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A male infant presented with swelling of the left leg and fever. Over the next 2 days, the area developed fasciitis extending to the left thigh, abdomen, and lower chest. Meanwhile, the parents found a giant brown spider within the infant’s cot belonging to the genusLoxosceles, otherwise called the brown recluse spider. The dermo-myonecrosis progressed to deeper tissues involving the lung parenchyma requiring invasive ventilation. CT of the thorax showed multiple pneumatoceles, and lung biopsy showed alveolar necrosis. The infant was treated with intravenous antibiotics and corticosteroids. We drained the pneumothoraces by thoracostomy and insertion of intercostal drainage tubes. The infant required respiratory support initially by conventional ventilation, which was escalated to high-frequency oscillatory ventilation. He had refractory hypoxaemia and died. This is the first fatal case of acute spider envenomation described in India. Spider envenomation must be considered in patients with sudden onset, rapidly progressive necrotising fasciitis unresponsive to antibiotic therapy.

We present the case of a 32-year-old male patient hospitalized during the COVID-19 pandemic because of a Brown spider bite on his lower lip. The Brown spider accident occurred in southern Brazil; at hospital admission, the patient presented on his lip: edema, pustules, necrotic regions, and ulcerations. The patient complained of lower back pain, fever and dyspnea. Laboratory tests showed monocytosis, leukocytosis, neutrophilia, increased D-dimer levels, C-reactive protein, glutamate-pyruvate transaminase, delta bilirubin, creatine phosphokinase, procalcitonin, and fibrinogen. The patient was hospitalized and a multi-professional team carried out the treatment. The medical team diagnosed loxoscelism with moderate changes. The dentist treated the oral cavity. The patient began to develop nausea, vomiting, and desaturation episodes during hospitalization. A computed tomography of the chest was performed, which showed signs of viral infection. The RT-PCR test for COVID-19 was positive. The systemic conditions worsened (renal dysfunction, systemic inflammatory response, pulmonary complications). This condition may have resulted from the association of the two diseases (loxoscelism and COVID-19), leading to the patient's death. This case illustrates the difficulties and risks in treating patients with venomous animal accidents during the pandemic, and the importance of a multi-professional team in treating such cases.

Made available in DSpace on 2022-05-01T09:47:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Universidade Federal do Paraná Fundação Araucária Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Accidents involving Brown spiders are reported throughout the world. In the venom, the major toxins involved in the deleterious effects are phospholipases D (PLDs). In this work, recombinant mutated phospholipases D from three endemic species medically relevant in South America (Loxosceles intermedia, L. laeta and L. gaucho) were tested as antigens in a vaccination protocol. In such isoforms, key amino acid residues involved in catalysis, magnesium-ion coordination, and binding to substrates were replaced by Alanine (H12A-H47A, E32A-D34A and W230A). These mutations eliminated the phospholipase activity and reduced the generation of skin necrosis and edema to residual levels. Molecular modeling of mutated isoforms indicated that the three-dimensional structures, topologies, and surface charges did not undergo significant changes. Mutated isoforms were recognized by sera against the crude venoms. Vaccination protocols in rabbits using mutated isoforms generated a serum that recognized the native PLDs of crude venoms and neutralized dermonecrosis and edema induced by L. intermedia venom. Vaccination of mice prevented the lethal effects of L. intermedia crude venom. Furthermore, vaccination of rabbits prevented the cutaneous lesion triggered by the three venoms. These results indicate a great potential for mutated recombinant PLDs to be employed as antigens in developing protective vaccines for Loxoscelism. Department of Cell Biology Federal University of Paraná (UFPR) Production and Research Center of Immunobiological Products (CPPI) State Department of Health Veterinary Hospital Federal University of Paraná (UFPR) Department of Structural Molecular Biology and Genetics State University of Ponta Grossa (UEPG) Multiuser Center for Biomolecular Innovation Departament of Physics Universidade Estadual Paulista (UNESP) Multiuser Center for Biomolecular Innovation Departament of Physics Universidade Estadual Paulista (UNESP) Universidade Federal do Paraná: 02/2020 Universidade Federal do Paraná: 04/2019 Fundação Araucária: 057/2017 CNPq: 303868/2016-3 CNPq: 408633/2018-2

We describe a case of myocarditis associated with a brown recluse spider bite in a 31-year-old man. Cardiac magnetic resonance revealed late gadolinium enhancement in the lateral wall and inferior wall. There was also regional elevation of the myocardial T2 and extracellular volume indicative of myocardial edema. (Level of Difficulty: Intermediate.), Graphical abstract

Loxosceles reclusa, or brown recluse spider, is a harmful household spider whose habitat extends throughout the Midwest in the USA and other regions in the world. The pheromones and other biomolecules that facilitate signaling for brown recluses and other spider species are poorly understood. A rapid and sensitive method is needed to analyze airborne spider signaling biomolecules to better understand the structure and function of these biochemicals in order to control the population of the spiders. In this study, we developed a novel headspace solid-phase microextraction (HS-SPME)-GC/MS method to analyze potential pheromones and biomolecules emitted by the brown recluse spider. The method is highly selective and sensitive for biomolecule identification and quantification from a single live spider. Using this novel non-destructive HS-SPME-GC/MS technique, we identified 11 airborne biomolecules, including 4-methylquinazoline, dimethyl sulfone, 2-methylpropanoic acid, butanoic acid, hexanal, 3-methylbutanoic acid, 2-methylbutanoic acid, 2,4-dimethylbenzaldehyde, 2-phenoxyethanol, and citral (contains both isomers of neral and geranial). Some of these airborne biomolecules were also reported as semiochemicals associated with biological functions of other spiders and insects. The method was also applied to study the airborne biochemicals of Plectreurys tristis, another primitive hunting spider with a poor web, enabling quantitation of the same compounds and demonstrating a difference in signaling molecule concentrations between the two species. This method has potential application in the study of pheromones and biological signaling in other species, which allows for the possibility of utilizing attractant or deterrent functions to limit household populations of harmful species.

The laeta species group is the main source of Loxosceles species in Chile, a genus of medical importance due to the cytotoxic properties of its venom and the synanthropic habits of its dominant spe...

An ocular malformation is described for the first time in the genus Loxosceles, specifically in a female of Loxosceles surca Gertsch. The specimen was collected at 3,540 m.a.s.l. in Tarapaca Region, Chile. It is the first record for this family and the first case of teratology described for spiders in this country

Loxoscelism is the clinical problem produced by the bite of a spider of the genus Loxosceles. The most severe presentation is systemic loxoscelism that can compromise the patient's life if it is not diagnosed and treated in time. There are no reports about how it presents in patients with an epilepsy diagnosis. We present the case of a 28-year-old male patient, with a prior history of epilepsy in treatment with anticonvulsants. He developed systemic loxoscelism after a spider bite in the posterior middle third of the right arm. However, the patient did not develop seizures despite the unfavourable course of his clinical symptoms.

Objectives Injuries resulting from contact with animals are a significant public health concern. This study quantifies and updates nonfatal bite and sting injuries by noncanine sources using the most recent data available (2011-2015) from the National Electronic Injury Surveillance System-All Injury Program with the purpose of using these updates to better understand public health consequences and prevention techniques. Increased rates of bites and stings can be expected in this study's time frame, possibly caused by the increasing human population expanding into animal territories, as well as changes in animal geographic distribution and pet ownership. Methods The National Electronic Injury Surveillance System-All Injury Program is an ongoing nationally representative surveillance system used to monitor all types and causes of injuries treated in US hospital emergency departments (EDs). Cases were coded by trained hospital coders using information from medical records on animal sources of bite and sting injuries being treated. Data from 2011-2015 were weighted to produce national annualized estimates, percentages, and rates based on the US population. Results An estimated 1.17 million people visited EDs for noncanine bite and sting injuries annually. This translates to a rate of 371.3/100,000 people. Insects accounted for 71.0% of noncanine bite and sting injuries, followed by arachnids (19.2%) and mammals (7.8%). The estimated annual total lifetime medical and work cost of unintentional noncanine injuries was $5,755,581,000. Conclusions Various sources of bite and sting injuries had an outsized effect on injury rates and identify potential areas of focus for education and prevention programs to reduce the burden of these injuries on health and healthcare costs. The study describes the diversity of animal exposures based on a national sample of EDs. Noncanine bite and sting injuries significantly affect public health and healthcare resources. Priorities can be focused on animal sources with the most impact on bite and sting injury rates, healthcare costs, and disease burden.

Background: Brown recluse spider (BRS) (Loxosceles reclusa) envenomation can cause local dermonecrotic lesions, constitutional symptoms, and potentially fatal hemolysis (i.e., cutaneous-hemolytic l...

Spiders have long been admired for the beauty of their webs. They are celebrated in popular culture as well as in medical eponyms. This contribution provides the historical background for three spider-related eponyms: nevus araneus (spider angioma), arachnodactyly, and the arachnoid mater. Nevus araneus was first named and described by Sir Erasmus Wilson in 1842. Arachnodactyly was described in 1896 by Antoine Marfan using the term pattes d'araignée, which means spider legs. In 1902, Emile Charles Achard proposed the term arachnodactyly for this clinical finding. The arachnoid mater had been named in 1699 by Frederik Ruysch. The clinical management of spider bites from the only two dangerous venomous spiders within the United States, the black widow spider (Latrodectus mactans) and the brown recluse spider (Loxosceles reclusa), is reviewed.

Loxosceles reclusa (L.reclusa) is known to bite humans, and its venom includes several enzymes that cause clinical symptoms. Loxoscelism, a condition due to being bitten by Loxosceles spiders, commonly known as recluses, can involve a range of clinical conditions, from local cutaneous lesions to severe systemic involvement. The diagnosis of loxoscelism is usually made by anamnesis and clinical findings. Magnetic resonance imaging is recommended for patients at high risk of necrotizing fasciitis. Treatment modalities are still controversial and there is no standardized treatment approach. Reported here, our case of loxoscelism involved a 24-year-old man presenting with a Loxosceles spider bite, dermonecrotic lesion, vomiting, diarrhea, acute renal injury, and rhabdomyolysis, who was successfully treated with hyperbaric oxygen therapy, therapeutic apheresis, hemodialysis, wound debridement, and cutaneous autografting. Early diagnosis and multidisciplinary approach can be life-saving in spider bites that can cause systemic involvement. Loxoscelism should be considered in patients with skin necrosis, acute renal injury, and rhabdomyolysis.

Introduction: Systemic loxoscelism is the most severe complication of loxoscelism. The management of the cadre by health personnel presents a high variability due to factors that are currently unknown. There is no standard of reference or a clinical prediction model that can guide our decisions when approaching a spider bite patient. Objective: Develop and validate a clinical prediction rule for systemic loxoscelism. Methods: An observational study of derivation and validation of a clinical prediction model was carried out with diagnostic test validation based on a historical single-arm cohort in patients treated at Vitarte Hospital between 2007 and 2016 and international clinical reports published. Results: Systemic loxoscelism occurred only in 32.9% (n = 24) of cases. For the bivariate analysis, the variables that showed a statistically significant association (P

Loxoscelism is a systemic inflammatory reaction in response to a brown recluse spider bite (BRSB). In this case we describe a patient with a heightened inflammatory response to a presumed BRSB, with Coomb's positive hemolysis, cytoplasmic antineutrophil cytoplasmic antibody (cANCA) vasculitis, and features of hemophagocytic lymphohistiocytosis (HLH). A 24-y-old female presented with sudden pain and swelling to her lower back, nausea, fever, and tachycardia after a presumed BRSB. Hemolysis began on hospital day 3 (15.9 g·dL-1) with a nadir on hospital day 5 (6.3 g·dL-1). She had an lactate dehydrogenase of 1415 U·L-1, ferritin of 15534 ng·mL-1, persistent fever, and signs of bone marrow suppression despite hemolysis, with thrombocytopenia (100,000 μL-1) and an inadequate reticulocyte response (1.7%) suggestive of HLH. The patient's blood was Coomb's and cANCA/antiproteinase 3 positive. She had signs of toxin-induced vasculitis, with respiratory failure requiring bilevel positive airway pressure, radiographs with bilateral pulmonary infiltrates, and a desquamating rash. She received 6 U of packed red blood cells, furosemide for pleural and pericardial effusions, antibiotics, and symptomatic treatment during the acute phase of her illness. Hemolysis improved without glucocorticoids by hospital day 6. The patient demonstrated a dysregulated immunologic and complement-mediated response to the presumed BRSB. The triad of Coomb's positive hemolysis, cANCA vasculitis, and HLH-like reaction associated with a presumed BRSB is described for the first time in the literature and brings up questions for future research regarding the role of immune modulators and complement inhibitors in the treatment of severe loxoscelism as well as the genetic factors that predispose certain individuals to such reactions.

Background/Aim: Brown recluse spider bite releases hemolytic and cytotoxic phospholipase D to the wound that may cause necrosis or even death. We examined diethyl azelate (DEA), a plasma membrane fluidizer with a broad range of immunomodulatory activities, as a potential treatment for the brown recluse spider bite. Materials and Methods: Topical DEA was used in emergency to treat brown recluse spider bites in a human subject. We subsequently evaluated the effects of DEA on hemolysis induced by the brown recluse spider venom, recluse recombinant phospholipase D (rPLD), and venoms from honey bee and moccasin snake, and on phospholipase A2 activity in the bee and snake venoms and in human urine. Results: Topical DEA resolved the consequences of human brown recluse spider envenomation in two weeks. In vitro, DEA inhibited hemolysis caused by the brown recluse spider venom and rPLD and suppressed phospholipase A2 activity in a dose-dependent manner. Conclusion: DEA is a promising novel therapy for the brown recluse spider bite and perhaps even unrelated envenomations involving PLDs.

Brown recluse spiders, also known as Loxosceles reclusa, are endemic to the Southwest and Central Midwestern United States. A bite from this spider can cause a range of clinical manifestations, anywhere from a painless papular lesion to life-threatening reactions. We report a possible spider bite presenting as leukostasis initially suspected to be acute leukemia. A 22-year-old female patient presented to the emergency department with confusion and right upper arm pain, redness, and swelling after a suspected spider bite. Initial labs showed WBC count of 103.5x10e3/µL, hemoglobin of 3.3 g/dL, positive Direct Coombs’ test, creatinine of 1.8 mg/dL, transaminitis, and lactic acid of 20 mmol/L. Acute leukemia with leukostasis was suspected. She was started emergently on hydroxyurea in conjunction with prophylaxis for tumor lysis syndrome. However, peripheral smear showed left-shifted granulocytosis with lymphocytosis, monocytosis, and no blast cells or evidence of myelodysplasia. Bone marrow aspirate showed mildly hypercellular marrow with myeloid hyperplasia and no myelodysplasia. Flow cytometry analysis confirmed a left-shifted myeloid maturation pattern with 0.3% myeloblasts. BCR-ABL1 and JAK2 testing was negative. Hence, she had no evidence of leukemia but rather had leukostasis from a spider bite. Hydroxyurea was stopped and follow-up labs normalized. Sphingomyelinase D in the brown recluse spider venom is unique to Loxosceles and Sicarius and may be responsible for the unique clinical presentation of loxoscelism. The presentation of hyperleukocytosis complicated by shock with an unclear history poses a diagnostic challenge. In diagnostic uncertainty, consider delaying chemotherapy until a diagnosis can be confirmed to avoid potential harm.

Brown recluse spider is a spider of the genus Loxosceles and also known as violin spider or fiddle-back spider. Brown recluse spider is characterized by having six eyes, with a pair in front, a pair on both sides, and a gap between the pairs. The other spiders have eight eyes in two rows of four. Brown recluse spider bites are challenging to verify but may be clinically diagnosed with consideration of geographic location, seasonality, and clinical characteristics. We present a case that involves a brown recluse spider bite in a 59-year-old female with malnutrition and polysubstance use who developed systemic symptoms and a dermonecrotic wound. Local wound care and intravenous (IV) antibiotics lead to clinical improvement by hospital day three, at which time the patient left against medical advice. The case highlights the challenges of diagnosing a brown recluse spider bites, particularly in a patient with multiple risk factors for necrotizing soft tissue infection. Furthermore, the present case represents one of the few case reports of a brown recluse spider bite in Michigan.

Patient: Male, 16-year-old Final Diagnosis: Toxic myocarditis Symptoms: Cardiogenic shock • disseminated intravascular coagulation • heart failure Medication: — Clinical Procedure: Immunoglobulin therapy • plasmapharesis Specialty: Critical Care Medicine • Toxicology Objective: Rare coexistence of disease or pathology Background: Envenomation from the brown recluse spider (Loxosceles reclusa) is described to cause both local and systemic symptoms. We report a case of an adolescent boy who developed severe systemic loxoscelism, and his clinical course was complicated by myocarditis, which has not been previously reported in association with loxoscelism. Case Report: A 16-year-old boy presented with non-specific symptoms and forearm pain following a suspected spider bite, which subsequently evolved into a necrotic skin lesion. During his clinical course, he developed a characteristic syndrome of systemic loxoscelism with hemolysis, disseminated intravascular coagulopathy, and severe systemic inflammatory response syndrome, necessitating transfer to the Intensive Care Unit. The diagnosis was confirmed with an enzyme-linked immunosorbent assay that detected Loxosceles venom in the wound. Additionally, he developed pulmonary edema and cardiogenic shock secondary to myocarditis, which was confirmed with cardiac magnetic resonance imaging. Steroids and plasmapheresis were initiated to manage the severe inflammatory syndrome, and the myocarditis was treated with intravenous immunoglobulins, resulting in resolution of symptoms and improvement of cardiac function. Conclusions: This is the first reported case of myocarditis associated with loxoscelism, providing evidence for Loxosceles toxin-associated cardiac injury, which has been previously described in animal models only. Furthermore, this case provides further support for the use of confirmatory testing in the clinical diagnosis of loxoscelism.

not present

Background Loxoscelism is an important public health problem in Chile and South America, due to the higher rate of cutaneous-visceral involvement. The diagnosis of loxoscelism is mostly clinical without established diagnostic criteria. There is little evidence to support any treatment used in this condition. Aim To characterize the clinical features and epidemiology of loxoscelism among patients consulting at the Emergency and Dermatology Services of a clinical hospital between 2013 and 2017. Material and methods Review of medical records of patients registered in the electronic clinical record system with a confirmed diagnosis of loxoscelism. Epidemiological, clinical, laboratory tests and treatment variables were analyzed. Results We reviewed data from 200 patients. Ninety-four percent presented cutaneous loxoscelism and 5.5% cutaneous-visceral loxoscelism. Systemic symptoms were present in 73% of patients with cutaneous-visceral loxoscelism. Patients who developed systemic symptoms had an 18 times higher risk of developing cutaneous-visceral loxoscelism. Laboratory abnormalities were more common in patients with cutaneous-visceral loxoscelism. Not all patients with hematuria had cutaneous-visceral loxoscelism. Most patients required analgesia. Anti-loxosceles serum was not used in any patient. Conclusions Many questions remain to be answered regarding the diagnosis and treatment of the disease. Studies are required to validate diagnostic criteria for loxoscelism, predictors for visceral involvement and response to treatment.

Spiders are eight-legged arthropods that belong tothe arachnids class and are found on every continentexcept Antarctica.1 As of 2020, there are over 48000recognized species of spiders with more than 5000in the Mediterranean area. Out of these, only twospiders, the Latrodectus tredecimguttatus and theLoxosceles rufescens are of medical significance in theMediterranean area.1 Although most spider bites arebenign; however, severe reactions and life-threateningenvenomation do occur.

The taxonomic status of the medically important spider genus Loxosceles Heineken et Lowe, 1832 (Sicariidae) in Iran, Turkmenistan, and Afghanistan is revised. Two species are described as new to science: Loxosceles coheni sp. n. (♂♀, southwestern Iran) and Loxosceles turanensis sp. n. (♂♀, southern Turkmenistan and eastern Iran). Additionally, Loxosceles alicea Gertsch, 1967 syn. n. (♀, Peru) is synonymized with Loxosceles rufescens (Dufour, 1820). The local distribution of all treated species is mapped (including several new records), and reported cases of loxoscelism from this region are briefly reviewed.

A previously healthy 27 year-old male presented to an emergency department (ED) in central Virginia two hours after a LR envenomation to his left proximal arm. He was treated with diphenhydramine and discharged on oral methylprednisolone for a 5-day taper. On post-bite Days 1 and 2, the patient developed subjective fevers, chills, arthralgias, and myalgias, followed by a blanching, pruritic, morbilliform rash throughout his trunk and lower extremities. Post-bite Day 3, the patient presented to the ED again because of marked erythema of face and the right lateral thigh, and posterior and anterior trunk. Vital signs and laboratory analysis were generally unremarkable. The patient was observed overnight, and discharged with a prescription for prednisone 60 mg per day. On post-bite Day 7, the patient noted a petechial rash on the palms and soles and returned to the ED with a fever of 102.6 °F, a heart rate of 130 beats per minutes, and systolic blood pressure ranging 80-90 mmHg. After considering this may be an atypical presentation of LX, corticosteroids were increased to methylprednisolone 1 mg/kg IV every 6 h. The patient's condition slowly improved and he was discharged on post-bite Day 10. On post-bite Day 24, he had nearly complete resolution of skin findings.LR envenomation can cause a variety of dermatological and systemic manifestations of toxicity. It is critical for toxicologists to be aware of the variety of presentations and findings to appropriately assess and treat LX.

The Hemiscorpius lepturus scorpion and brown spider Loxosceles intermedia represent a public health problem in Asia and America, respectively. Although distinct, these organisms contain similar toxins responsible for the principal clinical signs of envenomation. To better understand the properties of these toxins, we designed a study to compare recombinant Heminecrolysin (rHNC) and rLiD1, the major phospholipase D toxins of scorpion and spider venom, respectively. Using a competitive ELISA and a hemolytic inhibition test, we come to spot a cross reaction between scorpion and spider venoms along with an epitopic similarity between rHNC and rLiD1 associated with neutralizing antibodies. Results show that the ability of the rHNC to hydrolyze lysophosphatidylcholine (LPC) is equivalent to that of rLiD1 to hydrolyze sphingomyelin and vice-versa. rHNC exclusively catalyze transphosphatidylation of LPC producing cyclic phosphatidic acid (cPA). The in-silico analysis of hydrogen bonds between LPC and toxins provides a possible explanation for the higher transphosphatidylase activity of rHNC. Interestingly, for the first time, we reveal that lysophosphatidic acid (LPA) can be a substrate for both enzymes using cellular and enzymatic assays. The finding of the usage of LPA as a substrate as well as the formation of cPA as an end product could shed more light on the molecular basis of Hemiscorpius lepturus envenomation as well as on loxoscelism.

BACKGROUND: The spiders of the Loxosceles genus, commonly denoted as “brown spiders” or “Mediterranean recluse” or “brown recluse,” belong to the spider family Sicariidae, suborder Labidognatha, order Araneida, class Arachnida, and phylum Arthropoda. This spider is widespread in Africa and South/Central America, but it is also distributed in North America, in the West Indies, in the Mediterranean Europe, and in China. CASE REPORT: Here, we report the case of a severe dermonecrotic loxoscelism identified in Southern Italy, probably due to the bite of Loxosceles rufescens. The patient was a women admitted at hospital ER because of a little skin erythema that evolved toward a severe necrosis and ulceration within 20 days. After clinical and laboratory data excluded other local and systemic diseases, she was treated with a systemic and local therapy using corticosteroids and antibiotics with the diagnosis of loxoscelism. The healing from the local skin lesion occurred within 2 months, but the local pain, weakness, and discomfort lasted for a long time. CONCLUSION: It is the fisrt time that a possible case of systemic loxoscelism with skin generalized urticaria is reported in Italy.

Spider bites are a common emergency department complaint, accounting for ~21% of noncanine bites, injuries, and stings. Military service members, more so than most civilian personnel, are exposed to conditions that place them at increased risk for envenomation, stings, and bites. We present the case of an active duty service member working in a relatively austere environment who presented to a level 1 trauma center with a lesion consistent with a bite from a brown recluse spider, or Loxosceles reclusa.

Pathogenic biofilms are considered a potential major obstacle to healing chronic wounds. The six-month evaluation period in this study assessed the effect of a single treatment of the HYBENX® (HYB) Root Canal Cleanser on chronic wounds, especially its ease of use, safety, potential for shortening duration of Inflammatory Phase, and promotion of granulation. HYB gel was applied to the wound bed and periwound skin for 10 seconds. Gel was removed by cotton gauze pads and low-pressure saline rinsing. Standard wound dressings based on wound etiology, location, and exudate characteristics were applied. Duration of these seven HYB-treated wound cases (two pressure ulcers, one surgical wound, four lower extremity ulcers-a venous reflux-associated calf ulcer, one diabetic foot ulcer, and two animal-induced wounds-brown recluse spider and bovine bite) ranged from 12 days to 10 years. Three cases had sinus tracts. After HYB application, sinus tract closure occurred at 7, 16, and 21 days. The 10-year recalcitrant wound from brown recluse spider bite healed in 97 days. Diabetic foot ulcer responded to HYB treatment plus additional strategies and healed in six months. These data support the hypotheses that pathogenic biofilm actively prevents the healing of chronic wounds, and biofilm can be disrupted with a single HYB treatment.

Though there are over 40,000 species of spiders and 2,000 species of scorpions worldwide, many spiders are incapable of biting humans and very few spiders and scorpions produce clinically significant bites or stings. Most spider bites and scorpion stings in humans cause minimal or no effects and rarely result in more than a local cutaneous reaction. The two spiders in the United States that are associated with potentially serious health consequences are the brown recluse (Loxosceles reclusa) and the black widow (Latrodectus mactans) spiders. Bites from the brown recluse spider can produce necrotic ulceration, while black widow spider bites can cause severe systemic features. The two scorpions in the United States causing medical relevant symptomatology are the Arizona bark scorpion (Centruroides exilcauda or sculpturatus) and striped bark scorpion (Centruroides vittatus). The Arizona bark scorpion is known to cause systemic neurotoxic symptoms and may be life-threatening, while the striped bark scorpion causes only local pain. Maintaining a broad differential diagnosis when considering a spider bite is essential due to the lack of confirmatory diagnostic testing. Scorpion stings are typically evident and also lack diagnostic testing. The treatment of spider bites and scorpion stings should include local wound care, pain management, and monitoring of systemic toxicity with a low threshold for antivenom administration. Spider bites can be prevented with the use of appropriate clothing and chemical repellents, such as N,N-diethyl-3-methylbenzamide (DEET), as well as other personal and domestic measures. Scorpion stings may be prevented through wearing appropriate protective clothing. Morbidity and mortality can be decreased through public awareness of endemic scorpion behavior and education as to when to seek medical care.

We conducted a two-year mark-recapture study of a synanthropic population of the brown recluse spider Loxosceles reclusa Gertsch & Mulaik, 1940 in northwestern Illinois. We used joint live encounter and dead recovery models to estimate adult survival, recapture, and dead recovery probabilities. To estimate adult abundance, we used full-likelihood closed-population models. Monthly survival was constant between sexes (0.73, 95% CI = 0.66–0.78), but males were less likely to be recaptured and an additive effect of time revealed highest recapture probabilities in September. The probability of recovering a marked adult that died during the study was 0.13 (95% CI = 0.07–0.24). Average life expectancy for adults was 94 days, much lower than in prior laboratory studies. Causes of observed mortality were predation by conspecifics and cobweb spiders (Parasteatoda tepidariorum (C.L. Koch, 1841)) or undetermined. A likely source of mortality for this sit-and-wait predator is starvation. Model averaging of full likelihood closed-population models resulted in adult abundance estimates that were similar between males (28, 95% CI = 20–63) and females (28, 95% CI = 26–38). However, the total population of adults including those hidden in harborage (boxes, furniture, crevices etc.) was undoubtedly much higher. Based on count data, immature spiders were as abundant as adults early in the year, gradually increasing to a peak three times greater by mid-summer. Male spiders moved longer distances than females and were less likely to exhibit site fidelity. The average tenure of a female at a specific site was nearly 8 days.

During the winter of 2014–15 in southern California, attempts were made to accelerate immature brown recluse spiders, Loxosceles reclusa Gertsch & Mulaik, 1940, to maturity for a pest control experiment in early spring. Despite food offerings, spiders stopped molting after October although they were maintained at 25° C and had swollen, well-nourished abdomens. It was surmised that decreased filtered daylight from a paper-covered window might be suppressing molting. Feeding was halted in January 2015; 88 spiderlings were checked weekly for molts. Molting resumed during late March 2015 and continued through May 2015 despite no feedings. To more thoroughly elucidate photoperiod effects on molting, during the week of the September 2015 equinox, three cohorts of 10 immatures of both brown and Chilean recluses, L. laeta (Nicolet, 1849), were exposed to three light regimes: 14:10 L:D, natural, 10:14 L:D. Through November 2015 to late March 2016 for brown recluses, there was no molting in the 10:14 regime, 3 of 10 spiders molted in the natural light regime, and 8 of 10 spiders molted in the 14:10 L:D regime. Additionally, fifteen newly-emerged brown recluse spiderlings split into three cohorts of 5 spiders each in November exhibited more molting in the 14:10 L:D compared to natural and 10:14 L:D light cycles. Chilean recluses showed no differences in molting across the three photoperiod regimes. This species difference may be explained in that brown recluses are native to temperate zones where winters can be fatal; Chilean recluses are tropical where short photoperiods may have little significance for survival.

Acute cutaneous necrosis is characterised by a wide range of aetiologies and is associated with significant morbidity and mortality, warranting complex considerations in management. Early recognition is imperative in diagnosis and management of sudden gangrenous changes in the skin. This review discusses major causes of cutaneous necrosis, examines the need for early assessment, and integrates techniques related to diagnosis and management. The literature, available via PubMed, on acute cutaneous necrotic syndromes was reviewed to summarise causes and synthesise appropriate treatment strategies to create a clinician’s guide in the early diagnosis and management of acute cutaneous necrosis. Highlighted in this article are key features associated with common causes of acute cutaneous necrosis: warfarin-induced skin necrosis, heparin-induced skin necrosis, calciphylaxis, pyoderma gangrenosum, embolic phenomena, purpura fulminans, brown recluse spider bite, necrotising fasciitis, ecthyma gangrenosum, antiphospholipid syndrome, hypergammaglobulinemia, and cryoglobulinemia. This review serves to increase recognition of these serious pathologies and complications, allowing for prompt diagnosis and swift limb- or life-saving management.

Bites by Loxosceles spiders (also known as recluse spiders or brown spiders) can cause necrotic ulcerations of various sizes and dimensions. The current standard of care for brown spider bites includes analgesics, ice, compression, elevation, antihistamines, and surgical debridement. Hyperbaric oxygen therapy (HBOT) in the treatment of brown spider bites has been administered in the early stage of ulceration, or 2 to 6 days after the bite. Unfortunately, the diagnosis of spider bite-related ulcers is often delayed and weeks or months may elapse before HBOT is considered.To evaluate the effect of HBOT on nonhealing wounds caused by brown spider bites in the late, chronic, nonhealing stage.Analysis of 3 patients with brown spider-bite healing wounds treated at The Sagol Center for Hyperbaric Medicine and Research in Israel. Patients presented 2 to 3 months after failure of other therapies including topical dressings, antibiotics, and corticosteroids. All patients were treated with daily 2 ATA (atmospheres absolute) with 100% oxygen HBOT sessions.All 3 patients were previously healthy without any chronic disease. Their ages were 30, 42, and 73 years. They were treated once daily for 13, 17, and 31 sessions, respectively. The wounds of all 3 patients healed, and there was no need for additional surgical intervention. There were no significant adverse events in any of the patients.Microvascular injury related to brown spider bites may culminate in ischemic nonhealing wounds even in a relatively young, healthy population. Hyperbaric oxygen therapy should be considered as a valuable therapeutic tool even months after the bite.

We present the first record for Loxosceles gaucho Gertsch, 1967 in the Amazonian region of Brazil. Four males, fifteen females and forty-nine immatures were collected in different places in Manaus, Amazonas, Brazil. This is the third species of Loxosceles reported in the Amazon region along with L. amazonica Gertsch, 1967, and L. similis Moenkhaus, 1898. This is the first record of an invasive species of a venomous animal in the state of Amazonas, Brazil, which is noteworthy due to its synanthropic habit, which increases the risk to the local population. © 2019, Universidade de Sao Paulo. All rights reserved.

The brown recluse, or fiddleback (violin) spider, is a poisonous spider of the Loxosceles genus that resides in warmer regions and old structures making the warm Mediterranean climate a natural habitat for the European species, L. rufescens. Even in infested households, however, bites are rare, as they are nocturnal and unaggressive. In 2015, the first supposed death by L. rufescens occurred in Italy, but before and even after such bite, the literature on these spiders has been under-represented. This case report documents a confirmed bite by a violin spider on a medical student in Pavia, Italy. The presentation in this case was initially with general systemic, flu-like symptoms, then as cellulitis with lymphangitis that persisted for nearly 2 weeks until resolving without prolonged or complicated pathology. We present the first documented case of a L. rufescens bite in Northern Italy, to the best of our knowledge.

Brown spider phospholipases D from Loxosceles venoms are among the most widely studied toxins since they induce dermonecrosis, triggering inflammatory responses, increase vascular permeability, cause hemolysis, and renal failure. The catalytic (H12 and H47) and metal-ion binding (E32 and D34) residues in Loxosceles intermedia phospholipase D (LiRecDT1) were mutated to understand their roles in the observed activities. All mutants were identified using whole venom serum antibodies and a specific antibody to wild-type LiRecDT1, they were also analyzed by circular dichroism (CD) and differential scanning calorimetry (DSC). The phospholipase D activities of H12A, H47A, H12A-H47A, E32, D34 and E32A-D34A, such as vascular permeability, dermonecrosis, and hemolytic effects were inhibited. The mutant Y228A was equally detrimental to biochemical and biological effects of phospholipase D, suggesting an essential role of this residue in substrate recognition and binding. On the other hand, the mutant C53A-C201A reduced the enzyme's ability to hydrolyze phospholipids and promote dermonecrosis, hemolytic, and vascular effects. These results provide the basis understanding the importance of specific residues in the observed activities and contribute to the design of synthetic and specific inhibitors for Brown spider venom phospholipases D.

We present the case of a healthy patient who sustained a spiderbite in the elbow and developed a non-infectious necrotizing fasciitis in the affected limb. Female patient aged 24 pain reported a spiderbite received some 72 h previously in Mexico (the spider was identified as a brown recluse spider-Loxosceles reclusa). Under the suspected diagnosis of necrotizing fasciitis urgent surgery was indicated. During her hospital stay, the patient required three additional surgical procedures, and was discharged from hospital 30 days after admission. Spider bites in the limb may be limb-threatening and life-threatening. Emergency doctors should be aware of this possibility, because spiders can be unintentionally transported all over the world.

Accidents with venomous animals pose a health issue in Brazil, and those involving brown spiders (Loxosceles sp.) figure between the most frequent ones. The accidental envenomation by brown spiders causes a strong local dermonecrotic effect, which can be followed by systemic manifestations that in some cases lead to death. The production of antivenoms for the treatments of such accidents relies on a variety of animal experiments, from the spider venom extraction to the production of antivenom in horses. In the present work, there is an attempt to reduce and optimize animal experiments with the construction and production of a chimeric protein, named Lil, containing immunodominant epitopes previously mapped from the main proteins of the Loxosceles venom, the Sphingomyelinases D. The Lil protein contains epitopes from Sphinomyelinases D of the three-main species found in Brazil and this chimeric protein was found capable of inducing antibodies with the potential to partially neutralize the toxic effects of Loxosceles intermedia venom in an animal model. Therefore, in order to reduce spider usage and to improve the lifespan of the horses used for immunization we suggest the Lil protein as a potential candidate to replace the venom usage in the antivenom production protocols.

The species Loxosceles rufescens is native to the Mediterranean but considered cosmopolitan because it has been dispersed worldwide. A previous study revealed 11 evolutionary lineages across the Mediterranean, grouped into two main clades, without any clear phylogeographic pattern. The high genetic diversity within this species (p-distances of up to 7.8% in some Mediterranean lineages), together with the results obtained with different species delimitation methods (GMYC, TCS) could indicate the existence of cryptic species. Here we compare the mitochondrial and microsatellite diversity to elucidate if the lineages of L. rufescens in the Mediterranean should be considered different species (cryptic species) or populations of the same species. To do so, we analyzed the cox1 diversity of 196 individuals, of which, we genotyped 148, sampled from 19 localities across the Mediterranean. STRUCTURE analyses of microsatellite data identified two genetic clusters of L. rufescens. One cluster included individuals from Western Mediterranean localities (Iberian Peninsula, Morocco, Balearic Islands) and Israel, while the second one grouped individuals from Italian and Greek localities, including Sardinia, Sicily and Tunisia. These patterns suggest that geographic proximity is the more significant factor in the clustering with microsatellite data and shows the existence of gene flow between the nearest geographic areas, even if the individuals belong to different mitochondrial lineages or clades. The lack of correspondence between both genetic markers suggests that the evolutionary lineages found within L. rufescens should not be considered different species. We conclude that these phylogenetic linages and their distribution may be the result of the maternal evolutionary history of the species and human-mediated dispersion.

Exaggerated arthropod bite reactions causing hemorrhagic or necrotic bullous lesions can mimic other serious conditions such as cutaneous anthrax, brown recluse spider bite, and tularemia. A 55- year-old, healthy woman presented to the emergency department with a 3.5-centimeter painless, collapsed hemorrhagic bulla at the left costal margin. She was afebrile and had no systemic symptoms. Laboratory evaluation was unremarkable. She was prescribed silver sulfadiazine cream and mupirocin ointment. The area denuded two days later and the lesion completely healed. This case illustrates the broad differential to be considered when evaluating patients with hemorrhagic bullous lesions.

Brown recluse spiders are known for the necrotic skin lesions they may produce. However, there is frequent misdiagnosis of brown recluse bites due to similar dermonecrotic lesions resulting from other conditions such as impetigo, decubitus ulcers, staph infections, ecthyma gangrenosum, and the like. This chapter presents facts and fables about brown recluse spiders, their bite reactions, and various treatment and control strategies.

Loxosceles Heineken & Lowe, 1832 spiders are infamous for their medical importance, but a taxonomic picture of the genus is still far from complete. In this study, the Chilean species of Loxosceles are described and mapped. The males of Loxosceles surca Gertsch, 1967 and L. coquimbo Gertsch, 1967 are described for the first time. Three new species with narrow distributions are described from central and northern Chile: Loxosceles diaguita sp. nov. from the Antofagasta Region, L. pallalla sp. nov. from Coquimbo and L. vallenar sp. nov. from Atacama. The first two species are remarkable in their morphology and do not fit into any of Gertsch?s species groups, suggesting that Chile still harbours an undiscovered phylogenetic diversity of the genus. New distribution records for Loxosceles laeta (Nicolet, 1849) are provided throughout Chile. Fil: Brescovit, Antonio Domingos. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; Brasil Fil: Taucare-Ríos, Andrés. Universidad Arturo Prat; Chile Fil: Fiorini de Magalhaes, Ivan Luiz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina Fil: Santos, Adalberto J.. Universidade Federal de Minas Gerais; Brasil

There is a need for safe and consistent management of the brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, a toxic spider found in homes throughout Kansas and the south and central United States. This study examined the efficacy of two general-use insecticides with brown recluse on their labels, .05% bifenthrin with 0.0125% zeta-cypermethrin (Insecticide 1), and 0.03% lambda-cyhalothrin (Insecticide 2) against the brown recluse spider at three times post-treatment, 1, 24, and 96 hr, and on two substrates, carpet and tile. This study also evaluated the efficacy of these insecticides on spiders exposed for three lengths of time, 0.5, 1, and 30 min on each substrate. Results indicate that Insecticide 2 had better overall residual efficacy than Insecticide 1. In addition, in one experiment efficacy was better when the spiders were exposed on tile surfaces. Residual efficacy for Insecticide 2 was greater one and 24 hr after application but decreased at 96 hr. The efficacy of Insecticide 1 wa...