the test that detects congenital diseases such as cystic fibrosis

The immunoreactive trypsinogen test (IRT) has been performed by law since 2015 on all newborns in Puerto Rico.

The heel prick test allows doctors to identify the condition before children have symptoms. Photomontage: Journal of Medicine and Public Health.

The heel prick test, technically known as the immunoreactive trypsinogen test (IRT), is performed to detect early congenital diseases such as cystic fibrosisprimary congenital hypothyroidism, phenylketonuria and congenital adrenal hyperplasia.

Cystic fibrosis

The cystic fibrosis It is a genetic disorder that affects different areas of the body, including the lungs, pancreas, liver and intestines, causing a buildup of thick, sticky mucus in those areas.

It is estimated that there is a 25% chance that the child will be born with disease, and 50% that he is a carrier of the gene, but does not show it. In this regard, Dr. Wilfredo de Jesus Rojas, a pediatric pulmonologist, and Jesus Melendez Montanez, a medical student in Puerto Rico, spoke to the Journal of Medicine and Public Health about the importance of basic screening tests for cystic fibrosisthe role of genes in the associated manifestations and the main treatments available to patients.

The CFTR gene, the mutation responsible for the disease

“CF can affect the skin, the way we eat and breathe. It affects all the tubes that we have in the body because they are filled with secretions because of a gene, the CFTR gene, that is affected and the patient inherits this mutation,” explained Dr. Wilfredo de Jesus.

In this regard, Jesus Melendez also pointed out that studies have been shown in Puerto Rico where patients who are carriers of this gene may have CF and develop pancreatitis, a secondary complication.

“In the studies we’ve seen in Puerto Rico, if you carry one of the many variants of the CFTR gene of cystic fibrosischances are you have disease and develop pancreatitis without knowing it. That is why it is important to be able to diagnose this disease in advance. disease“, he added.

Heel prick test and diagnosis of cystic fibrosis

In this sense, the heel prick test becomes more important, because through the blood test of newborn look for increased levels of immunoreactive trypsinogen (IRT), a protein produced by the pancreas that is associated with cystic fibrosis.

According to the medical literature, children with CF who are diagnosed with CF disease early and starting treatment can have better nutrition, growth and lung function. This screening test allows doctors to identify children with the disease before they have symptoms.

“During the investigative process, we learned that prior to 2015 in Puerto Rico, at least unlike the United States, the heel prick test was not required by law to cystic fibrosistherefore, there may be a large portion of Puerto Rico’s population that does cystic fibrosis or is a carrier and doesn’t know it,” said the medical student.

Although there are no population statistics in Puerto Rico with cystic fibrosisit is estimated that 1 in 17,000 children are born annually with disease.

“One of the things we know is that this condition can be presented as homozygous, which is when both parents have the mutation and it passes to the child with two mutations, which can be in the same component of the gene or in different areas. This patient is going to have a slightly more severe clinic than others who may be carriers of the disease,” emphasized the pediatric pulmonologist.

warning signs

The main signs that parents can identify in suspicious children cystic fibrosis is poor growth, increased secretion in the lungs, recurrent cough with sputum, weight loss, diarrhea or even constipation and abdominal pain. For detection, the sweat test is used to check the amount of chlorine in the skin, in addition to other genetic tests that check whether the patient has mutations.

The specialist also warned that if appropriate treatments are not carried out, patients can experience difficulty breathing, get persistent infections and increase the risk of colonizing bacteria that damage the lungs.

Modern treatments for cystic fibrosis

“When we start treatment early, the story may be different. A patient who remains undiagnosed for a long time has a shorter life expectancy. In the last 10 years, life expectancy has varied between 30 and 40 years, and we understand that with new treatments, life expectancy can be increased,” added Dr. Vilfredo de Jesus.

Likewise, professionals emphasized that recent research, treatments and diagnostic tools have made early detection of the condition possible, and that is the goal they have for the Puerto Rican population.

“We know that a patient born with CF needs long-term treatment, which includes therapies that are used in the morning and in the evening. Our pediatric patients wear a vest that vibrates to help mobilize bodily secretions,” said Dr. Wilfredo de Jesus.

“Science is advancing with new treatments and there are drugs today that try to correct this genetic problem and help the patient not need such long-term drugs. They improve lung function and maintain weight, although they are expensive treatments; it’s estimated that a CF patient can spend $10,000 to $30,000 a year on treatment,” admits the specialist.

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