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Are most spiders poisonous? The majority of the 3,000 spiders in the United States aren’t poisonous. Even if most spiders did bite, their fangs are too small or weak to puncture human skin. Their bites may leave itchy, red wounds that heal within a week or so. The spiders that do manage to bite through our skin and insert toxic venom can cause serious health complications. Read on to learn what spider bites look like, what spider varieties leave certain bites, and how to treat spider bites. What do spider bites look like? Identifying a spider bite is easier if you saw the spider that bit you, but it’s possible that you won’t notice the wound until hours later. Look for things like: swelling a red welt skin damage any troubling symptoms that accompany the bite Other possible symptoms that may accompany a spider bite include: itching or rash pain around the area of the bite muscle pain or cramping blister that’s red or purple in color sweating difficulty breathing headache nausea and vomiting fever chills anxiety or restlessness rashes swollen lymph glands high blood pressure Spider bites often take longer to heal than other insect bites, and they may affect skin tissues. It’s important to keep the bite clean to reduce the risk of infection. How to treat a spider bite at home In some cases, you can treat spider bites at home. For nonvenomous spider bites, follow these steps: Apply an ice pack on and off the bite for 10 minutes at a time. Elevate the area to reduce swelling. Take an antihistamine, such as diphenhydramine (Benadryl), to help with itching. Clean the area with soap and water to prevent infection. Apply antibiotic ointment to the area if blisters develop. Seek medical attention if you’re showing symptoms of a spider bite or if the symptoms don’t go away over time. Always seek medical attention if you suspect you’ve been bitten by one of the following species: brown recluse black widow hobo spider tarantula Brazilian wandering spider
The hepatitis E virus, responsible for major epidemics of viral hepatitis in subtropical and tropical countries, was cloned only 7 years ago.1 Hepatitis E was found to belong to the family of Caliciviridae, which includes the Norwalk virus—a common cause of gastroenteritis in humans—and consists of a single, plus-strand RNA genome of approximately 7.2 kb without an envelope (Fig. 1). The virus contains at least three open reading frames encoding viral proteins against which antibodies are made on exposure. These antibodies, especially those against the capsid protein derived from the second open reading frame2 and a protein of unknown function derived from the third open reading frame, are detected by currently available serologic assays. Retrospective studies on stored sera of past epidemics of viral hepatitis in Mexico, Africa, Afghanistan, Pakistan, India, Bangladesh, Burma, Nepal, and Borneo have revealed that all were caused by strains of hepatitis E. In addition, hepatitis E was found to be responsible for the hepatitis epidemic in the southern part of Xinjiang, China, in which 120,000 persons became infected between September 1986 and April 1988.3 Hepatitis E predominantly affects young adults (15 to 40 years old). The symptoms of hepatitis E are similar to those of hepatitis A. Frequently, a prodrome consisting of anorexia, nausea, low-grade fever, and right upper abdominal pain is present 3 to 7 days before jaundice develops. Aminotransferase levels peak (usually between 1,000 and 2,000 U/L) near the onset of symptoms; bilirubin levels (10 to 20 mg/dL) peak later. Jaundice usually resolves after 1 to 2 weeks. In about 10% of cases, the disease is fulminant—especially in pregnant women, among whom mortality rates as high as 20% due to hemorrhagic and thrombotic complications have been reported. No evidence has suggested that hepatitis E can cause chronic infection. Transmission is by the fecal-oral route, predominantly through fecally contaminated drinking water supplies. In addition, however, preliminary reports have suggested transmission of the hepatitis E virus through blood transfusions. Volunteer studies confirmed the presence of the virus in serum and feces before and during clinical disease.4 The virus is shed into feces approximately 1 week before symptoms develop. The incubation period varies from 2 to 9 weeks (mean duration, approximately 45 days). Until now, a few reports had described symptomatic hepatitis E acquired in Europe;5, 6 all patients with symptomatic hepatitis E in the United States were travelers returning from Mexico, Africa, or the Far East, in whom hepatitis E developed after their return home.7 In this issue of the Mayo Clinic Proceedings (pages 1133 to 1136), Kwo and associates describe a case of hepatitis E in a man who had not left the United States during the previous 10 years. Specific serologic tests for hepatitis E virus IgG (enzyme immunoassays and a fluorescent antibody blocking assay) and IgM8 (US strain-specific enzyme-linked immunosorbent assay with use of synthetic polypeptides deduced from the viral genome, as shown in Figure 1), developed at Abbott Laboratories (IgG and IgM) as well as at the Centers for Disease Control and Prevention (IgG), were used to prove that the patient indeed had acute hepatitis E. Researchers at Abbott Laboratories have prepared a report that describes most of the viral genome in this patient (Fig. I).8 Their results are interesting because this strain from the United States differs considerably from hepatitis E strains isolated in Mexico, Burma, Pakistan, or China. Furthermore, the sequence of the US strain is highly homologous (98% and 94% homology at the amino acid level to the second and third open reading frames, respectively) to a recently isolated hepatitis E strain from American swine.9 This finding suggests that, in the United States, hepatitis E is a zoonosis with the swine population as one of its hosts. This relationship would confirm earlier studies in Asia, where swine were also found to carry variants of the hepatitis E virus.10 Why are these two recent discoveries important for medicine in the United States? First, other sporadic, locally acquired cases of acute hepatitis may be caused by hepatitis E. Second, these back-to-back discoveries strongly suggest that a common natural host for hepatitis E is present in countries with more moderate climates. Because swine do not seem to experience any symptoms associated with infection and because symptoms in humans can be minor or absent, we now may also have an explanation for the 1 to 2% of positive hepatitis E serologic results in blood donors in the United States,11 Netherlands,12 and Italy,6 countries with large swine staples. Clearly, more research needs to be done to confirm this hypothesis. Third, in countries with more moderate climates, hepatitis E may often result in a subclinical infection. Is this variation in manifestation due to less virulent strains, and do sequence variations determine virulence? Fourth, swine may be used as an animal model for study of the disease as well as vaccine development.
Sickle cell anemia is an inherited form of anemia — a condition in which there aren't enough healthy red blood cells to carry adequate oxygen throughout your body. Normally, your red blood cells are flexible and round, moving easily through your blood vessels. In sickle cell anemia, the red blood cells become rigid and sticky and are shaped like sickles or crescent moons. These irregularly shaped cells can get stuck in small blood vessels, which can slow or block blood flow and oxygen to parts of the body. There's no cure for most people with sickle cell anemia. However, treatments can relieve pain and help prevent further problems associated with sickle cell anemia.
High blood pressure is a common condition in which the long-term force of the blood against your artery walls is high enough that it may eventually cause health problems, such as heart disease. Blood pressure is determined both by the amount of blood your heart pumps and the amount of resistance to blood flow in your arteries. The more blood your heart pumps and the narrower your arteries, the higher your blood pressure. You can have high blood pressure (hypertension) for years without any symptoms. Even without symptoms, damage to blood vessels and your heart continues and can be detected. Uncontrolled high blood pressure increases your risk of serious health problems, including heart attack and stroke. High blood pressure generally develops over many years, and it affects nearly everyone eventually. Fortunately, high blood pressure can be easily detected. And once you know you have high blood pressure, you can work with your doctor to control it.
About Us Contact Disclaimer Get Published! Follow Us Epomedicine Medical Students Clinical Discussion Cases Emergencies Blog Medical Mnemonics Clinical Skills Search Subjects Clinical examination Gastrointestinal system Internal medicine Updated on January 31, 2017 Percussion of Spleen Traube’s semilunar space Borders: Superiorly: Left 6th rib superiorly Laterally: Left midaxillary line or Left anterior axillary line Inferiorly: Left costal margin Method: Patient’s position: supine with left arm slightly abducted. Percuss: from medial to lateral Interpretation: Resonance (Normal) and Dullness (Splenomegaly) Also: Pleural effusion or mass in stomach may cause dullness in Traube’s space.