Atransferrinemia
Atransferrinemia (also called congenital hypotransferrinemia) is a very rare inherited blood disorder where the body makes little or no transferrin, the main protein that carries iron in the blood. ...
Rx Blood, Metabolism, and Infectious Diseases (A – Z)
Atelosteogenesis Type III (AO3)
Atelosteogenesis type III (AO3) is a very rare genetic condition that affects how bones form before birth. Babies are usually born with very short arms and legs, joints that can dislocate (hips, ...
Atelosteogenesis Type I
Atelosteogenesis type I is a very rare genetic condition that affects how bones form before birth. Babies have very short arms and legs, dislocated large joints (hips, knees, elbows), clubfeet, and ...
Astley-Kendall Dysplasia
Astley-Kendall dysplasia is a lethal skeletal dysplasia. “Lethal” here means most affected babies die before birth or in the newborn period. It is marked by very short arms and legs, fragile bones ...
Aspergillus Niger Infection
Aspergillus niger infection means illness in a person caused by the fungus Aspergillus niger. A. niger is a “black mold” that lives widely in the environment—in soil, plants, air, and dust. Most ...
Aromatic L-amino Acid Decarboxylase (AADC) Deficiency
Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare, inherited brain chemistry disorder. The body cannot properly make the “monoamine” messenger chemicals that carry signals between nerve ...
Aromatase Deficiency (CYP19A1-Related Estrogen Biosynthesis Disorder)
Aromatase deficiency is a very rare, inherited condition caused by changes (mutations) in the CYP19A1 gene. The gene makes the enzyme aromatase, which converts androgens (like testosterone) into ...
Argininosuccinic Acid Lyase Deficiency
Argininosuccinic acid lyase deficiency (also called argininosuccinic aciduria) is a rare, inherited disorder of the urea cycle, the body’s pathway for clearing extra nitrogen by turning it into urea ...
Argininosuccinate Lyase (ASL) Deficiency
ASL deficiency is a rare inherited condition of the urea cycle—the body’s “nitrogen disposal” system. In healthy people, the urea cycle turns toxic ammonia (made when we break down protein) into ...
Argininosuccinase Deficiency
Argininosuccinase deficiency (also called argininosuccinic aciduria, ASA) is a rare, inherited urea-cycle disorder. The urea cycle is the body’s main way to turn toxic ammonia (made when we break ...
Argininosuccinic Aciduria (ASL Deficiency)
Argininosuccinic aciduria is a rare, inherited metabolic disorder that makes it hard for the body to clear ammonia—the waste product that forms when we break down protein. Ammonia is toxic, ...
Argentine Hemorrhagic Fever (AHF)
Argentine hemorrhagic fever (AHF) is a serious viral illness caused by the Junín virus (a New World arenavirus). People usually get it after contact with infected field rodents in parts of Argentina. ...
Apparent Mineralocorticoid Excess
Apparent mineralocorticoid excess is a rare condition where the body acts as if it has too much aldosterone (the salt-retaining hormone), even though aldosterone is low. The problem is not the ...
Hughes Syndrome
Hughes syndrome—also called antiphospholipid syndrome (APS)—is an autoimmune condition in which the body makes antibodies that mistakenly target proteins bound to phospholipids on cells. These ...
Anti Neutrophil Cytoplasmic Antibody Associated Vasculitis (AAV)
Anti-neutrophil cytoplasmic antibody-associated vasculitis—shortened to AAV—is a group of rare autoimmune diseases where a person’s immune system makes antibodies (called ANCAs) that mistakenly ...
Anti-HLA Hyperimmunization
Anti-HLA hyperimmunization means a person’s immune system has made very high levels of antibodies against other people’s HLA proteins (human leukocyte antigens). HLA proteins sit on cells and help ...
Angiostrongyliasis (Rat Lungworm Disease)
Angiostrongyliasis is an infection by roundworms in the genus Angiostrongylus. The most common human illness is caused by A. cantonensis (often called rat lungworm) and mainly affects the brain and ...
Haemangiectatic Hypertrophy
Haemangiectatic hypertrophy is an old umbrella term doctors used for limb or body-part overgrowth caused by congenital (present at birth) vascular malformations. Today, the best-known modern name for ...
X-linked Dominant Severe Hemolytic Anemia due to G6PD Deficiency
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic problem in red blood cells. The G6PD enzyme helps red cells make NADPH, which protects them from “oxidative” damage. When the enzyme ...
Hemolytic Anemia Due to G6PD Deficiency
Hemolytic anemia due to G6PD deficiency happens when red blood cells (RBCs) break down faster than the body can replace them because they lack enough of an enzyme called glucose-6-phosphate ...
