What is cystic fibrosis?
It is a genetic disease that affects both young children and adults. It mainly affects the lungs and the digestive system. When a child inherits two copies of the genes responsible for cystic fibrosis, the child develops the disease.
The complications associated with the disease are:
- Difficulty digesting fat and protein
- Vitamin deficiency
- Inability to absorb nutrients
- Lung damage due to infection and inflammation
- Cystic fibrosis-related diabetes (CFRD)
- Sinus infection
Symptoms of cystic fibrosis include:
- Severe coughing
- Coughing up thick mucus
- Chest infection
- Bowel obstruction
- Salty sweat
- Shortness of breath and other respiratory problems
The doctor may first perform a sweat test to measure the salt level in the sweat. Other diagnostic methods are genetic testing and newborn screening.
Cystic fibrosis can cause severe damage to the lungs, digestive system, and other organs. It also affects the production of mucus, digestive juices, and sweat. Normally, these secretions are thin and slippery, but in a person with cystic fibrosis, these secretions are sticky and thick.
History of Cystic Fibrosis
Cystic fibrosis is also known as mucoviscidosis, which is a rare genetic disorder. In this condition, there is an excessive production of mucus, shortness of breath, and severe coughing. A child born with this disease may suffer from a meconium ileus attack. Moreover, congenital bilateral absence of the vas deferens (CBAVD) is strongly associated with cystic fibrosis.
One in every 4,000 Caucasian children may get the disease whereas the risk is much lower in African and Asian American children. However, people of Mediterranean or Finnish descent have the highest incidences of cystic fibrosis carriers. The first written record was in Swiss and German literature in the 18th century.
In the 19th century, some deaths that occurred were linked to meconium peritonitis. At that time, the disease was not known, but today, we know that cystic fibrosis is associated with meconium ileus in babies.
In the 17th century, a European song has indicated the quotation, "The child will soon die whose forehead tastes salty when kissed." It refers to the condition of children who lose too much salt through their sweat.
A truly documented history of cystic fibrosis did not exist until the 1930s. Many cases of cystic fibrosis were misdiagnosed. They were thought to be chronic bronchitis, pneumonia, or whooping cough. However, since the 1700s, there has been some awareness of what cystic fibrosis is even though there was a lack of history. The disease was considered to be a disease of its own nature.
An earlier paper about the disease was written by Dr. Franconi, a Swiss pediatrician, and his colleagues. He called it as celiac disease, which is a pancreatic disease.
In the 1930s, Dr. Dorothy Hansine Andersen was the first to recognize cystic fibrosis as a disease. Andersen performed an autopsy of a child who had celiac disease when she noticed a pancreatic lesion. Following an extensive research of related medical literature and autopsy records, she found a disease pattern that was unrecognized and unclear. She called the disease as cystic fibrosis since there were cyst formations and scarring of the pancreas. The first comprehensive medical report on cystic fibrosis was written by Andersen in 1938. After many years of working, she came up with many diagnostic tools, one of which is still being used today. Moreover, she theorized that the cause of cystic fibrosis is vitamin A deficiency.
This decade was marked in history for bringing about changes in the theories related to cystic fibrosis. Dr. Sidney Farber and Dr. Harry Shwachman connected excessive mucus production to cystic fibrosis. A number of researchers challenged the theory that the underlying cause of cystic fibrosis is vitamin A deficiency. It was also challenged by Dr. Dorothy Andersen, who proposed the theory herself. To treat the condition, doctors prescribed the antibiotic called penicillin.
In 1948, Dr. Paul di Sant'Agnese found out that numerous children admitted to the hospital had cystic fibrosis. He discovered it during a heat wave in 1948. Most of the cases were dehydration, which led the doctor to discover that the children’s sweat had more concentration of salt. This observation eventually led to the development of the sweat test, which was considered as a method to diagnose the disease.
In the 1950s, the diagnostic testing for cystic fibrosis began through the sweat test, which is still being used as a standard test nowadays. The discoveries made by Dr. Paul di Sant’Agnese resulted in the development of the test. He helped families and patients suffering from the disease and was involved in the Cystic Fibrosis Foundation in 1955. In 1965, Dr. di Sant'Agnese founded the International Cystic Fibrosis Association.
Aside from the sweat test, physicians also looked for the following symptoms in their patients:
- Chronic cough with sputum production
- Continuous colonization of pathogens such as Staphylococcus aureus, Pseudomonas aeruginosa, Burkholderia cepacia, and Haemophilus influenzae
- Radiographic abnormalities of the chest
- Signs of airway obstruction
- Nasal polyps
- Abnormalities of the gastrointestinal tract
- Clubbed fingers and toes
- Liver disease
- Pancreatitis or its recurrence
- Malnutrition syndrome
- Salt-loss syndrome
- Urogenital abnormalities in males
In the 1960s, an organization was formed, which consisted of people who specialized in cystic fibrosis research. The initiative was taken by parents of children who were affected by the disease and also few patients who survived the disease until adulthood.
The Cystic Fibrosis Foundation Patient Registry (CFFPR) was established in the United States in the year 1966 to help monitor the course of the disease, the effects of treatments, and the health status of patients with CF.
To properly diagnose the disease, preliminary work began on neonatal screening. Moreover, many clinics specializing in cystic fibrosis emerged. There was also an advocacy to treat the disease with a high-fat diet.
During the 1980s, more advancements in the treatment of the disease occurred. The cystic fibrosis transmembrane conductance regulator (CFTR) was discovered in 1989, which greatly helped in the diagnosis of the disease. Moreover, the mutation of this gene made the diagnosis likely possible and correct. Around 70 percent of cystic fibrosis cases were due to the mutation in the gene known as F508del. The CFTR was identified by Collins, Tsui, and Riordan in 1989.
Gene replacement therapy was used. The first mucolytic drug called Pulmozyme for cystic fibrosis was designed and its use was approved by the FDA. This drug became a part of cystic fibrosis treatment.
Various agencies were formed for further research. Fifty years ago, the life expectancy of a person suffering from cystic fibrosis was five years, which have been extended to 37 years in 2005. Experts are hoping that the life expectancy of people with CF will continue to increase in the future.
Numerous factors have helped in increasing the survival of the patients. Factors include effective daily clearance regimens, advances in pulmonary therapy, nutritional therapy, high-fat diet, and antibiotics.
Newborn screening, which includes screening for cystic fibrosis is done in all of 50 states and the District of Columbia. The screening is done in the form of a blood test. Newborn blood is checked for the level of a chemical in the pancreas called immunoreactive trypsinogen (IRT). The first screening test for cystic fibrosis in newborns was done in Colorado, USA in 1982.
The universal newborn screening program was only done in Colorado, Wisconsin, and Wyoming in 1987, but today, all 50 states have it. With the help of newborn screening, it is possible to detect cystic fibrosis at an early age. The early detection and treatment progress has changed the outlook of the disease.
The Senate Cystic Fibrosis Caucus was launched on April 19, 2016. Its aim is to increase awareness about the disease, research support, and advance policies. Now, people with cystic fibrosis have a better life expectancy than the ones who had the disease in the past. Their average life span has improved due to the CF treatment advancement.