Transposition of the great arteries (or vessels) is a rare issue where the main arteries that move blood out of your heart are in the wrong places. They also connect to your heart in the wrong places. It’s a congenital (present at birth) condition. The two reversed (transposed) arteries are: The main pulmonary artery, which carries blood into your lungs. The aorta, the artery that carries blood from your heart to …

Toxoplasmosis is an illness caused by an infection with the parasite Toxoplasma gondii (T. gondii). The parasite reproduces in the intestinal tracts of cats. Humans become infected by direct or indirect contact with cat poop (feces) or by eating undercooked meat. Most people don’t have symptoms when they get infected. But as your immune system attacks the parasite, it creates cysts in your body. …

Toxic shock syndrome (TSS) is a rare but potentially life-threatening condition caused by certain strains of bacteria that produce poisons (toxins). These toxins get into your bloodstream and can affect organs such as your heart, liver or kidneys. It’s often associated with using tampons during menstruation. However, TSS can affect anyone of any age. Skin wounds, surgical incisions, nasal packing, scrapes, …

Tourette syndrome (TS) is a neurological disorder that affects the brain and nerves. TS causes a person to make sudden movements or sounds called “tics.” Tics are involuntary, so you can’t control or prevent them. Motor tics involve body movements, like shoulder shrugging. Vocal tics involve the voice, like throat clearing. Motor tics tend to develop before vocal tics. Tourette syndrome, or …

A torn meniscus is a tear in the tough cartilage inside your knee. Two pieces of cartilage sit inside your knee between your thighbone (femur) and shinbone (tibia). This cartilage is the meniscus. The rubbery wedges of cartilage act like shock absorbers for your knee, providing cushioning for your bones and knee joint. It can tear after a hard twist or rotation …

A tooth abscess is a pocket of pus from a bacterial infection in your gums. An abscess usually looks like a red, swollen bump, boil or pimple. It affects the involved tooth, but the infection can also spread to surrounding bone and neighboring teeth. Abscesses can occur in different places around a tooth for different reasons. Three types of tooth infections can cause abscesses: …

Tonsillitis occurs when your tonsils become infected. Tonsils are the two small lumps of soft tissue — one on either side — at the back of your throat. You can see your tonsils in a mirror by opening your mouth and sticking out your tongue. Your tonsils are part of your immune system, and they help trap germs that make you sick. When your …

Tonsil cancer is a cancerous tumor on your tonsils, which are in the back of your throat (pharynx). Tonsil cancer is the most common form of oropharyngeal cancer. A sore throat that doesn’t go away is a common early symptom. Often, healthcare providers can successfully treat tonsil cancer if they detect it before it spreads. How common is tonsil cancer? It’s not common. The …

A tonic-clonic seizure is a type of seizure that causes strong muscle movements on both sides of your body, including convulsions. These are typically the best known and easiest to recognize seizures because of these movements. Tonic-clonic seizures were formerly known as “grand mal” seizures, from the French phrase meaning “great illness.” The term “tonic-clonic” refers to the two phases of these …

Tongue-tie is when a baby’s tongue can’t move as well as it should because a fold of tissue connects the bottom of their tongue to the floor of their mouth. This fold of tissue, called the lingual frenulum, is present in all children and usually harmless. But sometimes, a lingual frenulum that’s too tight or short can restrict the movement and function …