Diseases

Atrial septal defect

Atrial septal defects (ASDs) are a group of rare disorders of the heart that are present at birth (congenital) and involve a hole in the wall (septum) that separates the two upper-chambers (atria) of the heart. Small atrial septal defects may close on their own during infancy or early childhood.

Normally the heart has four chambers: two upper chambers known as atria that are separated from each other by a fibrous partition known as the atrial septum and two lower chambers known as ventricles that are separated from each other by the ventricular septum. Valves connect the atria (left and right) to their respective ventricles. A small opening between the two atria (foramen ovale) is present at birth. Shortly after birth, the atrial septum gradually grows and seals this opening. In infants with atrial septal defects, the atrial septum may not close properly or may be malformed during fetal development. In these disorders, the opening (called patent foramen ovale) between the atria persists long after it should be closed, resulting in an increase in the workload on the right side of the heart and excessive blood flow to the lungs.

Initially, the symptoms associated with atrial septal defects may be absent or so mild that they may go unnoticed. Frequently this disorder is not recognized until school age or even adulthood. In adults with undetected atrial septal defects, various respiratory problems and/or heart failure may develop. An adult who has had an undetected atrial septal defect for decades may have a shortened life span from heart failure or high blood pressure that affects the arteries in the lungs (pulmonary hypertension). Surgery may be necessary to repair atrial septal defects to prevent complications.

Several forms of atrial septal defects are recognized. They are classified according to their location in the septum. The term primum refers to defects that are in the lower part of the septum. The term secundum refers to defects that are located in the middle of the septum, and the term sinus venosus refers to defects in the upper part of the septum.

Subdivisions of Atrial Septal Defects:

  • Ostium Primum Defect (endocardial cushion defects included)
  • Ostium Secundum Defect
  • Sinus Venosus
  • Coronary sinus

Ostium Primum Defect:

Ostium primum atrial septal defect is less common. The lower part of the atrial septum fails to develop normally, leaving an opening between the atria. Frequently, the valves that separate the atria from their respective ventricles (tricuspid and mitral) are also malformed, and the septum that divides the ventricles may also be deficient or malformed (atrioventricular septal defect). Another defect may have occurred during embryonic development in the tissue that forms the septum that divides the heart into atria and ventricles (endocardial cushion defect).

Ostium Secundum Defect:

Ostium secundum atrial septal defect is the most common form of this group of heart defects. The middle portion of the atrial septum in the region of the foramen ovale fails to close during fetal development. The size of the opening may vary, along with the severity of the symptoms.

Sinus Venosus:

Sinus venosus, the least common form of atrial septal defect, occurs when there is an opening on the upper portion of the atrial septum. This defect is often associated with malformations of the vein that leads from the lungs into the heart (right pulmonary vein). One of the major veins of the body that returns blood to the heart (superior vena cava) may also be malformed.

Coronary sinus:

In this rare defect, part of the wall between the coronary sinus — which is part of the vein system of the heart — and the left atrium is missing.

Atrioventricular septal defect

Atrioventricular canal defect is a combination of heart problems resulting in a defect in the center of the heart. The condition occurs when there's a hole between the heart's chambers and problems with the valves that regulate blood flow in the heart. The condition is often associated with Down syndrome.

Atrioventricular canal defect allows extra blood to flow to the lungs. The extra blood forces the heart to overwork, causing the heart muscle to enlarge.

Untreated, atrioventricular canal defect can cause heart failure and high blood pressure in the lungs. Doctors generally recommend surgery during the first year of life to close the hole in the heart and to reconstruct the valves

Atrophoderma of Pierini and Pasini

Atrophoderma of Pierini and Pasini is thought to possibly represent a late stage of morphea a type of localized scleroderma. It is a progressive skin disease characterized by violet or brown skin lesions of varying sizes. The disease results in round or oval patches of hyper-pigmented skin. The darkened skin patches may sometimes have a bluish or purplish hue when they first appear and are often smooth to the touch and hairless. It is characterized by large lesions with a sharp peripheral border dropping into a depression with no outpouching, which, on biopsy, elastin is normal, while collagen may be thickened.

Atrophodermia vermiculata

Atrophodermia vermiculata presents with erythematous follicular papules on the cheeks in childhood, and, with time, the lesions develop into pit-like depressions. Symmetrical vermiform facial atrophy usually beginning between the ages of 5 and 12. Erythema and pinhead follicular plugs developing mainly on the cheeks are soon followed by asymptomatic, sharply demarcated, pit-like or net-like impressions. 

Attenuated familial adenomatous polyposis

Attenuated familial adenomatous polyposis is a rare, inherited condition that causes extra tissue (polyps) to form in your large intestine (colon) and rectum. Polyps can also occur in the upper gastrointestinal tract, especially the upper part of your small intestine (duodenum). People with the classic type of familial adenomatous polyposis may begin to develop multiple noncancerous (benign) growths (polyps) in the colon as early as their teenage years. Unless the colon is removed, these polyps will become malignant (cancerous). The average age at which an individual develops colon cancer in classic familial adenomatous polyposis is 39 years. Some people have a variant of the disorder, called attenuated familial adenomatous polyposis, in which polyp growth is delayed. The average age of colorectal cancer onset for attenuated familial adenomatous polyposis is 55 years.

In people with classic familial adenomatous polyposis, the number of polyps increases with age, and hundreds to thousands of polyps can develop in the colon. Also of particular significance are noncancerous growths called desmoid tumors. These fibrous tumors usually occur in the tissue covering the intestines and may be provoked by surgery to remove the colon. Desmoid tumors tend to recur after they are surgically removed. In both classic familial adenomatous polyposis and its attenuated variant, benign and malignant tumors are sometimes found in other places in the body, including the duodenum (a section of the small intestine), stomach, bones, skin, and other tissues. People who have colon polyps as well as growths outside the colon are sometimes described as having Gardner syndrome.

A milder type of familial adenomatous polyposis, called autosomal recessive familial adenomatous polyposis, has also been identified. People with the autosomal recessive type of this disorder have fewer polyps than those with the classic type. Fewer than 100 polyps typically develop, rather than hundreds or thousands. The autosomal recessive type of this disorder is caused by mutations in a different gene than the classic and attenuated types of familial adenomatous polyposis.

Most people with familial adenomatous polyposis eventually need surgery to remove the large intestine to prevent cancer. The polyps in the duodenum also can develop cancer, but they can usually be managed by careful monitoring and removing polyps regularly.

Atypical hemolytic uremic syndrome

Atypical hemolytic-uremic syndrome (aHUS) is a disease that causes abnormal blood clots to form in small blood vessels in the kidneys. These clots can cause serious medical problems if they restrict or block blood flow, including hemolytic anemia, thrombocytopenia, and kidney failure. It can occur at any age and is often caused by a combination of environmental and genetic factors. Genetic factors involve genes that code for proteins that help control the complement system (part of your body’s immune system). Environmental factors include certain medications (such as anticancer drugs), chronic diseases (e.g., systemic sclerosis and malignant hypertension), viral or bacterial infections, cancers, organ transplantation, and pregnancy.  Most cases are sporadic. Less than 20 percent of all cases have been reported to run in families. When the disorder is familial, it can have an autosomal dominant or an autosomal recessive pattern of inheritance.

Atypical hemolytic-uremic syndrome should be distinguished from a more common condition called typical hemolytic-uremic syndrome. The two disorders have different causes and different signs and symptoms. Unlike the atypical form, the typical form is caused by infection with certain strains of Escherichia coli bacteria that produce toxic substances called Shiga-like toxins. The typical form is characterized by severe diarrhea and most often affects children younger than 10. The typical form is less likely than the atypical form to involve recurrent attacks of kidney damage that lead to ESRD. 

Atypical lipodystrophy

A rare disorder involving the localized loss of fatty tissue. More than one location may be involved. The condition is mainly associated with injections or acupuncture.

Atypical mole syndrome

Atypical mole syndrome, also called dysplastic nevus syndrome, is a disorder of the skin characterized by the presence of many mole-like tumors (nevi). Most people have 10-20 moles over their bodies. People with this syndrome often have more than 100 mole.

Atypical mycobacteriosis- familial

A very rare group of disorders where a person without an immune deficiency is susceptible to infection by weak mycobacterial organisms, nontuberculous and environmental mycobacteria e.g. Calmette-Guerin Bacillus (BCG). The severity of the disorder is greatly variable and ranges from a localized recurring non-tuberculous mycobacterial infection to a potentially fatal BCG infection. Most people who are infected with these organisms have no symptoms but a genetic mutation in some people makes them more susceptible.

Auditory neuropathy

Auditory neuropathy is a rare condition that can affect a person's ability to hear. Although sounds enter the inner ear normally, signals from the inner ear to the brain are not transmitted properly. As a result, the condition may be associated with mild to severe hearing loss and poor speech-perception abilities (difficulty understanding speech clearly). Auditory neuropathy can be associated with other neurological disorders such as Friedrich ataxia,Stevens-Johnson syndrome, Ehlers-Danlos syndrome, and Charcot-Marie-Tooth syndrome.

Auditory perceptual disorder

It is an umbrella term for a variety of disorders that affect the way the brain processes auditory information. Individuals with this disease usually have normal structure and function of the outer, middle and inner ear (peripheral hearing). However, they cannot process the information they hear in the same way as others do, which leads to difficulties in recognizing and interpreting sounds, especially the sounds composing speech. It is thought that these difficulties arise from dysfunction in the central nervous system.

Aughton syndrome

A very rare syndrome characterized primarily by small eyes, cleft palate, mental retardation and dextrocardia (heart located on right side of chest instead of left).

Auralcephalosyndactyly

A very rare syndrome characterized by ear abnormalities, premature fusion of skull bones and syndactyly (fusion of digits).

Auriculo-condylar syndrome

Auriculo-condylar syndrome is a condition that affects facial development, particularly development of the ears and lower jaw (mandible).
Most people with auriculo-condylar syndrome have malformed outer ears ("auriculo-" refers to the ears). A hallmark of this condition is an ear abnormality called a "question-mark ear," in which the ears have a distinctive question-mark shape caused by a split that separates the upper part of the ear from the earlobe. Other ear abnormalities that can occur in auriculo-condylar syndrome includecupped ears, ears with fewer folds and grooves than usual (described as "simple"), narrow ear canals, small skin tags in front of or behind the ears, and ears that are rotated backward. Some affected individuals also have hearing loss.

Abnormalities of the mandible are another characteristic feature of auriculo-condylar syndrome. These abnormalities often include an unusually small chin (micrognathia) and malfunction of thetemporomandibular joint (TMJ), which connects the lower jaw to the skull. Problems with the TMJ affect how the upper and lower jaws fit together and can make it difficult to open and close the mouth. The term "condylar" in the name of the condition refers to the mandibular condyle, which is the upper portion of the mandible that forms part of the TMJ.

Other features of auriculo-condylar syndrome can include prominent cheeks, an unusually small mouth (microstomia), differences in the size and shape of facial structures between the right and left sides of the face (facial asymmetry), and an opening in the roof of the mouth (cleft palate). These features vary, even among affected members of the same family.

Auriculoosteodysplasia

Auriculoosteodysplasia is a rare disorder characterized mainly by abnormal ears and multiple bone development anomalies and in this condition it is characterized by multiple osseous dysplasia, characteristic ear shape (elongation of the lobe that is attached and accompanied by a small, slightly posterior lobule) and somewhat short stature. 

Autism with port-wine stain

A port wine stain is a type of birthmark. It is an irregularly shaped, reddish, flat area of blood vessels on the surface of the skin.

Auto-brewery syndrome

Auto-brewery syndrome (ABS) (also known as gut fermentation syndrome, endogenous ethanol fermentation or drunkenness disease) is a condition characterized by the fermentation of ingested carbohydrates in the gastrointestinal tract of the body caused by bacteria or fungi. ABS is a rare medical condition in which intoxicating quantities of ethanol are produced through endogenous fermentation within the digestive system. The organisms responsible for ABS include various yeasts and bacteria, including Saccharomyces cerevisiae, S. boulardii, Candida albicans, C. tropicalis, C. krusei, C. glabrata, C. kefyr, C. parapsilosis, Klebsiella pneumoniae, and Enterococcus faecium. These organisms use lactic acid fermentation or mixed acid fermentation pathways to produce an ethanol end product. The ethanol generated from these pathways is absorbed in the small intestine, causing an increase in blood alcohol concentrations that produce the effects of intoxication without the consumption of alcohol.

Researchers speculate the underlying causes of ABS are related to prolonged antibiotic use, poor nutrition and/or diets high in carbohydrates, and to pre-existing conditions such as diabetes and genetic variations that result in improper liver enzyme activity. In the last case, decreased activity of aldehyde dehydrogenase can result in accumulation of ethanol in the gut, leading to fermentation. Any of these conditions, alone or in combination, could cause ABS, and result in dysbiosis of the microbiome.

Another variant, urinary auto-brewery syndrome, is when the fermentation occurs in the urinary bladder rather than the gut.

Claims of endogenous fermentation have been attempted as a defense against drunk driving charges, some of which have been successful, but the condition is so rare and under-researched they are currently not substantiated by available studies

Autoimmune enteropathy

Autoimmune enteropathy (AIE) is a rare disorder of the immune system condition that affects infants, young children and (rarely) adults causing severe diarrhea, vomiting, and other morbidities of the digestive tract. AIE causes malabsorption of food, vitamins, and minerals often necessitating replacement fluids and total parenteral nutrition. 

There are 3 types of autoimmune enteropathy:

Type 1: IPEX syndrome: Immune dysregulation, Polyendocrinopathy, Enteropathy, X – linked syndrome, which is caused by a mutation in the FOXP3 gene. This can only affect boys.

Type 2: IPEX-like, which manifests similarly to IPEX syndrome but without recognizable mutations in the FOXP3 gene. This can affect both genders and includes a variety of manifestations of varying severity.

Type 3: Autoimmune manifestations primarily limited to the GI tract. This can affect both genders and may also be considered IPEX-like.

There is considerable overlap in these disorders, and it is often unclear how to properly distinguish between them as the responsible genes are generally poorly understood at this time.

Autoimmune hemolytic anemia

Autoimmune hemolytic anemia occurs when antibodies directed against the person's own red blood cells (RBCs) cause them to burst (lyse), leading to insufficient plasma concentration. The lifetime of the RBCs is reduced from the normal 100–120 days to just a few days in serious cases. The intracellular components of the RBCs are released into the circulating blood and into tissues, leading to some of the characteristic symptoms of this condition. The antibodies are usually directed against high-incidence antigens, therefore they also commonly act on allogenic RBCs (RBCs originating from outside the person themselves, e.g. in the case of a blood transfusion) AIHA is a relatively rare condition, affecting one to three people per 100,000 per year. There are two main types of autoimmune hemolytic anemia:warm antibody hemolytic anemia and cold antibody hemolytic anemia.

Autoimmune hepatitis

Autoimmune hepatitis is a chronic, autoimmune disease of the liver that occurs when the body's immune system attacks liver cells causing the liver to be inflamed. Common initial symptoms include fatigue or muscle aches or signs of acute liver inflammation including fever, jaundice, and right upper quadrant abdominal pain. Individuals with autoimmune hepatitis often have no initial symptoms and the disease is detected by abnormal liver function tests.

Anomalous presentation of human leukocyte antigen (HLA) class II on the surface of liver cells, possibly due to genetic predisposition or acute liver infection, causes a cell-mediated immune response against the body's own liver, resulting in autoimmune hepatitis. This abnormal immune response results in inflammation of the liver, which can lead to further symptoms and complications such as fatigue and cirrhosis. The disease may occur in any ethnic group and at any age, but is most often diagnosed in patients between age 40 and 50.

Autoimmune Inner Ear disease

Autoimmune inner ear disease is a syndrome of progressive hearing loss and/or dizziness that is caused by antibodies or immune cells which are attacking the inner ear. In most cases, there is reduction of hearing accompanied by tinnitus. The disease results in progressivesensorineural hearing loss (SNHL) that acts bilaterally and asymmetrically, and sometimes affects an individual's vestibular system. It is known in literature that consensus that AIED is the result of antibodies or other immune cells that cause damage to structures of the inner ear such as the cochlea and vestibular system.

Autoimmune lymphoproliferative syndrome

Autoimmune lymphoproliferative syndrome (ALPS) is an inherited disorder in which the body cannot properly regulate the number of immune system cells (lymphocytes). ALPS is characterized by the production of an abnormally large number of lymphocytes (lymphoproliferation). Accumulation of excess lymphocytes results in enlargement of the lymph nodes (lymphadenopathy), the liver (hepatomegaly), and the spleen (splenomegaly). People with ALPS have an increased risk of developing cancer of the immune system cells (lymphoma) and may also be at increased risk of developing other cancers.

Autoimmune disorders are also common in ALPS. Autoimmune disorders occur when the immune system malfunctions and attacks the body's own tissues and organs. Most of the autoimmune disorders associated with ALPS target and damage blood cells. For example, the immune system may attack red blood cells (autoimmune hemolytic anemia), white blood cells (autoimmune neutropenia), or platelets (autoimmune thrombocytopenia). Less commonly, autoimmune disorders that affect other organs and tissues occur in people with ALPS. These disorders can damage the kidneys (glomerulonephritis), liver (autoimmune hepatitis), eyes (uveitis), nerves (Guillain-Barre syndrome), or the connective tissues (systemic lupus erythematosus) that provide strength and flexibility to structures throughout the body.

Autoimmune myocarditis

Autoimmune myocarditis is an autoimmune disease that affects the heart. The condition is characterized by inflammation of the heart muscle (myocardium). Some people with autoimmune myocarditis have no noticeable symptoms of the condition.

Autoimmune oophoritis

Autoimmune oophoritis is an autoimmune inflammation of ovaries resulting in their destruction, atrophy, and fibrosis with a loss of fertility and ovary hormonal production. These changes stop the ovaries from working normally.

Autoimmune peripheral neuropathy

Peripheral neuropathy describes damage to the peripheral nervous system, the vast communications network that transmits information from the brain and spinal cord (the central nervous system) to every other part of the body. 

Autoimmune polyglandular syndrome type 1

Autoimmune polyglandular syndrome, type 1 is an inherited condition that affects many of the body's organs. It is one of many autoimmune diseases, which are disorders that occur when the immune system malfunctions and attacks the body's tissues and organs by mistake. It is characterized by autoimmune polyendocrinopathy (APE), candidiasis (C) and ectodermal dysplasia (ED).

Autoimmune progesterone dermatitis

Autoimmune progesterone dermatitis (APD) is primarily characterized by a recurrent skin rash that varies in severity depending on the phase of the menstrual cycle. The rash generally appears during the second half of the cycle when levels of the hormone, progesterone, begin to rise and it subsides shortly after menstruation. As progesterone production is linked to menstrual cycles, the rash occurs usually in the week before menstruation until a few days after menstruation starts.