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Brown Recluse Spider Bite
Loxoscelism () is a condition occasionally produced by the bite of the recluse spiders (genus ''Loxosceles''). The area becomes dusky and a shallow open sore forms as the skin around the bite dies (necrosis). It is the only proven type of necrotic arachnidism in humans. While there is no known therapy effective for loxoscelism, there has been research on antibiotics, surgical timing, hyperbaric oxygen, potential antivenoms and vaccines. Because of the number of diseases that may mimic loxoscelism, it is frequently misdiagnosed by physicians. Loxoscelism was first described in the United States in 1879 in Tennessee. Although there are up to 13 different ''Loxosceles'' species in North America (11 native and two nonnative), ''Loxosceles reclusa'' is the species most often involved in serious envenomation. ''L. reclusa'' has a limited habitat that includes the Southeast United States. In South America, '' L. laeta'', '' L. intermedia'' (found in Brazil and Argentina), and '' L. ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Envenomation
Envenomation is the process by which venom is injected by the bite or sting of a venomous animal. Many kinds of animals, including mammals (e.g., the northern short-tailed shrew, ''Blarina brevicauda''), reptiles (e.g., the king cobra), spiders (e.g., black widows), insects (e.g., wasps), and fish (e.g., stone fish) employ venom for hunting and for self-defense. In particular, snakebite envenoming is considered a neglected tropical disease resulting in >100,000 deaths and maiming >400,000 people per year. Mechanisms Some venoms are applied externally, especially to sensitive tissues such as the eyes, but most venoms are administered by piercing the skin of the victim. Venom in the saliva of the Gila monster and some other reptiles enters prey through bites of grooved teeth. More commonly animals have specialized organs such as hollow teeth (fangs) and tubular stingers that penetrate the prey's skin, whereupon muscles attached to the attacker's venom reservoir squirt venom d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnologists
Arachnology is the scientific study of arachnids, which comprise spiders and related invertebrates such as scorpions, pseudoscorpions, and harvestmen. Those who study spiders and other arachnids are arachnologists. More narrowly, the study of spiders alone ( order Araneae) is known as araneology. The word "arachnology" derives from Greek , ''arachnē'', "spider"; and , ''-logia'', "the study of a particular subject". Arachnology as a science Arachnologists are primarily responsible for classifying arachnids and studying aspects of their biology. In the popular imagination, they are sometimes referred to as spider experts. Disciplines within arachnology include naming species and determining their evolutionary relationships to one another (taxonomy and systematics), studying how they interact with other members of their species and/or their environment (behavioural ecology), or how they are distributed in different regions and habitats (faunistics). Other arachnologists perform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brown Recluse Spider
The brown recluse (''Loxosceles reclusa''), Sicariidae (formerly placed in a family "Loxoscelidae") is a recluse spider with necrotic venom. Similar to those of other recluse spiders, their bites sometimes require medical attention. The brown recluse is one of three spiders in North America with medically significant venom, the others being the black widow and the Chilean recluse. Brown recluse spiders are usually between , but may grow larger. While typically light to medium brown, they range in color from whitish to dark brown or blackish gray. The cephalothorax and abdomen are not necessarily the same color. These spiders usually have markings on the dorsal side of their cephalothorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider, resulting in the nicknames fiddleback spider, brown fiddler, or violin spider. Description The violin pattern is not a definitive identifier, as other spiders can have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sicarius (genus)
''Sicarius'' is a genus of recluse spiders that is potentially medically significant to humans. It is one of three genera in its family, all venomous spiders known for a bite that can induce loxoscelism. They live in deserts and arid regions of the Southern Hemisphere, and females use a mixture of sand and silk when producing egg sacs. The name is Latin for assassin. Description ''Sicarius'' spiders can grow up to long, and have six eyes arranged into three groups of two (known as "dyads"). Physically, they resemble crab spiders and members of the '' Homalonychus'' genus. They lack the characteristic violin-shaped marking of the more well-known members of its family, Sicariidae the recluse spiders. They can live for a very long time without food or water. Some can live for up to fifteen years, making them among the longest-lived spiders, behind the trap-door spiders and tarantulas, many known to live for twenty to thirty years. The oldest recorded spider is Number 16, a tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphingomyelin Phosphodiesterase
Sphingomyelin phosphodiesterase (EC 3.1.4.12, also known as neutral sphingomyelinase, sphingomyelinase, or SMase; systematic name sphingomyelin cholinephosphohydrolase) is a hydrolase enzyme that is involved in sphingolipid metabolism reactions. SMase is a member of the DNase I superfamily of enzymes and is responsible for breaking sphingomyelin (SM) down into phosphocholine and ceramide. The activation of SMase has been suggested as a major route for the production of ceramide in response to cellular stresses. Sphingomyelinase family Five types of SMase have been identified. These are classified according to their cation dependence and pH optima of action and are: * Lysosomal acid SMase * Secreted zinc-dependent acid SMase * Magnesium-dependent neutral SMase * Magnesium-independent neutral SMase * Alkaline SMase Of these, the lysosomal acidic SMase and the magnesium-dependent neutral SMase are considered major candidates for the production of ceramide in the cellular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhabdomyolysis
Rhabdomyolysis (also called rhabdo) is a condition in which damaged skeletal muscle breaks down rapidly. Symptoms may include muscle pains, weakness, vomiting, and confusion. There may be tea-colored urine or an irregular heartbeat. Some of the muscle breakdown products, such as the protein myoglobin, are harmful to the kidneys and can cause acute kidney injury. The muscle damage is mostly caused by a crush injury, strenuous exercise, medications, or a substance use disorder. Other causes include infections, electrical injury, heat stroke, prolonged immobilization, lack of blood flow to a limb, or snake bites. Statins (prescription drugs to lower cholesterol) are considered a small risk. Some people have inherited muscle conditions that increase the risk of rhabdomyolysis. The diagnosis is supported by a urine test strip which is positive for "blood" but the urine contains no red blood cells when examined with a microscope. Blood tests show a creatine kinase activity greate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myonecrosis
Gas gangrene (also known as clostridial myonecrosis and myonecrosis) is a bacterial infection that produces tissue gas in gangrene. This deadly form of gangrene usually is caused by ''Clostridium perfringens'' bacteria. About 1,000 cases of gas gangrene are reported yearly in the United States. Myonecrosis is a condition of necrotic damage, specific to muscle tissue. It is often seen in infections with ''C. perfringens'' or any of myriad soil-borne anaerobic bacteria. Bacteria cause myonecrosis by specific exotoxins. These microorganisms are opportunistic and, in general, enter the body through significant skin breakage. Gangrenous infection by soil-borne bacteria was common in the combat injuries of soldiers well into the 20th century, because of non-sterile field surgery and the basic nature of care for severe projectile wounds. Other causes of myonecrosis include envenomation by snakes of the genus ''Bothrops'' (family Viperidae), ischemic necrosis, caused by vascular blockage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Kidney Failure
Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both. Causes of AKI are classified as either prerenal (due to decreased blood flow to the kidney), intrinsic renal (due to damage to the kidney itself), or postrenal (due to blockage of urine flow). Prerenal causes of AKI include sepsis, dehydration, excessive blood loss, cardiogenic shock, heart failure, cirrhosis, and certain medications like ACE inhibitors or NSAIDs. Intrinsic renal causes of AKI include glomerulonephritis, lupus nephritis, acute tubular necrosis, certain antibiotics, and chemotherapeutic agents. Postrenal causes of AKI include kidney stones, bladder cancer, neurogenic bladder, enlargement of the prostate, narrowing of the urethra, and certain medications like anticholinergics. The diagnosis of AKI is made based on a person's signs and symp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients. A normal human platelet count ranges from 150,000 to 450,000 platelets/microliter (μl) of blood. Values outside this range do not necessarily indicate disease. One common definition of thrombocytopenia requiring emergency treatment is a platelet count below 50,000/μl. Thrombocytopenia can be contrasted with the conditions associated with an abnormally ''high'' level of platelets in the blood - thrombocythemia (when the cause is unknown), and thrombocytosis (when the cause is known). Signs and symptoms Thrombocytopenia usually has no symptoms and is picked up on a routine complete blood count. Some individuals with thrombocytopenia may experience external bleeding, such as nosebleeds or bleeding gums. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disseminated Intravascular Coagulation
Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems moving parts of the body. As clotting factors and platelets are used up, bleeding may occur. This may include blood in the urine, blood in the stool, or bleeding into the skin. Complications may include organ failure. Relatively common causes include sepsis, surgery, major trauma, cancer, and complications of pregnancy. Less common causes include snake bites, frostbite, and burns. There are two main types: acute (rapid onset) and chronic (slow onset). Diagnosis is typically based on blood tests. Findings may include low platelets, low fibrinogen, high INR, or high D-dimer. Treatment is mainly directed towards the underlying condition. Other measures may include giving platelets, cryoprecipitate, or fresh frozen plasma. Evidence to support these trea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolytic Anemia
Hemolytic anemia or haemolytic anaemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically (prosthetic valve damage). Hemolytic anemia accounts for 5% of all existing anemias. It has numerous possible consequences, ranging from general symptoms to life-threatening systemic effects. The general classification of hemolytic anemia is either intrinsic or extrinsic. Treatment depends on the type and cause of the hemolytic anemia. Symptoms of hemolytic anemia are similar to other forms of anemia ( fatigue and shortness of breath), but in addition, the breakdown of red cells leads to jaundice and increases the risk of particular long-term complications, such as gallstones and pulmonary hypertension. Signs and symptoms Symptoms of hemolytic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
