The chronic inflammation present in MWS over time can lead to deafness. In addition, the prolonged inflammation can lead to deposition of proteins in the kidney, a condition known as amyloidosis.

The life span in patients with Schnitzler syndrome has not been shown to differ much from the general population. Careful follow-up is advised, however. A significant proportion of patients develops a lymphoproliferative disorder as a complication, most commonly Waldenström's macroglobulinemia. This may lead to symptoms of hyperviscosity syndrome. AA amyloidosis has also been reported in people with Schnitzler syndrome.

MWS occurs when a mutation in the "CIAS1" gene, encoding for NLRP3, leads to increased activity of the protein cryopyrin. This protein is partly responsible for the body's response to damage or infection. During these states, a cytokine called interleukin 1β is produced by an innate immune cell known as a macrophage. This cytokine interacts with a receptor on the surface of other immune cells to produce symptoms of inflammation such as fever, arthritis, and malaise. In MWS, the increased activity of cryopyrin leads to an increase in interleukin 1β. This leads to inflammation all throughout the body with the associated symptoms.

Marshall–Smith syndrome is not to be confused with:

- Marshall syndrome (aka.Periodic fever, aphthous stomatitis, pharyngitis and adenitis (PFAPA syndrome, see also: Periodic fever syndrome)

- Sotos (like) syndrome

- Weaver-Smith syndrome (WSS)

This is a rare condition with an incidence estimated to be less than 1 in a million live births. About 100 cases have been reported worldwide. The bulk of cases are sporadic but familial forms with autosomal dominant transmission have also been described.

After the first discovery and description of Marshall–Smith syndrome in 1971, research to this rare syndrome has been carried out.

- Adam, M., Hennekam, R.C.M., Butler, M.G., Raf, M., Keppen, L., Bull, M., Clericuzio, C., Burke, L., Guttacher, A., Ormond, K., & Hoyme, H.E. (2002). Marshall–Smith syndrome: An osteochondrodysplasia with connective tissue abnormalities. 23rd Annual David W. Smith Workshop on Malformations and Morphogenesis, August 7, Clemson, SC.

- Adam MP, Hennekam RC, Keppen LD, Bull MJ, Clericuzio CL, Burke LW, Guttmacher AE, Ormond KE and Hoyme HE: Marshall-Smith Syndrome: Natural history and evidence of an osteochondrodysplasia with connective tissue abnormalities. American Journal of Medical Genetics 137A:117–124, 2005.

- Baldellou Vazquez A, Ruiz-Echarri Zelaya MP, Loris Pablo C, Ferr#{225}ndez Longas A, Tamparillas Salvador M. El sIndrome de Marshall-Smith: a prop#{243}sito de una observad#{243}n personal. An Esp Pediatr 1983; 18:45-50.

- Butler, M.G. (2003). Marshall–Smith syndrome. In: The NORD Guide to Rare Disorders. (pp219–220) Lippincott, Williams & Wilkins, Philadelphia, PA.

- Charon A, Gillerot T, Van Maldergem L, Van Schaftingen MH, de Bont B, Koulischer L. The Marshall–Smith syndrome. Eur J Pediatr 1990; 150: 54-5.

- Dernedde, G., Pendeville, P., Veyckemans, F., Verellen, G. & Gillerot, Y. (1998). Anaesthetic management of a child with Marshall–Smith syndrome. Canadian Journal of Anesthesia. 45 (7): 660. Anaesthetic management of a child with Marshall-Smith syndrome

- Diab, M., Raff, M., Gunther, D.F. (2002). Osseous fragility in Marshall–Smith syndrome. Clinical Report: Osseous fragility in Marshall-Smith syndrome

- Ehresmann, T., Gillessen-Kaesbach G., Koenig R. (2005). Late diagnosis of Marshall Smith Syndrome (MSS). In: Medgen 17.

- Hassan M, Sutton T, Mage K, LimalJM, Rappaport R. The syndrome of accelerated bone maturation in the newborn infant with dysmorphism and congenital malformations: (the so-called Marshall–Smith syndrome). Pediatr Radiol 1976; 5:53-57.

- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. Western Society for Pediatric Research, Carmel, California, February, 1987. Clin Res 35:68A, 1987.

- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. David W. Smith Morphogenesis and Malformations Workshop. Greenville, SC, August, 1987. Proceedings of the Greenwood Genetics Center 7:152, 1988.

- Hoyme HE, Byers PH, Guttmacher AE: Marshall–Smith syndrome: Further evidence of an osteochondrodysplasia in long-term survivors. David W. Smith Morphogenesis and Malformations Workshop, Winston-Salem, NC, August, 1992. Proceedings of the Greenwood Genetic Center 12:70, 1993.

- .

- Tzu-Jou Wang (2002). Marshall–Smith syndrome in a Taiwanese patient with T-cell immunodeficiency. Am J Med Genet Part A;112 (1):107-108.

Overall, the prognosis for patients with NOMID is not good, though many (80%) live into adulthood, and a few appear to do relatively well. They are at risk for leukemia, infections, and some develop deposits of protein aggregated called amyloid, which can lead to kidney failure and other problems. The neurologic problems are most troubling. The finding that other diseases are related and a better understanding of where the disease comes from may lead to more effective treatments.

Several medications have been studied for the treatment of TNF receptor associated periodic syndrome including etanercept, and infliximab,

Cryopyrin-associated periodic syndrome (CAPS) is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin 1β-mediated systemic inflammation and clinical symptoms involving skin, joints, central nervous system, and eyes. It encompasses a spectrum of three clinically overlapping autoinflammatory syndromes including familial cold autoinflammatory syndrome (FCAS, formerly termed familial cold-induced urticaria), the Muckle–Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease (NOMID, also called chronic infantile neurologic cutaneous and articular syndrome or CINCA) that were originally thought to be distinct entities, but in fact share a single genetic mutation and pathogenic pathway.

It is not known how mevalonate kinase mutations cause the febrile episodes, although it is presumed that other products of the cholesterol biosynthesis pathyway, the prenylation chains (geranylgeraniol and farnesol) might play a role.

TNF receptor associated periodic syndrome is autosomal dominant, and about 70 mutations of the TNFRSF1A gene have been linked to this condition. Its cytogenetic location is at 12p13.31

Periodic fever syndromes (also known as autoinflammatory diseases or autoinflammatory syndromes) are a set of disorders characterized by recurrent episodes of systemic and organ-specific inflammation. Unlike autoimmune disorders such as systemic lupus erythematosus, in which the disease is caused by abnormalities of the adaptive immune system, patients with autoinflammatory diseases do not produce autoantibodies or antigen-specific T or B cells. Instead, the autoinflammatory diseases are characterized by errors in the innate immune system.

The syndromes are diverse, but tend to cause episodes of fever, joint pains, skin rashes, abdominal pains and may lead to chronic complications such as amyloidosis.

Most autoinflammatory diseases are genetic and present during childhood. The most common genetic autoinflammatory syndrome is familial Mediterranean fever, which causes short episodes of fever, abdominal pain, serositis, lasting less than 72 hours. It is caused by mutations in the MEFV gene, which codes for the protein pyrin.

Pyrin is a protein normally present in the inflammasome. The mutated pyrin protein is thought to cause inappropriate activation of the inflammasome, leading to release of the pro-inflammatory cytokine IL-1β. Most other autoinflammatory diseases also cause disease by inappropriate release of IL-1β. Thus, IL-1β has become a common therapeutic target, and medications such as anakinra, rilonacept, and canakinumab have revolutionized the treatment of autoinflammatory diseases.

However, there are some autoinflammatory diseases that are not known to have a clear genetic cause. This includes PFAPA, which is the most common autoinflammatory disease seen in children, characterized by episodes of fever, aphthous stomatitis, pharyngitis, and cervical adenitis. Other autoinflammatory diseases that do not have clear genetic causes include adult-onset Still's disease, systemic-onset juvenile idiopathic arthritis, Schnitzler syndrome, and chronic recurrent multifocal osteomyelitis. It is likely that these diseases are multifactorial, with genes that make people susceptible to these diseases, but they require an additional environmental factor to trigger the disease.

Another example that shows that autoinflamatory conditions may not be genetic in origin is found in a report published in "Nature" which shows that diet is very important in the development of such diseases. The ingestion levels of highly saturated fats and cholesterol, (high fat diet, HFD) affects the microbiota composition of the gut. Changes in the microbiota induced by a HFD are protective against the susceptibility to develop osteomyelitis (autoimmune disease) as compared with the changes induced by a low-fat diet. The changes in the microbiome of individuals under HFD showed a reduction in "Prevotella" abundance and were accompanied by significantly reduced expression levels of pro-Interleukin-1β in distant neutrophils.

Since interleukin 1β plays a central role in the pathogenesis of the disease, therapy typically targets this cytokine in the form of monoclonal antibodies (such as canakinumab), binding proteins/traps (such as rilonacept), or interleukin 1 receptor antagonists (such as anakinra). These therapies are generally effective in alleviating symptoms and substantially reducing levels of inflammatory indices. Case reports suggest that thalidomide and the anti-IL-6 receptor antibody tocilizumab may also be effective.

Virtually all people with the syndrome have mutations in the gene for mevalonate kinase, which is part of the HMG-CoA reductase pathway, an important cellular metabolic pathway. Indeed, similar fever attacks (but normal IgD) have been described in patients with mevalonic aciduria – an inborn error of metabolism now seen as a severe form of HIDS.

Familial dysautonomia is seen almost exclusively in Ashkenazi Jews and is inherited in an autosomal recessive fashion. Both parents must be carriers in order for a child to be affected. The carrier frequency in Jewish individuals of Eastern European (Ashkenazi) ancestry is about 1/30, while the carrier frequency in non-Jewish individuals is unknown. If both parents are carriers, there is a one in four, or 25%, chance with each pregnancy for an affected child. Genetic counseling and genetic testing is recommended for families who may be carriers of familial dysautonomia.

Worldwide, there have been approximately 600 diagnoses recorded since discovery of the disease, with approximately 350 of them still living.

CRMO was once considered strictly a childhood disease, but adults have been diagnosed with it. The affected tends to range from 4 to 14 years old, with 10 as the median age. As stated above, CRMO occurs 1:1,000,000 and primarily in girls with a 5:1 ratio. That means out of six million, there will probably be 5 girls and 1 boy with the condition.

Antihistamines are not effective in treating the hives in this condition. It may respond to immunosuppressant drugs such as corticosteroids, cyclooxygenase inhibitors, interferon alpha, interleukin 1 receptor antagonists (Anakinra), perfloxacin, colchicine, cyclosporine or thalidomide. The hives may respond to treatment with PUVA, and the bone pain may respond to bisphosphonates.

Because Schnitzler's syndrome is so rare, the efficacy of different treatments cannot be compared using statistics. Nevertheless, case studies provide evidence that anakinra (otherwise known as kineret) is much more effective for Schnitzler's syndrome than any other drug, and that the improvement in symptoms associated with this treatment is dramatic. For example, Beseda and Nossent (2010) reviewed the literature concerning IL1-RA treatment (i.e. anakinra) for Schnitzler's syndrome. They concluded that, “Twenty-four patients with Schnitzler's syndrome... have been successfully treated with anakinra.” They add that “seven out of seven patients [with Schnitzler’s syndrome], that either interrupted or used anakinra every other day, had relapse of their symptoms within 24-48 h; anakinra was restarted in all patients with the same clinical efficiency.” Kluger et al. (2008) investigated the effectiveness of anakinra for a range of conditions. They searched MEDLINE for English-language trials of anakinra and abstracts from rheumatologial scientific meetings. They conclude that, “Over the last few years it has become increasingly evident that anakinra is highly effective and safe in patients with ... Schnitzler’s syndrome”. The year before, De Koning et al. (2007) reviewed the disease characteristics of Schnitzler syndrome and collected follow-up information to gain insight into long-term prognosis and treatment efficacy. They used data from 94 patients, and their conclusions about treatment for the condition are that, “There have been promising developments in therapeutic options, especially antiinterleukin-1 treatment, which induced complete remission in all 8 patients treated so far.”

Reports of individual patients treated with anakinra illustrate its effectiveness. Beseda and Nossent (ibid.) report treating a longstanding multidrug resistant Schnitzler’s syndrome patient with anakinra: “Within 24 h after the first injection, both the urticaria and the fever disappeared and have not recurred. For the past 6 months, the patient has been in clinical and biochemical remission.” Other authors report “a complete resolution of symptoms” (Dybowski et al., 2008). Crouch et al. (2007) report the effective treatment of a 52-year-old man who had been diagnosed with Schnitzler’s syndrome 8 years earlier: “On review, one week later, the patient’s systemic symptoms had resolved, and his previously elevated white cell count and inflammatory markers had normalised. The use of anakinra in our patient resulted in resolution of symptoms and has enabled cessation of oral prednisolone. Our patient remains symptom free on anakinra after 14 months of follow-up”. Similar stories are reported by Frischmeyer-Guerrerio et al. (2008), Wastiaux et al. (2007), and Eiling et al. (2007), Schneider et al. (2007). De Koning et al. (2006) treated three patients with Schnitzler’s syndrome with thalidomide and anakinra. Thalidomide was only effective for one of the three patients and was discontinued because of polyneuropathy. In contrast, for all three patients, anakinra “led to disappearance of fever and skin lesions within 24 hours. After a follow-up of 16-18 months, all patients are free of symptoms”. The authors concluded that anakinra as a treatment for Schnitzler’s syndrome “is preferable to thalidomide... as it has fewer side effects”.

As well as being more effective, anakinra is safer than the other treatments available for Schnitzler's syndrome. The Cochrane review entitled, ‘Anakinra for rheumatoid arthritis’ (Mertens and Singh, 2009 ) evaluates the (clinical effectiveness and) safety of anakinra in adult patients with rheumatoid arthritis, using data from 2876 patients, from five trials which constituted 781 randomized to placebo and 2065 to anakinra. The authors conclude, “There were no statistically significant differences noted in most safety outcomes with treatment with anakinra versus placebo - including number of withdrawals, deaths, adverse events (total and serious), and infections (total and serious). Injection site reactions were significantly increased, occurring in 1235/1729 (71%) versus 204/729 (28%) of patients treated with anakinra versus placebo, respectively”. These injection site reactions last for no more than four months, and are trivial compared to the very debilitating symptoms of Schnitzler's syndrome.

Prognosis will depend on your child's individual disease and response to treatment. It is best to discuss the prognosis with your child's pediatric rheumatologist.

This condition is incredibly rare, with only 100 cases reported worldwide, however there are thought to be many cases that have been left undiagnosed. It is either inherited from at least one parent containing the mutated gene. or it can be gained through the mutation of the KCNJ2 gene.

A large British study from 2008 found a median estimated life expectancy of 11.6 years.

The outlook for patients with FD depends on the particular diagnostic category. Patients with chronic, progressive, generalized dysautonomia in the setting of central nervous system degeneration have a generally poor long-term prognosis. Death can occur from pneumonia, acute respiratory failure, or sudden cardiopulmonary arrest in such patients.

Parents and patients should generally be educated regarding daily eye care and early warning signs of corneal problems as well as the use of punctal cautery. This education has resulted in decreased corneal scarring and need for more aggressive surgical measures such as tarsorrhaphy, conjunctival flaps, and corneal transplants.

Andersen–Tawil syndrome, also called Andersen syndrome and Long QT syndrome 7, is a form of long QT syndrome. It is a rare genetic disorder, and is inherited in an autosomal dominant pattern and predisposes patients to cardiac arrhythmias. Jervell and Lange-Nielsen Syndrome is a similar disorder which is also associated with sensorineural hearing loss. It was first described by Ellen Damgaard Andersen.

FMF affects groups of people originating from around the Mediterranean Sea (hence its name). It is prominently present in the Armenians, Sephardi Jews (and, to a much lesser extent, Ashkenazi Jews), Cypriots and Arabs.

A survey of 10,000 American households revealed that the prevalence of diagnosed primary immunodeficiency approaches 1 in 1200. This figure does not take into account people with mild immune system defects who have not received a formal diagnosis.

Milder forms of primary immunodeficiency, such as selective immunoglobulin A deficiency, are fairly common, with random groups of people (such as otherwise healthy blood donors) having a rate of 1:600. Other disorders are distinctly more uncommon, with incidences between 1:100,000 and 1:2,000,000 being reported.

By definition, primary immune deficiencies are due to genetic causes. They may result from a single genetic defect, but most are multifactorial. They may be caused by recessive or dominant inheritance. Some are latent, and require a certain environmental trigger to become manifest, like the presence in the environment of a reactive allergen. Other problems become apparent due to aging of bodily and cellular maintenance processes.