Celiac disease

What is celiac disease?

Celiac disease, also called celiac sprue or gluten enteropathy, is a "disease that affects the intestine as the main organ, but which has many important consequences even at a distance, and which depends on an" alteration of the immune response by the T lymphocytes of people genetically predisposed against gluten, which is a substance normally ingested with the diet.

This disease has been known since the first century after Christ, but its relationship with gluten was only discovered in 1940. Celiac disease is prevalent especially in Europe and among populations of northern European origin; among these populations the prevalence of the disease is around 1%.

According to the annual report of the Ministry of Health to parliament on celiac disease, relative to 2012, the prevalence of this disease in the adult population appears to be around 1% in Europe, with a range of variability ranging from 0.3% in Germany. to 2.4% of Finland. Italy is around 0.7%. In 2012 in Italy 148,662 subjects tested positive for the diagnosis of celiac disease, 12,862 more than the previous year. Within the population, the average male: female proportion is 1: 2; this means that for each celiac male there are two females affected by celiac disease.

Causes

Gluten is a component of wheat, barley and rye (not rice, oats or corn); it contains the protein which is responsible for the inappropriate immune response, and which is called gliadin. There are people who, for genetic reasons, are carriers of some variants of what is called Major Histocompatibility Complex type II (MHC II); these are proteins that cooperate with the immune cells and that would provoke the adverse reaction of the immune system itself towards gliadin. Once ingested with the diet, it should be completely broken down by digestive enzymes to obtain individual amino acids. However, it was discovered that there is a component made of 33 amino acids that resists this degradation and that can pass through intestinal cells intact, thus coming into contact with some particular types of cells of the immune system, which have the molecules of MHC II on the These cells internalize within themselves the 33 amino acid component of gliadin, digest it and break it down into smaller particles, which are then returned to their surface and expressed through a binding to MHC class II molecules. results has a strong ability to activate T lymphocytes, which thus initiate an immune response that causes local damage, represented by an "inflammation that takes place in the intestinal wall, and the" activation of B lymphocytes, which produce antibodies against gliadin (anti- gliadin) and other antibodies (called anti-endomysium and anti-transglutaminase), which all belong to the class of immunog lobuline A. An "other relevant consequence that can occur is the induction of a defect in the production of lactase (an enzyme responsible for the digestion of lactose), which also involves an" intolerance to milk and dairy products, if it was not already present.

Celiac Symptoms

For further information: Celiac Symptoms

Celiac disease occurs quite often in childhood, but in reality it can occur at any age, so much so that cases diagnosed after the age of 60 are increasing. The severity of symptoms depends on the extent of the disease along the intestine, as the less extensive forms, which usually involve only the first portion of the small intestine, can cause nuanced problems that are not immediately attributable to the malabsorption syndrome of celiac disease. classical, one subclinical, and a form silent.
In the classic form there are diarrhea, steatorrhea (stools rich in fat and therefore smelly), weight loss and all those problems that are characteristic of global malabsorption, especially as regards vitamins, iron and folate. Sometimes, even in the absence of diarrhea, it is quite common to observe only an "iron deficiency anemia (more rarely also from a lack of folic acid and / or vitamin B12) or aphthous stomatitis (painful ulcers inside the oral cavity) that recurrence.
The subclinical form of celiac disease is characterized by minor, transient, and apparently extraintestinal symptoms, which only the experienced physician refers to this condition.
The silent form is characterized by the absence of symptoms and signs referable to malabsorption.
Both in full and partial forms it is possible that, albeit rarely, phenomena such as an increase in transaminases, an increase in the number of platelets, neurological disorders (alterations in balance, epilepsy), infertility, recurrent abortions, skin alterations such as patches are observed and alopecia It is therefore advisable, in the presence of clinical problems of this type that are not easily explained, to investigate whether celiac disease is in progress.
There is also an "association of celiac disease with other pathologies, such as for example with herpetiform dermatitis, which is a skin lesion characterized by very itchy papules and vesicles localized preferentially to the elbows and knees, trunk and neck, but also with type I diabetes, autoimmune thyroiditis, Sjögren's syndrome, rheumatoid arthritis, IgA nephropathy, Down syndrome, primary biliary cirrhosis, sclerosing cholangitis, and epilepsy. these cases, a propensity to autoimmune diseases, in which the subject's immune system rebels against the cells of the same subject, determines both celiac disease and the associated condition.
This pathology can lead to important complications, such as intestinal lymphomas, tumors of the oral cavity, of the esophagus and of the small intestine or even to important non-cancerous alterations of the small intestine, such as some permanent anatomical alterations of the structure of the small intestine, making malabsorption not correctable by eliminating gluten from the diet.

Diagnosis

For further information: Tests for the diagnosis of Celiac disease

The most accurate diagnosis, in a patient with typical symptoms of celiac disease, is done with a test called a "jejunal mucosa biopsy," which reveals the characteristic lesions. It consists in surgically removing a piece of mucosa of the small intestine (jejunum) and observing it under the microscope (histological and cytological examination). Two biopsies must be performed: one prior to the gluten-free diet, which demonstrates the typical lesions, and one after a year of a gluten-free diet, which must show their significant improvement. The lesions are reversible: in fact, the mucosa returns to a normal appearance after a few months of a gluten-free diet. The biopsy can be performed endoscopically, inserting a thin flexible tube in the patient's mouth and passing it through the esophagus and stomach to the duodenum and jejunum; it allows to perform a targeted sampling in the point where the intestinal wall appears altered. However, there are much simpler methods, through blood sampling , which are performed before the biopsy, and which for this reason are much more widely used, also for studies of scre ening. They consist in the serum search for antibodies characteristic of the disease (anti-gliadin, anti-endomysium and anti-transglutaminase). Positive antibody is not diagnostic, but it is useful in selecting those patients for intestinal biopsy.

Treatment

For further information: Medicines for the treatment of Celiac disease

The fundamental therapy is the elimination from the diet of all foods containing derivatives of wheat, barley and rye, replacing them with rice, corn, potatoes, soy or tapioca. At least initially, it is better to avoid oats. Even beer must be eliminated, while it is possible to freely consume wine and spirits, including whiskey. Unfortunately, small amounts of gluten can also be found in food additives, emulsifiers or stabilizers, or in drugs (capsules and tablets containing starch), it is therefore advisable to check that any food or medicine does not contain gluten. In the presence of celiac disease, it is advisable, at least initially, to abstain also from the consumption of milk or dairy products, since a deficit may also occur intestinal production of lactase.