Brown spider is the name given to different species of spider belonging to the genus Loxosceles. These are small spiders, with a brown body and possess a powerful venom, mainly known for its necrotic effects. Brown spider envenomation is called loxoscelism.
Loxoscelism can manifest itself in two ways: cutaneous and cutaneous-visceral. The latter is a serious form of poisoning, which can even lead to death. In general, treatment includes cleaning the bite site, administering painkillers and using cold compresses. Depending on the severity of the case, it is recommended to use serum antiloxoscelic and even blood transfusion.
Read too: anaconda — snakenot poisonous that kills its prey by constriction
Abstract about brown spider
The brown spider belongs to the genus Loxosceles.
It is a small spider that has a brown body and six eyes.
They are not aggressive spiders and are more active at night.
The brown spider's venom can cause Phe necrotizing.
Envenomation by brown spider is called loxoscelism, which can be manifested cutaneously or cutaneous-visceral.
The cutaneous form stands out as the least severe.
The cutaneous-visceral form can lead the patient to death.
Characteristics of the brown spider
brown spiders are spiders belonging to the genus Loxosceles. These are spiders found all over the world and that are very relevant to public health. All over the world, they are known 134 species of brown spiders, 18 of which were observed in the Brazil.
these spiders are relatively small, and can measure about 1 to 3 centimeters in length. A curious fact is that, unlike other spiders, they have only six eyes, which are arranged in three pairs.
They have a brown body, and it is possible to observe variations in their tones, ranging from lighter to darker colors. In the region of the cephalothorax, it is possible to observe the drawing of one violin, which may not be noticeable depending on the hue of the spider.
Brown spiders have a great ability to colonize urban areas, which is why accidents occur with some frequency. They are animalsmore active at night and are attracted to dark and dry regions. They can be found, for example, in holes of trees, under rocks, in crevices of ravines and even in cracks in walls and behind paintings and furniture. Their webs do not form regular patterns, resembling cotton threads.
See too: Brazilian wandering spider — another venomous spider species
Are brown spider bites poisonous?
Brown spiders are known as one of the most dangerous spiders in the world, being responsible for serious accidents in humans and other animals. Despite this, they are considered spiders. little aggressive, the bite being generally related to moments when the spider is pressed against the victim's body. This can occur, for example, when a person puts on a closed shoe where the spider is or lying on top of it.
The brown spider's venom is potent and can cause necrosis.. The main necrotizing component of this venom is the so-called sphingomyelinase-D. In addition to being related to the necrotic lesion, sphingomyelinase-D favors the formation of thrombi that can cause problems in blood supply.
The brown spider bite, in general, causes little pain, and therefore, the patient rarely seeks medical help in the first hours after the accident. Brown spider envenomation is called loxoscelism and can manifest itself in two ways:
cutaneous loxoscelism
Cutaneous loxoscelism stands out as the most common form of brown spider envenomation. This manifestation is also less serious. Spider venom can cause, after about six to eight hours of the bite, symptoms such as swelling, burning, itching and redness. Over time, blisters may appear on site. Subsequently, necrosis appears in the central region of the wound, which disappears and gives rise to an ulcerated lesion, which is characterized by having difficult healing. infections Secondary complications may occur as a complication of this condition.
Cutaneous-visceral loxoscelism
Cutaneous-visceral loxoscelism is a more serious manifestation, and may even lead the patient to death. Among the problems that can occur in this form of poisoning are the anemia, jaundice, renal failure, coagulation intravascular, nausea, dizziness and death. fevers, seizures, muscle pain, sensory changes, and shock may also occur in patients with cutaneous-visceral loxoscelism.
Treatment of brown spider accidents
The treatment of brown spider bites is based on patient support, with indication of analgesia, use of cold compress on the bite site, cleaning the site and rest. Hydration is also important to prevent kidney damage.
It can also be administered antiloxoscelic serum, which is used only in severe cases and moderates. It is worth mentioning that in case of secondary infections, it is necessary to use antibiotics, and in case of anemia, performing blood transfusion must be considered.
By Vanessa Sardinha dos Santos
Biology teacher
