What causes biliary dyskinesia?

The main cause of biliary dyskinesia in children is a disruption in the interaction of the nervous and paracrine systems that ensure the sequence of contractions and relaxations of the gallbladder and the sphincter system, leading to discoordination of their activities and disruption of the passage of bile into the intestine. Biliary dyskinesia is a functional disease, since there are no organic changes or signs of inflammation in the biliary system. The main causes of biliary dyskinesia are:

• anatomical features that impair emptying (kinks and deformations of the gallbladder, anomalies in the structure of the bile ducts);
• functional disorders of the muscular system, especially the sphincter;
• dyscholia (cytogenic, hepatogenic) - change in the composition of bile.

Bile is a complex colloidal system. Its main components (60% of organic matter) are bile acids: 35% is chenodeoxycholic acid, 35% is cholic, 25% is deoxycholic. Bile also contains phospholipids (25% of organic substances in bile), proteins (5%), bilirubin (5%) and cholesterol. Entering the gastrointestinal tract, bile performs numerous digestive functions: emulsification of fats, activation of pancreatic enzymes, ensuring optimal pH in the duodenum, ensuring lipid absorption in the small intestine, stimulation of intestinal motility, increased absorption of fat-soluble vitamins, suppression of putrefactive microflora in the colon. Bile secretion is an important link in the elimination of many xenobiotics, in the regulation of cholesterol metabolism and other metabolic processes in the human body. Bile secretion occurs both under the influence of food and in the interdigestive period. During digestion, bile secretion and biliary motility increase, the gallbladder contracts and the sphincters relax and contract in a coordinated manner.

Some exogenous and endogenous factors cause biliary dyskinesia. The occurrence of dyskinesia is associated with previous infectious diseases - epidemic hepatitis, dysentery, salmonellosis. Particular attention is paid to intestinal giardiasis, various dietary disorders. A certain role in the occurrence and development of biliary dyskinesia belongs to foci of chronic infection (chronic tonsillitis, sinusitis, etc.). The dependence of biliary tract pathology on various neurotic conditions is traced. The causes of dyskinesia can be allergic reactions, intestinal biocenosis disorders, insufficient physical activity.

A close relationship between the biliary system, stomach, duodenum and pancreas is provided by neurohumoral factors - primarily intestinal peptide hormones. Cholecystokinin-pancreozymin contracts the gallbladder, facilitating the flow of bile into the duodenum. Gastrin, secretin, glucagon have a slightly lesser stimulating effect. Enkephalins, angiotensins, neurotensin, vasoactive neurohumoral peptide inhibit gallbladder motility. Impaired production of peptide hormones and disturbances in their relationship lead to changes in the contractile function of both the gallbladder and other parts of the biliary system and pancreatic ducts. This causes an increase in pressure in the gallbladder and hypertonicity of the sphincter apparatus, contributing to the appearance of pain syndrome of various natures.

The following factors influence the secretion of bile from the gallbladder:

• pressure gradient in the duodenum;
• neurohumoral factors (cholecystokinin, gastrin, secretin);
• central nervous system (conditioned reflexes to the sight of food);
• autonomic nervous system (sympathetic, parasympathetic);
• endocrine glands (pancreas, thyroid gland, pituitary gland).

Classification of biliary dyskinesia in children

Dyskinesia of the biliary tract in children is divided into primary and secondary.

1. Primary diseases include diseases that are based on disturbances in neurohumoral regulatory mechanisms.
2. Secondary dyskinesias are caused by organic lesions of the liver, stomach, and duodenum, arising as viscero-visceral reflexes. In addition, the motility of the biliary tract depends on the functional state of the duodenum.

In the practical work of a pediatrician, combined pathological conditions characterized by biliary dyskinesia and changes in adjacent digestive organs are most often encountered. It is necessary to take into account that biliary dyskinesia may be only one of the special cases of impaired motility of the entire gastrointestinal tract.

The main causes of biliary dyskinesia:

• autonomic dysfunction (the most common cause of functional cholepathies);
• pathology of the gallbladder, dyskinesia against the background of organic disorders;
• pathology of other digestive organs (due to disturbances in nervous and/or humoral regulation).

Disorders of the biliary tract motility are divided as follows:

• dysfunction (dyskinesia) of the gallbladder - hypo- and hyperkinetic (hypo- and hypermotor);
• dysfunction (dystonia) of the sphincter of Oddi (hypo- and hypertonic).

The assessment of motility is based on measuring the diameter (normally reduced by 1/3) and volume (reduced by 33-66%) of the organ.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ]