Diseases

Lamellar ichthyosis

Lamellar ichthyosis, also known as ichthyosis lamellaris and nonbullous congenital ichthyosis, is a rare inherited skin disorder, affecting around 1 in 600,000 people.

Lamellar ichthyosis- autosomal dominant form

Lamellar ichthyosis, autosomal dominant form: A very rare dominantly inherited disorder where an infant is born covered with a transparent membrane which sheds to reveal red scaly skin patches of varying sizes.

Lamellar ichthyosis- type 2

A very rare disorder where an infant is born covered with a transparent membrane which sheds to reveal red scaly skin patches of varying sizes. Type 2 is distinguished by the location of the genetic defect - chromosome 2q34

Lamellar ichthyosis- type 3

A very rare disorder where an infant is born covered with a transparent membrane which sheds to reveal large dark, plate-like scales. Type 3 is distinguished by the location of the genetic defect - chromosome 19p12-q12. This type also affects the ears and face to a greater degree than other types.

Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is a childhood disorder. A major feature of LKS is the gradual or sudden loss of the ability to understand and use spoken language. All children with LKS have abnormal electrical brain waves that can be documented by an electroencephalogram (EEG), a recording of the electric activity of the brain. Approximately 80 percent of the children with LKS have one or more epileptic seizures that usually occur at night. Behavioral disorders such as hyperactivity, aggressiveness and depression can also accompany this disorder. LKS may also be called infantile acquired aphasia, acquired epileptic aphasia or aphasia with convulsive disorder. This syndrome was first described in 1957 by Dr. William M. Landau and Dr. Frank R. Kleffner, who identified six children with the disorder.

Landouzy-Dejerine muscular dystrophy

A rare inherited neuromuscular disorder characterized mainly by progressive weakness and wasting of facial and shoulder and upper arm muscles. A rare form of the condition is noticeable at infancy and progresses rapidly.

Landy Donnai syndrome

A very rare disorder characterized by a missing fingers and hand bones, webbed fingers, duplicated big toe and hydrops.

Langer Nishino Yamaguchi syndrome

A rare disorder characterized by deformed forearms and lower legs, cloudy corneas and enlarged kidneys. In the reported case, death occurred in the newborn period from kidney and heart failure.

Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a rare disease involving clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes. Clinically, its manifestations range from isolated bone lesions to multisystem disease. LCH is part of a group of clinical syndromes called histiocytoses, which are characterized by an abnormal proliferation of histiocytes (an archaic term for activated dendritic cells and macrophages). These diseases are related to other forms of abnormal proliferation of white blood cells, such as leukemias and lymphomas.

The disease has gone by several names, including Hand–Schüller–Christian disease, Abt-Letterer-Siwe disease, and histiocytosis X, until it was renamed in 1985 by the Histiocyte Society.

Laparoschisis

A rare birth disorder involving a defect in the abdominal wall through which some of the abdominal contents may protrude. The defect occurs near the umbilical cord.

Laron syndrome

Laron syndrome is a condition that occurs when the body is unable to utilize growth hormone. It is primarily characterized by short stature.  It is often caused by mutations in the GHR gene and is inherited in an autosomal recessive manner. Treatment is focused on improving growth and generally includes injections of insulin-like growth factor 1 (IGF-1).

Type 1 involves a defect in the growth hormone receptor gene which prevents the hormone from binding and being used. Hence there are high levels of free growth hormone in the plasma. Type 2 involves a problem with the processing of the growth hormone once it has been bound properly to the cell surface.

Laron-type dwarfism

A rare genetic disease where the body has sufficient growth hormones but lacks receptors to utilize the hormone and hence dwarfism results.

Larsen like syndrome- lethal type

A very rare lethal syndrome characterized mainly by joint dislocations and breathing problems due to respiratory system abnormalities.

Larsen syndrome

Larsen syndrome (LS), is a congenital disorder discovered in 1950 by Larsen and associates when they observed dislocation of the large joints and face anomalies in six of their patients. Patients suffering from Larsen syndrome normally present with a variety of symptoms including: congenital anterior dislocation of the knees, dislocation of the hips and elbows, flattened facial appearance, prominent foreheads, and depressed nasal bridges. Larsen syndrome can also cause a variety of cardiovascular anomalies and orthopedic abnormalities. This rare disorder is caused by a genetic defect in the gene encoding filamin B, a cytoplasmic protein that is important in regulating the structure and activity of the cytoskeleton. The gene that influences the emergence of Larsen syndrome is found in chromosome region, 3p21.1-14.1, a region containing Human type VII collagen gene. Larsen syndrome has recently been described as a mesenchyme disorder that affects the connective tissue of an individual. Autosomal dominant and recessive forms of the disorder have been reported, although most cases are autosomal dominant. Reports have found that in Western societies, Larsen syndrome can be found in 1 in every 100,000 births, however, this is most likely an underestimate because the disorder is frequently unrecognized or diagnosed as another disorder.

Larsen syndrome- dominant type

A congenital, genetic disorder characterized by many abnormalities including joint dislocations, bone abnormalities and an unusual dish-shaped face. The dominant form tends to have less severe dwarfism and more severe flattening of the face and is less likely to include webbed fingers, cleft palate and genital anomalies than the recessive form.

Larsen syndrome- recessive type

A congenital, genetic disorder characterized by many abnormalities including joint dislocations, bone abnormalities and an unusual face.

Laryngeal carcinoma

Laryngeal cancer may also be called cancer of the larynx or laryngeal carcinoma. Most laryngeal cancers are squamous cell carcinomas, reflecting their origin from the squamous cells which form the majority of the laryngeal epithelium. Cancer can develop in any part of the larynx, but the cure rate is affected by the location of the tumor. For the purposes of tumour staging, the larynx is divided into three anatomical regions: the glottis (true vocal cords, anterior and posterior commissures); the supraglottis (epiglottis, arytenoids and aryepiglottic folds, and false cords); and the subglottis.

Laryngeal cleft

Laryngeal cleft is a rare abnormality of the separation between the larynx, or voice box, and the esophagus. When the larynx develops normally it is completely separate from the espophagus, so swallowed foods go directly into the stomach. A laryngeal cleft creates an opening between the larynx and the esophagus so food and liquid can pass through the larynx into the lungs.

Laryngeal papillomatosis

Laryngeal papillomatosis is a form of recurrent respiratory papillomatosis where tumors (papillomas) grow in the larynx (voice box). These tumors can recur frequently, may require repetitive surgery, and may interfere with breathing. The disease can be treated with surgery and antivirals.

Laryngocele

A rare condition where an air-filled sac associated with the larynx becomes dilated.

Laryngomalacia

A defect where the larynx is abnormally soft which affects voice quality and can cause breathing problems. The larynx is so soft that when inhalation occurs, the larynx collapses and obstructs the breathing passage.

Laryngomalacia dominant congenital

A dominantly inherited birth defect where the larynx is abnormally soft which affects voice quality and can cause breathing problems. The larynx is so soft that when inhalation occurs, the larynx collapses and obstructs the breathing passage.