, and temperature on permethrin content in treated clothing with respect to mosquito knockdown and mortality. We evaluated the extent to which fabric type (100% cotton denim jeans, 100% polyester work shirt, 35% cotton/65% polyester work shirt), light exposure (0 or 100%), temperature (18 °C, 32 °C), and number of washes (0, 3, 12, 36) affected mosquito knockdown 2 hours post-exposure, mosquito mortality 24 hours post-exposure, and permethrin content. All fabrics used in this study were treated with permethrin at a concentration of 125 µg/cm2. Denim fabric having no washes and no light exposure showed the highest amount of permethrin. Washing and light exposure significantly reduced the ability of permethrin-treated fabrics to induce mosquito knockdown and/or mortality under the simulated conditions used for this test. Temperatures tested did not affect permethrin content or mosquito knockdown and mortality. Long-lasting impregnation of uniforms protects against mosquito bites under simulated laboratory conditions. Employers and employees should consider the use of permethrin-impregnated clothing and uniforms in addition to daily repellent sprays.

Kounis syndrome: a stinging case of ST-elevation myocardial infarction.

Kounis syndrome is not a rare but an infrequently diagnosed non-thrombogenic cause of angina or myocardial infarction triggered by the release of inflammatory mediators following an allergic or anaphylactic reaction. This so-called "allergic angina" is seen in the setting of anaphylactic reactions and is believed to be due to mast cell release causing coronary vasospasm. The treatment of such cases is often with epinephrine, which has also been described in the literature as another rare cause of coronary vasospasm. We present a case of Kounis syndrome seen in a 46 year-old male who suffered two bee stings while landscaping in his yard. He developed an anaphylactic reaction and was promptly treated with IM epinephrine injection by paramedics at arrival and developed marked ST elevations on EKG in the inferior leads with reciprocal ST depressions in the anterior leads. His troponin peaked at 13 ng/mL and tryptase level was 15 ng/mL (normal <10 ng/mL). Coronary catheterisation showed non-diseased coronary arteries and a normal ejection fraction without evidence of vasospasm. He was afterwards treated with an epinephrine drip for distributive shock. Interestingly this syndrome was not provoked when re-challenged with this therapy, suggestive of an allergic reaction rather than epinephrine as the aetiology of his presumed vasospasm. This patient's ST segment elevation and troponin elevation was due to Kounis syndrome. Awareness that anaphylactic reactions can lead to Kounis syndrome can lead to prompt appropriate treatment for this life threatening condition.

Secondary hemophagocytic lymphohistiocytosis (HLH) from a presumed brown recluse spider bite.

Systemic loxoscelism is a rare complication after Loxosceles reclusa (brown recluse spider) envenomation. Loxosceles venom contains pro-inflammatory proteins, which have been shown to be elevated in patients with hemophagocytic lymph histiocytosis. We present a case of a 10-year-old male that developed presumed systemic loxoscelism, secondary hemophagocytic lymphohistiocytosis with hepatic dysfunction and renal failure. He was treated with dexamethasone and made a full recovery.