Brown recluse spider bites

BACKGROUND

Brown recluse spider bites are a serious medical problem in the southeastern United States. Although most bites are asymptomatic, envenomation can result in a constellation of systemic symptoms referred to as loxoscelism. Patients can also develop necrotic skin ulcers (necrotic arachnidism). These ulcers are often difficult to heal and can require skin grafting or amputation of the bitten appendage.

METHODS

A search of the literature was performed using the search words "spider envenomation," "brown recluse spider bites," and "arachnid envenomation."

RESULTS AND CONCLUSIONS

Most brown recluse spider bites are asymptomatic. All bites should be thoroughly cleansed and tetanus status updated as needed. Patients who develop systemic symptoms require hospitalization. Surgical excision of skin lesions is indicated only for lesions that have stabilized and are no longer enlarging. Steroids are indicated in bites that are associated with severe skin lesions, loxoscelism, and in small children. Dapsone should be used only in adult patients who experience necrotic arachnidism and who have been screened for glucose-6-phosphate dehydrogenase deficiency. Topical nitroglycerin can be of value in decreasing the enlargement of necrotic skin ulcers.

Brown recluse spider bite to the eyelid

PURPOSE

To present a photographically documented case of a known brown recluse spider bite to the eyelid.

DESIGN

Interventional case report.

METHODS

The wound was photographed daily during an 11-day hospitalization and at 1 month and 6 months after the injury. Treatment included canthotomy and cantholysis; administration of dapsone, antibiotics, and steroids; and hyperbaric oxygen therapy.

MAIN OUTCOME MEASURES

Clinical presentation and course of a known brown recluse spider bite.

RESULTS

Complete recovery with cicatrization at the site of the bite.

CONCLUSIONS

We present a case of a brown recluse spider bite to the left lower eyelid with a discussion of management and outcome of this rarely reported injury.

[Envenomations]

Although venomous animals are less frequent in Europe than in tropical countries, some dangerous species can be responsible of envenomations in France. Bites by two species of adders (Vipera aspis and Vipera berus) can lead to extensive swelling with multiorgan failure. Treatment is based on intravenous infusions of specific antivenom. Bites and stings by other animal species encountered in France are characterised by important pain with local signs like necrosis, bleeding or oedema: weevers, scorpion fish, centipedes, bees, wasps.... Contrary to scorpions of North Africa or India, the 5 scorpion species which live in France are completely harmless. Such is not the case with spiders: latrodectism (neurotoxicity) and loxoscelism (extensive necrosis) observed in Provence and in Corsica.

Bites and stings from venomous animals: a global overview

Venomous and poisonous animals are a significant cause of global morbidity and mortality. This Seminar will cover selected aspects of these animals, their venoms/poisons, and their clinical impact on humankind, from a global perspective, but with a distinctive Australian flavor and a clinical emphasis. Venomous snakes are found throughout most of the world, including many oceans, and have evolved a variety of highly effective toxins and methods of delivery. Their impact on humans is considerable, most current data suggesting they cause in excess of 3 million bites per year with more than 150,000 deaths. Particularly in the rural tropics, snakebite morbidity and mortality has a significant human medical and economic toll. The major groups of snakes causing bites are the vipers, the elapids (cobra type), the sea snakes, the side-fanged vipers, and the back-fanged colubrids. Australian venomous snakes are nearly all elapids and have evolved some of the most toxic of all snake venoms. Their effects include potent procoagulants and anticoagulants, neurotoxins, myotoxins, and nephrotoxins, but a distinct absence of the major local necrotoxins found in some non-Australian elapids and many vipers. The effect of these toxins on humans is not limited to envenoming, for the toxins are proving invaluable as research tools and diagnostic agents, and may even have a future as precursors of therapeutic agents. Because of the high toxicity and diversity of Australian elapids, a variety of monovalent antivenoms have been developed. There is also a venom detection kit to determine the type of snake and allow targeted antivenom therapy. The kit has also increased information available on diagnostic patterns of envenoming for each species. Australia is also home to the world's most lethal spiders, the funnel webs of eastern Australia, as well as the red back spider, the single most common reason for antivenom treatment in Australia. The latter spiders have been accidently exported to Japan. Within the marine environment exist a vast array of toxic animals, both poisonous and venomous, which not only cause morbidity and mortality in humans, but offer an incredibly rich array of valuable toxins. Australian waters contain some of the most lethal and medically problematic species, presenting a diverse range of clinical problems.

Green lynx spider (Peucetia viridans) envenomation

Four cases of envenomation by green lynx spiders (Peucetia viridans) are reported. Despite the unusual appearance and occasional aggressive behavior of this spider, envenomation caused only local pain, pruritus, erythema, and induration. No local necrosis or systemic symptoms occurred. Treatment included tetanus immunization, wound care, and symptomatic therapy.

Funnel-web spider (Hadronyche infensa) envenomations in coastal south-east Queensland

Five patients with confirmed funnel-web spider bites (Hadronyche infensa) presented to Nambour General Hospital, in south-east Queensland, between 1992 and 1998. Two patients required antivenom; low doses of antivenom were effective. Patients were bitten in spring and early summer. In areas such as this, where funnel-web spider bites are reported less frequently than in New South Wales, clinicians and the community should be aware of the risks and immediate management of these bites.

Brown recluse spider bites

The bite of the brown recluse spider (BRS) is the most severe arthropod cause of necrotic skin lesions. The severity of cutaneous injury due to BRS bites vary from mild erythema to severe necrosis. Rarely, severe systemic reactions occur. Diagnosis may be difficult, since the victim may not feel the bite or see the spider. Treatment must be individually tailored. Proper treatment, reassurance, and rapid followup are helpful in reducing the cutaneous and psychologic discomfort associated with BRS bites.

Antivenom therapy in the Americas

Envenomations are an important cause of injury in the Americas. While supportive care alone may result in an acceptable outcome, antivenom offers a specific therapy that can significantly reduce the injury and symptoms of the envenomation. Antivenoms are hyperimmune sera collected from animals immunised with venom. The antibodies contained in the serum bind and inactive venom components. This leads to cessation or reversal of the toxic effects of the venom. The serum is often processed to increase the level of antibodies directed against venom components and decrease the amount of inactive proteins that may cause allergic reactions. The processing may include precipitation of inactive proteins, chromatographic methods and cleavage of the immunoglobulins to form antibody fragments known as Fab or F(ab)2. In the Americas, antivenoms are produced to treat crotalid and Micrurus snake envenomations. Latrodectus and Loxosceles spider envenomations and Centruroides and Tityus scorpion envenomations. The indications, method of administration and incidence of adverse reactions differ greatly for each antivenom. The adverse effects encountered when using antivenoms are primarily allergic in nature. Anaphylaxis, which may be life threatening, is a major concern. Preparations to treat anaphylaxis must be made before initiating antivenom therapy. Serum sickness is also common with many of the antivenom preparations.

The clinical characteristics of brown recluse spider bites treated by family physicians: an OKPRN Study. Oklahoma Physicians Research Network

BACKGROUND

The brown recluse spider (Loxosceles reclusa) has been recognized as a cause of necrotizing bites since at least 1957, but most of the literature consists of laboratory studies using animals, human sera, or case reports of more dramatic examples of bite reactions. Our goal was to develop a more comprehensive clinical description of the brown recluse spider bites treated by family physicians.

METHODS

Two preprinted, postage-paid cards were given to physician members of the Oklahoma Physicians Research Network. One card was used for recording examination and treatment data, and the other was for tracking the progress of the bite until it was completely healed. For comparison, similar information was collected from the local poison control center.

RESULTS

From April 1996 to August 1998, the physicians recorded 149 bites. Most of the victims were women aged 18 to 65 years, and most sought treatment within 3 days. Pain was common but not universal. Most bites were located on the extremities. Erythema was always present, but necrosis was present in only 40% of the bites. Some systemic signs or symptoms were common. The most frequent forms of treatment were systemic antibiotics (66% of cases) and conservative wound management (56%). Only 1 hospitalization occurred; 43% of the bites healed within 2 weeks; and only 13% resulted in scarring.

CONCLUSIONS

The brown recluse spider bite is a relatively common problem treated by family physicians in Oklahoma. Most bites are not serious. More research at the practice level is needed to develop diagnostic criteria and to explore the effectiveness of various treatment options.

Envenomation by a spider, Agelenopsis aperta (family: Agelenidae) previously considered harmless

This is the first report of clinically significant bites by the grass spider (Agelenopsis aperta). Two cases of envenomation in southern California are presented. In the more serious case, a child exhibited several envenomation symptoms. Although this spider may be generally innocuous, it should be considered as a creature of occasional medical importance. Many skin lesions are attributed to spider bites despite insufficient incriminating evidence, and bites that are clinically significant may often erroneously be attributed to the brown recluse spider. Misidentification can lead to undue anxiety in a patient's family.

Envenoming and antivenom use in Australia

Australia has a diverse and rich venomous fauna, both terrestrial and marine, including some of the most venomous species in each class. Antivenom is the principal therapy for the majority of medically significant envenomings and is currently supplied through a single source, CSL, Melbourne. Cases of envenoming reported to Australian poisons information centers (PICs) are dominated by spiderbite and insect stings, respectively accounting for 53.7% and 39.3% of all bite/sting calls. Marine animal bites/stings/poisonings account for only 4% of PIC calls in this category, while snakebites account for a mere 3% (still at least 400 calls/yr). Because most PIC calls are from the public, not doctors/hospitals, snakebite in particular is under-represented. The author has recently reviewed antivenom usage in Australia. Snakebite affects between 1,000 to 3,000 people per year, with an average annual mortality of about 2 cases. Brown snakes (genus Pseudonaja) cause the majority of deaths (and bites), with tiger snakes (genus Notechis) and taipans (genus Oxyuranus) accounting for nearly all other fatalities. Up to 500 cases require snake antivenoms each year, the majority of cases coming from rural areas of Queensland, Western Australia, New South Wales and Victoria, these being the most populated states. The wide availability of snake venom detection kits has allowed specific antivenom to be used more often, rather than polyvalent antivenom, but the latter is still used in nearly 30% of cases, suggesting underutilization of venom detection. The issue of premedication prior to antivenom remains unresolved. Antivenom usage and complication data for 1995 and 1996 will be presented. Red back spider antivenom is the most commonly used antivenom, with reports of usage being greater than for all other antivenoms combined. It is reported as being therapeutically efficacious in 94% of cases, with a single ampoule being used in 76% of cases, 2 ampoules in 18% of cases, and 3 or more ampoules in 6% of cases. Clinical experience suggests only 20% of red back spider bites require antivenom therapy. It is likely that between 5-10,000 bites occur annually.