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Overview Aseptic meningitis is an illness characterized by serous inflammation of the linings of the brain (i.e., meninges), usually with an accompanying mononuclear pleocytosis. Clinical manifestations vary, with headache and fever predominating. The illness is usually mild and runs its course without treatment; however, some cases can be severe and …

What is an anal fissure? An anal fissure is a tear in the lining of the lower rectum (anal canal) that causes pain during bowel movements. Anal fissures don’t lead to more serious problems. Most anal fissures heal with home treatment after a few days or weeks. These are called …

Introduction Adenoviruses (Adenovirus infection) are a group of common viruses that infect the lining of your eyes, airways and lungs, intestines, urinary tract, and nervous system. They’re common causes of fever, coughs, sore throats, diarrhea, and pink eye. Infections happen in children more often than in adults, but anyone can …

Description – Atrial Fibrillation Atrial fibrillation is an irregular and often rapid heart rate that can increase your risk of strokes, heart failure, and other heart-related complications. During atrial fibrillation, the heart’s two upper chambers (the atria) beat chaotically and irregularly — out of coordination with the two lower chambers …

Definition Anthrax, also called malignant pustule or woolsorters disease, acute, infectious, febrile disease of animals and humans caused by Bacillus anthracis, a bacterium that under certain conditions forms highly resistant spores capable of persisting and retaining their virulence for many years. Although it is most commonly affects grazing animals such …

Definition Alcohol poisoning can occur when a person drinks large quantities of alcohol, including beer, wine, and liquor, in a relatively short time. As the amount of alcohol in the bloodstream increases, the liver can’t break down the alcohol and remove its toxins from the blood quickly enough. The excess …

Definition Arteriovenous malformation is a congenital disorder (present from birth) characterized by a complex, tangled web of arteries and veins in which there are a short circuit and high pressure due to arterial blood flowing rapidly in the veins. An AVM may occur in the brain, brainstem or spinal cord. …

What Is Apraxia? Apraxia is a poorly understood neurological condition. People who have it find it difficult or impossible to make certain motor movements, even though their muscles are normal. Milder forms of apraxia are known as dyspraxia. Apraxia can occur in a number of different forms. One form is …