Diseases

Storm syndrome

A rare progressive genetic disorder characterized by premature aging and heart disease which results in premature death.

Sturge-Weber syndrome

Sturge-Weber syndrome (SWS) is a rare vascular disorder characterized by the association of a facial birthmark called a port-wine birthmark, abnormal blood vessels in the brain, and eye abnormalities such as glaucoma.

Stuve-Wiedemann syndrome

Stuve-Wiedemann syndrome, originally described in 1971, is a rare abnormality that belongs to the group of the bent-bone dysplasias and is haracterized by bowing of the lower limbs, with internal cortical thickening, wide metaphyses with abnormal trabecular pattern, and campodactyly. Additional features include feeding and swallowing difficulties, as well as respiratory distress and hyperthermic episodes, which cause death in the first months of life.

Subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis a rare condition that is caused by a measles infection acquired earlier in life. Signs and symptoms of the condition primarily affect the central nervous system and often develop approximately 7 to 10 years after a person recovers from the measles. Affected people may initially experience behavioral changes, dementia, and disturbances in motor function. In the late stages of the disease, affected people often progress to a comatose state, and then to a persistent vegetative state. Ultimately, many people with SSPE succumb to fever, heart failure, or the brain's inability to continue controlling the autonomic nervous system. It is unclear why some people develop SSPE after they have seemingly recovered from the measles while others do not. Researchers suspect that SSPE may be due to an abnormal immune response or a mutant form of the measles virus that causes a persistent infection within the central nervous system.

Subcortical laminar heterotopia

A rare inherited disorder where a part of the brain tissue is misplaced during development. More specifically, the abnormal tissue is found in the subcortical part of the brain.

Subependymal nodular heterotopia

A rare inherited disorder where a part of the brain tissue is misplaced during development. More specifically, nodules of the abnormal tissue is found in the subependymal part of the brain.

Subependymoma

Subependymomas are composed of glial tumor cell clusters embedded in an abundant fibrillary matrix with frequent microcystic change. It is a histologic grade I tumor in the WHO classification

Subpulmonary stenosis

A narrowing in the artery that allows blood to flow from the right heart ventricle to the lungs in order to be oxygenated. Severity of symptoms is determined by the degree of narrowing.

Subvalvular aortic stenosis

SAS or subvalvular aortic stenosis. Sub aortic stenosis is the second most common canine heart malformation and is defined as an "obstruction of the left ventricular outflow tract that ranges in severity from an incomplete fibrous ridge to a fibromuscular tunnel", and lies just under the aortic valve.

Succinic acidemia

A rare metabolic disorder characterized by high levels of succinic acid in the blood.

Succinic semialdehyde dehydrogenase deficiency

Succinic semialdehyde dehydrogenase deficiency (SSADHD), also known as 4-hydoxybutyric aciduria or gamma-hydoxybutyric aciduria, is a rare autosomal recessive disorder[1] of the degradation pathway of the inhibitory neurotransmitter γ-aminobutyric acid, or GABA. The disorder has been identified in approximately 350 families, with a significant proportion being consanguineous families.

Succinyl-CoA acetoacetate transferase deficiency

A very rare metabolic disorder involving an enzyme (Succinyl-CoA acetoacetate transferase) deficiency which prevents ketones being metabolized. Physical stress on the body (infection, exhaustion) can trigger an episode of ketosis, vomiting and rapid breathing.

Sudan Virus

Sudan virus disease is a viral hemorrhagic fever disease, belonging to the same family as Ebola virus disease. It is caused by Sudan virus (SUDV). It is a severe disease with high case fatality. It is typically characterized by acute onset of fever with non-specific symptoms/signs (e.g., abdominal pain, anorexia, fatigue, malaise, myalgia, sore throat) usually followed several days later by nausea, vomiting, diarrhoea, and occasionally a variable rash. Hiccups may occur. Severe illness may include hemorrhagic manifestations (e.g., bleeding from puncture sites, ecchymoses, petechiae, visceral effusions), encephalopathy, shock/hypotension, multi-organ failure, spontaneous abortion in infected pregnant women. Individuals who recover may experience prolonged sequelae (e.g., arthralgia, neurocognitive dysfunction, uveitis sometimes followed by cataract formation), and clinical and subclinical persistent infection may occur in immune-privileged compartments (e.g., CNS, eyes, testes). Person-to-person transmission occurs by direct contact with blood, other bodily fluids, organs, or contaminated surfaces and materials with risk beginning at the onset of clinical signs and increasing with disease severity. Family members, healthcare providers, and participants in burial ceremonies with direct contact with the deceased are at particular risk. The incubation period ranges from 2 to 21 days, but typically is 7–11 days.

Sudden Arrhythmia Death Syndrome

Sudden Arrhythmia Death Syndrome (SADS), otherwise known as Long QT Syndrome, is a disorder of the electrical system of the heart. The problem centres on the length of time it takes the electrical system to recharge following a heatbeat. This is known as the QT interval. People who have a long QT interval are more vulnerable to a very fast, abnormal heart rhythm, or arrhythmia. When this rhythm occurs, no blood is pumped out from the heart, and the brain quickly becomes deprived of blood causing sudden loss of consciousness and sudden death.

Sudden infant death syndrome

Sudden infant death syndrome (SIDS), also known as cot death or crib death, is the sudden unexplained death of a child less than one year of age. Diagnosis requires that the death remains unexplained even after a thorough autopsy and detailed death scene investigation. SIDS usually occurs during sleep. Typically death occurs between the hours of 00:00 and 09:00. There is usually no evidence of struggle and no noise produced.

Sugarman syndrome

A rare genetic disorder characterized by oral frenula, oral clefts, underdeveloped nose flapss and finger, teeth and eye abnormalities.

Sulfite oxidase deficiency

Sulfite oxidase deficiency is an inborn error of the metabolism of sulfated amino acids. Individuals affected with sulfite oxidase deficiency most commonly present in the neonatal period with intractable seizures, characteristic dysmorphic features, and profound mental retardation.

Summitt syndrome

A very rare genetic disorder abnormalities of the head, hands and feet as well as obesity.

SUNCT headache

A syndrome involving a short-lived pain around one eye or on one side of the head as well as well as fluid being forced into the conjunctiva and mucous membranes of the eyelids.

Superficial siderosis of the central nervous system

A rare disorder where hemosiderin (free iron) is deposited in parts of the central nervous system (brain and spinal cord tissue). It is often caused by repeated periods of bleeding in the brain (subarachnoid space).

Superior mesenteric artery syndrome

A rare condition where the third portion of the duodenum is compressed between two large blood vessels - the aorta and superior mesenteric artery.

Superior vena cava syndrome

A condition caused by compression or obstruction to the normal circulation of the superior vena cava which carries deoxygenated blood from the body tissues back to the heart

Supranuclear ocular palsy

Impaired eye movement due to a brain problem. The type of eye movement problems is determined by the location of the brain abnormality