What Is Atypical Cystic Fibrosis? Everything To Know
Atypical cystic fibrosis is a milder form of cystic fibrosis (CF), a degenerative condition that parents pass to their children. Atypical CF symptoms tend to be milder, and people may not know they have the condition until adulthood.
CF is a condition that affects the lungs, the digestive system, and other organs. It causes a person's body to produce sticky, thick mucus or sweat that can obstruct or damage tubular organs. It is a result of a mutation in the cystic fibrosis transmembrane receptor gene (CFTR) gene.
Atypical CF can cause fluctuating symptoms that are typically less severe than those of typical CF. The organs that atypical CF affects can also vary from person to person.
This article discusses the symptoms and causes of atypical CF. It also looks at treatment options, diagnosis, and more.
A person with atypical CF may experience respiratory symptoms that are milder than those of typical CF. These can include:
CF is a genetic condition. As with typical CF, scientists believe that atypical CF results from mutations in the CFTR gene.
People with atypical CF will usually have one severe CF mutation on one of their chromosomes and one less common, mild CF mutation on the corresponding chromosome.
They may also have an abnormal number of trinucleotide repeats in the CFTR gene on one chromosome and one severe mutation on the other.
Because the symptoms of atypical CF are very similar to those of typical CF but milder, treatments for atypical CF are generally the same as those for typical CF.
Treatments can include:
Close follow-ups with a doctor specializing in CF treatment can help identify any complications early and allow for appropriate treatments to help extend the life expectancy of a person with atypical CF.
Learn more about CF treatments.
Atypical CF can be difficult to diagnose because the symptoms can be mild, varied, and slow to progress.
If a doctor suspects atypical CF, they can order various tests that may help them reach an accurate diagnosis.
Sweat chloride testingSweat chloride testing is now the standard test to diagnose CF in adults. It can also help diagnose atypical CF in cases where a person has elevated chloride levels.
To perform this test, a healthcare professional will apply an odorless, colorless chemical and a small amount of electrical stimulation to a person's leg or arm to detect levels of chloride in their sweat. A hospital lab will then test the sweat to analyze the chloride levels.
Genetic testingGenetic testing can help confirm the diagnosis if the CFTR gene mutation is present.
For this test, a person must provide a sample of their blood, skin cells, or saliva.
Doctors have been diagnosing atypical CF since the 1960s. However, because doctors may identify many of its symptoms as other conditions, atypical CF can be hard to diagnose, and many doctors may initially misdiagnose it as another condition or group of conditions.
For this reason, although there is no specific age at which people are most likely to receive a diagnosis of atypical CF, people usually receive a diagnosis in adulthood or older adulthood.
One 2020 case report describes a person who received a diagnosis of CF at age 57 years despite having numerous symptoms since childhood. Another 2020 case report details a person who experienced numerous CF symptoms and received a diagnosis of atypical CF at age 30 years. In this second case, doctors were able to diagnose CF through sweat chloride testing.
Because CF can be hard to diagnose, people living with it may not receive the treatment they need and may be more likely to die from the condition. If a person thinks they may have symptoms of atypical CF, they should consult a doctor promptly so they can receive an accurate diagnosis as early as possible.
About 1,000 people receive a CF diagnosis each year, and around 10% of all CF diagnoses occur in adulthood.
Here are some more frequently asked questions about atypical CF.
What is the life expectancy for a mild case of cystic fibrosis?Due to the difficulties in diagnosing atypical CF, experts have had trouble finding a specific answer to this question.
While adults who receive a diagnosis of atypical CF generally have longer life expectancies than those with typical CF, experts still do not know the long-term outcome for many people with atypical CF.
Starting treatment as early as possible may help reduce symptoms and improve quality of life.
Can you have mild cystic fibrosis and not know it?It is very possible to have mild CF or atypical CF without realizing it because healthcare professionals may mistakenly attribute the symptoms to a related condition.
For this reason, a person should contact a doctor if they suspect they may have CF or if they have experienced symptoms or conditions such as:
Atypical CF is a milder form of CF. Symptoms can vary from person to person and can lead to misdiagnosis because they are similar to those of other conditions.
A person with atypical CF may not realize they have the condition until later in life. People typically receive the diagnosis in adulthood.
A sweat chloride test or genetic testing can help healthcare professionals diagnose atypical CF. Receiving an accurate diagnosis and starting treatment as early as possible can help a person manage symptoms and experience the best possible outlook for the condition.
Cystic Fibrosis
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What To Know About The Sweat Test For Cystic Fibrosis
The sweat test involves measuring the amount of chloride in sweat. Doctors may use the sweat test to help diagnose cystic fibrosis, as cystic fibrosis causes higher amounts of chloride in sweat.
The sweat test can be useful for diagnosing cystic fibrosis in babies, children, and adults. A doctor may order a sweat test if a person has symptoms of cystic fibrosis or as part of a newborn screening test.
Read on to learn more about the sweat test. This article discusses how it can help diagnose cystic fibrosis, what the test involves, who might need it, and more.
The sweat test is a test that measures the amount of chloride a person has in their sweat.
Each person's body contains two copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The genes produce the CFTR protein.
When a person has cystic fibrosis, the CFTR protein does not work properly. This can cause chloride, which is a component of salt, to become trapped in the cells.
This can result in more chloride in a person's sweat. If the sweat test detects higher chloride levels, this can indicate cystic fibrosis.
Learn more about diagnosing cystic fibrosis.
The sweat test involves placing pads soaked in the chemical pilocarpine on the lower arm or leg. This helps to stimulate sweat production.
A small electrical current will then be passed through the pads for about 5 minutes. This helps the chemical to seep into the skin. It does not cause any pain.
Afterward, the sweat will be collected with a piece of gauze, filter paper, or a small plastic coil. This will typically last for about 30 minutes.
A doctor may order a sweat test if a child or adult has symptoms of cystic fibrosis. They may also recommend the test if a person has a family history of cystic fibrosis.
The sweat test may also be carried out as part of newborn screening tests. Babies in the United States are screened for a variety of conditions after birth, including cystic fibrosis.
If the heel prick test indicates that the baby might have cystic fibrosis, a doctor may order a sweat test to confirm the diagnosis.
Learn about cystic fibrosis and genetics.
A doctor may recommend not applying any creams or lotions to the arms or legs in the 24 hours before the sweat test.
A person will typically not need to do anything else to prepare for a sweat test.
If the sweat test measures a low level of chloride salts, then this typically suggests that the person does not have cystic fibrosis.
If the sweat test measures a high level of chloride, then this may indicate cystic fibrosis. A doctor may then order blood tests to confirm the diagnosis.
In some cases, the results may be inconclusive. If this is the case, a person may need to take another sweat test.
A sweat test is a test that can help with diagnosing cystic fibrosis. It measures the levels of chloride a person has in their sweat.
The test involves placing pilocarpine-soaked pads on the skin and passing a weak electrical current through the pad. Afterward, the sweat will be collected to test the level of chloride.
A person may need this test if they have symptoms or a family history of cystic fibrosis. It may also be necessary if a baby's heel prick test suggests that cystic fibrosis might be possible.
A high level of chloride can indicate cystic fibrosis. Blood tests can then help to confirm the diagnosis.
