DEFINITION Vasovagal syncope (vay-zoh-VAY-gul SING-kuh-pee) is one of the most common causes of fainting. Vasovagal syncope occurs when your body overreacts to certain triggers, such as the sight of blood or extreme emotional distress. The vasovagal syncope trigger causes a…
DEFINITION Vitiligo (vit-ih-LIE-go) is a disease that causes the loss of skin color in blotches. The extent and rate of color loss from vitiligo is unpredictable. It can affect the skin on any part of your body. It may also…
DEFINITION Vitamin deficiency anemia is a lack of healthy red blood cells caused by lower than normal amounts of certain vitamins. Vitamins linked to vitamin deficiency anemia include folate, vitamin B-12 and vitamin C. Vitamin deficiency anemia can occur if…
DEFINITION Viral hemorrhagic (hem-uh-RAJ-ik) fevers are infectious diseases that interfere with the blood’s ability to clot. These diseases can also damage the walls of tiny blood vessels, making them leaky. The internal bleeding that results can range from relatively minor…
DEFINITION Vesicoureteral (ves-ih-koe-yoo-REE-tur-ul) reflux is the abnormal flow of urine from your bladder back up the tubes (ureters) that connect your kidneys to your bladder. Normally, urine flows only down from your kidneys to your bladder. Vesicoureteral reflux is usually…
DEFINITION A spinal tumor is a growth that develops within your spinal canal or within the bones of your spine. It may be cancerous or noncancerous. Tumors that affect the bones or vertebrae of the spine are called vertebral tumors.…
DEFINITION Ventricular tachycardia is a type of heart rhythm disorder (arrhythmia) in which the lower chambers of your heart (ventricles) beat very quickly because of a problem in your heart’s electrical system. In ventricular tachycardia, your heart may not be…
DEFINITION A ventricular septal defect (VSD), a hole in the heart, is a common heart defect that’s present at birth (congenital). The hole occurs in the wall that separates the heart’s lower chambers (septum) and allows blood to pass from…
DEFINITION Ventricular fibrillation is a heart rhythm problem that occurs when the heart beats with rapid, erratic electrical impulses. This causes pumping chambers in your heart (the ventricles) to quiver uselessly, instead of pumping blood. Sometimes triggered by a heart…
DEFINITION Vocal cord paralysis occurs when the nerve impulses to your voice box (larynx) are disrupted. This results in paralysis of the vocal cord muscles. Vocal cord paralysis can affect your ability to speak and even breathe. That’s because your…
DEFINITION Type 2 diabetes in children is a chronic condition that affects the way your child’s body metabolizes sugar (glucose). Type 2 diabetes is a disease more commonly associated with adults. In fact, it used to be called adult-onset diabetes.…
DEFINITION Type 2 diabetes, once known as adult-onset or noninsulin-dependent diabetes, is a chronic condition that affects the way your body metabolizes sugar (glucose), your body’s important source of fuel. With type 2 diabetes, your body either resists the effects…