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All Communities

  • LADD Syndrome

    1 members

    LADD Syndrome is a rare genetic disorder characterized by abnormalities affecting the lacrimal and salivary glands and ducts, ears, teeth and fingers and toes.

  • Lafora Disease

    1 members

    Lafora Disease is a rare genetic disorder characterized by the presence of Lafora bodies, within neurons and the cells of the heart, liver, muscle, and skin.

  • Lambert-Eaton Myasthenic Syndrome

    8 members

    Lambert-Eaton Myasthenic Syndrome is a rare autoimmune disorder which affects calcium delivery to the nerve-muscle junctions.

  • Lamellar Ichthyosis

    4 members

    Lamellar Ichthyosis is a rare inherited skin disorder.

  • Landau-Kleffner Syndrome

    4 members

    Landau-Kleffner Syndrome is a childhood disorder characterized by the loss of the ability to understand and use spoken language.

  • Langerhans Cell Histiocytosis

    12 members

    Langerhans Cell Histiocytosis (LCH) is a rare disorder involving the langerhans cells, typically found bone marrow, which migrate throughout the body.

  • Large Congenital Melanocytic Nevus

    5 members

    A Large or Giant Congenital Melanocytic Nevus (plural: Nevi) is a pigmented lesion, substantial in size, either present at birth or very shortly after birth (within 2 years). These rare large birt...

  • Large Granular Lymphocytic Leukemia

    252 members

    Large granular lymphocyte leukemia or LGLL is a rare cancer of a type of white blood cells called lymphocytes. Lymphocytes are part of the immune system, the natural defense of the body that hel...

  • Larsen Syndrome


  • Laryngo-Tracheo-Esophageal Cleft

    1 members

  • Lateral body wall complex

    1 members

  • Lateral Medullary Syndrome

    1 members

    Lateral Medullary Syndrome is a rare disorder characterized by difficulty swallowing or speaking due to dead tissue.



  • Lateral Meningocele Syndrome

    4 members

    Lateral Meningocele Syndrome is a rare disorder characterized by multiple lateral meningoceles (meninges protrude from a spinal opening).

  • Leber Hereditary Optic Neuropathy

    9 members

    Leber Hereditary Optic Neuropathy is an inherited degeneration of retinal ganglion cells leading to loss of central vision.

  • Leber's Congenital Amaurosis

    4 members

    Leber's Congenital Amaurosis is a rare inherited eye disorder.

  • Ledderhose's Disease

    16 members

    Ledderhose's Disease is a rare disorder consisting of non-malignant thickening of the feet's deep connective tissue.

  • Legg-Calve-Perthes Syndrome

    7 members

    Legg-Calve-Perthes Syndrome is a degenerative disease of the hip joint.

  • Leigh Syndrome

    8 members

    Leigh Syndrome is a rare genetic disorder caused by mutations in mitochondrial DNA or by deficiencies of an enzyme called pyruvate dehydrogenase.

  • Leiomyosarcoma

    7 members

    Leiomyosarcoma is a rare form of cancer arising from muscle tissue.

  • Lemierre's Syndrome

    4 members

    Lemierre's Syndrome is a rare disorder characterized by oropharyngeal infection, usually caused by Fusobacterium necrophorum.

  • Lennox-Gastaut Syndrome

    7 members

    Lennox–Gastaut Syndrome is a rare form of childhood-onset epilepsy.

  • Léri-Weill Dyschondrosteosis

    9 members

    Léri-Weill Dyschondrosteosis is a rare disorder which results in dwarfism.

  • Lesch-Nyhan Syndrome

    2 members

  • Lewis-Sumner Syndrome

    9 members

    Lewis-Sumner Syndrome is a dysimmune multifocal demyelinating sensorimotor neuropathy.

  • Leydig Cell Tumor


    Leydig cell tumors are rare tumors of the testis derived from the interstitial cells.

  • Lichen Sclerosus

    13 members

    Lichen Sclerosus is a rare disorder characterized by white patches on the skin.

  • Light Chain Deposition Disease

    17 members

    Light Chain Deposition Disease is a rare disorder in which the monoclonal sFLC accumulates within cells in the kidneys and other organs.

  • Limb-Girdle Muscular Dystrophy

    3 members

  • Linear Morphea

    3 members

    Linear Morphea is a variant of localized scleroderma usually occurring along the length of a limb or around the trunk.

  • Lipodermatosclerosis

    11 members

    Lipodermatosclerosis is a rare skin disorder characterized by smooth, brown, tight and painful skin just above the ankle resulting in chronic venous insufficiency.

  • Lipodystrophy

    17 members

    Lipodystrophy is a disorder characterized by loss of body fat in particular areas of the body.

  • Loin Pain Hematuria Syndrome

    12 members

    Loin Pain Hematuria Syndrome is the combination of flank pain and blood in the urine that is otherwise unexplained.

  • Long Chain 3-Hydroxyacyl-CoA Dehydrogenase

    3 members

    Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency is a rare disorder that prevents the body from converting certain fats to energy.

  • Long QT Syndrome


  • Loose Anagen Hair Syndrome

    6 members

    Loose Anagen Hair Syndrome is a rare disorder in which hair falls out easily and is pulled out easily.

  • Lowe Syndrome


    Lowe Syndrome is a rare genetic disorder characterized by hydrophthalmia, cataracts, intellectual disabilities, aminoaciduria, reduced renal ammonia production and vitamin D-resistant rickets.

  • Lujan-Fryns Syndrome

    3 members

    Lujan-Fryns syndrome is a rare genetic disorder which causes mental retardation and physical characteristics similar to those found in Marfan syndrome.

  • Lymphangioleiomyomatosis

    6 members

    Lymphangioleiomyomatosis is a rare idiopathic disorder.

  • Lymphangiomatosis

    4 members

    Lymphangiomatosis is a rare condition where a lymphangioma is present in a widespread or multifocal manner.

  • Lymphocytic Colitis

    4 members

    Lymphocytic Colitis is a rare disorder characterized by diarrhea.

  • Lymphomatoid Papulosis

    5 members

    Lymphomatoid Papulosis is a rare skin disorder suggestive of malignant lymphoma.