It is associated with cathepsin A.This disease is due to mutations in the CTSA gene which encodes the protective protein/cathepsin A (PPCA). This in turn leads to a secondary deficiency of beta-galactosidase (GLB1) and neuraminidase 1 (NEU1).There are three distinct CTSA isoforms.

A prenatal diagnosis was made by Kleijer et al. in 1979 by measuring beta-galactosidase and neuraminidase activities in cultured amniotic fluid cells.

In terms of causation several mutations in the MANBA gene is the cause of beta-mannosidosis. The cytogenetic location of the gene is 4q24, furthermore the condition is inherited in an autosomal recessive manner

The GM1 gangliosidoses (or GM1 gangliosidos"i"s) are caused by a deficiency of beta-galactosidase, with resulting abnormal storage of acidic lipid materials in cells of the central and peripheral nervous systems, but particularly in the nerve cells.

GM1 Gangliosidoses are inherited, autosomal recessive sphingolipidoses, resulting from marked deficiency of Acid Beta Galactosidase.

The number of events that can lead to the development of PSH symptoms is many. The exact pathways or causes for the development of the syndrome are not known. Traumatic brain injury, hypoxia, stroke, anti-NMDA receptor encephalitis (although further associations are being explored), injury of the spinal cord, and many other forms of brain injury can cause onset of PSH. Even more obscure diseases such as intracranial tuberculoma have been seen to cause onset of paroxysmal sympathetic hyperactivity. It is observed that these injuries lead to the development of PSH or are seen in conjunction with PSH, but the pathophysiology behind these diseases and the syndrome is not well understood.

Dahlberg Borer Newcomer syndrome is a rare autosomal X-linked recessive genetic condition characterized by a prolapse of the bicuspid valve, progressive kidney failure, congenital lymphedema, hypoparathyroidism, and very short end bones of fingers. Treatment for this condition is based on its symptoms. These treatments may include manual lymphatic drainage, consumption of beta blockers or anticoagulants for the bicuspid valve prolapse and vitamin D or calcium carbonate tablets for the hypoparathyroidism.

This condition is also known as Lymphedema hypoparathyroidism syndrome, Hypoparathyroidism lymphedema syndrome, and simply Dahlberg syndrome.

Hyperekplexia ("exaggerated surprise") is a neurologic disorder classically characterised by pronounced startle responses to tactile or acoustic stimuli and hypertonia. The hypertonia may be predominantly truncal, attenuated during sleep and less prominent after a year of age. Classic hyperekplexia is caused by genetic mutations in a number of different genes, all of which play an important role in glycine neurotransmission. Glycine is used by the central nervous system as an inhibitory neurotransmitter. Hyperekplexia is generally classified as a genetic disease, but some disorders can mimic the exaggerated startle of hyperekplexia.

GM2-gangliosidosis, AB variant is a rare, autosomal recessive metabolic disorder that causes progressive destruction of nerve cells in the brain and spinal cord. It has a similar pathology to Sandhoff disease and Tay-Sachs disease. The three diseases are classified together as the GM2 gangliosidoses, because each disease represents a distinct molecular point of failure in the activation of the same enzyme, beta-hexosaminidase. AB variant is caused by a failure in the gene that makes an enzyme cofactor for beta-hexosaminidase, called the GM2 activator.

Paroxysmal sympathetic hyperactivity (PSH) is a syndrome that causes episodes of increased activity of the sympathetic nervous system. Hyperactivity of the sympathetic nervous system can manifest as increased heart rate, increased respiration, increased blood pressure, diaphoresis, and hyperthermia.

Previously, this syndrome has been identified as general dysautonomia but now is considered a specific form of it. It has also been referred to as paroxysmal sympathetic instability with dystonia, or PAID, and sympathetic storm. Recently, however, studies have adopted the name paroxysmal sympathetic hyperactivity to ensure specificity. PSH is observed more in younger patients than older ones. It is also seen more commonly in men than women. There is no known reason why this is the case, although it is suspected pathophysiological links may exist. In patients surviving traumatic brain injury, the occurrence of these episodes is one in every three. PSH can also be associated with severe anoxia, subarachnoid and intracerebral hemorrhage, and hydrocephalus.

The most commonly effective treatment is clonazepam, which leads to the increased efficacy of another inhibitory neurotransmitter, GABA. There are anecdotal reports of the use of Levetiracetam in genetic and acquired hyperekplexia. During attacks of hypertonia and apnea, the limbs and head may be flexed towards the trunk in order to dissipate the symptoms. This is named the Vigevano maneuver after the doctor who invented it.

Beta-mannosidosis, also called lysosomal beta-mannosidase deficiency, is a disorder of oligosaccharide metabolism caused by decreased activity of the enzyme beta-mannosidase. This enzyme is coded for by the gene "MANBA", located at 4q22-25. Beta-mannosidosis is inherited in an autosomal recessive manner. Affected individuals appear normal at birth, and can have a variable clinical presentation. Infantile onset forms show severe neurodegeneration, while some children have intellectual disability. Hearing loss and angiokeratomas are common features of the disease.

Dup15q syndrome is the common name for chromosome 15q11.2-q13.1 duplication syndrome. This is a neurodevelopmental disorder, caused by the partial duplication of Chromosome 15, that confers a strong risk for autism spectrum disorder, epilepsy, and intellectual disability. It is the most common genetic cause of autism, accounting for approximately 1-3% of cases. Dup15q syndrome includes both interstitial duplications and isodicentric duplications (i.e., Idic15) of 15q11.2-13.1.

Important genes likely involved in the etiology of Dup15q syndrome include "UBE3A", "GABRA5", "GABRB3", and "GABRG3". "UBE3A" is a ubiquitin-protein ligase that is involved in targeting proteins for degradation and plays an important role in synapse function. "GABRA5", "GABRB3", and "GABRG3" are gamma aminobutyric acid type A (GABA) receptor subunit genes and are likely important in Dup15q syndrome given the established role of GABA in the etiologies of autism and epilepsy.

People with diabetes show an increased rate of urinary tract infection. The reason is bladder dysfunction that is more common in diabetics than in non-diabetics due to diabetic nephropathy. When present, nephropathy can cause a decrease in bladder sensation, which in turn, can cause increased residual urine, a risk factor for urinary tract infections.

Brittle asthma is a type of asthma distinguishable from other forms by recurrent, severe attacks.

There are two subtypes divided by symptoms: Type 1 and Type 2, depending on the stability of the patient's maximum speed of expiration, or peak expiratory flow rate (PEFR). Type 1 is characterized by sustained, chronic variability of PEFR, while type 2 is distinguished by sudden unpredictable drops in PEFR where asthma symptoms are otherwise well controlled and the function of the lungs is not substantially impaired.

Brittle asthma is one of the "unstable" subtypes of "difficult asthma", a term used to characterize the less than 5% of asthma cases that do not respond to maximal inhaled treatment, including high doses of corticosteroids combined with additional therapies such as long-acting beta-2 agonists.

Mutations in the GM2A gene cause GM2-gangliosidosis, AB variant. This condition is inherited in an autosomal recessive pattern.

The GM2A gene provides instructions for making a protein called the GM2 activator. This protein is required for the normal function of beta-hexosaminidase A, a critical enzyme in the nervous system that breaks down a lipid called GM2 ganglioside. If mutations in both alleles at this locus disrupt the activity of the GM2 activator, beta-hexosaminidase A cannot perform its normal function. As a result, gangliosides accumulate in the central nervous system until they interfere with normal biological processes. Progressive damage caused by buildup of gangliosides leads to the destruction of nerve cells.

GM2-gangliosidosis, AB variant is extremely rare. In contrast with both Tay-Sachs disease and Sandhoff disease, in which many mutant polymorphic alleles have been discovered, including pseudodeficiency alleles, very few GM2A mutations have been reported. When AB variant is reported, in often occurs with consanguineous parents or in genetically isolated populations.

GM2A is expressed in many tissues, and the GM2 activator protein has been reported to have other cellular functions. Because AB variant is so rarely diagnosed, it is likely that most mutations of GM2A are fatal at the embryionic or fetal stage of development in homozygotes and genetic compounds, and thus are never observed clinically.

Sexual dysfunction in diabetics is often a result of physical factors such as nerve damage and/or poor circulation, and psychological factors such as stress and/or depression caused by the demands of the disease.

Onset of adult GM1 is between ages 3 and 30.

Symptoms include muscle atrophy, neurological complications that are less severe and progress at a slower rate than in other forms of the disorder, corneal clouding in some patients, and dystonia (sustained muscle contractions that cause twisting and repetitive movements or abnormal postures). Angiokeratomas may develop on the lower part of the trunk of the body. Most patients have a normal size liver and spleen.

Prenatal diagnosis is possible by measurement of Acid Beta Galactosidase in cultured amniotic cells.

Individuals with Dup15q syndrome are at high risk for epilepsy, autism, and intellectual disability. Motor impairments are very common in individuals with the disorder. Rates of epilepsy in children with isodicentric duplications are higher than in children with interstitial duplications. A majority of patients with either duplication type (isodicentric or interstitial) have a history of gastrointestinal problems.

A study at the University of California, Los Angeles (UCLA) of 13 children with Dup15q syndrome and 13 children with nonsyndromic ASD (i.e., autism not caused by a known genetic disorder) found that, compared to children with nonsyndromic autism, children with Dup15q had significantly lower autism severity as measured by the Autism Diagnostic Observation Schedule (ADOS) (all children in the study met diagnostic criteria for ASD). However, children with Dup15q syndrome had significantly greater motor impairment and impairment of daily living skills than children in the nonsyndromic ASD group. Within the Dup15q syndrome cohort, children with epilepsy had greater cognitive impairment.

It is estimated that between 6-50% of all persons, depending on population, diagnosed with type 2 diabetes might actually have LADA. This number accounts for an estimated 5–10% of the total diabetes population in the U.S. or, as many as 3.5 million persons with LADA. People with LADA typically have a normal BMI or may be underweight due to weight loss prior to diagnosis. Some people with LADA, however, may be overweight to mildly obese.

Contrary to popular belief, some people having LADA do carry a family history of type 2 diabetes.

This is a form of dysautonomia but differentiated from familial dysautonomia by a lack of familial dysautonomic symptoms such as loss of sense of pain and smell. While L-threo-DOPS has been described as being "very effective for restoring noradrenergic tone and correcting postural hypotension, response to treatment is variable and the long-term and functional outcome is unknown."

Researchers have put together retrospective data collections in order to better under the progression of this orphan disease. Most studies show a perinatal period marked by inadequacy of the ANS to control blood pressure, blood sugar, and body temperature. The experiences of orthostatic hypotension, exercise intolerance, and "traumatic morbidity related to falls and syncope" have been documented later in lives of people with this condition. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation, outcome of these diseases, their impact on the quality of life of patients, and for evaluating diagnostic and therapeutic strategies, a patient registry was established by the non-commercial International Working Group on Neurotransmitter Related Disorders (iNTD).

Ecthyma is a variation of impetigo, presenting at a deeper level of tissue.

It is usually associated with Group A (beta-hemolytic) Streptococcus (abbreviated GAS).

Untreated individuals with DβH deficiency should avoid hot environments, strenuous exercise, standing still, and dehydration.

Inhalation of an agonist for the beta-2 adrenergic receptor, such as Salbutamol, Albuterol (US), is the most common treatment for asthma. Polymorphisms of the beta-2 receptor play a role in tachyphylaxis. Expression of the Gly-16 allele (glycine at position 16) results in greater receptor downregulation by endogenous catecholamines at baseline compared to Arg-16. This results in a greater single-use bronchodilator response in individuals homozygous for Arg-16 compared to Gly-16 homozygotes. However, with regular beta-2 agonist use, asthmatic Arg-16 individuals experience a significant decline in bronchodilator response. This decline does not occur in Gly-16 individuals. It has been proposed that the tachyphylactic effect of regular exposure to exogenous beta-2 agonists is more apparent in Arg-16 individuals because their receptors have not been downregulated prior to agonist administration.

Insulitis is an inflammation of the islets of Langerhans, a collection of endocrine tissue located in the pancreas. The islets containing the pancreatic β-cells, and in some cases, the exocrine tissues, become infiltrated by T and B lymphocytes, macrophages and dendritic cells. This innate immune cell and lymphocyte infiltration can result in destruction of the insulin producing beta cells of the islets, and clinical diabetes. Insulitis is often studied in the multiple low dose streptozotocin (MLDS) mouse model or the non-obese diabetic (NOD) mouse model of type 1 diabetes. The chemokine family of proteins may play a key role in promoting leukocytic infiltration into the pancreas prior to pancreatic beta-cell destruction.

MODY 3 is a form of maturity onset diabetes of the young.

MODY 3 (also known as HNF1A-MODY) is caused by mutations of the HNF1-alpha; gene, a homeobox gene on chromosome 12. This is the most common type of MODY in populations with European ancestry, accounting for about 70% of all cases in Europe. HNF1α is a transcription factor (also known as transcription factor 1, TCF1) that is thought to control a regulatory network (including, among other genes, HNF1α) important for differentiation of beta cells. Mutations of this gene lead to reduced beta cell mass or impaired function. MODY 1 and MODY 3 diabetes are clinically similar. About 70% of people develop this type of diabetes by age 25 years, but it occurs at much later ages in a few. This type of diabetes can often be treated with sulfonylureas with excellent results for decades. However, the loss of insulin secretory capacity is slowly progressive and most eventually need insulin.

This is the form of MODY which can most resemble ordinary type 1 diabetes, and one of the incentives for diagnosing it is that insulin may be discontinued or deferred in favor of oral sulfonylureas. Some people treated with insulin for years due to a presumption of type 1 diabetes have been able to switch to pills and discontinue injections. Long-term diabetic complications can occur if the glucose is not adequately controlled.

High-sensitivity measurements of CRP may help to distinguish between HNF1A-MODY and other forms of diabetes