Lipoamide dehydrogenase deficiency: A very rare enzyme deficiency (dihydrolipoamide dehydrogenase) which can cause lactic acidosis. The age of onset and symptoms are variable. More detailed information about the symptoms, causes, and treatments of Lipoamide dehydrogenase deficiency is available below.
Lipoatrophy with diabetes, hepatic steatosis, cardiomyopathy, and leukomelanodermic papules: A rare inherited disorder characterized by loss of fat under the skin, diabetes, heart muscle disease, fatty liver. More detailed information about the symptoms, causes, and treatments of Lipoatrophy with diabetes, hepatic steatosis, cardiomyopathy, and leukomelanodermic papules is available below.
Lipodermatosclerosis (medical condition): A rare condition that affects the skin above the ankles. It tends to occur in people with chronic vein problems which affects the blood flow the this area of skin. The skin becomes smooth, brown, tight and painful.
Lipodystrophy or lipoatrophy is primary idiopathic atrophy of adipose tissue. Lipodystrophy is a very rare disorder of unknown etiology.
A rare metabolic disorder involving abnormal fat gradually disappears from the limbs, trunk and buttocks but stays the same or accumulates on areas such as the face, shoulders, neck and genitals. More detailed information about the symptoms, causes, and treatments of Lipodystrophy, familial partial, type 3 (FPLD3) is available below.
Lipogranulomatosis (medical condition): A condition where abnormal lipid metabolism results in the development of yellow liquid-filled nodules in the skin and mucosal linings. The tissue surrounding the nodules can become inflamed as a result of these abnormal deposits. Symptoms are variable depending on the number and location of the nodules
Lipoid congenital adrenal hyperplasia: A rare form of congenital adrenal hyperplasia where the early phase of adrenal cortisol production is defective which causes mineralocorticoid deficiency. Male pseudohermaphroditism
Lipoid proteinosis of Urbach and Wiethe: A rare congenital lipoid storage disease where lipids, carbohydrates and proteins are deposited onto blood vessel walls and other tissues. More detailed information about the symptoms, causes, and treatments of Lipoid proteinosis of Urbach and Wiethe is available below
A rare disorder involving defective fat metabolism which leads to a buildup of fat deposits in neck and shoulder area. Mainly occurs in male alcoholics.
A rare slow-growing tumor that tends to occur mainly in deep in the thigh or in the retroperitoneum (space between the abdominal organs and the back of the abdominal space). Symptoms are determined by the size and location of the tumor. More detailed information about the symptoms, causes, and treatments of Lipomatous hemangiopericytoma is available below.
A lipomyelomeningocele (pronounced lipo-myelo-men-IN-go-seal) is a birth defect of a child’s spine. It is a fatty mass starting under the skin on the child’s back, usually in the middle. The mass extends inward to the spinal canal. It is covered in skin and is usually visible from outside the child’s body. The two biggest problems with lipomyelomeningocele in children are: 1. The spinal cord is stuck (fixed) to the fatty mass 2. The fatty mass puts pressure on the spinal cord
Abnormal lipoprotein use or processing by the body. The main repercussions of the disorder tends to be fatty deposits called xanthomas and premature heart disease. Examples of specific lipoprotein disorders includes type II hyperlipoproteinemia, hypoalphalipoproteinemia, hypertriglyceridemia and high lipoprotein a levels. Lipoprotein disorders can also result in harmfully low levels of lipoproteins which can cause symptoms such as failure to thrive and neuromuscular degeneration. Abetalipoproteinemia is an example of a lipoprotein disorder involving low blood lipoprotein levels. More detailed information about the symptoms, causes, and treatments of Lipoprotein disorder is available below.
Liposarcoma is a malignant tumor that arises in fat cells in deep soft tissue, such as that inside the thigh or in the retroperitoneum. Liposarcoma is a rare type of cancer that bears a resemblance to fat cells when examined under a microscope.
They are typically large bulky tumors, and tend to have multiple smaller satellites that extend beyond the main confines of the tumor.
Liposarcomas, like all sarcomas, are rare.
Lissencephaly (which literally means smooth brain,), is a rare brain formation disorder caused by defective neuronal migration during the 12th to 24th weeks of gestation resulting in a lack of development of brain folds (gyri) and grooves (sulci). It is a form of cephalic disorder. Terms such as 'agyria' (no gyri) or 'pachygyria' (broad gyri) are used to describe the appearance of the surface of the brain. Children with lissencephaly generally have significant developmental delays, but these vary greatly from child to child depending on the degree of brain malformation and seizure control. Life expectancy can be shortened, generally due to respiratory problems.
Lissencephaly - immunodeficiency: A very rare syndrome characterized mainly by abnormal brain development and a poor immune system. More detailed information about the symptoms, causes, and treatments of Lissencephaly - immunodeficiency is available below.
A very rare form of the brain formation disorder called lissencephaly where the brain surface is abnormally smooth rather than convoluted resulting in mental retardation. Physical malformations are also present. More detailed information about the symptoms, causes, and treatments of Lissencephaly syndrome type 1 is available below.
suggested this designation for a disorder which, like the Miller-Dieker syndrome (247200), is associated with type I lissencephaly but has distinctive associated features.
A rare brain malformation where the surface of the brain is smoother than normal. More detailed information about the symptoms, causes, and treatments of Lissencephaly, isolated is available below.
Listeriosis is an infection caused by the gram-positive motile bacterium Listeria monocytogenes. Listeriosis is relatively rare and occurs primarily in newborn infants, elderly patients, and patients who are immunocompromised.
Listeriosis is a bacterial infection most commonly caused by Listeria monocytogenes, although L. ivanovii and L. grayi have been reported in certain cases. Listeria primarily causes infections of the central nervous system (meningitis, meningoencephalitis, brain abscess, cerebritis) and bacteremia in those who are immunocompromised, pregnant women, and those at the extremes of age (newborns and the elderly), as well as gastroenteritis in healthy persons who have been severely infected. Listeria is ubiquitous and is primarily transmitted via the oral route after ingestion of contaminated food products, after which the organism penetrates the intestinal tract to cause systemic infections. The diagnosis of listeriosis requires the isolation of the organism from the blood and/or the cerebrospinal fluid. Treatment includes prolonged administration of antibiotics, primarily ampicillin and gentamicin, to which the organism is usually susceptible.
Logic syndrome (medical condition): A very rare syndrome characterized mainly by chronic skin ulceration, nail destruction, eye problems and mucosal nodules that can affect the voice and even impair breathing in severe cases.
Loa loa filariasis (also loiasis, Calabar swellings and African eyeworm) is a skin and eye disease caused by the nematode worm, loa loa filaria. Humans contract this disease through the bite of a horsefly. The Deer fly and the Mango fly are also vectors for Loa loa. The disease can cause red itchy swellings below the skin called "Calabar swellings". The disease is treated with the drug diethylcarbamazine (DEC).
A rare disorder involving severe loin pain, blood in the urine and kidney dysfunction is also frequent. More detailed information about the symptoms, causes, and treatments of Loin pain, hematuria syndrome is available below.
The long QT syndrome (LQTS) is a rare congenital heart condition with delayed repolarization following depolarization (excitation) of the heart, associated with syncope (fainting) due to ventricular arrhythmias, possibly of type torsade de pointes, which can deteriorate into ventricular fibrillation and ultimately sudden death. Arrhythmia in individuals with LQTS are often associated with exercise or excitement. Individuals with LQTS have a prolongation of the QT interval on the ECG. The Q wave on the ECG corresponds to ventricular depolarization while the T wave corresponds to ventricular repolarization. The QT interval is measured from the Q point to the end of the T wave. While many individuals with LQTS have persistent prolongation of the QT interval, some individuals do not always show the QT prolongation; in these individuals, the QT interval may prolong with the administration of certain medications.
The LQT2 type is the second most common gene location that is affected in long QT syndrome, making up about 25 to 30 percent of all cases. This form of long QT syndrome most likely involves mutations of the human ether-a-go-go related gene (HERG) on chromosome 7. The HERG gene (also known as KCNH2) is part of the rapid component of the potassium rectifying current (IKr). (The IKr current is mainly responsible for the termination of the cardiac action potential, and therefore the length of the QT interval.) The normally functioning HERG gene allows protection against early after depolarizations (EADs). Most drugs that cause long QT syndrome do so by blocking the IKr current via the HERG gene. These include erythromycin, terfenadine, and ketoconazole. The HERG channel is very sensitive to unintended drug binding due to two aromatic amino acids, the tyrosine at position 652 and the phenylalanine at position 656. These amino acid residues are poised so a drug binding to them will block the channel from conducting current. Other potassium channels do not have these residues in these positions and are therefore not as prone to blockage.
The LQT3 type of long QT syndrome involves mutation of the gene that encodes the alpha subunit of the Na+ ion channel. This gene is located on chromosome 3p21-24, and is known as SCN5A (also hH1 and NaV1.5). The mutations involved in LQT3 slow the inactivation of the Na+ channel, resulting in prolongation of the Na+ influx during depolarization. Paradoxically, the mutant sodium channels inactivate more quickly, and may open repetitively during the action potential. A large number of mutations have been characterized as leading to or predisposing LQT3. Calcium has been suggested as a regulator of SCN5A, and the effects of calcium on SCN5A may begin to explain the mechanism by which some these mutations cause LQT3. Furthermore mutations in SCN5A can cause Brugada syndrome, Cardiac Conduction disease and dilated cardiomyopathy. Rarely some affected individuals can have combinations of these diseases.
Loose anagen hair syndrome (loose anagen syndrome, loose anagen hair) is a non-inflammatory, non-scarring form of hair loss. It is a condition that has been defined very recently and it generally affects the children. As the name suggests, loose anagen syndrome means growth of hair that is “loose” and easily pulled out of the hair follicle.
Lopes Gorlin syndrome is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Lopes Gorlin syndrome, or a subtype of Lopes Gorlin syndrome, affects less than 200,000 people in the US population.
A very rare syndrome characterized mainly by decreased hair and mental retardation. More detailed information about the symptoms, causes, and treatments of Lopes-Marques de Faria syndrome is available below.