What is FROP, classification, cause and Psychosocial factors

Specialists from the gastroenterology department of the Altai Regional Clinical Center for Maternal and Child Health spoke about functional disorders of the digestive organs (hereinafter FDG) in children. In the general public, they are known as colic and regurgitation, but they should be treated with due attention, since the manifestations of FDG can be similar to the symptoms of a number of serious diseases.

What is FROP?

Functional digestive disorders are conditions in which a number of symptoms appear that significantly worsen the child’s quality of life. But the symptoms do not have organic pathology. Modern diagnostic methods are not able to detect pathological changes in functional disorders, but the child is bothered by abdominal pain, bowel disorder, bloating, vomiting, nausea and similar problems.

Functional disorders of the digestive organs are a complex of constant or periodically recurring symptoms that are not explained by organic disorders. Functional disorders do not affect the timely development of the child and can occur as a result of maladaptation of the body.

FROP classification

Functional disorders of the digestive organs in children are usually classified according to age categories.

So, in infants under one year of age these include:

• infant regurgitation;
• infant colic;
• infantile dyschezia (painful defecation, difficulty emptying the bowels;
• functional constipation.

In young children (1–3 years old), FROP includes cyclic vomiting syndrome, functional abdominal pain, and functional constipation.

FROP in children and adolescents (3 to 17 years) includes:

• functional disorders with predominant symptoms of nausea and vomiting;
• recurrent cyclic vomiting syndrome;
• functional nausea and vomiting;
• functional disorders with abdominal pain;
• functional dyspepsia;
• functional abdominal pain;
• dysfunction of the biliary tract (gallbladder and bile ducts);
• functional constipation.

Causes of FROP

Functional disorders of the digestive organs can occur in the form of a combined model and develop due to a number of pathophysiological and psychosocial factors.

Mechanisms of pathophysiology

Disorders of the motor function of the gastrointestinal tract are the most common. This is not only a violation of the motor function due to age-related features of the nerve ganglia and smooth muscles, but also dysfunction of neuroendocrine regulation, which may depend on various risk factors, such as diet, microbial metabolites, CNS signals, etc.

The cause may be individual hypersensitivity to certain products. For example, intolerance to products containing carbohydrates, gluten, dietary fiber, fatty and fried foods, etc.

Visceral sensitivity disorders are less common. This factor is characteristic of functional dyspepsia, irritable bowel syndrome, and infantile intestinal colic. This condition can also be a consequence of chronic inflammation and impaired neuroendocrine regulation.

Disturbances of the intestinal microbiota accompany most functional disorders of the digestive organs regardless of age. When the composition of the microbiota changes, the range of products involved in their metabolism may also change. A number of studies have shown a decrease in the level of short-chain fatty acids and an increase in the quantitative indicator of toxic metabolites, which can have both a local irritant effect and a general toxic effect.

In chronic inflammatory processes, most patients show signs of inflammation of the mucous membrane at the microscopic level. This may be due to increased permeability of the intestinal barrier. This factor may also indicate the presence of a long-term sluggish inflammatory process. Inflammation and motility are directly related to each other and interact at the level of the immune and nervous systems of the intestine.

Psychosocial factors

The symptom complex of functional disorders of the digestive organs may manifest itself as a result of disruption of interaction processes at the level of the central nervous system (for example, during periods of negative psychological impact). Ultimately, a disruption occurs between the interaction of the “brain-gut”, as a result of which the serotonergic system is activated, hyperproduction of serotonin occurs, which causes an increase in pain syndrome.

The formation of the digestive and motor functions of the gastrointestinal tract, as well as the formation of the intestinal biocenosis, the maturation of the central and enteric nervous system, occurs in the first months of a child’s life.

Parents should take into account the variety of clinical manifestations of functional digestive disorders. If certain symptoms occur, it is necessary to seek help from a pediatrician so as not to miss the clinical manifestations of severe gastrointestinal diseases that have similar clinical manifestations to functional digestive disorders.