Genetic diseases

Cystic fibrosis

Cystic fibrosis

cystic fibrosis photo Cystic fibrosis (from the Latin. «Muscus» - refers to the mucus or slimy, «viscidus» - sticky) - a heavy congenital disease characterized by lesions of exocrine glands and causes abnormal respiratory anddigestive system. Most cystic fibrosis develops in childhood.

The child cystic fibrosis manifest when even one of the parents is a carrier of the gene CFTR mutated.Every year around the world more than 45,000 children born with hereditary pathology of cystic fibrosis.This disease has a social value in connection with a progressive nature of the current and possible subsequent deaths and disability of many patients.

Cystic fibrosis causes

mutation of genes - is the absolute basis of the disease.If heterozygous - both parents, the possibility of the birth of a child with cystic fibrosis patient in a family is equal to 25%.A carrier frequency of genes in common - 2-5%.

At the end of the last century, scientists have deciphered the genetic-structure of the gene responsible fo

r a protein compound.He called CFTR, cystic fibrosis transmembrane means that the controller.This protein regulates the movement of electrolytes through the cell membranes that line the ducts of exocrine glands leading out.But due to a mutation of this gene is a violation of all the structures and functions of protein, so secretory liquid, which release cancer becomes thick, viscous contents.As a result, it affects such important organs like the pancreas, gastrointestinal tract and lungs.

The process of mutation is characterized by loss of the triplet that encodes amino phenylamine.Molecule of the mutated gene have impairments in the position of losing its 508 amino acid residue.Thus, there was such a name - delta 508. At this point already known and studied over 120 different types of mutations are involved in the development of pathology.Such a great number of them can give an explanation in a variety of clinical pictures of cystic fibrosis.Pretty heavy manifestation of the disease in the early stages observed in patients homozygous F 508. A patients with no F 508 different clinical polymorphism, that is, at the same time they are diagnosed with severe forms of disease, early symptoms and a poor outcome with a relatively good performance of the disease at an older age andduring adolescence.

Cystic fibrosis symptoms

There are a few basic forms of cystic fibrosis - lung and intestinal, respiratory and intestinal.Much less can be found in the medical practice, meconium ileus, edematous-anemic, and other forms.

most severe form of cystic fibrosis is considered to be manifestations of a mixed form of the disease.She meets 75% of cases.The history of these patients noted repeatedly arduous bronchitis and pneumonia, and sometimes even with a long history.Watched the clinical picture of a persistent cough with viscous sputum allocated, frequent violations of the gastrointestinal tract.But clearly the most serious changes are taking place on the part of the respiratory organs.The increased viscosity of the secretions from the allocation of the mucous glands of the bronchi mukostaz it creates and leads to infection, which makes it possible to manifest and progress to chronic bronchitis, which resulted in him there is a characteristic painful cough with hard discharged viscous sputum, besides pus.

Bronchopulmonary changes are an integral part of all violations of bronchial patency system.Changes that occur as a result of self-cleaning, tends to cause clogging of the bronchioles and bronchi of small parts.Developing emphysema as a result of stretching airspace as a result of a complete blockage of the bronchi, there are all the signs of atelectasis.They may be small, and alternate with areas of emphysema.

In severe clinical picture sometimes simultaneously with such changes appear microabscesses that often affect bronchial submucosal glands.Then the lightning starts to progress the lung parenchyma, that is monitored by an acute form of pneumonia, which differs in patients with severe, protracted course of cystic fibrosis clinic, prone to abscess formation.

Periodically, the first manifestation of the pulmonary form of cystic fibrosis can sometimes occur on the second or third year of life, as well as at a later date.The nature of these manifestations is becoming a prolonged and severe form of pneumonia.

Older children more often presented with a clinical picture of protracted bronchitis with conspicuous obstruction.The changes caused by inflammation, manifested by diffuse bronchitis, which often recurs in different protracted pneumonia, and then quickly turn into chronic inflammation of the lungs.Then gradually develop bronchiectasis, and pulmonary fibrosis.Amazed interstitial tissue and it gets the results of the pulmonary fibrosis.Therefore, in both lungs tapped moist, but more finely wheezing.

extremely adverse effect on the course of the development of cystic fibrosis has extensive fibrosis and bronchiectasis followed by the formation of purulent process.All kinds of obstructive changes observed in cystic fibrosis, in the course of progression, lead to increased symptoms of emphysema, a very pronounced disruption of visual and respiratory pathologies of the pulmonary circulation.

parallel with the underlying disease, the deformation of the chest, the terminal phalanges take the form of drum sticks, as well as the type of pulmonary heart develops heart failure.

pneumoempyema, pneumothorax and pulmonary hemorrhage are relatively rare complications of cystic fibrosis.But if the disease is characterized by a long duration, then celebrate the defeat of the nasopharynx, which include polyps, adenoids and chronic tonsillitis.Almost all children are diagnosed with sinusitis, clinical manifestations which marked nasal voice, headaches and allocation of secretion from the nasal passages.

In clinical disorders of the bowel, and pancreas develops all the symptoms of cystic fibrosis patients of the main forms of the disease.But the changes that can reduce the activity of pancreatic enzymes work, particularly in children transferred to artificial feeding, can manifest sufficient breakdown of proteins and fats, as well as their absorption.Therefore enteric putrefaction develop, which lead to the accumulation of gases and bloating constant.As a result, even if the first examination of the patient, cystic fibrosis can be assumed, taking into account the characteristic abundant chair with putrid malodorous.Almost 20% of patients have rectal prolapse.

Among some abdominal symptoms allocate such as frequent abdominal pain of various etiologies.They are the type of cramping flatulence, pain in the muscles from prolonged paroxysmal cough in the right upper quadrant, in the liver.

Localization epigastric pain may occur because not enough neutralize gastric acid in the duodenum.This occurs as a result of violations of pancreatic secretion.Therefore, a large number of patients who died, often with negative results biochemistry autopsy states biliary cirrhosis type.In patients with cystic fibrosis there is increased appetite, but persistent indigestion continuously lead to malnutrition.Sometimes, but very rarely develop gipoproteinemicheskie swelling.Malnutrition contributes to the development of both developing hypochloremia, anorexia, and metabolic alkalosis.

Cystic fibrosis in children

Since cystic fibrosis - one of the leading common today hereditary diseases, the frequency of its occurrence among children of all ages is very great.In addition to the likelihood of developing it will not affect the child's affiliation to a certain floor.The disease does not choose - boy or a girl.The main thing to learn that cystic fibrosis in children develops only by genetic defects.Therefore, no bad habits, social status or environmental problems can not be a probability of children born with cystic fibrosis pathology.

children diagnosed with the disease only when they have two mutant genes, which they got in the inheritance from their parents.Therefore, in families where the wife, with both carriers of the cystic fibrosis gene, the children will be born with the disease.But those who have inherited from their parents, only one form of this gene would be considered carriers of cystic fibrosis.These children are born perfectly healthy.

Children secrete a wide variety of clinical manifestations of cystic fibrosis.With some changes can be detected on the part of the respiratory system mostly diseases of the bronchi and lungs, while others - a heavy defeat of the pancreas.The clinical course of the disease form, each child can take place in different ways.

important to remember that cystic fibrosis - a genetic disorder which affects the mental ability is not the child.

In the first months of life for many children, malnutrition stands while maintaining appetite and only after some time in the stool, and polifekalie formed by fat, which is alarming parents infants, so they give it special attention.

leather baby is a good sign for the diagnosis, since it has a "salty" taste.Therefore, with such a complaint, the parents for the first time, seek the advice of a pediatrician.Perhaps these children will manifest harshly hypokalemia and metabolic alkalosis due expressed electrolyte abnormalities.

In cystic fibrosis, the part of the respiratory system, cough is the first symptom of the disease.In the beginning, it will manifest itself in the form of "cough", then gradually increase and take on the character of cough like whooping cough.In children, cyanosis and shortness of breath may accompany this paroxysmal cough, breathing stops but usually does not happen.Released sputum by coughing, early in the disease, light-colored and viscous, but she later becomes mucopurulent and acquires a strong viscosity.If there was a greenish sputum, then it is a signal appears in the body of the child and her Pseudomonas aeruginosa infection sputum.In many cases, often fixed SARS, which are recurrent and have a prolonged duration and a cough that lasts for a long time yet.

In the initial stage of cystic fibrosis disease picture auscultation infants sometimes normal.A careful examination of the child makes it possible to detect an increased anteroposterior dimension of the chest, shortness of breath small with little physical activity and reduced pulmonary excursion.

the part of the gastrointestinal tract in infants reveal loose stools a greenish color, which later becomes a greasy appearance.A child with cystic fibrosis has a body weight does not correspond to healthy peers, that is behind in physical development and later growth.Children with cystic fibrosis, by visual inspection have reduced muscle mass, stomach bulging out, and rectal prolapse is often a symptom of this pathology.

addition to the basic forms of cystic fibrosis, for example, 15% of patients develop neonatal meconium ileus.Symptoms of this type of pathology can be vomiting bile, inability to discharge of meconium, and an enlarged abdomen.Grey meconium is delayed in the small intestine, in the ileocecal valve.The most dangerous manifestation of this form of cystic fibrosis is a complication in the form of his meconium peritonitis.

combination of all these pathological processes from respiratory system, digestive system and sweat glands, usually leads to the degeneration of the child.Hypoproteinemia and anasarca in infants occur in conjunction gemoleticheskoy anemia.Often, such children have a lack of fat-soluble vitamins.For example, the cause of bleeding is a vitamin K deficiency as a result gipoprotrombinemii.

children suffering from cystic fibrosis, characterized by sudden loss of salts in perspiration, as a result of the heat, frequent inflamed sinuses, which are complicated by polyposis and the defeat of the parotid glands.80% of affected children have an increased sensitivity to different types of allergens such as food, household and medical.

One of the complications of cystic fibrosis in children is celiac disease, but there is a common complication of cholelithiasis.

Cystic Fibrosis diagnosis

diagnosis of cystic fibrosis is the foundation of chronic bronchopulmonary process, intestinal syndrome, a positive sweat test, cystic fibrosis and siblings.Therefore, for the diagnosis of this pathology is enough to have any two of these enumerated grounds.Already developed specific criteria for the diagnosis of cystic fibrosis, which include two diagnostic species.

The first is based on the characteristic clinical symptoms.It may be as the presence of the family cases of cystic fibrosis and neonatal screening for immunoreactive trypsin positive character.

second - a high content of chloride in the sweat (60 mmol / L) identified two mutations, a positive result during the measurement nasal potential difference.The diagnosis is reliable, even if there is one of each type of test diagnostics.

to diagnose cystic fibrosis have resorted to a number of methods that are quite informative, but also time consuming.To do this, you must determine the concentration of sodium chloride in the sweat, feces scatology conduct research, make a diagnosis DNA measure nasal potential difference, to determine the activity of pancreatic elastase in the feces.

Currently, there is a real opportunity to carry out more prenatal fetal the presence of cystic fibrosis, due to the existing DNA diagnostics.And be sure to do a survey of prospective parents before planning pregnancy, that is, to determine the presence or absence in the body of the gene for cystic fibrosis.

Today, most families who have a sick child with cystic fibrosis, but the past this kind of diagnosis, as DNA, have children in the future is already quite healthy.

Analysis for cystic fibrosis

There are a number of samples, diagnostics and tests that are used in the diagnosis of cystic fibrosis.In the first months of life in infants can spend neonatal diagnosis.This method consists in determining the amount of the content of IRT in the blood of the child.TIB - a pancreatic enzyme.If your child is ill with cystic fibrosis, the analysis on the IRT will be a rate increase.Such an analysis is made, if there is suspicion of cystic fibrosis.

most effective diagnostic test for cystic fibrosis is a sweat test.Standard procedure is that the sample is taken sweat patch of skin, which was previously conducted using pilocarpine iontophoresis.The concentration of NaCL in the secretions of the sweat glands should not exceed 40 mg / dL.If the result of the test specimen above 60 mmol / L, it can be considered positive.The important point is to conduct a re-analysis.It is made in the case, if the answer came positive, doubtful or negative, but the clinical picture suggests the likelihood of having cystic fibrosis.

In order to definitively diagnose it is necessary to conduct several of these samples, two or three and get positive confirmation.

But sometimes the answers come false.This can be due to inaccurate material collection and transportation;sampling a newborn or patient taking cloxacillin.

Among the methods of investigation and allocate more scatological.Exploring scatology feces patients can detect steatorrhea.This is due to the fact that the duodenum has low or no activity in her pancreatic enzymes.

chest X-ray can identify the seal of the bronchi, and also note an increase airiness of lung tissue.Chest X-ray shows signs of wears off segments of the lung, especially the upper lobe.

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