Hereditary transthyretin amyloidosis (ATTRv-amyloidosis), also known as familial amyloidosis with polyneuropathy (FAP) or Skelleftesjukan, is an inherited disease that causes symptoms from, among other things, peripheral nerves, heart, stomach and intestines, eyes and kidneys.Amyloidosis means the deposition of insoluble protein complexes in the body's tissues, while polyneuropathy means impaired function in peripheral nerves, the nerves that do not belong to the brain and spinal cord.Symptoms begin in adulthood, usually as numbness and loss of feeling in the feet, lower legs and sometimes hands.Gradually, arm and leg muscles also weaken.Involuntary weight loss and problems from the stomach and intestines often appear early in the course of the disease.Disturbances in the heart rhythm (arrhythmias) are common and, over time, also heart failure.The kidneys are affected and in the long run kidney failure can occur.Some people get dry eyes and impaired vision.The disease has a progressive course with both faster and slower deterioration.There are today (2020) several drugs that can slow the progression of the disease, but they must be given at an early stage.Medicines are also used to treat symptoms such as nerve pain, heart failure, gastrointestinal symptoms, kidney failure and dry eyes.Arrhythmias may need to be treated with a pacemaker.During surgery and anaesthesia, it is important to pay attention to changes in the heart rhythm.Rehabilitation efforts may also be needed.Liver transplantation can in some cases stop the development of the disease and should then be done early.For some people, a heart transplant is also considered.The name amyloidosis comes from the Latin amylum, meaning starch, because it was first thought that it was sugars and not proteins that accumulated.The disease was first described in the medical literature by the German neuropathologist Friedrich Wohlwill in 1942.Hereditary transthyretin amyloidosis occurs all over the world but is more common in certain limited areas such as northern Sweden, northern Portugal, Brazil and Japan.That in Sweden it is called Skelleftesjukan is due to the fact that most people with the disease are found in the area of ​​Skellefteå and Piteå.It is estimated that the disease is found in 1–2 people per 100,000 inhabitants in the whole of Sweden, while the corresponding figure for Norrbotten and Västerbotten is around 50 per 100,000 inhabitants.This corresponds to a total of approximately 450 people in Sweden.Hereditary transthyretin amyloidosis is caused by a change (mutation) in the TTR gene on chromosome 18 (18q12.1) which is a template for the production of (codes for) the serum protein transthyretin (TTR).Transthyretin is produced mainly in the liver but also locally in the eye and the central nervous system (CNS) and normally helps with the transport of vitamin A and thyroid hormone in the blood.Mutations in the TTR gene cause the protein to change shape, fall apart and easily clump together into long protein threads (amyloid) which are stored in, among other things, peripheral nerves, the heart muscle, the vitreous body of the eye and the kidneys.In principle, the deposition can take place in all organs, but less often in the central nervous system.The protein threads can consist of two types of fibrils (thread-like structural elements): whole or cleaved fibrils.The fibril type is significant for variations in disease expression and the prognosis after liver transplantation.In Sweden, over 90 percent of everyone with the disease has the mutation c.148G>A(p.Val50Met), which causes the amino acid valine to be replaced by methionine in the transthyretin molecule (amino acids are the components that proteins are made of).The symptoms vary partly depending on which mutation you have, but the type of amyloid is also important.The mutation is inherited in an autosomal dominant manner.This means that if one of the parents has the disease, i.e. has a normal gene and an altered (mutated) gene, the probability for both sons and daughters to inherit the mutation is 50 percent.The children who have not received the mutated gene do not get the disease and do not pass it on.In the case of hereditary transthyretin amyloidosis, the impact (penetrance) is low and no more than about 20 percent of everyone who carries the mutation has developed the disease by the age of 60.The reason for this is still unknown.Autosomal dominant inheritance.The severity of the disease is not affected by whether one gets the mutation in a single or double set, i.e. from just one or from both parents.If you inherit the mutation from both of your parents, the risk of getting sick does not increase.You also do not get the disease at a younger age and the course is not affected.In contrast, those who inherited the mutation from their mother seem to become ill at slightly younger ages than those who inherited the mutation from their father.The time when the first symptoms appear varies from early adulthood to very late in life.In Sweden, the average age for the first symptoms is closer to 60 years, while in Portugal, Brazil and Japan it is 30–40 years.Without treatment, the average survival is between 9 and 13 years from the first symptom.The disease seems to have a slightly faster course if you get it at a young age.In some families, however, the development of the disease is slower, and there are those who live more than 20 years after symptoms appear.What this is due to is not yet clear.The first symptoms are usually numbness, tingling or pain from the feet (polyneuropathy).A common description is that it feels like walking on pillows.There are also those who initially experience erectile dysfunction, heart rhythm disturbances (arrhythmias), complaints from the stomach and intestines, egg whites in the urine (proteinuria) or involuntarily lose weight.Polyneuropathy is progressive and of the sensory-motor and autonomic type, which means that it affects both sensation and muscle function, as well as autonomic (non-volitionally controlled) nerve functions in the stomach, intestines and heart, as well as sexual ability.The problems often begin with a loss of sensation in the feet and gradually spread upwards.When the symptoms have reached the knees, one often also gets problems from the hands.For some, the sensory disturbance predominates, while others experience muscle weakness, but all of them experience a disturbance of both sensation and muscle function over time.Often a severe and cutting pain also occurs at some point during the course of the disease, which can be difficult to treat.In hereditary transthyretin amyloidosis, it is common to have sensory disturbances in the form of a lack of ability to experience heat and cold.It is not uncommon for people diagnosed with the disease to have previously sought treatment for burns.The loss of sensation can also mean that you do not feel pain in a normal way.The reduced sensation in the feet and legs often causes balance difficulties and falls easily.The nerve that controls the lower leg muscles that lift the foot (the peroneal nerve) is gradually damaged, causing drop foot which means difficulty in angling the foot upwards.This makes it easy to trip on carpets and thresholds, for example.The muscles in the feet, legs and hands gradually weaken, making it difficult to walk and grasp things.As the disease progresses, walking difficulties increase and become so great that many need to use a wheelchair when moving around.In parallel with polyneuropathy in the arms and legs, the autonomic nervous system is also affected, and in men, impotence is an early sign of this.Even women's sexual ability can be impaired by the disease and possibly a poorer function in the pelvic floor contributes to this.The first symptoms from the gastrointestinal tract are often constipation or an early feeling of fullness.Eventually the symptoms change to alternating constipation and diarrhea.Finally, uncontrollable diarrhea dominates, which together with nausea and vomiting leads to malnutrition and weight loss.The cause of the symptoms from the gastrointestinal tract is not fully understood, but amyloid deposition in the autonomic nervous system and in the gastrointestinal tract's own nervous system as well as disturbances in the stomach's neuroendocrine hormone system seem to contribute.The diarrhea can also be complicated by abnormal growth of certain intestinal bacteria and a lack of absorption of bile salts and fatty acids in the intestine.Many people with the disease get arrhythmias.All types of disturbances in the heart's conduction system occur, but atrial fibrillation is common, as is blockage of the electrical conduction between the heart's atria and ventricles (AV block), and many therefore require pacemakers.It is important to know that some people with the disease can have arrhythmias without other signs of heart disease.In people with cleaved amyloid fibrils, where the disease usually appears at age 50 or later, it is common for the heart muscle to be thickened (hypertrophic cardiomyopathy).The thickening is most evident in the septum between the heart chambers.The cardiomyopathy leads to a stiffer heart muscle with the result that the heart's filling and pumping ability deteriorates.Impaired heart function manifests itself as increased fatigue, reduced fitness, shortness of breath and accumulation of fluid in the body.Drops in blood pressure that cause dizziness, palpitations and sometimes fainting when standing up (orthostatic hypotension) are also common and often difficult to relieve with medication.This is due to impaired blood pressure regulation, which in turn can be caused by both the autonomic neuropathy and an affected heart function.An early sign of the disease can be the presence of egg whites in the urine (proteinuria).Due to disturbances in the nervous system, difficulties eventually arise in emptying the bladder, which can lead to urinary tract infections and incontinence problems.In women, dry mucous membranes in the vagina can further increase the risk of urinary tract infections.Late in the course of the disease, failing kidney function (uremia) can occur.Deposits of amyloid in the vitreous body of the eye occur and cause vision to deteriorate.Glaucoma is also more common in people with hereditary transthyretin amyloidosis than in others.Ulcers on the cornea of ​​the eye can occur due to dry mucous membranes.People with the disease often also have carpal tunnel syndrome 5–10 years before the diagnosis is established.Carpal tunnel syndrome involves pressure against the median nerve in the palm of the hand, leading to numbness in the thumb, index and middle fingers and weakness in some of the muscles of the thumb.Narrowings in the spinal canal (spinal stenosis) also occur in people with the disease.This is probably due to local deposition of amyloid.In the mouth, the dry mucous membranes can increase the risk of caries.Impaired adrenal function may occur.For some TTR mutations, central nervous system (CNS) symptoms are common.Most mutations seem to confer a long-term risk of CNS symptoms due to amyloid deposition in the brain's membranes and blood vessels, leading to an increased risk of stroke.This is especially true if atrial fibrillation is present at the same time.The diagnosis of hereditary transthyretin amyloidosis is suspected based on characteristic symptoms such as signs of polyneuropathy, arrhythmias, complaints from the gastrointestinal tract, involuntary weight loss and protein in the urine.Peripheral nerve function is investigated with various neurophysiological tests, such as electroneurography (ENeG), temperature sense tests and tests of autonomic nervous system function.Ultrasound or magnetic resonance imaging and scintigraphy of the heart can show signs of amyloid deposition and further strengthen the suspicion.To detect amyloid deposits, a biopsy is performed, which means that a small piece of tissue, usually from abdominal fat, intestinal lining or salivary gland, is examined under a microscope.Often, it is also possible to examine the type of protein that formed amyloid from the same sample.The diagnosis is confirmed by DNA analysis to detect TTR mutation.In connection with the diagnosis, it is important that the family is offered genetic guidance, which means information about the disease and how it is inherited.Assessment of the probability that others in the family will become ill is also included, as well as information on what possibilities for diagnostics are then available.If the mutation in the family is known, for many hereditary diseases there is the possibility of carrier and fetal diagnostics, as well as preimplantation genetic diagnostics (PGD) in connection with in vitro fertilization.If you have a parent with hereditary transthyretin amyloidosis, it is possible to investigate whether you carry the mutated gene or not (presymptomatic test).However, the testing does not provide answers as to whether or when the disease will appear or how the course of the disease will be.There are currently (2020) three approved drugs for the treatment of people with hereditary transthyretin amyloidosis, and drug therapy is now primarily used to slow the progression of the disease.Tafamidis works by stabilizing the transthyretin molecule, which reduces amyloid formation and slows down the course of the disease.However, studies have shown that amyloid formation cannot be stopped in all people with the disease.Tafamidis is approved for the treatment of people with early-stage neuropathy who do not use walking aids, and has later also been shown to have a disease-slowing effect in people with mild to moderate amyloid cardiomyopathy.The substances inotersen and patisiran work by reducing the liver's production of TTR at the gene level, which also reduces amyloid formation and slows down the course of the disease.Inotersen and patisiran are approved for the treatment of people with neuropathy who are not wheelchair users.None of the above drugs has any proven slowing effect on the local amyloid deposition that can occur in the eye and CNS.If the above approved drugs cannot be used, it is possible to apply for a license from the Swedish Medicines Agency for treatment with diflunisal, which also stabilizes the transthyretin molecule and slows down the course of the disease.Liver transplantation has also been shown to be able to stop the progression of the disease in some cases if it is performed at an early stage.The faulty transthyretin is formed for the most part in the liver, and a liver transplant causes the production of this to decrease by more than 95 percent.Liver transplantation has been performed since 1990 for hereditary transthyretin amyloidosis, and the long-term prognosis after a transplant is today (2020) good.However, many liver transplants are no longer performed because medical treatments are available and transplantation is not suitable for all people with hereditary transthyretin amyloidosis.A transplant is best suited for young patients with the Val50Met mutation who are early in the course of the disease and have no signs of heart involvement (cardiomyopathy).This is likely related to the amyloid fibril type.Deposits in the vitreous body of the eye and in the CNS are also not affected by the liver transplant, because the transthyretin that causes amyloid deposits in these organs is not formed in the liver but locally in the eye and in the CNS.People with cardiomyopathy are not helped by a liver transplant, unless a heart transplant is performed in parallel.Before a liver transplant, a comprehensive investigation is carried out, with careful examinations of all the organs that may be affected by the disease.Special emphasis is placed on heart examination, as heart function is of great importance for the result.The pains caused by polyneuropathy are usually difficult to treat with drugs.The drugs that work best are gabapentin, pregabalin, clonazepam and amitriptyline (tricyclic antidepressant), but sometimes morphine-like preparations are needed and of these methadone is often the most effective.Since many organ systems can be affected by the disease, it is important that the drug dosage is adjusted accordingly.Erectile dysfunction in men is treated with medication, but the treatment is made more difficult by the fact that it entails an increased risk of a drop in blood pressure.For women, among other things, pelvic floor training can improve sexual ability.To get help with questions about the diet, contact with a dietician is needed, preferably early in the course of the disease.Constipation can be treated with various medicines, but it is important to be aware that the disease causes constipation to turn into diarrhea after a while.Diarrhea can usually be treated initially with conventional medicines, but the treatment is often complicated by bacterial overgrowth in the small intestine and a lack of absorption of fat and bile salts in the small intestine.This sometimes requires treatment with antibiotics and/or bile salt binding drugs (cholestyramine).Reducing fat intake in the diet can also help with insufficient absorption of both fat and bile salts.If the diarrhea becomes very difficult to control, an operation in which a piece of the large intestine is placed forward and sewn to the abdomen (colostomy) can be of great help.Early satiety, nausea and vomiting may be due to slow gastric emptying.Then drugs that stimulate gastric emptying, such as metoclopramide and erythromycin, can have a temporary effect.A pacemaker may be relevant for various types of rhythm disturbances.There is an increased risk of a drop in blood pressure in case of possible anesthesia and operations of people with hereditary transthyretin amyloidosis.This may be due to cardiac arrhythmia, but also to impaired regulation of blood pressure due to autonomic neuropathy.Therefore, extra attention is required to heart rhythm and blood pressure during the procedure, and there should be preparedness to be able to insert a pacemaker if necessary.Heart failure is treated with drugs, but it is important to be aware that people with amyloid cardiomyopathy are often sensitive to drugs that lower heart rate and blood pressure.Such drugs are often used in heart failure from other causes, but have no safe effect in heart failure caused by amyloidosis.Therefore, diuretic drugs are a first choice for these people, for example loop diuretics and aldosterone antagonists.Atrial fibrillation carries a high risk of stroke in people with amyloidosis.Blood-thinning treatment (anticoagulation) is therefore given regardless of other risk factors, preferably in the form of direct-acting oral anticoagulants (DOACs), which carry a slightly lower risk of cerebral haemorrhage.Support stockings can to some extent counteract a drop in blood pressure.In case of adrenal insufficiency, treating it can reduce the risk of a drop in blood pressure.Difficulty emptying the bladder can be reduced with exercise.The next treatment step is pure intermittent catheterization (RIK), which means emptying the bladder yourself regularly with a catheter that is removed after each use.If this does not work, a permanent catheter may be required, which means that the urine is led from the bladder via a tube to a bag which is then emptied when necessary.A catheter through the abdominal wall (suprapubic catheter) can sometimes be an option.Kidney failure is treated with medication and diet.Because kidney failure in hereditary transthyretin amyloidosis occurs late in the course of the disease, it is unusual for dialysis treatment to be needed.The other symptoms are then often so serious that it is difficult to cope with the dialysis treatment.If kidney function is impaired at the time of a possible liver transplant, a kidney transplant is sometimes performed at the same time.The reason for this is that the anti-rejection treatment given during the liver transplant causes the kidney function to further deteriorate.If there is deposition of amyloid in the vitreous, it can be surgically removed.Glaucoma is treated with drugs that lower the pressure in the eyes and sometimes with surgery.Cortisone treatment given after liver transplantation can lead to the development of cataracts.It is also treated with surgery.For dry eyes, there are tear substitutes and corneal ulcers can be treated with local antibiotics.Failing adrenal cortex function is investigated and treated according to the routines that exist for this condition (see Addison's disease).To prevent caries, it is important to have regular contact with a dentist and dental hygienist, as well as to use medicines that increase saliva production in the early stages of the disease.Carpal tunnel syndrome and spinal stenosis are operated upon if necessary.There is no specific treatment for CNS complications, but it is important to treat with stroke prevention drugs (anticoagulants) if atrial fibrillation is detected and the risk of cerebral hemorrhage is not considered high.People with the disease need rehabilitation efforts from a cross-professional team with special knowledge of primarily neurological impairments and their effects on everyday life and health.The team provides support and treatment in the medical, psychological, social and technical fields.The efforts consist of, among other things, investigation, treatment, testing of aids, information about the disability and conversational support.They also include information about the community support that is available as well as advice on adapting the home and other environments that one lives in. The interventions are planned based on the needs that exist and vary over time.As it is important to try to maintain the motor function of the musculature that is not affected by the disease as long as possible, regular physiotherapy is needed.Drop foot is countered with a specially designed orthosis that makes walking easier.The municipality can offer support in various forms to facilitate everyday life.It is important to continuously offer psychological support to people with the disease and their relatives.Research at an international level is conducted at several departments within Umeå University and at the Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University.Treatment studies with drugs whose purpose is to stabilize the transthyretin tetramer and thus prevent amyloid formation are ongoing.For the drug tafamidis, the trials have been completed regarding the effect on polyneuropathy, while a follow-up international long-term study is ongoing regarding the effect and safety in the treatment of amyloid cardiomyopathy.The drug diflunisal has in studies shown equivalent results to tafamidis for the treatment of polyneuropathy, but diflunisal is not registered as a drug in Sweden.Since 2015, an open Swedish treatment study has been ongoing that evaluates the effect of two years of treatment with diflunisal for patients with amyloid cardiomyopathy.Studies with the substance tolcapone are also ongoing and early results have shown that it has a good stabilizing effect on transthyretin, and that tolcapone passes over the blood-brain barrier, which suggests that it may also have an effect on amyloid deposition in the CNS and the eye.The substance AG10 has also been shown to be a potent stabilizer of transthyretin, and studies are underway to evaluate the efficacy and safety of AG10 in the treatment of amyloid cardiomyopathy and polyneuropathy.Trials are ongoing with drugs whose purpose is to reduce the liver's production of both normal and mutated transthyretin (gene therapy) at the gene level and thereby stop the course of the disease.Both trials with new variants of gene therapy and studies of the long-term effects of existing drugs (inotersen and patisiran) are ongoing.Antibodies against transthyretin are also being investigated as a future treatment option, but this is still at an early stage.The hope is that treatment with new drugs, which partly prevent amyloid from forming and partly dissolve already formed amyloid, will be able to become effective treatment options for all people with the disease in the future.THAOS (Transthyretin Amyloidosis Outcomes Survey) is an international database that collects information on the course of transthyretin amyloidosis.A national quality register for transthyretin amyloidosis (SveATTR), see regionvasterbotten.se/sveattr, was established in autumn 2020 to promote a high and consistent quality of care for people with transthyretin amyloidosis in Sweden and to facilitate clinical research.The European database Orphanet collects information on research related to rare health conditions, see orpha.net, search terms: ATTRV30M amyloidosis, transthyretin amyloid neuropathy.DNA-based diagnostics are performed in the clinical genetics departments at the university hospitals.Treatment at the regional level is offered at:Medical center, Norrland University Hospital, Umeå, telephone 090-785 00 00.Medicine-geriatric clinic, Skellefteå hospital, Skellefteå, telephone 0910-77 10 00.Medical and rehabilitation clinic, Piteå älvdals hospital, Piteå, telephone 0911-750 00.Treatment and rehabilitation at regional and national level is offered at the Neuro-head-hals centre, Neurorehab Sävar, Sävar, telephone 090-785 98 50.Investigation at national level, with a focus on diagnostics and investigations before both medical treatment and liver transplantation, is offered at the Medical and Heart Centre, Norrlands University Hospital, Umeå, telephone 090-785 00 00.Reception Neuro, ME Neurology, Karolinska University Hospital, Huddinge, telephone 08-585 800 00.Liver transplants are performed at the transplant surgery clinics at Karolinska University Hospital, Huddinge, in Stockholm and at Sahlgrenska University Hospital in Gothenburg.Centers for rare diagnoses (CSD) are located at all university hospitals.The CSD welcomes questions and can provide guidance and information on rare health conditions.Contact details for CSD in each region can be found on the joint website CSD in collaboration, see csdsamverkan.se.The website also contains information about expert teams for various diagnoses and diagnostic groups, as well as links to other sources of information.The European Reference Network (ERN) brings together doctors and researchers who are experts in rare diseases and conditions.In the virtual networks, diagnosis and treatment are discussed for patients from all over Europe.For more information, see the European Commission and Orphanet.Hereditary transthyretin amyloidosis is included in the ERN EURO-NMD for neuromuscular diseases.The resource persons can answer questions about hereditary transthyretin amyloidosis.Amyloidosis Centre, Norrlands University Hospital, Umeå, telephone 090-785 39 59, e-mail amyloidoscentrum@regionvasterbotten.se.Contact persons are chief physician Jonas Wixner, chief physician (cardiologist) Björn Pilebro, nurse Lina Wiss, nurse/genetic counselor Hans-Erik Lundgren and study nurses Rolf Backlund, Ulrika Englund and Malin Falk.The FAP team at the medicine-geriatric clinic, Skellefteå lasarett, Skellefteå, telephone 0910-77 11 38. Contact persons are chief physician Erik Wallmark and nurses Elisabeth Stenberg and Britt-Marie Nilsson.The FAP team at Piteå Älvdal Hospital, Piteå, telephone 0911-755 43. Contact persons are chief physician Katarzyna Liszewska and specialist physician Jorge Mejia Baranda and nurses Anna-Lena Lundberg and Martina Björk.Professor, chief physician Bo-Göran Ericzon, Transplantation Surgery Clinic, Karolinska University Hospital, Huddinge, telephone 08-585 876 ​​66, e-mail bo-goran.ericzon@ki.se.Professor, senior physician Michael Olausson, Transplantation Center, Sahlgrenska University Hospital, Gothenburg, telephone 031-342 10 00, e-mail michael.olausson@surgery.gu.se.With dr, associate chief physician Kristin Samuelsson, Reception Neuro, NE Neurology, Karolinska University Hospital, Huddinge, telephone 08-585 800 00, e-mail kristin.samuelsson@regionstockholm.se.Professor emeritus Per Westermark, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, telephone 0703-66 93 58, e-mail per.westermark@igp.uu.se.Many interest organizations can help mediate contact with others who have the same diagnosis and their relatives.Sometimes they can also provide other information, such as practical tips for everyday life, as well as convey personal experiences about what it can be like to live with a rare health condition.The interest organizations also often work with issues that can improve the conditions for the members, including by influencing decision-makers in various areas of society.FAMY Västerbotten, the Association against Familial Amyloidosis with Polyneuropathy, Skellefteå, telephone 0910-360 17, e-mail info@famy.se, famy.se.FAMY – Norrbotten, Piteå, telephone 0911-197 64, 072-250 97 64, e-mail famynorrbotten@outlook.com, famynorrbotten.se.Riksförbundet Rare diagnoses works for people living with rare diagnoses and various disabilities, telephone 072‑722 18 34, e‑mail info@sallsyntadiagnoser.se, sallsyntadiagnoser.se.For many rare health conditions, there are social media groups where you can communicate with others who have the same diagnosis and with parents and other relatives of people with the disease or syndrome.The database Orphanet collects information on interest organizations, especially in Europe, see orphan.net, search term: transthyretin amyloid polyneuropathy.The Center for Rare Diagnoses in Collaboration (CSD in Collaboration) has a calendar on its website, with current courses, seminars and conferences in the field of rare health conditions, see csdsamverkan.se.FAMY (The Association against Familial Amyloidosis with Polyneuropathy) organizes lectures and conferences for people with the disease and their relatives as well as for staff.For more information contact FAMY Västerbotten or FAMY - Norrbotten, see under the heading Interest organisations.For several of the diagnosis texts in the National Board of Health and Welfare's knowledge database on rare health conditions, there is a short summary in pdf format that can be downloaded, printed and used in various contexts.The summary can be found at the top of each page.Children, young people and adults with disabilities can receive different types of support and interventions from society.For more information, see Community support efforts.The brochure What You Should Know About Hereditary Transthyretin Amyloidosis with Polyneuropathy (hATTR) "Skellefte Disease" can be obtained free of charge from the patient associations FAMY Västerbotten and FAMY - Norrbotten (see under the heading Interest organisations).Personal stories about what it's like to live with a rare health condition and a lot of other information can often be found on the websites of interest organizations (see under the heading Interest organizations).Ågrenska's website also has personal stories and films as well as other valuable information, see agrenska.se.OMIM (Online Mendelian Inheritance in Man) omim.org Keyword: transthyretin