Articles

Find answers to your health-related questions in our Ilustrated Health Encyclopedia

  • Disease

    Ulcerative colitis

    The esophagus, stomach, large and small intestine, aided by the liver, gallbladder and pancreas convert the nutritive components of food into energy and break down the non-nutritive components into waste to be excreted.

    Ulcerative colitis is a condtion in which the lining of the large intestine (colon) and rectum become inflamed. Ulcerative colitis is a form of inflammatory bowel disease (IBD). Crohn’s disease is a related condition.

  • Symptoms

    Ulcers

    An ulcer is a crater-like lesion on the skin or mucous membrane caused by an inflammatory, infectious, or malignant condition. To avoid irritating an ulcer a person can try eliminating certain substances from their diet such as caffeine, alcohol, aspirin, and avoid smoking.  Patients can take certain medicines to suppress the acid in the stomach causing the the erosion of the stomach lining.  Endoscopic therapy can be used to stop bleeding from the ulcer.

    An ulcer is a crater-like sore on the skin or . Ulcers form when the top layers of skin or tissue have been removed. They can occur in the mouth, stomach, and other parts of the body.

  • Disease

    Ulnar nerve dysfunction

    The ulnar nerve originates from the brachial plexus and travels down arm.  The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where it crosses the elbow, so prolonged pressure on the elbow or entrapment of the nerve may cause damage. Damage to the ulnar nerve may involve impaired movement or sensation in the wrist and hand.

    Ulnar nerve dysfunction is a problem with the nerve that travels from the shoulder to the hand. This is called the ulnar nerve. It helps you move your hand and wrist.

  • Test

    Ultrasound

    Ultrasound in pregnancy

    A pregnancy ultrasound is an imaging test that uses sound waves to create a picture of how a baby is developing in the womb. It is also used to check the female pelvic organs during pregnancy.

  • Test

    Ultrasound

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, and CT scan, it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce an image and do not expose the individual to radiation. The procedure is painless and safe.

    Ultrasound uses high-frequency sound waves to make images of organs and structures inside the body.

  • Special Topic

    Umbilical catheters

    Umbilical catheter

    A catheter is a long, soft, hollow tube. An umbilical artery catheter (UAC) allows blood to be taken from an infant at different times, without repeated needle sticks. It can also be used to continuously monitor a baby’s blood pressure. An umbilical artery catheter is most often used if: The baby ...

  • Special Topic

    Umbilical cord care in newborns

    The umbilical cord connects the baby to the mother's placenta. During fetal development in the womb, the umbilical cord is the lifeline to the baby supplying nutrients. After birth, the cord is clamped and cut. Eventually between 1-3 weeks the cord will become dry and will naturally fall off. During the time the cord is healing it should be kept as clean and as dry as possible.

    When your baby is born the umbilical cord is cut and there is a stump left. The stump should dry and fall off by the time your baby is 5 to 15 days old. Keep the stump clean with gauze and water only. Sponge bathe the rest of your baby, as well. Do not put your baby in a tub of water until the stump ...

  • Disease

    Umbilical hernia

    An umbilical hernia is a protrusion of the peritoneum and fluid, omentum, or a portion of abdominal organ(s) through the umbilical ring.  The umbilical ring is the fibrous and muscle tissue around the navel (belly-button). Small hernias usually close spontaneously without treatment by age 1 or 2. Umbilical hernias are usually painless and are common in infants.

    An umbilical hernia is an outward bulging (protrusion) of the lining of the abdomen or part of the abdominal organ(s) through the area around the belly button.

  • Surgery

    Umbilical hernia repair

    Umbilical hernia repair is surgery to repair an . An umbilical hernia is a sac (pouch) formed from the inner lining of your belly (abdominal cavity) that pushes through a hole in the abdominal wall at the belly button.

  • Injury

    Unconsciousness - first aid

    Unconsciousness is when a person is unable to respond to people and activities. Often, this is called a coma or being in a comatose state. Other changes in awareness can occur without becoming unconscious. Medically, these are called “altered mental status” or “changed mental ...

  • Self-Care Instructions

    Understanding cholesterol results

    Cholesterol is a soft, waxy substance that is present in all parts of the body including the nervous system, skin, muscle, liver, intestines, and heart. It is made by the body and obtained from animal products in the diet.  Cholesterol is manufactured in the liver and is needed for normal body functions including the production of hormones, bile acid, and Vitamin D.  Excessive cholesterol in the blood contributes to atherosclerosis and subsequent heart disease. The risk of developing heart disease or atherosclerosis increases as the level of blood cholesterol increases.

    Cholesterol test results; LDL test results; VLDL test results; HDL test results

  • Disease

    Undescended testicle

    The male reproductive structures include the penis, the scrotum, the seminal vesicles and the prostate.

    Undescended occurs when one or both testicles fail to move into the before birth.

  • Surgery

    Undescended testicle repair

    The male reproductive structures include the penis, the scrotum, the seminal vesicles and the prostate.

    repair is surgery to correct testicles that have not dropped down into the correct position in the scrotum.

  • Disease

    Unilateral hydronephrosis

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Unilateral hydronephrosis is swelling of one kidney due to a backup of urine.

  • Disease

    Unstable angina

    Angina is a specific type of pain in the chest caused by inadequate blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).

    Unstable angina is a condition in which your heart doesn’t get enough blood flow and oxygen. It may lead to a heart attack. Angina is a type of chest discomfort caused by poor blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).

  • Disease

    UPJ obstruction

    The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and stimulating red blood cell production.

    Ureteropelvic junction (UPJ) obstruction is a blockage at the point where part of the kidney attaches to one of the tubes to the bladder (ureters). This blocks the flow of urine out of the kidney.

  • Test

    Upper airway biopsy

    An upper airway biopsy is obtained by using a flexible scope called a bronchoscope.  The scope is passed down through the mouth and throat and a small piece of tissue is removed and sent to the laboratory. This test may be performed when an abnormality of the upper airway is suspected. It may also be performed as part of a bronchoscopy when abnormalities include the upper airway as well as the lung tissue.

    Upper airway biopsy is surgery in which a small piece of tissue is removed from the nose, mouth, and throat area for examination.

  • Test

    Upper GI and small bowel series

    An upper GI series is performed to examine the esophagus, stomach, and small intestine. The purpose of the test is to detect abnormalities in those areas.

    An upper GI and small bowel series is a set of taken to examine the esophagus, stomach, and small intestine. is a related test.

  • Test

    Urea nitrogen urine test

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urine urea nitrogen is a test that measures the amount of urea in the urine. Urea nitrogen is a waste product resulting from the breakdown of protein in the body.

  • Test

    Ureteral retrograde brush biopsy

    The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and stimulating red blood cell production.

    Ureteral retrograde brush biopsy is a procedure that takes a small sample of tissue from the lining of the kidney or ureter (tube that connects a kidney to the bladder). The tissue is sent to a lab for testing.

  • Disease

    Ureterocele

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    A ureterocele is a swelling at the bottom of one of the tubes (ureters) that carry urine from the kidney to the bladder. The swollen area can block urine flow. A ureterocele is a birth defect.

  • Surgery

    Ureteroscopy

    Ureteroscopy uses a small lighted tube to examine the ureters. Ureters are the tubes that connect the kidneys to the bladder. This procedure can help diagnose and treat problems in the urinary tract, such as kidney stones.

  • Test

    Urethral discharge culture

    Urethral discharge culture is a laboratory test done on men and boys to identify germs in the urethra that may be causing an infection (). The urethra is the tube that drains urine from the bladder.

  • Disease

    Urethral stricture

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urethral stricture is an abnormal narrowing of the tube that carries urine out of the body from the bladder (urethra).

  • Disease

    Urethritis

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urethritis is swelling and irritation (inflammation) of the urethra. The urethra is the tube that carries urine from the body.

  • Disease

    Urge incontinence

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urge incontinence occurs when you have a strong, sudden need to urinate. The bladder then squeezes, or spasms, and you lose urine.

  • Test

    Uric acid - blood

    Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.

    Uric acid is a chemical created when the body breaks down substances called purines. Purines are found in some foods and drinks. These include liver, anchovies, mackerel, dried beans and peas, and beer. Most uric acid dissolves in blood and travels to the kidneys. From there, it passes out in urine. ...

  • Test

    Uric acid - urine

    Urea nitrogen urine test is performed to check for the amount of urea in urine.  Urine is collected over a 24 hour period and is sent to the laboratory for testing.  This test is mainly used to assess the amount of dietary protein needed by severely ill patients.

    The urine uric acid test measures the level of uric acid in urine. Uric acid level can also be checked using a .

  • Test

    Urinalysis

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds that pass through the urine.

  • Test

    Urinary casts

    The urinary system is made up of the kidneys, ureters, urethra and bladder.

    Urinary casts are tiny tube-shaped particles that can be found when urine is examined under the microscope during a test called . Urinary casts may be made up of white blood cells, red blood cells, kidney cells, or substances such as protein or fat. The content of a cast can tell your health care ...

  • Special Topic

    Urinary catheter - infants

    A urinary catheter is a small, soft tube placed in the bladder. This article addresses urinary catheters in babies. Why is a urinary catheter used? Babies need urinary catheters if they are not making much urine. Babies can have low urine because they: Have low blood pressure Have an abnormally ...

  • Special Topic

    Urinary catheters

    A urinary catheter is a tube placed in the body to drain and collect urine from the bladder.

  • Questions To Ask Your Doctor

    Urinary catheters - what to ask your doctor

    You have an indwelling catheter (tube) in your bladder. This means the tube is inside your body. This catheter drains urine from your bladder into a bag outside your body. Below are some questions you may want to ask your doctor or nurse to help you take care of your catheter.

  • Symptoms

    Urinary incontinence

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urinary (or bladder) incontinence happens when you are not able to keep urine from leaking out of your urethra, the tube that carries urine out of your body from your bladder. You may leak urine from time to time. Or, you may not be able to hold any urine. The three main types of urinary ...

  • Surgery

    Urinary incontinence - injectable implant

    Injectable implants are injections of material into the urethra to help control urine leakage () caused by a weak urinary sphincter. The sphincter is a muscle that allows your body to hold the urine in the bladder. If your sphincter muscle stops working well you will have urine leakage.

  • Surgery

    Urinary incontinence - retropubic suspension

    Retropubic suspension is surgery to help control . This is urine leakage that happens when you laugh, cough, sneeze, lift things, or exercise. The surgery helps close your urethra and bladder neck. The urethra is the tube that carries urine from the bladder to the outside. The bladder neck is the ...

  • Surgery

    Urinary incontinence - tension-free vaginal tape

    Placement of tension-free vaginal tape is surgery to help control . This is urine leakage that happens when you laugh, cough, sneeze, lift things, or exercise. The surgery helps close your urethra and bladder neck. The urethra is the tube that carries urine from the bladder to the outside. The ...

  • Surgery

    Urinary incontinence - vaginal sling procedures

    Vaginal sling procedures are types of surgeries that help control . This is urine leakage that happens when you laugh, cough, sneeze, lift things, or exercise. A vaginal sling procedure helps close your urethra and bladder neck. The urethra is the tube that carries urine from the bladder to the ...

  • Questions To Ask Your Doctor

    Urinary incontinence - what to ask your doctor

    You have urinary incontinence. This means that you are not able to keep urine from leaking from your urethra, the tube that carries urine out of your body from your bladder. Urinary incontinence may occur as you get older. It can also develop after a surgery or childbirth. You can do many things to ...

  • Special Topic

    Urinary incontinence products

    The urinary system is made up of the kidneys, ureters, urethra and bladder.

    There are many products to help you manage . You can decide which product to choose based on: How much urine you lose Comfort Cost Durability How easy it is to use How well it controls odor How often you lose urine throughout the day and night INSERTS AND PADS You may have tried using sanitary pads ...

  • Self-Care Instructions

    Urinary incontinence products - self-care

    Adult diapers; Disposable urinary collection devices

  • Disease

    Urinary tract infection - adults

    A catheter (a hollow tube, often with an inflatable balloon tip) may be inserted into the urinary bladder when there is a urinary obstruction, following surgical procedures to the urethra, in unconscious patients (due to surgical anesthesia, coma, etc.), or for any other problem in which the bladder needs to be kept empty (decompressed) and urinary flow assured.

    A urinary tract infection, or UTI, is an infection of the urinary tract. The infection can occur at different points in the urinary tract including: Bladder — an infection in the bladder is also called or a bladder infection. Kidneys — an infection of one or both kidneys is called or a ...

  • Disease

    Urinary tract infection - children

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    A urinary tract infection (UTI) is an infection of the urinary tract. This article discusses UTIs in children. The infection can affect different parts of the urinary tract, including the: Bladder, also called cystitis Kidneys, also called pyelonephritis Urethra — the tube that empties urine ...

  • Self-Care Instructions

    Urinary tract infection in children - aftercare

    Symptoms of should begin to improve within 1 to 2 days.

  • Self-Care Instructions

    Urinary tract infection in children - aftercare

    If your child has a urinary tract infection and has been lethargic, irritable, or not drinking or eating well, these symptoms should begin to improve in 1 – 2 days after treatment begins. (Note: if your child has a brain or nervous system disorder or abnormal changes or defects in their ...

  • Self-Care Instructions

    Urinary tract infection in women - self-care

    Most urinary tract infections (UTI) are caused by bacteria that enter the urethra and travel to the bladder. This can lead to infection, most commonly in the bladder itself. At times, the infection can spread to the kidneys. Common symptoms include: Bad urine odor Pain or burning when you ...

  • Symptoms

    Urinating more at night

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Normally, the amount of urine your body produces decreases at night. This allows most people to sleep 6 to 8 hours without having to urinate. Some people wake up from sleep more often to urinate during the night. This can disrupt sleep cycles.

  • Symptoms

    Urination - difficulty with flow

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Difficulty starting or maintaining a urine stream is called urinary hesitancy.

  • Symptoms

    Urination - excessive amount

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Excessive amount of urination means that your body makes larger than normal amounts of urine each day.

  • Symptoms

    Urination - painful

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Painful urination describes any pain, discomfort, or burning sensation when passing urine.

  • Symptoms

    Urine - abnormal color

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    The usual color of urine is straw-yellow. Abnormally colored urine may be cloudy, dark, or blood-colored.

  • Symptoms

    Urine - bloody

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Blood in your urine is called hematuria. The amount may be very small and only detected with urine tests or under a microscope. In other cases, the blood is visible. It often turns the toilet water red or pink. Or, you may see spots of blood in the water after urinating.

  • Test

    Urine 24-hour volume

    A "clean-catch" urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. A small amount of urine should initially fall into the toilet bowl before it is collected (this clears the urethra of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. The container is then given to the health care provider.

    The urine 24-hour volume test measures the amount of urine produced in a day. The amount of creatinine, protein, and other chemicals released into the urine during this period is often tested.

  • Test

    Urine chemistry

    Urine is the liquid waste product excreted by the kidneys.  It is stored in the bladder until it is emptied out through the urethra.

    Urine chemistry is a group of one or more tests done to check the chemical content of a urine sample.

  • Test

    Urine collection - infants

    It is sometimes necessary to get a urine sample from a baby to do testing. Most the time, urine is collected in the doctor’s office. A sample can also be collected at home.

  • Test

    Urine concentration test

    The urine concentration test is a test that measures whether the kidneys are conserving or excreting water properly.  A sample of urine is retrieved and tested for its specific gravity.

    A urine concentration test measures the ability of the kidneys to appropriately conserve or excrete water.

  • Test

    Urine culture

    A "clean-catch" urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. A small amount of urine should initially fall into the toilet bowl before it is collected (this clears the urethra of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. The container is then given to the health care provider.

    A urine culture is a lab test to check for bacteria or other germs in a urine sample. See also:

  • Test

    Urine culture - catheterized specimen

    A catheter (a hollow tube, often with an inflatable balloon tip) may be inserted into the urinary bladder when there is a urinary obstruction, following surgical procedures to the urethra, in unconscious patients (due to surgical anesthesia, coma, etc.), or for any other problem in which the bladder needs to be kept empty (decompressed) and urinary flow assured.

    Catheterized specimen urine culture is a laboratory test that looks for germs in a urine sample.

  • Self-Care Instructions

    Urine drainage bags

    Leg bag

  • Test

    Urine drug screen

    A "clean-catch" urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. A small amount of urine should initially fall into the toilet bowl before it is collected (this clears the urethra of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. The container is then given to the health care provider.

    A urine drug screen is used to detect illegal and some prescription drugs in the urine.

  • Test

    Urine melanin

    A "clean-catch" urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. A small amount of urine should initially fall into the toilet bowl before it is collected (this clears the urethra of contaminants). Then, in a clean container, catch about 1 to 2 ounces of urine and remove the container from the urine stream. The container is then given to the health care provider.

    Urine melanin is a test to determine the abnormal presence of in the urine.

  • Symptoms

    Urine odor

    Urine odor refers to the smell from your urine. Urine odor varies. Most of the time, urine does not have a strong smell if you are healthy and drink plenty of fluids.

  • Symptoms

    Urine output - decreased

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups).

  • Test

    Urine pH test

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    A urine pH test measures the level of acid in urine.

  • Test

    Urine specific gravity test

    The female and male urinary tracts are relatively the same except for the length of the urethra.

    Urine specific gravity is a laboratory test that measures the concentration of all chemical particles in the urine.

  • Test

    Uroflowmetry

    Urine is the liquid waste product excreted by the kidneys.  It is stored in the bladder until it is emptied out through the urethra.

    Uroflowmetry is a test that measures the volume of urine released from the body, the speed with which it is released, and how long the release takes.

  • Self-Care Instructions

    Urostomy - stoma and skin care

    Ostomy care – urostomy

  • Self-Care Instructions

    Urostomy pouches and supplies

    Cystectomy – urostomy; Urostomy bag; Ostomy appliance; Urinary ostomy

  • Disease

    Urticaria pigmentosa

    Dermatographism is a condition where lightly scratching the skin raises wheals or welts. Histamine is released, which causes the small blood vessels (capillaries) to dilate, producing redness and localized swelling.

    Urticaria pigmentosa is a skin disease that produces patches of darker skin () and very bad . Hives can develop when skin areas are rubbed.

  • Special Topic

    Use of restraints

    Restraint devices

  • Self-Care Instructions

    Using a cane

    It is important to start walking soon after surgery for a leg injury. But you will need support while your leg is healing. A cane can be used for support. It may be a good choice if you only need a little help with balance and stability, or if your leg is only a little weak or painful. The 2 main ...

  • Self-Care Instructions

    Using a walker

    It is important to start walking soon after a leg injury or surgery. But you will need support while your leg is healing. A walker can give you support and help you keep stable as you start to walk again. There are many types of walkers. Some walkers have no wheels, 2 wheels, or 4 wheels. You can ...

  • Self-Care Instructions

    Using an incentive spirometer

    An incentive spirometer is a device used to help you keep your lungs healthy after surgery or when you have a lung illness, such as . The incentive spirometer teaches you how to take slow deep breaths. After surgery, it may be too painful to take deep breaths. You may also feel too weak to take deep ...

  • Self-Care Instructions

    Using oxygen at home

    Oxygen – home use

  • Questions To Ask Your Doctor

    Using oxygen at home - what to ask your doctor

    Because of problems with your lungs or heart, you will need to use oxygen in your home. Below are some questions you may want to ask your doctor or nurse to help you use your oxygen.

  • Self-Care Instructions

    Using your shoulder after replacement surgery

    Joint replacement surgery – using your shoulder; Shoulder replacement surgery – after

  • Self-Care Instructions

    Using your shoulder after surgery

    Shoulder surgery – using your shoulder; Shoulder surgery – after

  • Surgery

    Uterine artery embolization

    Uterine artery embolization (UAE) is a procedure to treat without surgery. Uterine fibroids are noncancerous (benign) tumors that develop in the uterus (womb). During the procedure, the blood supply of the fibroids is cut off. This causes the fibroids to shrink.

  • Disease

    Uterine fibroids

    External structures of the female reproductive anatomy include the labium minora and majora, the vagina and the clitoris. Internal structures include the uterus, ovaries and cervix.

    Uterine fibroids are tumors that grow in a woman’s womb (uterus). These growths are not cancer (benign).

  • Disease

    Uterine prolapse

    External structures of the female reproductive anatomy include the labium minora and majora, the vagina and the clitoris. Internal structures include the uterus, ovaries and cervix.

    Uterine prolapse occurs when the womb (uterus) drops down and presses into the vaginal area.

  • Special Topic

    Uvea

    The cornea is the clear layer covering the front of the eye. The cornea works with the lens of the eye to focus images on the retina.

    The uvea is the middle layer of the eye beneath the white part of the eye (the ). It is made of the , , and . These structures control many eye functions, such as adjusting to different levels of light or different distances of objects. Inflammation of one or more of these structures is called ...

  • Disease

    Uveitis

    The eye is the organ of sight, a nearly spherical hollow globe filled with fluids (humors). The outer layer or tunic (sclera, or white, and cornea) is fibrous and protective. The middle tunic layer (choroid, ciliary body and the iris) is vascular. The innermost layer (the retina) is nervous or sensory. The fluids in the eye are divided by the lens into the vitreous humor (behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which allow it to change shape to focus light on the retina, which is composed of sensory neurons.

    Uveitis is swelling and irritation of the , the middle layer of the eye. The uvea provides most of the blood supply to the .

  • Disease

    Uvulitis

    The mouth is the origination of the digestive tract.  The teeth and salivary glands aid in breaking down food for digestion.  The tonsils aid against infections.

    Uvulitis is inflammation of the uvula, the small tongue-shaped piece of tissue that hangs from the top of the back part of the mouth. It is usually associated with inflammation of other mouth parts, such as the palate, tonsils, or throat (pharynx). See also: