Irritable Stomach (Functional Dyspepsia): Causes

Pathogenesis (development of disease)

The cause of functional dyspepsia is heterogeneous and multifactorial. The exact pathomechanism of irritable stomach syndrome is not yet clear. However, psychological problems probably play an important role. In addition, hypersensitivity of the afferent innervation of the stomach is probably present (dysfunction of the autonomic nervous system). The dyspeptic complaints are explained by:

  • Increased intragastric pressure, increased wall tension, possibly also disproportionate volume distribution in the stomach (gastric accommodation disorder).
  • Mechanical stimulation (eg, gastric distension).
  • Chemical stimulation (e.g., duodenal lipids).
  • Infectious-inflammatory influences (e.g., postinfectious functional dyspepsia).

Etiology (causes)

Biographical causes

  • Genetic burden-association with polymorphisms of the G protein-β3 subunit, the COX 1 and COMT genes, and the CCK1 and TRL2 receptors.

Behavioral causes

  • Nutrition
    • Dietary habits
      • High-fat meals (inhibition of gastric emptying).
      • Hot spices
  • Stimulant consumption
    • Alcohol
    • Tobacco (smoking)
  • Psycho-social situation
    • Psychological stress
    • Anxiety

Causes related to disease

Respiratory system (J00-J99)

  • Chronic lung disease

Endocrine, nutritional and metabolic diseases (E00-E90).

  • Diabetes mellitus

Cardiovascular system (I00-I99)

  • Coronary artery disease (CAD)
  • Myocardial infarction

Infectious and parasitic diseases (A00-B99).

  • H. pylori infection
  • Parasites (e.g., Giardia lamblia, Strongyloides, Anisakis) [possible pathogenetic mechanisms: postinfectious, mast cell dysfunction, cytokines].

Liver, gallbladder, and bile ducts – Pancreas (pancreas) (K70-K77; K80-K87).

  • Cholelithiasis
  • Pancreatic Cancer
  • Pancreatitis, chronic

Mouth, esophagus (food pipe), stomach and intestines (K00-K67; K90-K93).

  • Chronic mesenteric ischemia
  • Diffuse esophageal spasm – neuromuscular dysfunction of esophageal muscles with intermittent retrosternal pain
  • Eosinophilic gastroenteritis (EGS; synonym: diffuse eosinophilic infiltration of the gastrointestinal tract).
  • Gastritis, acute and chronic
  • Gastroduodenal ulcer disease
  • Gastroenteritis (gastrointestinal flu)
  • Gastroesophageal reflux disease (synonyms: GERD, gastroesophageal reflux disease; gastroesophageal reflux disease (GERD); gastroesophageal reflux; reflux esophagitis; reflux disease; reflux esophagitis; peptic esophagitis).
  • Gastroparesis
  • Hypercontractile esophagus (nutcracker esophagus) – motility disorder of the esophagus characterized by high pressure amplitudes in the lower esophagus.
  • Crohn’s disease – chronic inflammatory bowel disease; it usually progresses in relapses and can affect the entire digestive tract; characteristic is the segmental affection of the intestinal mucosa, that is, several intestinal segments may be affected, which are separated from each other by healthy sections
  • Motility disorders of the esophagus (eg, achalasia).
  • Food intolerances, which can be very individual, such as dairy products (lactose intolerance), coffee, spicy foods, fruit (fructose intolerance); sorbitol intolerance.
  • Esophagitis
  • Esophageal achalasia
  • Esophageal diverticulum
  • Esophageal ulcers
  • Celiac disease (gluten-induced enteropathy) – disease of the mucosa of the small intestine (small intestinal mucosa) due to hypersensitivity to the cereal protein gluten.

Neoplasms – tumor diseases (C00-D48).

  • Gallbladder carcinoma
  • Gastric carcinoma
  • Esophageal carcinoma
  • Pancreatic Cancer

Psyche – nervous system (F00-F99; G00-G99)

  • Anxiety disorders
  • Depression
  • Psychosomatic disorders

Symptoms and abnormal clinical and laboratory findings not elsewhere classified (R00-R99).

  • Meteorism
  • Pyrosis (heartburn)

Laboratory diagnoses – laboratory parameters that are considered independent risk factors.

Medication

  • ACE inhibitors
  • Calcium antagonists
  • Iron supplements
  • Gucocorticoids
  • Methylxanthine
  • Non-steroidal anti-inflammatory drugs (NSAIDs or NSAs; also called non-steroidal anti-inflammatory drugs (NSAPs) or NSAIDs.