Health A-Z

Kegel Exercises

Clinical Definition Kegel exercises are a type of pelvic floor training, which is intended to strengthen the pubococcygeal muscle. It involves the alternating contraction and relaxation of the muscles of the pelvic floor. Kegel exercises are often recommended in order to prevent urinary incontinence. In Our Own Words Kegel exercises strengthen weak pelvic floor muscles

Keloid

Clinical Definition Keloids are raised, reddish (or purple) areas that form at the site of injury. In normal wound healing, fibroblasts begin multiplying to heal the wound, but in keloids, they over-multiply and continue to form irregular mounds of scar tissue. In Our Own Words Keloids are scars that form when certain cells overproduce to

Keratosis Pilaris

Clinical Definition Keratosis pilaris is a condition of the skin in which hair follicles are blocked by keratin, a protein in the skin, resulting in lesions commonly distributed on extensor aspects of the proximal limbs. Exacerbation during winter months is common. In Our Own Words Keratosis pilaris is a skin condition that looks like goose

Ketones

Clinical Definition Ketones are compounds produced for energy use when the body runs out of glucose or carbohydrates; or when levels of glucose are excessively high but cannot be used or stored as glycogen in the liver, such as in type 1 diabetes mellitus. In Our Own Words When your body isn’t getting adequate energy

Kidney Cancer

Clinical Definition Kidney cancer, or renal cancer, is rarely accompanied by symptoms in the very early stages. As it progresses, various symptoms may appear, including fatigue, unexplained weight loss, blood in the urine and persistent pain in the back, just below the ribs. Treatment options include nephrectomy (i.e., kidney removal, total or partial), radiation, chemotherapy,

Kidney Failure

Clinical Definition Kidney failure is often the final stage of chronic kidney disease, and it’s the point where kidneys can no longer do their job of eliminating waste products from the body. Diabetes and hypertension can impair kidney function, leading to chronic kidney disease (CKD). When CKD develops, the focus is on managing it with

Kidney Failure

Clinical Definition Kidney stones, or renal calculi, are small, hard ”rocks” that form when chemicals in urine become so concentrated they form solid crystals. If the stones become large, they can lodge in the urinary tract, leading to blockage, infection and severe pain. Most people affected have a chemical blood abnormality or a urine abnormality

Kleptomania

Clinical Definition Kleptomania is an impulse control disorder, still poorly understood, characterized by repeated failures to resist the impulse to steal. Once taken, the objects may be stored, given away or discarded.  A sense of tension precedes the behavior, followed by a sense of gratification. Kleptomania has been viewed from a psychodynamic perspective, with psychotherapy

Knee Pain

Clinical Definition The knee is a complex pivotal hinge joint made up of bones, ligaments, cartilage and muscles. Knee pain is a common symptom in both children and adults. The knee joint is at the junction of the fibula, tibia and patella. Menisci separate the bones of the knees. The knee capsule encases the knee

Knee Replacement

Clinical Definition Knee replacement is an orthopedic surgery performed to replace damaged articular cartilage, loss of bone structure or ligament support. The surgery involves removing a portion of bone and replacing it with a prosthetic that can be made out of cobalt chrome, titanium or polyethylene. In Our Own Words The knee is the largest

Kyphosis

Clinical Definition Kyphosis is a spinal curvature that is excessive, resulting in a back that is rounded abnormally. Some degree of spine curvature is normal, but kyphosis describes a backward bend in the upper back that is excessive. In some patients, the abnormal curves do not progress. However, when they do,   appearance issues and impact

Labor

Clinical Definition The natural and physical process of delivering a baby from the uterus, followed by the placenta, is known as labor. It involves contractions of the uterus and effacement and dilation of the cervix, which allows for passage through the birth canal. Labor is triggered by the pituitary gland hormone oxytocin, which starts uterine

Lactose intolerance

Clinical Definition Lactose intolerance is the inability to digest lactose, a milk sugar, usually due to an intestinal deficiency of the enzyme lactase. In Our Own Words When people suffer with the digestive condition lactose intolerance, they are—to varying degrees—unable to digest lactose, which is a form of sugar found in dairy products and many

Laparoscopy

Clinical Definition Laparoscopy is a surgical procedure performed with a laparoscope, a thin viewing tube that is inserted in the body through a small incision. It is considered less invasive than open surgery, which requires a much larger incision. In Our Own Words Laparoscopy is a minimally invasive surgical procedure in which a thin viewing

Lead Poisoning

Clinical Definition Lead poisoning is a condition usually occurring as a result of ingesting lead-based paint. It is especially dangerous for young children and babies, as it can damage children’s developing nervous system, and other organs, triggering behavioral problems, learning issues and other problems. Symptoms may also include hyperactivity, headaches, vomiting and fatigue. A blood

Legionnaires’ Disease

Clinical Definition Legionnaires’ disease is an infection caused by the bacteria Legionella, found naturally in the environment and typically in warm water. The disease is transmitted via inhalation of droplets of water contaminated with the bacteria and typically can lead to pneumonia. It can be treated with antibiotics. In Our Own Words Legionnaires’ disease is an infection caused

Leukemia

Clinical Definition Leukemia, from the Greek words for white (leukos) and blood (haima), is a disease that affects both children and adults. Also called a blood cancer, leukemia is a malignant disease of the blood and bone marrow (which produces all types of blood cells). Leukemia begins in immature cells of bone marrow and most

Lice

Clinical Definition Lice are blood-sucking parasites, known as Pediculus humanus capitis if on the head; Pthirus pubic if in the pubic area; andPediculus humanus corporis if elsewhere on the body. Infestations are typically the result of close person-to-person contact. Incapable of flying or hopping, the parasitic insects must crawl instead. Treatments with prescription or over-the-counter remedies can quell infestations. In

Lipoma

Clinical Definition A lipoma is a benign encapsulated neoplasm, which usually has a soft, rubbery consistency. It is composed of mature adipocytes. Lipomas are usually located in the subcutaneous layer of the skin. They are usually painless and most often do not require treatment. In Our Own Words A lipoma is a non-cancerous, abnormal mass

Lipoprotein

Clinical Definition A lipoprotein is a particle composed of lipid and protein molecules, bound together, that transports cholesterol in the blood. Low-density lipoproteins (LDL) make up the majority of the cholesterol in the body; high levels increase the risk of coronary artery disease and stroke. High-density lipoproteins (HDL) absorb cholesterol and transport it to the

Liver spots

Clinical Definition Liver spots, or solar lentigines, are often called age spots. These flat, pigmented spots are prevalent on the face, hands, arms, back and feet of fair-skinned people. The etiology is years of sun exposure. Treatments include cryotherapy, laser therapy, chemical peels, and retinoids. In Our Own Words Liver spots, also called age spots, are

Lou Gehrig’s Disease

Clinical Definition Lou Gehrig’s disease, or amyotrophic lateral sclerosis (ALS), is a progressive neuromuscular disease marked by degeneration of the motor nerve cells in the brain and spinal cord. Named after the famed baseball player who retired from the sport in 1939 due to ALS, it involves the wasting away of muscles, including those that

Low Blood Pressure

Clinical Definition Low blood pressure, or hypotension, occurs when the pressure of the blood in your arteries is much lower than normal, leading to an inadequate blood supply for the heart, brain and other body parts. Normally, a healthy blood pressure goal is less than 120/80; low pressure is typically below 90/60. Causes of severe

Low Libido

Clinical Definition Low libido, or low sexual drive, is the lack of sexual drive and diminished sexual desires, which may occur for many emotional, physical or psychosocial reasons. This common sexual dysfunction is considered a desire disorder and may be caused by a decrease in the production of estrogen (in women) and testerone (in men).

Lung Cancer

Clinical Definition Lung cancer is an uncontrolled, abnormal growth of cells that invades and destroys healthy pulmonary tissue. Symptoms can be due to the effects of the tumor in the lungs, metastases to distant sites or the activity of the cancer cells themselves. Smoking causes the vast majority of lung cancers. Treatments include chemotherapy, surgery,

Lupus

Clinical Definition Systemic lupus erythematosus (SLE) is the most common form of lupus, a serious autoimmune disease that may affect the skin, heart, joints, lungs and brain. The immune system produces antibodies to the body’s own cells, which triggers widespread inflammation and tissue damage. Anyone can be affected, but this disease often strikes women of

Lyme Disease

Clinical Definition Lyme disease is a vector-driven infectious disease caused by the Borrelia burgdorferi bacterium from the bite of a tick. The majority of cases present with acute signs and symptoms as the body mounts an immune response, including the hallmarkerythema migrans rash (it looks like a target) which occurs within one month of the bite. Bacteria spread

Lymphoma

Clinical Definition Lymphoma is a cancer of the lymph system that occurs when white blood cells, known as lymphocytes, become abnormal. In Our Own Words Lymphoma is the most common type of blood cancer. However, there are many different types of lymphoma and they fall into two main categories: Hodgkin lymphoma or non-Hodgkin lymphoma (NHL).

Macular Degeneration

Clinical Definition Macular degeneration, or age-related macular degeneration (AMD), is an ophthalmic disease that slowly destroys sharp central vision.  About 90 percent of patients have atrophic AMD, usually beginning when drusen appear in the macula. Others have neovascular or exudative AMD, triggered by abnormal blood vessel growth beneath the macula that can leak fluid and

Magnetic Resonance Imaging

Clinical Definition Magnetic resonance imaging is a scan that employs a powerful magnetic field, radio frequency pulses and a computer to create detailed pictures of bone, soft tissues, organs and other structures. Functional MRI or fMRI is newer, using the scan to measure tiny metabolic changes taking place in an active neurological area to help

Malaria

Clinical Definition Malaria is a disease caused by parasitic protozoa, which are transmitted into the bloodstream by certain types of mosquitos. Once this type of parasite moves to the liver, it multiplies and infects red blood cells. The disease can be fatal if untreated, especially in children. In Our Own Words Malaria is a parasitic

Malignant

Clinical Definition Abnormally growing cells can become cancerous, or malignant. Malignant cells may travel from their point of origin and can be fatal if left untreated. In Our Own Words Cancer generally describes a group of abnormal cells that tend to divide more rapidly than most healthy cells or lack the natural life cycle that

Manic Depressive Disorder

Clinical Definition Manic depression, known clinically as bipolar disorder, is a major mood disorder marked by episodes of depression, mixed episodes or mania. Symptoms vary but may include depressive symptoms as well as episodes with exaggerated assessment of self-importance, insomnia, pressured speech, impaired judgment, and engaging in risky activities. The disorder is managed with medication

Mastitis

Clinical Definition Mastitis, an inflammation of the breast, is most prevalent in lactating women but can affect others. The etiology is typically an infection and the condition is typically unilateral. Pain, edema and a burning sensation while breastfeeding are reported, as well as fatigue and chills. Treatments include antibiotics and over-the-counter pain medicine. In Our

Measles

Clinical Definition Measles, or rubeola, is a highly contagious vaccine-preventable viral respiratory disease caused by the virus rubeola. Droplets from the nose, mouth or throat of an infected person transmit the virus, with symptoms (e.g., red rash, fever and runny nose) typically appearing eight to 12 days after exposure. There is no cure, but bed

Melanoma

Clinical Definition Meaning “black tumor” in Latin, melanoma is the most serious form of skin cancer and can affect any part of the body. Risk of melanoma is increased through exposure to UV radiation and time spent outdoors, in tanning beds or under sun lamps. Because it affects the melanocytes (i.e. pigment cells), melanomas are

Meningitis

Clinical Definition Meningitis is an infection of the meninges, the protective membranes that surround the brain and spinal cord. Meningitis may develop in response to a number of causes, usually bacteria or a virus, but it can also be caused by certain physical injuries, cancers or drugs. In Our Own Words Although relatively rare, meningitis is

Menopause

Clinical Definition When a woman’s ovaries no longer release eggs and she hasn’t menstrated in one year, she has entered menopause. It marks the end of a woman’s reproductive period, when her body begins to produce less estrogen and progesterone. In Our Own Words A women officially enters menopause when she hasn’t had a menstrual

Menstruation

Clinical Definition Menstruation is the monthly shedding of the uterine lining that happens if a pregnancy does not occur. The typical menstrual cycle is 28 days long but can range from 21 to 35 or even 45. To menstruate three to five days is typical, but as few as two and as many as seven

Mental Breakdown

Clinical Definition Mental breakdown is a term used to describe an acute psychiatric condition  precipitated by intense stressors. Mental breakdown is not defined by the American Psychiatric Association, but is a common euphemism used to describe a reactive psychiatric condition causing impaired concentration and normal functioning. In Our Own Words A mental breakdown is a

Metabolic Syndrome

Clinical Definition Metabolic syndrome is a term used to describe a cluster of risk factors for coronary artery disease, peripheral vascular disease and diabetes. There are five characteristics of the syndrome including elevated triglyceride levels, hypertension and central obesity. Additional characteristics include insulin resistance and low high density lipoprotein cholesterol levels. In Our Own Words

Metabolism

Clinical Definition Metabolism is the chemical process occurring in the cells, which involves releasing energy from nutrients. Metabolism is an ongoing process and necessary in order to maintain life. The process of metabolism not only involves the digestion of foods but also involves processes which use energy, such as the contracting of muscles, temperature regulation,

Microvascular Coronary Dysfunction

Clinical Definition Microvascular coronary dysfunction is a cardiovascular condition that affects the capillaries and arterioles connected to the myocardium. Microvascular dysfunction interferes with proper dilation of the small vessels carrying oxygen to the myocardium. Ischemia and angina may develop as a result of microvascular coronary dysfunction. In Our Own Words The heart pumps blood to

Migraine

Clinical Definition A migraine is a headache disorder that impacts more than one in ten people. Migraines tend to be recurrent and can be moderate to severe. Pain occurs when excited brain cells trigger the trigeminal nerve to release chemicals that cause the blood vessels on the surface of the brain become dilate and become

Mitral Valve Prolapse

Clinical Definition Mitral valve prolapse is a condition in which one or both of the mitral valve flaps collapse backwards into the left atrium of the heart. As a result of the valve abnormality, a small amount of blood may regurgitate through the valve. Treatment depends on severity and symptoms, but typically ranges from monitoring

Mitral Valve Stenosis

Clinical Definition Mitral valve stenosis is a narrowing of the mitral valve orifice, impeding the filling of the left ventricle. Rheumatic heart disease is typically the cause, but the stenosis can also be linked to calcifications, infection, lupus, rheumatoid arthritis or heart disease. Those affected may have abnormal heart rhythms, chest pain and fatigue. Treatment

Mold Allergy

Clinical Definition Mold is a type of fungus that produces airborne spores. People with mold allergies have an abnormal immune response after exposure to mold spores. After inhalation of mold spores, some individuals develop an antigen-antibody reactions leading to symptoms of hypersensitivity. The most common types of molds that induce allergic reactions include Cladosporium, Penicillium

Mole

Clinical Definition A mole, or pigmented nevus, is a dermatological growth, typically unicolor, most often brown but sometimes other hues or colorless. Most moles are benign, but changes in color, height, size or shape demands evaluation, as do nevi that bleed, ooze, itch, have a scaly appearance or become tender or painful. Some types of

Mononucleosis

Clinical Definition Mononucleosis is an acute infectious disease that can cause lymphadenopathy, splenomegaly and pharyngitis. The most common causative agent is the Epstein-Barr Virus (EBV), which is a gamma-type herpes virus. Once infected with EBV, the virus remains dormant in the body and may reactivate. It is often transmitted through contact with oral secretions from

Morning Sickness

Clinical Definition Morning sickness is charactered by episodes of nausea and vomiting that occur during the first trimester of pregnancy. It is a common condition that is thought to be caused by increased levels of human chorionic gonadotropin (HGC) hormone released by the placenta into a pregnant woman’s blood system. In Our Own Words During

MRSA

Clinical Definition MRSA, or methicillin-resistant Staphylococcus Aureus, is a staph bacterium and the cause of certain skin infections in the community and serious hospital-acquired infections as well. S. aureus is common on the skin and in the nose and may be resistant to beta-lactam antibiotics (e.g., methicillin). Serious MRSA infections occur most frequently among patients in hospital settings. In

Mucous Membranes

Clinical Definition The mucous membranes, or mucosae, are moist tissues that line parts of the nose, mouth, lungs and urinary and digestive tracts. Special cells in the mucous membranes release mucus. In Our Own Words Mucous membranes, also called mucosae, are the moist tissue layers that line many structures and cavities in the body, including

Muscle Cramp

Clinical Definition A muscle cramp is the involuntary and acute contraction of a muscle. The contraction causes sudden pain for varyingdurations. Mineral depletion, nerve compression, heat and inadequate circulation can lead to muscle cramps. Muscle cramps can affect any muscle, but most commonly occur in the gastrocnemius, quadriceps and hamstrings. In Our Own Words Muscle

Myocardial Infarction

Clinical Definition Myocardial infarction, commonly called a heart attack, usually occurs when a coronary artery becomes blocked. Coronary arteries form a network of blood vessels that surround the heart and nourish it with oxygen-rich blood, which is crucial for the heart muscle to function effectively. In Our Own Words Myocardial infarction, or heart attack, happens

Myocardium

Clinical Definition The myocardium is the thick middle layer of cardiac tissue, sandwiched between the epicardium and endocardium. In Our Own Words The myocardium is the heart’s thick muscular middle layer, located between the outer layer (i.e., epicardium) and the inner layer (i.e., endocardium). The myocardium is made up of highly specialized heart muscle cells

Myopia

Clinical Definition Myopia is a refractive error, with incoming light focusing in front of the retina, rather than directly on the retina, resulting in blurred vision with objects at a distance, but not close up. Myopia runs in families, with the typical onset in childhood. Myopia progresses with age, but typically plateaus. Eyeglasses, contact lenses

Narcolepsy

Clinical Definition Narcolepsy is a chronic neurological disorder that interferes with a person’s sleep-wake cycle. In Our Own Words People who have the sleep disorder, narcolepsy, often fall asleep uncontrollably, even after having adequate sleep. During the day, you may be excessively sleepy and nearly unable to function. Sleep attacks can occur even when narcoleptics

Nasal Polyps

Clinical Definition Nasal polyps are small growths of inflamed tissue that are noncancerous and can develop on the nasal mucosa or paranasal sinuses. They are associated with prolonged inflammation of the nasal passages or sinuses from conditions such as chronic sinusitis, allergic rhinitis and asthma. If nasal polyps become too large, they can obstruct the

Necrosis

Clinical Definition Necrosis is the localized death of living tissue caused by lack of blood or oxygen and cannot be attributed to programmed cell death. In Our Own Words Necrosis is when cells die due to lack of oxygen or blood, rather than a normal, programmed cell death. Necrosis can be caused by many factors,

Nephrotic Syndrome

Clinical Definition Nephrotic syndrome, a collection of symptoms and laboratory findings that indicate renal damage, is marked by heavy protein in the urine, peripheral edema and hypoalbuminemia. Hyperlipidemia and thrombotic disease are also common. In adults, renal or systemic disease such as diabetes may be the cause; in children, minimal change disease is the major

Nervous Breakdown

Clinical Definition A nervous breakdown is technically not a medical term, but is frequently used to describe a feeling of overwhelming anxiety and stress, such that a patient is unable to maintain their previous normal level of functioning. It is commonly considered apart from any psychiatric diagnosis such as bipolar disorder, and individuals suffering from

Neti Pot

Clinical Definition A neti pot is a device used to irrigate the nasal passages and sinuses. Through the device, a saline solution is introduced into the nasal cavity in order to assist in mucociliary clearance. The solution allows allergens to be removed from the nose and sinuses. Using a neti pot may reduce nasal dryness

Neuropathy

Clinical Definition Neuropathy, also called peripheral neuropathy, describes damage to the peripheral nervous system—a network of nerves that connects the brain and spinal cord to the rest of the body. Neuropathy may be acquired from trauma, infection or systemic disease, or may be caused by medications, blood vessel problems or alcoholism. Charcot-Marie-Tooth disease is the

Nicotine Withdrawal

Clinical Definition Nicotine withdrawal occurs when someone dependent on nicotine ceases tobacco use. Nicotine is possibly as addictive as heroin, cocaine or alcohol. Withdrawal symptoms may include irritability, anxiety, concentration difficulties, insomnia and increased appetite and are linked with the level and extent of tobacco use. To relieve withdrawal symptoms medications can be prescribed. In

Night Terrors

Clinical Definition Night terrors are a type of parasomnia in which a person seems to awaken, typically from stage 3 deep sleep, in a terrified state. Those affected may appear to be awake, but also appear confused and are unable to communicate. Typically, a night terror continues for about 15 minutes, with the person then

Nocturia

Clinical Definition Nocturia is a fairly common condition in which a patient has to wake up at night to void the bladder (i.e., urinate). In Our Own Words Most people can sleep six to eight hours without needing to urinate, but patients with nocturia awaken at least once — and frequently, many additional times —

Nocturnal polyuria

Clinical Definition Nocturnal polyuria is an excessive volume of urination at nighttime. Etiologies include, excessive fluid intake (especially of caffeine or alcohol), congestive heart failure, renal insufficiency, and other conditions. Diagnosis depends on a careful health history, physical exam, evaluation of a voiding diary, tests such as urinalysis and urodynamic tests; treatment includes treating underlying

Nodules, Lung

Clinical Definition A lung nodule is a rounded opacity surrounded by lung parenchyma. It is equal to or less than 3 centimeters in diameter and usually well marginated. Lung nodules may be benign tumors, such as a hamartoma or a malignancy. Growths larger than 3 centimeters are generally classified as masses and suspected to be

Non-Hodgkin Lymphoma

Clinical Definition Non-Hodgkin lymphoma is a group of hematologic malignancies that originate in the lymphocytes. The cancerous lymphocytes multiply and do not function normally, compromising immune system functions. There are many subtypes of non-Hodgkin’s lymphoma classified according to whether they arise from T cells or B cells and whether they are indolent or aggressive. In Our Own Words

Non-Steroidal Anti-Inflammatory Drug

Clinical Definition Non-steroidal anti-inflammatory medications, or NSAIDs, are commonly recommended to relieve pain and decrease inflammation (the body’s response to injury or irritation, marked by warmth, pain, swelling). They work by blocking production of inflammatory triggers. Besides helping to reduce fever, subdue a headache or ease minor aches caused by a cold, NSAIDs are often

Norovirus

Clinical Definition Triggered by a group of Calicivirus viruses, norovirus is a viral infection that causes gastroenteritis. It is highly contagious and can be transmitted through drinking contaminated water or eating contaminated food or undercooked shellfish. In Our Own Words Norovirus is a contagious infection that causes vomiting, diarrhea and gastroenteritis (i.e., inflammation of the

Obsessive-compulsive disorder

Clinical Definition Obsessive-compulsive disorder, or OCD, is a mental health disorder characterized by anxiety-provoking, intrusive and repetitive thoughts, behaviors, or both, performed repeatedly without an individual’s control. Treatments include SSRIs and behavioral therapy, as well as options for treatment-refractory patients. In Our Own Words Obsessive-compulsive disorder, or OCD, is a disorder marked, as the name

Obstructive Sleep Apnea

Clinical Definition Obstructive sleep apnea is a serious sleep disorder that occurs when breathing is interrupted, and even ceases, repeatedly as a person sleeps, sometimes hundreds of times per single night. The pause in breathing can last 10 seconds or more. Sleep apnea occurs when the muscles in the back of the throat fail to

Occupational Asthma

Clinical Definition Occupational asthma is an obstructive lung disease caused by inhalation of specific agents in the workplace. Individuals with occupational asthma may have airway hyperresponsiveness or limited airflow due to constriction. Occupational asthma may be classified as immunoglobulin E (IgE) reaction asthma, which triggers an immune response. Asthma symptoms develop after a latency period.

Omega-3 Fatty Acids

Clinical Definition Omega-3 fatty acids or n-3 fatty acids are polyunsaturated fats, termed essential, as the body cannot produce them. The primary dietary source is fish such as salmon. Fish contain two kinds of omega-3s, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Omega-3s are a natural anticoagulant, plaque inhibitor and help decrease triglycerides. In Our

Omega-6 Fatty Acids

Clinical Definition Omega-6 fatty acids, or n-6 fatty acids, are polyunsaturated, essential fatty acids that must be gotten from food. Found in some vegetables oils, nuts and seeds, omega-6s along with omega-3 fatty acids have a crucial role in cerebral function and normal growth and development. In Our Own Words Omega-6 fatty acids, also called

Osteoarthritis

Clinical Definition Osteoarthritis, a degenerative joint disease, is more prevalent with age as inflammation and joint injury cause a breakdown of cartilage tissue, triggering pain, edema and deformity. Treatment may include medication, exercise, heat and cold therapy, weight loss, supportive devices and surgery. In Our Own Words Osteoarthritis is a disease of the joints, more

Osteogenesis Imperfecta

Clinical Definition Osteogenesis imperfecta, also known as brittle bone disease, is a genetic disorder characterized by bones that break easily and often with no cause. People with the disorder either lack enough collagen or have poor quality collagen, the major protein in the body’s connective tissue. The features of osteogenesis imperfecta vary among individuals, from

Ovarian Cancer

Clinical Definition Ovarian carcinoma is a malignant tumor that most often originates in the epithelial cells of the ovaries, with 90 percent of affected women older than 40, and many in their 50s and 60s. The etiology is not known, but women who have an early menopause, family history of ovarian cancer or who are

Ovaries

Clinical Definition Ovaries are the pair of female reproductive glands responsible for producing ova, or egg cells. The ovaries are located in the pelvis on each side of the uterus close to the opening of the oviducts. The utero-ovarian ligament, which is a band of fibrous tissue, holds the ovaries in place. Ovaries in post-pubertal

Overactive Bladder

Clinical Definition Overactive bladder, or OAB, is a constellation of symptoms including urinary urgency, urinary frequency and nocturnal urination at least twice. The condition is more common with age. Treatments include lifestyle modification, behavioral therapy and antimuscarinic drug therapy. In Our Own Words Overactive bladder, also known as OAB, is the frequent urge to urinate,

Overuse Injury

Clinical Definition An overuse injury is any type of injury to the joints or bones from repetitive movements. Participating in certain sports can put stress on the bones, joints, ligaments or tendons in the body. The repetitive stress placed on the same body part can cause micro-trauma, such as tears in the muscle fibers. Over

Painful Intercourse

Clinical Definition Painful intercourse has a number of possible causes. It may be the result of gynecologic problems, such as cysts or endometriosis, or lubrication issues caused by menopause or lack of arousal. It also may stem from emotional issues relating to relationship problems or anxiety. In Our Own Words Painful intercourse is something many

Palpitations

Clinical Definition Heart palpitations are a perceived abnormality of heartbeat, including tachycardia or extrasystole. Palpitations can occur at any time, including during performance of daily activities. The etiology is diverse, ranging from stress, anxiety and other emotions to pregnancy, caffeine ingestion and certain medical conditions. Palpitations may or may not be linked to a serious

Pancreatitis

Clinical Definition Pancreatitis is an inflammatory process of the pancreas. The pancreas secretes digestive enzymes, which normally don’t become active until they reach the small intestines. When pancreatitis develops, enzymes prematurely activate in the pancreas and attack it. This causes pancreatic tissue damage and bleeding. In Our Own Words Pancreatitis, or inflammation of the pancreas,

Panic Attack

Clinical Definition A panic attack, provoked by catastrophic misinterpretations of bodily sensations, is a core feature of the psychiatric condition known as panic disorder.  Marked by a period of intense fear or discomfort that strikes suddenly, often in a milieu where nothing threatening exists, the sense of danger is so intense during a panic attack

Parasympathetic Nervous System

Clinical Definition The parasympathetic nervous system is a subdivision of the autonomic nervous system. It consists of nerve fibers, which originate in the brain stem. It returns the body to homeostasis. The parasympathetic nervous system promotes slowing of the heart rate, flowing of gastric juices and muscular activity of the alimentary tract. In Our Own

Parkinson’s Disease

Clinical Definition Parkinson’s disease is a progressive motor system disorder. The specific etiology is not known. Symptoms are associated with progressive demise of dopamine producing neurons in the brain. Although it can develop earlier, the onset of the disease is generally after 50 years of age. It is characterized by bradykinesia, postural instability, rigidity and

Pathogen

Clinical Definition A pathogen is any microorganism or agent that invades another organism and causes disease or illness in its host. Pathogens are transmitted to the host via various pathways and have varying degrees of virulence. In Our Own Words A pathogen is any organism that can enter the body and make you sick. Pathogens

Pelvic Inflammatory Disease

Clinical Definition Pelvic inflammatory disease is an infection of the female pelvic region that may involve the fallopian tubes, uterus and ovaries. The disease occurs as a complication of a sexually transmitted infection, commonly caused by the organisms Neisseria gonorrhoeae and chlamydia trachomatis. Pelvic inflammatory disease can lead to the formation of fibrous tissue affecting

Peptic Ulcer

Clinical Definition A peptic ulcer is an ulceration of the alimentary mucosa. It usually develops in the duodenum or the stomach, which are exposed to gastric secretions. An infection with the bacterium Helicobacter pylori is believed to contribute to a large percentage of peptic ulcers. In Our Own Words A peptic ulcer is a lesion

Periodontitis

Clinical Definition Periodontitis is chronic inflammation of the periodontal tissue in the mouth due to bacteria. Tissue affected can include the gingiva, bone and root of the tooth. In Our Own Words Periodontitis is a stage of gum disease. When bacteria in plaque start to build up, it causes gingivitis. First the gums become inflamed,

Peripheral Artery Disease

Clinical Definition Peripheral artery disease is a circulatory disorder that causes a narrowing and stiffening of the peripheral arteries. It most often involves the arteries of the pelvis or the lower extremities, compromising blood flow. Complications can include gangrene and critical limb ischemia. Usually, the condition is due to atherosclerosis. Peripheral artery disease increases a

Peripheral Nerve Disease

Clinical Definition Peripheral nerve disease is any one of a group of disorders that causes peripheral neuropathy and interferes with proper nerve cell functioning. Various nerves, such as the sensory, motor and autonomic nerves, may also be involved depending on the disease and the underlying cause. Sensation and muscle functioning may be impacted to varying

Pink Eye

Clinical Definition Pink eye, medically known as conjunctivitis, is a common eye condition involving inflammation of the conjunctiva, or inner lining of the eyelid. Conjunctivitis may be caused by a virus, bacteria or allergens and is highly contagious. Additionally, foreign bodies in the eye can also irritate the conjunctiva, as well as air pollution, smoke,

Plantar Fasciitis

Clinical Definition Plantar fasciitis is a common foot injury especially among athletic people. It occurs when the strong band of tissue known as the plantar fascia, which supports the foot’s arch, becomes irritated, inflamed and painful. The plantar fascia is a ligament that lies directly beneath the skin on the bottom of your foot; it

Pleura

Clinical Definition The pleura is the serous membrane, which lines the walls of the pulmonary cavities and lungs. It is composed of a single layer of mesothelial cells. The pleura is divided into two areas including the visceral pleura, which envelops the lungs, and the partial pleura, which surrounds the thorax, diaphragm and chest wall.

Pleural Effusion

Clinical Definition Pleural effusion is an accumulation of excess fluid between the pulmonary pleural layers. A pleural effusion can occur without symptoms; alternatively there may be symptoms including chest pain, nonproductive cough and dyspnea. This excess fluid can be described as transudative (watery) or exudative (protein-rich), which can help in determining the etiology. In Our

Pneumonia

Clinical Definition Pneumonia is a potentially fatal illness that causes consolidation of the affected segment of the lung and inflammation of the lung parenchyma. Pneumonia may be lobular or segmental. Bacteria and viruses are the most common causative agents, although fungi and aspiration of food can also lead to pneumonia. The infection is characterized by

Polyuria

Clinical Definition Polyuria is excessive urination beyond the typical daily output of three liters, or just over three quarts a day. Polyuria is more prevalent with advancing age and is caused by a number of conditions, including congestive heart failure, uncontrolled diabetes and excessive intake of fluids during the day. In Our Own Words Polyuria

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