Spontaneous Chronic Urticaria: what causes it, treatment, photos

Spontaneous chronic urticaria (ECU) was formerly called idiopathic chronic urticaria.

It is an autoimmune disease that can affect people at any age, but it has a higher incidence in the age group of 20 to 40 years.

Because it causes several symptoms on the skin, this is a disease that also affects patients’ self-esteem .

Unfortunately, the ECU is still quite unknown to those who have the condition.

This is one of the reasons responsible for about 67% of patients giving up looking for a diagnosis.

On the other hand, it is known that 92% of patients who had the proper diagnosis and treatment are able to live without symptoms of the disease and with quality of life.


What is spontaneous chronic urticaria?

Spontaneous chronic urticaria (ECU) is an autoimmune disease. In it, patients have symptoms such as reddish patches on the skin, itching and, in some cases, swelling.

What characterizes a hives as a spontaneous chronic is its occurrence for more than 6 weeks and the fact that it does not have a known cause.

When it comes to chronic urticaria that has a known external cause, it has the classification of induced chronic urticaria.

The term “spontaneous” is present in ECU precisely to differentiate these two chronic forms of the disease.

ECU is an incurable disease, but it has spontaneous remission. As it manifests in patients, it goes away.

However, when this will happen is uncertain. Remission varies for each patient.

From diagnosis to remission, the patient with spontaneous chronic urticaria can count on treatments that allow the control of the disease.

In 92% of cases, patients become asymptomatic with appropriate treatment.

The complications caused by the ECU, in this way, interfere more in issues such as self-esteem, social interaction and even in the financial life, as many patients fail to go to work due to crises.

What is chronic idiopathic urticaria?

The term idiopathic is used in medicine to determine that a disease has an unknown cause or that its onset is spontaneous.

In the past, the term idiopathic chronic urticaria was used more. However, after discovering that many of the cases of ECU are of autoimmune origin, the term idiopathic has fallen out of use.

Although many others are of unknown cause and have no clear relationship to an immunological issue, the UCE nomenclature remains for most patients.

What are wheals?

Wheals, the main symptom of urticaria, are lesions that manifest on the patient’s skin, varying in size and area. These changes have a certain relief and a more reddish border.

The most common is that doctors refer to the symptom as wheals, but it is also possible to use the names of papules, welts or simply hives.

In addition to interfering aesthetically in the lives of people affected by the disease, they also cause a lot of itching.

This itchiness can be so intense that, for some patients, it ends up affecting several areas of their lives.

This can range from an interrupted sleep to the difficulty of studying, working or going out with friends or partners.

A specific feature of wheals is the fact that they stay for at least 24 hours in the same location on the patient’s body and then appear in other areas.

This duration, however, may vary for each patient, and may remain for a few hours only.

There are some variations of this symptom, they are:


The wheals can have different sizes, ranging from small (a few millimeters) or large (a few centimeters).


They may appear as red, pink spots or even with a more reddish border and a whitish center.

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Wheals can appear as circular spots or of any shape. There is not exactly a pattern.


ECU patients can suffer from wheals anywhere on their bodies, from the feet to the face.

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The wheals can appear only as a small outbreak, reaching a small area or manifest as a more intense attack, covering a large region of the skin.

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Causes of UCE disease

Spontaneous chronic urticaria is an autoimmune disease with no specific cause . As its name suggests, this disease appears to patients unexpectedly and without an external triggering agent.

In other types of urticaria, it is common to have factors such as food, plants, cold, etc.

However, at the ECU, none of these reasons are associated.

As in other autoimmune diseases , this pathology happens because the patient’s immune system understands that it needs to react against any allergen.

For this, in the case of spontaneous chronic urticaria, activates histamines.

Histamines are substances naturally produced by our body and are involved in several allergic processes. They have a vasodilating action as an immune response.

As a consequence, this excess of histamine produced ends up resulting in several reactions, such as the appearance of redness, itching and edema on the skin.

In the case of ECU, it ends up causing wheals, itching, swelling and other symptoms.

What, in fact, causes this activation of mast cells and the release of histamine is still unknown.

Some hypotheses suggest that this can happen because our organism, due to some failure, is unable to recognize a natural protein in the bloodstream and therefore releases histamines as a defense.

In addition to an immune response, causes such as an infection or allergic reactions to drugs such as anti-inflammatory drugs and painkillers are considered.

However, there is no consensus on these assumptions.

Between 40% to 45% of patients with ECU have a clearer connection with autoimmunity, which defines them as a more severe condition.

For other patients who do not have an autoimmune relationship as a cause, little is known about the development of the disease.

Is spontaneous chronic urticaria an allergy?

An allergy has a trigger and the ECU does not. As it does not contain a triggering factor, this disease is not considered an allergy .

Comparing an ECU with an allergy is understandable when we understand how the symptoms manifest themselves. Just as in a chronic urticaria, during an allergy, mast cells release the substance histamine and from there the characteristic symptoms appear.

In some cases, patients with some type of allergy may experience the formation of wheals as a symptom.

Thus, the main difference between an ECU and an allergy is the fact that in an ECU the patient cannot avoid the triggering factor, as it does not exist.

For example, people who are allergic to cat or dog fur are able to identify this trigger and avoid contact.

Groups of risk

Spontaneous chronic urticaria is a disease that can occur in any age group and in all people, in general.

However, it is uncommon in children and is more frequent in women aged 20 to 40 years.

The estimate is that spontaneous chronic urticaria affects 0.5% to 1% of the population, where women are the most affected, being twice as likely to manifest the disease as men.

Symptoms of spontaneous chronic urticaria

The main symptom of chronic spontaneous urticaria is the appearance of wheals.

These are higher patches with red edges that appear on the patient’s skin.

Other symptoms such as itching, burning sensation and, in some patients, swelling may also occur. Understand:


Itching, also called itching, is a symptom caused by an unusual activation of the immune system.

It is the excess histamines that cause the skin nerves that itchiness that is very uncomfortable and intense for patients.

The symptom can affect the patient’s routine, especially in his quality of life. Itching is one of the reasons for sleepless nights in patients with ECU.

Burning and burning sensation

As a complication of wheals and itching itself, patients with chronic spontaneous urticaria may also suffer from a burning sensation and burning skin.

These symptoms can vary in time and intensity depending on the case of each patient.


Angioedema is a symptom that is often confused with urticaria itself.

Basically, angioedema is a swelling that affects the deeper layers of the skin. This swelling also causes itching, pain and redness of the skin.

It does not happen in all cases of ECU and is therefore not considered a major symptom.

These swellings can happen in different parts of the body, being more common in the face (eyelids and lips), in the hands, feet and genital region.

When swelling of the tongue and throat occurs, it can lead the patient to difficulty breathing, which is life-threatening.

This symptom can last for more than 24 hours. Swelling is present in 50% of urticaria cases.

Despite being a common symptom in people with ECU, angioedema can also affect people who do not have some type of urticaria.

Glottis edema

Although it is not a frequent symptom, it is considered a warning sign in the context of ECU or other types of urticaria.

The edema of the glottis is a complication caused by a swelling of the glottis, structure of our body located at the end of the larynx.

This structure is responsible for preventing the passage of food to the respiratory system and also has the role of facilitating the entry and exit of air to the lungs.

The swelling of the glottis prevents this from happening and that is why it is considered an alert, as the patient, having his private breathing capacity, may suffer complications and even have his life at risk.

Is spontaneous chronic urticaria transmissible?

Spontaneous chronic urticaria or other types of urticaria are not transmissible. Therefore, being next to someone or having direct contact with wheals does not represent a risk of getting the disease, as it is not contagious .

Diagnosis: who is the specialist in chronic urticaria?

The diagnosis of ECU can be a long process.

The problem is often treated as a common allergy and misdiagnosed.

Thus, patients end up frustrated and unable to discover what, in fact, is causing all these reactions on the skin.

In other types of urticaria, however, the path to a correct diagnosis becomes less painful because it has a specific cause.

What makes diagnosis a challenge is precisely the fact that this disease does not have a specific cause.

Thus, the patient needs to follow some steps to get an adequate diagnosis, without having to wait for years to start the treatment.

First, when noticing the appearance of wheals or any of the symptoms, the patient should seek help from a dermatologist .

It is common for patients and even doctors to believe that the symptoms are of an allergy or an acute urticaria.

Therefore, patients can also be referred to an allergist doctor .


In the case of patients with ECU, it is unnecessary to request tests to check for a possible allergy.

However, these tests can help the doctor rule out this hypothesis, since urticaria is only considered chronic after 6 weeks .

From that, the doctor must evaluate some factors:

Patient history

To reach the diagnosis, the doctor needs to make a survey of the patient’s history regarding the disease and symptoms.

To do this, you must request the time of onset of the disease and analyze the frequency and duration of the injuries, which requires more detailed monitoring.

Other factors to be relieved include:

  • Identify whether the lesions caused by urticaria occur simultaneously with other allergies, infections or insect bites;
  • Identify whether heat or cold interferes with the appearance of lesions, as well as the use of medication or food.

Physical exams

With the patient’s history in hand, the doctor can proceed with the physical exams.

Basically, the doctor should make an assessment of the symptoms of hives.

For this, you can perform a test on the patient’s skin. The objective is to confirm that the urticaria did not occur due to the induction of a specific agent.

This fact could open the hypothesis of being a chronic induced urticaria, in the case of a patient who presents the symptoms for more than 6 weeks.

With the test result to check if there is an inducing agent, the doctor will be able to refer the patient to carry out complementary exams.

Complementary exams

Complementary tests can be done when the patient has other illnesses along with the symptoms of urticaria.

It is not a standard procedure to refer patients who suspect they have ECU for allergy tests.

The patient may also need to perform blood tests, so that it is possible to investigate whether there is any type of health impairment and that it is associated with the type of urticaria manifested.

Tests to check for thyroid function can be done.

There are cases of patients with Hashimoto ‘s thyroiditis, also an autoimmune disease, in which the symptoms are similar to those of a chronic urticaria.

The examination, in this case, helps to rule out this hypothesis.

Is chronic urticaria curable?

Spontaneous chronic urticaria is a disease that has no cure , but that has spontaneous remission . This means that at some point the disease “goes away”.

There is no standard time frame for this to occur.

During the period between diagnosis and remission, the patient must follow treatments to control the symptoms of the disease and live with quality of life.

The data regarding the conditions in which people with ECU live are positive. About 92% of patients become asymptomatic with appropriate treatment.

Thus, even if they are in a condition just to control the disease, patients can live without any symptoms.

Treatment of autoimmune urticaria

The treatment of ECU is done through medication and aims to make the patient asymptomatic until complete remission of the disease occurs .

It can be performed in 4 stages, ranging from the first to the fourth line.

If the first stage of treatment is able to eliminate the symptoms, the patient does not need to continue with the next ones, as it is a gradual treatment.

Treatment in pregnant or lactating women should be done with greater care.

Still in the diagnosis, it is necessary to eliminate the chances of the symptoms not belonging to other conditions that may arise in this phase.

This is because diseases such as gestational cholestasis, dermatitis and other conditions also cause itching and blemishes on the skin.

The doctor should talk to the pregnant women about the possible risks of treatment and follow up on the case.

In cases of ECU, in general, the treatment works as follows:

First line

The standard initial treatment for spontaneous chronic urticaria is performed with the use of non-sedating antihistamines, included in the 2nd generation category. These are first-line drugs.

They work to reduce the time of attacks, help to reduce the size of hives, swelling and itching.

There are also 1st generation antihistamines, which have more side effects, with possible impacts on the central nervous system.

The recommendation of the global guideline for the treatment of urticaria is that the use of these drugs should be avoided, especially in children.

Second line

Second-line pharmacological treatment is used in patients who have not responded well with first-line treatment.

It is also performed with the use of antihistamines, but this time the dosages used are higher.

In this second stage, the use of oral corticosteroids is also a possibility. However, they are indicated as an option for the control of more intense crises and should be used for a short term.

The corticosteroids introduced to the treatment act as anti-inflammatory and immunosuppressive agents.

Third row

The third step of an ECU treatment is also done with the use of medications, but in this case the patient is instructed to start using immunosuppressants.

This treatment is only indicated when the patient has not had good responses to previous treatments and should only be done with the accompaniment of a doctor.

The last stage ends up causing greater results for patients who have a severe and persistent condition of chronic spontaneous urticaria.

However, this treatment should not be done as a first option.

The consensus, until then, is that the patient starts treatment following the steps in that order.

Fourth row

The fourth line treatment is usually started when, even after 6 months of the third line treatment, the patient still does not show complete improvement of the symptoms.

If, in the patient’s evaluation, the doctor understands that the symptoms are controlled with the previous treatment, it is not necessary to proceed to the latter type of drug therapy.

Fourth-line treatment is usually done with the use of immunosuppressants that slow the body’s immune response and cease the skin hyperactivity responsible for the characteristic symptoms of urticaria.

Remedies for chronic urticaria

Medicines are the main form of treatment at the ECU. They are divided into three main types:

  • Antihistamines;
  • Corticoids;
  • Immunosuppressants.

2nd generation antihistamines are the most used in the treatment of chronic, spontaneous or induced urticaria. They reduce symptoms by interfering with the action of histamine under the patient’s body.

They are administered according to the treatment stage.

When the patient is unable to achieve symptom control in first-line treatment, doses of antihistamines are high.

The use of corticosteroids should be evaluated by a doctor .

The global guideline recommends that these drugs be used for short periods, of a maximum of 10 days, in order to reduce the progression of the disease.

Among the options of first and second line medications are:

  • Fexofenadine ;
  • Desloratadine ;
  • Levocetirizine ;
  • Loratadine .

In third-line treatment , the patient is instructed to follow treatment with Omalizumab , an anti-Ige monoclonal antibody that helps to block the body’s autoimmune action and prevent the release of histamine.

When it is necessary for the patient to continue with fourth-line treatment, treatment is done with cyclosporine , an immunosuppressive medication.


NEVER self-medicate or stop using a medication without first consulting a doctor. Only he will be able to tell which medication, dosage and duration of treatment is the most suitable for his specific case. The information contained in this website is only intended to inform, not in any way intended to replace the guidance of a specialist or serve as a recommendation for any type of treatment. Always follow the instructions on the package insert and, if symptoms persist, seek medical or pharmaceutical advice.

Living together

It is possible to live with the UCE and maintain a better quality of life. It will not always be easy and this can vary for each patient and severity of the condition.

However, there are ways to live with spontaneous chronic urticaria, while still carrying out your day-to-day activities and not having your relationship with other affected people.

Search for information

For patients or people close to someone who has been diagnosed, seeking information is an important step to be able to live with the ECU.

Knowing how the disease happens, understanding the symptoms and treatments can help reduce anxiety and be positive towards accepting the condition.

Knowing reports from other people who have the same condition as yours can help you live healthier with the disease and maintain treatment without frustration or anxiety while waiting for remission.

The internet and social networks can be useful tools at this time. Some patients provide information and experiences about their daily lives with spontaneous chronic urticaria, as is the case with the 3000 days channel .

In a series of videos, Valéria Rezende, diagnosed with ECU, tells about her daily life with the disease:

Follow up your painting

Monitoring the symptoms and the evolution of the disease can lead the patient to a greater knowledge about it. In addition, it contributes to the treatment being carried out according to your needs.

To carry out this monitoring, the carrier can use specific tables such as the Dermatology Quality of Life Index , for example.

Another scheme used is the UCE activity scoring system (UAS7). It is simple and should be done daily to note the changes and evolution of the symptoms of the disease.

It is a more complete and effective way of monitoring urticaria and it also helps doctors to analyze on which days and situations the disease improves or worsens.

In the table, the patient should write down, according to the level, what happened that day according to the symptoms.

For example, in the case of wheals, the patient must register if they did not appear (0 points), if they manifested lightly (1 point), if they manifested moderately (2 points) or seriously (3 points).

With itching, punctuation is done in the same way. From 0 to 3 points, ranging from no itch to severe itch. Thus, the score of this monitoring system varies from 0 to 6, daily.

It is recommended that the patient does this monitoring routinely for at least 7 days in a row.

The sum of the scores, in this period, will vary from 0 to 42 points and from that the doctor will evaluate the evolution of the disease.

Prioritize your quality of life

During treatment, the patient should be advised to follow a normal life.

Maintaining common day-to-day activities, such as going to work, studying, going out with friends and other commitments, should be kept, as far as possible.

The support of friends and family, at this time, also becomes essential.

People with ECU can suffer complications much more related to their emotional state and therefore may need the support of professionals, such as a psychologist.

To maintain a quality of life, it is recommended that the patient avoid situations of stress .

Do not freak out

Living with a chronic illness requires a little more patience. It is normal for patients to suffer from the diagnosis or the lack of it, since it is not so simple to discover that it is an ECU.

However, it is also necessary to understand that this desperation for diagnosis or cure does not make living with the disease more peaceful.

On the contrary, this feeling can make the patient even more frustrated.

Certainly, this impatience or anguish felt reflects negatively on the patient’s daily life and may end up interfering with symptoms or causing other complications.

Therefore, it is important that the patient seeks to perform activities that do him good, keep in touch with loved ones and try to continue attending his appointments.

Psychological counseling can also be beneficial at this time.

Follow medical recommendations

The patient must follow medical guidelines correctly in relation to medications and return to the office. The self-medication should never be done .

Practice physical activities

Doing physical activities is important for anyone. For patients with ECU, the practice of some sport or activity can make them feel more stimulated and with a better quality of life.

For some patients with severe conditions, some activities can be limiting. It is important to talk to the doctor about a possible fit.

Make compresses

The use of ice packs can help to reduce itching. It is a simple alternative to relieve one of the most uncomfortable symptoms of ECU.

Wear comfortable clothes

Some patients may feel that their symptoms get worse when it is hotter. Wearing comfortable, cool clothing can help you feel more relaxed and cooler.

Tight clothes can also make everyday life more uncomfortable, as they can put more pressure on wheals and possible swelling.

Invest in makeup and clothes to your advantage

Makeup and the use of clothes that can hide the wheals can help in this process of acceptance of the disease, since they contribute to disguise the symptoms.


ECU, although it is a little discussed disease, is the most common type of chronic urticaria.

The numbers about this pathology reveal that there is a lack of information about what it really is to live with the problem.

A survey conducted by the Ipsos Institute showed that 91% of Brazilians are unaware of what the disease is.

However, despite this percentage, it is not as rare as is thought. The research showed that the ECU affects more than 1 million people in Brazil.

Despite being a significant number of people affected by the disease, the main complications assessed are associated with the social impact on their lives.

With the advancement of research and the treatment carried out in stages, it is known that in 92% of cases of ECU patients are able to live without the symptoms of the disease and with a higher quality of life.

In the most severe cases of spontaneous chronic urticaria, the patient still needs greater support to be able to deal with the symptoms without having his sleep, work, self-esteem and personal life affected.

Although the length of stay at the ECU is uncertain, patients can count on treatment until the spontaneous remission of the disease occurs.


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Complications are more associated with the patient’s emotional factors than physical signs.

Although symptoms such as angioedema and glottis edema are a possibility, they are less common than the psychological effects suffered by the patient.

Diseases that affect the skin, as are the different types of urticaria, end up projecting problems of social interactions, because many times the patients are unable to accept the wheals nor to hide them.

Thus, they end up suffering with low self-esteem and little security about their own body. When in more exposed areas, such as the face, this can become even worse.

Some of the complications associated with these factors are:

Sleep deprivation

For many patients with ECU, sleeping becomes a difficult task. Not only because of the emotional factors involved, but also because of the symptoms like swelling and itching, which become extremely uncomfortable.

Shattered self-esteem

Insecurity with their own image is listed as one of the main complications that the ECU can bring to the lives of patients.

Apparent symptoms such as swelling and spots (wheals) end up significantly interfering with the appearance of patients. This can make them ashamed or afraid to even leave the house.

Depression and anxiety

Receiving the diagnosis of a disease such as ECU, which has no obvious cause and does not have a definite deadline for remission, is not easy.

Studies carried out on the impact of the disease on the quality of life of patients refer to the possibility of depression and anxiety together.

Social isolation

Social isolation is a complication that is associated with all other possibilities. ECU patients may feel less motivated, especially during crises, to participate in their daily activities.

The fact that the disease is little known intensifies this complication, as many people unaware of the patient’s situation may think it is contagious.

How to prevent ECU?

Unfortunately, spontaneous chronic urticaria is not a preventable disease, since it does not have a specific cause.

Because it is an autoimmune disease without a clear trigger, the patient is taken by surprise.

In such cases, the bearer should keep in mind that the ECU did not happen for something he did or did not do and did not blame the disease.

After diagnosis, what should be done is an appropriate treatment and a search for a quality of life, so as not to let the disease negatively affect your daily life.

Frequently asked questions about UCE

ECU is a disease that remains unclear and that is why there are some myths in its relationship. Check out what is true or common sense:

Who has hives can wear makeup?

Yes, patients who have some type of urticaria can wear makeup, this includes cases of chronic urticaria. Each case must be evaluated in isolation, but in general there are no restrictions.

In the case of the ECU, for example, external factors have no connection with the onset of symptoms.

Therefore, the use of makeup does not interfere with the onset or intensity of the disease .

The only restriction on the use of makeup happens in cases of contact urticaria, as this is a specific and allergic urticaria.

It happens as an immediate response to some substance and the symptoms manifest in a short time after this contact, ranging from a few minutes to 1 hour.

In this case, the patient must have greater knowledge about his type of hives and what may or may not cause the symptoms.

In the case of makeup, when you notice any reaction, you should stop using it and seek medical help.

Is chronic spontaneous urticaria a hereditary disease?

No . According to the scientific knowledge obtained so far, what is known is that ECU is not a disease that is passed on from generation to generation.

Thus, people with chronic spontaneous urticaria do not have to worry about whether their children will have this disease. This is because the chances of occurrence are equal in any person.

Can the patient’s stress or depression condition worsen the symptoms of urticaria?

The onset of a crisis may be related to some emotional factor. Stress, for example, provides vasodilation of the organism.

This vasodilation can cause a rise in body temperature and ends up intensifying some types of hives.

The patient’s emotional situation may be associated with the onset of the disease or contribute to its manifestation.

But this is not a standard.

It does not happen in the same way in all patients and in all types of hives.

At the ECU, there is no study that proves this direct relationship as a cause. But in other types, such as acute or even chronic induced, these factors can contribute.

Is hives a hormonal response in the body?

No, urticaria does not happen due to the action of a hormone, but because of the presence of the substance histamine.

This substance is released by mast cells, cells belonging to the connective tissue.

Its release is a natural process, but when it occurs in large quantities it ends up resulting in the symptoms of urticaria.

This means that itching, wheals and swelling are caused by this substance and that there is no interference from a hormone.

Does food interfere with the symptoms of spontaneous chronic urticaria?

Patients with chronic, spontaneous or induced urticaria do not have to worry about maintaining specific care with their diet. This is because it does not interfere with the symptoms or the evolution of the disease.

The only recommendation is to maintain a certain care with the consumption of foods containing the yellow dye Tartrazine, as it can cause some allergic reaction and aggravate the symptoms of the disease.

This reaction to the dye, however, does not happen in all cases and is different from an allergic urticaria.

It is important to know that this dye can cause some reaction. But that does not mean that all patients with chronic urticaria will have the same response after contact.

Does spontaneous chronic urticaria hurt?

The symptoms of ECU cause great discomfort, but pain is not put as a common symptom.

Patients often experience pain due to other symptoms, but this is also related to external factors and not just what the disease causes.

For example, in crises, patients may experience greater swelling and wheals may appear in larger sizes.

In such cases, more delicate people may experience pain when wearing clothes with greater contact with the wheals or that are tighter.

Even other people’s touch can become uncomfortable. However, the pain should not be something that the patient has to live with. If the pain is recurrent, the patient should consult a doctor about what can be done to reduce it.

Which doctor should I look for?

The patient who has some urticaria can be accompanied by specialists such as the dermatologist, immunologist and allergists.

They will be responsible for the diagnosis and guidance for the specific treatment for each case.

People who have any of the symptoms of the disease may, as a first contact, see a general practitioner or pediatrician.

How long does it take for spontaneous remission of the disease to happen?

There is no standard time, so remission is different for each patient. When it should happen is something that has yet to be answered.

However, there is some research that shows important numbers for patients.

A study published by the European Academy of Allergy and Clinical Immunology (EAACI), carried out with 139 UC patients, followed for more than 5 years, showed that the duration of the disease was linked to the severity of the symptoms.

In 70% of the patients, the symptoms persisted for more than 1 year, in 14% of them the duration was longer than 5 years.

This means that remission can take more than 5 years to happen. There are more rare cases in which patients have had symptoms for more than 10 years, but the percentage is 2%.

Even without remission, with the right treatment, patients are able to lead quality lives without symptoms.