Facial-digital-genital syndrome Causes: Aarskog syndrome is a genetic disorder that is linked to the X chromosome. It affects mainly males, but females may have a milder form. The condition is caused by changes (mutations) in a gene called "faciogenital dysplasia" ( FGD1 ).
Aase-Smith syndrome; Hypoplastic anemia/Triphalangeal thumb syndrome Causes: Most cases of Aase syndrome occur without a known reason and are not passed down through families (inherited). However, some cases have been shown to be inherited. This condition is similar to Diamond-Blackfan anemia, and the two conditions should not be separated.
Aneurysm - aortic; AAA Causes: The exact cause of the condition is unknown. Factors that can increase your risk of developing the problem include: Smoking High blood pressure Male gender Genetic factors An abdominal aortic aneurysm is most often seen in males over age 60 who have one or more risk factors.
A, B, AB, and O are the four major blood types. The types are based on small substances (molecules) on the surface of the blood cells. When people who have one blood type receive blood from someone with a different blood type, it may cause their immune system to react. This is called ABO incompatibility. Causes: The different blood types are: Type A Type B Type AB Type O People who have one blood type may form proteins (antibodies) that cause their immune system to react against one or more of the other blood types.
An abscess is a collection of pus in any part of the body that, in most cases, causes swelling and inflammation around it. Causes: Abscesses occur when an area of tissue becomes infected and the body's immune system tries to fight it. White blood cells move through the walls of the blood vessels into the area of the infection and collect in the damaged tissue. During this process, pus forms. Pus is the buildup of fluid, living and dead white blood cells, dead tissue, and bacteria or other foreign substances.
Abscess - intra-abdominal; Pelvic abscess Causes: You can get abdominal abscesses because you have: A burst appendix A burst intestine A burst ovary Inflammatory bowel disease Infection in your gallbladder, pancreas, ovary or other organs Pelvic infection Parasite infection You are more at risk for an abdominal abscess if you have: Trauma Perforated ulcer disease Surgery in your belly area Weakened immune system Germs may pass through your blood to an organ in your belly.
Seizure - petit mal; Seizure - absence; Petit mal seizure; Epilepsy - absence seizure Causes: Absence seizures occur most often in people under age 20, usually in children ages 6 to 12. In some cases, the seizures are triggered by flashing lights or when the person breathes faster and more deeply than usual (hyperventilates).
Absent pulmonary valve syndrome; Congenital absence of the pulmonary valve; Pulmonary valve agenesis Causes: Absent pulmonary valve occurs when the pulmonary valve does not form or develop properly while the baby is in the mother's womb.
Acanthosis nigricans is a skin disorder in which there is darker, thick, velvety skin in body folds and creases. Causes: Acanthosis nigricans can affect otherwise healthy people, or it can be related to medical problems. Some cases are genetically inherited. The condition is most commonly seen among people of African descent, in part because it is easier to see in darker skin. Obesity can lead to acanthosis nigricans, as can some endocrine disorders. It is often found in people with obesity-related insulin resistance.
Esophageal achalasia Causes: There is a muscular ring at the point where the esophagus and stomach meet, called the lower esophageal sphincter. Normally, this muscle relaxes when you swallow. In people with achalasia, it does not relax as well. In addition, the normal muscle activity of the esophagus (peristalsis) is reduced.