Kids Research Express

Osteomyelitis, term applied to any inflammation of bone or bone marrow, usually caused by infection by such microorganisms as Staphylococcus aureus, various streptococci, Mycobacterium tuberculosis, and a host of others, as well as several fungi. The microorganisms generally reach the bone through the bloodstream from infection elsewhere. Occasionally osteomyelitis occurs by direct infection after surgery, after a compound fracture, or as a result of trauma. Osteomyelitis, especially bacterial, may occur as an acute disease. Common symptoms include chills followed by fever, with acute pain and swelling above the site of inflammation. The inflammation begins in the marrow cavity and causes softening and erosion of the long bones, often with the formation of pus-containing abscesses, and soon spreads over the entire bone, with consequent death of the hard portions of the bone. Chronic osteomyelitis, as is often seen in tuberculosis, fungus infections, or in patients with bacterial infe

Obsessive-Compulsive Disorder, mental illness in which a person experiences recurrent, intrusive thoughts (obsessions) and feels compelled to perform certain behaviors (compulsions) again and again. Most people have experienced bizarre or inappropriate thoughts and have engaged in repetitive behaviors at times. However, people with obsessive-compulsive disorder find that their disturbing thoughts and behaviors consume large amounts of time, cause them anxiety and distress, and interfere with their ability to function at work and in social activities. Most people with this disorder recognize that their obsessions and compulsions are irrational but cannot suppress them. Treatment for obsessive-compulsive disorder includes psychotherapy, psychoactive drugs, or both. Mental health professionals consider exposure and response prevention, a type of cognitive-behavioral therapy, to be the most effective form of psychotherapy for this disorder. Medications to treat obsessive-compulsive disorde

Obesity, medical condition characterized by storage of excess body fat. The human body naturally stores fat tissue under the skin and around organs and joints. Fat is critical for good health because it is a source of energy when the body lacks the energy necessary to sustain life processes, and it provides insulation and protection for internal organs. But the accumulation of too much fat in the body is associated with a variety of health problems. A calorie is the unit used to measure the energy value of food and the energy used by the body to maintain normal functions. When the calories from food intake equal the calories of energy the body uses, weight remains constant. But when a person consumes more calories than the body needs, the body stores those additional calories as fat, causing subsequent weight gain. Consuming about 3,500 calories more than what the body needs results in a weight gain of 0.45 kg (1 lb) of fat. Obesity can become a chronic lifelong condition caused by ove

Neuritis, inflammation of peripheral nerves, characterized by sensory or motor disturbances that may take the form of pain (often burning), numbness, tingling (or pins-and-needles) sensations, hypersensitivity, or anesthesia, in the area supplied by the involved nerve; weakness or paralysis of the muscles innervated by the involved nerve may also take place. It is generally the result of such localized causes as injuries, pressure from arthritis involving the spine at the area where the nerve root exits, adjacent tumors, or prolonged exposure to extreme cold. Neuritis may also involve several nerves in different parts of the body. This type of neuritis usually affects the extremities. Infectious diseases, such as typhoid fever, malaria, syphilis, or tuberculosis, and diabetes, heavy-metal poisoning, alcoholism, vitamin deficiencies associated with pregnancy, beriberi, and pellagra are among the causes of certain types of neuritis.

Neuralgia, recurrent pain along the path of a sensory nerve. Neuralgia may be caused by a disorder that affects a nerve, such as tooth decay or carpal tunnel syndrome, or it may accompany such diseases as diabetes mellitus or certain vitamin deficiencies. In some cases the cause of neuralgia cannot be determined. Whatever the cause, the affected nerve does not become inflamed and its tissues are not damaged or destroyed. Trigeminal neuralgia is one of the most common forms of neuralgia, involving the trigeminal nerve, which carries sensation from the face, eyes, nose, mouth, and jaws to the brain. Trigeminal neuralgia is characterized by overwhelming sensations of stabbing pain that may be momentary or may last for minutes or hours. When it is short-lived, the condition is also known as tic douloureux. Trigeminal neuralgia may be relieved by analgesics such as aspirin, ibuprofen, and acetaminophen. In severe cases, surgery may be performed to reduce pressure on the nerve or to sever i

Myasthenia Gravis, chronic disease marked by progressive weakness and abnormally rapid fatigue of the voluntary muscles . The muscles affected include those used in walking, breathing, chewing, and talking. A characteristic sign of the disease is drooping eyelids. Myasthenia gravis most often affects women between the ages of 20 and 30, but it can strike anyone after adolescence; after 40, it actually afflicts more men than women. Myasthenia gravis is a noninherited autoimmune disease characterized by the presence of antibodies in the blood that destroy muscle-cell sites for the reception of acetylcholine molecules. Acetylcholine normally transmits signals between nerves and muscles, so when its receptors are destroyed it cannot induce muscle contractions. No cure for the disease yet exists, but it can be treated with drugs called anticholinesterases. These drugs are capable of inhibiting an enzyme, acetylcholinesterase, that breaks down acetylcholine in the body. Myasthenia gravis m

Muscular Dystrophy, crippling disease characterized by gradual wasting of skeletal muscle . As the disease progresses, symptoms include increased weakness and loss of muscle mass and function. Eventually a person with muscular dystrophy needs to use a wheelchair to move around. Four clinical forms of the disease are recognized, based on pattern of inheritance, age when symptoms are first noted, and distribution of the muscles earliest involved. Microscopic abnormalities of skeletal muscle are found in each type. Muscular dystrophy has its origin in a genetic mutation, but the biochemical steps by which this genetic defect manifests itself in the degenerative process in the muscle are not known. Because specific treatment is not available, general measures, including physical and occupational therapy, are used. Genetic tests for mutations in the different genes causing muscular dystrophy provide rapid and accurate diagnosis for patients.