Life expectancy with Fabry disease for males was 58.2 years, compared with 74.7 years in the general population, and for females 75.4 years compared with 80.0 years in the general population, according to registry data from 2001 to 2008. The most common cause of death was cardiovascular disease, and most of those had received kidney replacements.

Pogosta disease is a viral disease, established to be identical with other diseases, Karelian fever and Ockelbo disease. The names are derived from the words Pogosta, Karelia and Ockelbo, respectively.

The symptoms of the disease include usually rash, as well as mild fever and other flu-like symptoms; in most cases the symptoms last less than 5 days. However, in some cases, the patients develop a painful arthritis. There are no known chemical agents available to treat the disease.

It has long been suspected that the disease is caused by a Sindbis-like virus, a positive-stranded RNA virus belonging to the Alphavirus genus and family Togaviridae. In 2002 a strain of Sindbis was isolated from patients during an outbreak of the Pogosta disease in Finland, confirming the hypothesis.

This disease is mainly found in the Eastern parts of Finland; a typical Pogosta disease patient is a middle-aged person who has been infected through a mosquito bite while picking berries in the autumn. The prevalence of the disease is about 100 diagnosed cases every year, with larger outbreaks occurring in 7-year intervals.

In infantile Krabbe disease, death usually occurs in early childhood. A 2011 study found 1, 2, 3 year survival rates of 60%, 26%, and 14%, respectively. A few survived for longer and one was still alive at age 13. Patients with late-onset Krabbe disease tend to have a slower progression of the disease and live significantly longer.

Infants with Schindler disease tend to die within 4 years of birth, therefore, treatment for this form of the disease is mostly palliative. However, Type II Schindler disease, with its late onset of symptoms, is not characterized by neurological degeneration. There is no known cure for Schindler disease, but bone marrow transplants have been trialed, as they have been successful in curing other glycoprotein disorders.

Urbach–Wiethe disease is very rare; there are fewer than 300 reported cases in medical literature. Although Urbach–Wiethe disease can be found worldwide, almost a quarter of reported diagnoses are in South Africa. Many of these are in patients of Dutch, German, and Khoisan ancestry. This high frequency is thought to be due to the founder effect. Due to its recessive genetic cause and the ability to be a carrier of the disease without symptoms, Urbach–Wiethe disease often runs in families. In some regions of South Africa, up to one in 12 individuals may be carriers of the disease. Most of the case studies involving Urbach–Wiethe disease patients involve only one to three cases and these cases are often in the same family. Due to its low incidence, it is difficult to find a large enough number of cases to adequately study the disease.

Fabry disease is estimated to occur in one in 40,000 to one in 120,000 live births.

Krabbe disease occurs in about one in 100,000 births. A higher incidence, about six in 1,000, has been reported in certain communities in Israel. Scandinavian countries have comparatively high rates of the disease, reported to be one in 50,000 births.

Most children with Farber disease die by age 2, usually from lung disease. In one of the most severe forms of the disease, an enlarged liver and spleen (hepatosplenomegaly) can be diagnosed soon after birth. Children born with this form of the disease usually die within 6 months.

There is no specific treatment for Farber disease. Corticosteroids may be prescribed to relieve pain. Bone marrow transplants may improve granulomas (small masses of inflamed tissue) on patients with little or no lung or nervous system complications. Older patients may have granulomas surgically reduced or removed.

Schindler disease, also known as Kanzaki disease and alpha-N-acetylgalactosaminidase deficiency is a rare disease found in humans. This lysosomal storage disorder is caused by a deficiency in the enzyme alpha-NAGA (alpha-N-acetylgalactosaminidase), attributable to mutations in the NAGA gene on chromosome 22, which leads to excessive lysosomal accumulation of glycoproteins. A deficiency of the alpha-NAGA enzyme leads to an accumulation of glycosphingolipids throughout the body. This accumulation of sugars gives rise to the clinical features associated with this disorder. Schindler disease is an autosomal recessive disorder, meaning that one must inherit an abnormal allele from both parents in order to have the disease.

There are no currently known causes of this disease. There are studies currently proposing several theories of the causes which include inflammation of the adipose tissue, nervous system malfunction and endocrine malfunction. None of the theories that are currently proposed have been found viable. Since little is known about Dercum's disease, there are currently no known modes of prevention. Some hypotheses state that maintaining a healthy weight and diet can help prevent Dercum's although it has not been proven.

Dercum's disease can affect people of any gender and of any age. The majority of cases are linked to women between the ages of 45 and 60, who are overweight and postmenopausal. Due to the difficulty of diagnosis of this disease, many cases are underreported or misdiagnosed and it is difficult to understand what part of the population is affected by it the most.

The most common type of heavy chain disease is the IgA type, known as αHCD. The most common type of αHCD is the gastrointestinal form (known as immunoproliferative small intestine disease or IPSID), but it has also been reported in the respiratory tract, and other areas of the body.

There are four forms:

- alpha chain disease (Seligmann's disease)

- gamma chain disease (Franklin's disease)

- mu chain disease

- delta chain disease

The increased incidence of Crohn's in the industrialized world indicates an environmental component. Crohn's is associated with an increased intake of animal protein, milk protein and an increased ratio of omega-6 to omega-3 polyunsaturated fatty acids.

Those who consume vegetable proteins appear to have a lower incidence of Crohn's disease. Consumption of fish protein has no association.

Smoking increases the risk of the return of active disease (flares). The introduction of hormonal contraception in the United States in the 1960s is associated with a dramatic increase in incidence, and one hypothesis is that these drugs work on the digestive system in ways similar to smoking. Isotretinoin is associated with Crohn's. Although stress is sometimes claimed to exacerbate Crohn's disease, there is no concrete evidence to support such claim. Dietary microparticles, such as those found in toothpaste, have been studied as they produce effects on immunity, but they were not consumed in greater amounts in patients with Crohn's.

The twins require the use of wheelchairs for mobility and are unable to speak without the assistance of electronic speaking aids. They experience persistent and painful muscle spasms which are worsened by emotional distress. They are currently living with their parents, with the assistance of hospice workers. Doctors continue to administer tests to the twins in search of a treatment.

Sandhoff disease, also known as Sandhoff–Jatzkewitz disease, variant 0 of GM2-Gangliosidosis or Hexosaminidase A and B deficiency, is a lysosomal genetic, lipid storage disorder caused by the inherited deficiency to create functional beta-hexosaminidases A and B. These catabolic enzymes are needed to degrade the neuronal membrane components, ganglioside GM2, its derivative GA2, the glycolipid globoside in visceral tissues, and some oligosaccharides. Accumulation of these metabolites leads to a progressive destruction of the central nervous system and eventually to death. The rare autosomal recessive neurodegenerative disorder is clinically almost indistinguishable from Tay–Sachs disease, another genetic disorder that disrupts beta-hexosaminidases A and S. There are three subsets of Sandhoff disease based on when first symptoms appear: classic infantile, juvenile and adult late onset.

The disease appears to be progressive in nature. The Fields twins started having problems when they were four years old. By the time they had reached the age of nine, they were having difficulty walking and needed frames to assist them with walking. Their muscles have been gradually deteriorating over time. The disease affects the twins' nerves, causing them to make involuntary muscle movements such as trembling in the hands.

The extent of the disease is still unknown as the two women are only 21. However, the disease has had no apparent effect on their brains or personalities. Doctors do not know if the disease is fatal and, if so, what the life expectancy of one with this disease is. If the cause of the disease is genetic, there is a chance that the twins could pass it on to their future children.

Urbach–Wiethe disease is typically not a life-threatening condition. The life expectancy of these patients is normal as long as the potential side effects of thickening mucosa, such as respiratory obstruction, are properly addressed. Although this may require a tracheostomy or carbon dioxide laser surgery, such steps can help ensure that individuals with Urbach–Wiethe disease are able to live a full life. Oral dimethyl sulfoxide (DMSO) has been shown to reduce skin lesions, helping to minimize discomfort for these individuals.

Sphingolipidoses (singular "sphingolipidosis") are a class of lipid storage disorders relating to sphingolipid metabolism. The main members of this group are Niemann–Pick disease, Fabry disease, Krabbe disease, Gaucher disease, Tay–Sachs disease and metachromatic leukodystrophy. They are generally inherited in an autosomal recessive fashion, but notably Fabry disease is X-linked recessive. Taken together, sphingolipidoses have an incidence of approximately 1 in 10,000, but substantially more in certain populations such as Ashkenazi Jews. Enzyme replacement therapy is available to treat mainly Fabry disease and Gaucher disease, and people with these types of sphingolipidoses may live well into adulthood. The other types are generally fatal by age 1 to 5 years for infantile forms, but progression may be mild for juvenile- or adult-onset forms.

The disease is regarded as extremely rare, with an incidence (new number of cases per year) of one case per million people. The patients are predominantly male (86% in a survey of American patients), although in some countries the rate of women receiving a diagnosis of Whipple's disease has increased in recent years. It occurs predominantly in those of Caucasian ethnicity, suggesting a genetic predisposition in that population.

"T. whipplei" appears to be an environmental organism that is commonly present in the gasterointestinal tract but remains asymptomatic. Several lines of evidence suggest that some defect—inherited or acquired—in immunity is required for it to become pathogenic. The possible immunological defect may be specific for "T. whipplei", since the disease is not associated with a substantially increased risk of other infections.

The disease is usually diagnosed in middle age (median 49 years). Studies from Germany have shown that age at diagnosis has been rising since the 1960s.

Adult-onset Still's disease (AOSD) is a form of Still's disease, a rare systemic autoinflammatory disease characterized by the classic triad of persistent high spiking fevers, joint pain, and a distinctive salmon-colored bumpy rash. The disease is considered a diagnosis of exclusion. Levels of the iron-binding protein ferritin may be elevated with this disorder. AOSD may present in a similar manner to other inflammatory diseases and to autoimmune diseases, which must be ruled out before making the diagnosis.

Prognosis is usually favorable but manifestations of the disease affecting the lungs, heart, or kidneys may occasionally cause severe life-threatening complications. It is treated first with steroids such as prednisone. Drugs that block the action of interleukin-1, such as anakinra, can be effective treatments when standard steroid treatments are insufficient.

Articles regarding Sandhoff disease frequencies among distinct groups of people contain discrepancies from one another. More than 25 mutations have been reported other than novel mutations.

One article says that Sandhoff disease is found commonly in individuals with a non-Jewish descent.

Others say that it is more commonly in:

- the Creole population of northern Argentina

- the indigenous Métis in Saskatchewan

- Christian Maronite communities from Cyprus

Discovery of several mutations in Ashkenazi Jews may reflect ascertainment bias rather than a high population frequency, because Ashkenazi Jews were the targeted population in a mass screening program for Tay-Sachs disease. Several rare SD mutations were discovered as researchers resolved cases of enzyme deficiency among suspected TSD carriers, but no cases of the disease itself have been reported.

However, since it is an autosomal recessive disease, it is likely found in any ethnic group passing from generation to generation through carriers without being expressed in their offspring. Even though the family may not have a history of Sandhoff disease, it is possible for two individuals to have a child with the disease. Since Sandhoff disease was only discovered in 1968, there are years the disease has gone undetected because of misdiagnoses.

With Behçet's disease as an intercurrent disease in pregnancy, the pregnancy does not have an adverse effect on the course of Behçet's disease and may possibly ameliorate its course. Still, there is a substantial variability in clinical course between patients and even for different pregnancies in the same patient. Also, the other way around, Behçet's disease confers an increased risk of pregnancy complications, miscarriage and Cesarean section.

Behçet's can cause male infertility, either as a result of the condition itself or of a side effect of concomitant medication such as Colchicine, which is known to lower sperm count.

Adult-onset Still's Disease is rare and has been described all over the world. The number of new cases per year is estimated to be 1.6 per 1,000,000 population. The number of people currently affected is estimated at 1.5 cases per 100,000-1,000,000 population. Onset is most common in two age ranges, between ages 15–25 and between ages of 36–46 years.

The symptoms of LSD vary, depending on the particular disorder and other variables such as the age of onset, and can be mild to severe. They can include developmental delay, movement disorders, seizures, dementia, deafness, and/or blindness. Some people with LSDhave enlarged livers (hepatomegaly) and enlarged spleens (splenomegaly), pulmonary and cardiac problems, and bones that grow abnormally.