
Definition and Causes:
Acute gastritis is a sudden inflammation that occurs for the first time in the gastric mucosa due to the effect of external factors acting as strong stimulants (such as alcohol, stress, dietary indiscretion). It is accompanied by disturbances in gastric function and disorders in the upper and lower digestive organs. Without proper examination and treatment, it may progress to chronic gastritis and gastric ulcers.
Causes of Acute Gastritis:
- Irregular meals and dietary violations.
- Increased consumption of fatty, spicy, fried, salty, and smoked foods, and carbonated beverages.
- Harmful habits: smoking and excessive alcohol consumption.
- Prolonged and unmonitored use of medications (NSAIDs, certain antibiotics, analgesics, and antipyretics).
- Severe psychological stress (mental pressure).
- Drinking hot beverages on an empty stomach (such as coffee).
- Autoimmune and allergic inflammation of the gastric mucosa due to immune system errors and environmental factors.
One of the main reasons for the appearance of acute gastritis (as well as erosion and gastric ulcers) is the bacterium Helicobacter pylori. These bacteria produce various toxins (VacA) and enzymes (such as urease, mucinase, protease, and lipase) that reduce the defensive mechanisms of the gastric mucosa, leading to inflammation under the influence of external attack factors and gastric juice.
Helicobacter pylori can be transmitted by consuming untreated food and water. The bacteria can also be transmitted from an infected person to another through kisses, personal hygiene tools, dirty utensils, shared dishes, and toothbrushes. However, infection does not always occur when living with an infected person: it occurs under specific time and environmental conditions.
Complications such as gastric ulcers, increased pressure inside the stomach, and infections may occur after erosion and gastric cancer, among the reasons for the progression of acute gastritis to a more serious form (called suppurative gastritis).
Symptoms of Acute Gastritis may include:
- Heaviness and discomfort in the upper abdomen, often after eating.
- Decreased or loss of appetite.
- Heartburn.
- Unpleasant taste in the mouth (acidic, metallic, bitter).
- Nausea.
- Belching air or food.
- Vomiting with pieces of ingested food, and debris from saliva and bile.
- Abdominal bloating.
- Digestive system disorders.
- Fever may rise to 37 degrees Celsius.
These symptoms often appear immediately after eating or after 15-20 minutes, and may last up to 6-14 hours. They occur due to a disruption in food digestion due to a lack of specific enzymes involved in digestion, causing a slowdown in the digestion process.
When complications such as gastric ulcers or increased pressure inside the stomach occur, pain may occur.
The mentioned digestive disorders may also be present in other conditions of the digestive system such as gastric ulcers, gallbladder inflammation, pancreatitis, and others. Therefore, they must be clearly distinguished from acute gastritis. This can only be done by a doctor.
Mechanism of Inflammation Formation:
The process of forming acute gastritis is the result of stimulating factors, as mentioned earlier, including the gram-negative bacterium Helicobacter pylori, unbalanced diet, and harmful habits.
Thanks to its shape and spikes, Helicobacter pylori bacteria surpass the body’s defense barrier. By destroying the protective mucous layer of the stomach using exotoxins and enzymes secreted by them, these bacteria advance deep into the mucous layer and adhere to its cells.
After attachment, the urea present in the gastric juice is broken down by the urease enzyme, with the release of ammonia and carbon dioxide gas (CO2). Using ammonia, Helicobacter pylori bacteria neutralize the acidic environment in the gastric juice, causing irritation and inflammation of the mucous layer, thus providing favorable conditions for their survival.

The key factors causing damage to the gastric mucous layer include:
- Direct adhesion of Helicobacter pylori bacteria to epithelial cells (the superficial layer of the mucous).
- Ammonia produced under the influence of urease enzyme.
- Toxins secreted by Helicobacter pylori bacteria that destroy the protective layer of mucus and breach cellular membrane integrity.
- Other bacteria participating in the destruction of the protective cell barrier.
- Penetration of hydrochloric acid and its aggressive effect on inflamed and unprotected areas in the mucous layer.
- Local and systemic inflammation spread.
However, it is understood that the process of forming acute gastritis is not only the destruction of the gastric mucous layer but also an action of the immune system to restore its health. When the mucous layer is damaged, the body produces special substances that activate immune cells to remove harmful substances.
Classification of Acute Gastritis (ICD-10 code: K29)
The classification and stages of development of acute gastritis are based on the depth of damage to the mucosal layer, its spread, causes, and the nature of the inflammation. Here are some forms according to:
- Depth of inflammation: Superficial (up to gastric glands). Deep (all layers of the mucosa).
- Spread: Localized (focal). Accelerated (widespread).
- Cause: Infectious (acute inflammation form of enteric infection, Helicobacter pylori). Non-infectious (sensitivity, chemical, spontaneous).
According to Inflammation:
- Inflammatory (simple) – characterized by redness and swelling of the mucosa. Often occurs due to unhealthy eating. It usually manifests gradually with feelings of heaviness and pressure in the upper abdomen, nausea, belching, heartburn, and unpleasant taste in the mouth. After a while, sharp or chronic pain joins these symptoms. Vomiting occurs in the context of pain.
- Fibrinous (diphtheritic) – a rare type of acute gastritis. It is contributed by severe inflammation and acid poisoning. Its symptoms recur with symptoms of simple acute gastritis. It is characterized by the presence of a gray or yellow-brown layer on the inner walls of the stomach.
- Hemorrhagic – a severe form of acute gastritis. Often associated with chemical damage to the mucosal layer in the stomach, such as ingesting highly concentrated acid or active alkaline or heavy metal salts. Symptoms appear immediately after the stomach is exposed to these substances. The patient suffers from frequent vomiting that does not relieve discomfort. Blood and mucus are found in the vomitus. Signs of cellular necrosis (destruction) appear on the mucosal layer of the stomach.
- Pus-forming (purulent) – often a complication and represents the end stage of acute gastritis. Purulent fusion of the gastric walls occurs, and pus spreads into the tissues beneath the mucosal layer. It is associated with injuries, severe infections, and complications resulting from cancer or gastric ulcers. It develops rapidly and is accompanied by chills, fever, severe weakness, and acute vomiting. Facial features become concentrated.
Complications of Acute Gastritis (ICD-10 code: K29)
Complications usually occur as a result of early diagnosis and timely treatment of acute gastritis. Complications include:
Gastric Ulcers:
- These ulcers represent small damage that appears when the balance between protective factors and external aggressive factors affecting the walls of the stomach is disturbed. Ulcers may be individual and appear suddenly without clear symptoms. In some cases, there may be feelings of fatigue and heaviness in the abdomen after eating. They are difficult to detect based on clinical symptoms and therefore require diagnosis through gastroscopy. Acute ulcers may heal within a month or may cause bleeding. Without treatment, this condition may persist for one month to several years or progress to gastric ulcers.
Gastric Ulcers: - Represent a deeper injury to the mucosal layer in the stomach. Often causes severe pain in the upper abdomen and stomach area. It may complicate with bleeding and perforation in the stomach and require surgical treatment.
Gastric Perforation (Penetrating Ulcer): - Continuous defect in the wall of the stomach, where the contents of the organ leak into the abdominal cavity. Requires urgent surgical treatment.
Gastric Contraction (Outlet Narrowing): - Narrowing of the opening between the pyloric part of the stomach and the beginning of the duodenum, leading to the inability of the stomach to continue digestion. Rarely occurs and often in advanced cases.
Chronic Gastritis: - Chronic inflammation leads to distortion of the basic structure of the gastric mucosal layer, resulting in disorders in stomach function, a decrease in gastric acid secretion, or even its absence, and greatly increases the risk of benign tumors or gastric cancer.
Chronic gastric inflammation disrupts the balance of Helicobacter pylori bacteria and natural infection resistance factors. There may be a lack of defense factors in the human body to destroy these bacteria. This series of events leads to disorders of the function of other digestive organs, where duodenitis and bulbitis, cholecystitis, pancreatitis, and even duodenal ulcers may develop.
Diagnosis of acute gastritis
Diagnosis of acute gastritis involves using a combination of laboratory and diagnostic tests. The diagnosis begins with interviewing and examining the patient. The gastroenterologist clarifies what the patient consumed before the onset of symptoms, the medications they are taking, and whether they suffer from accompanying conditions such as stress, gallbladder, liver, or heart diseases. Objectively, pale and dry skin, tongue coating, rash in the nose and mouth triangle area, gallbladder, and foul mouth odor are noted. During examination (palpation), pain in the upper abdomen area is observed, with the pain shifting to the left or right side of the chest.

Important laboratory tests include:
- Clinical blood analysis.
- 13C urea breath test to detect Helicobacter pylori.
- Chemical blood analysis, which helps in detecting disorders in the pancreas, liver, gallbladder, and their ducts.
Among the more commonly used imaging diagnostic methods are:
- X-ray with contrast using a colored substance, which allows studying the gastric mucosa surface and estimating the degree of tension in the gastric walls.
- Ultrasonography of the stomach, which enables detailed study of the affected areas, but does not allow for taking samples for advanced laboratory tests.
Particular attention deserves the discussion of video-gastroscopy (FGDS) – inserting a thin scope through the esophagus into the stomach. These procedures are considered the optimal method for diagnosing gastric diseases. They are prescribed regardless of the patient’s age. This procedure allows identifying areas and the degree of damage to the mucous membrane, evaluating the risk of internal bleeding, and early detection of malignant tumors.
Video-gastroscopy is particularly useful due to the possibility of performing a biopsy – taking a small section of tissue from different parts of the stomach. These procedures are painless and cannot cause bleeding.
Treatment of acute gastritis (K29):
The primary goal of treating acute gastritis is to eliminate the causes of the disease and prevent complications. The treatment plan is individually prescribed by the doctor and depends on the causes and severity of the disease.
In the initial stage, the patient is asked to drink 2-3 cups of warm water to cleanse the stomach, followed by inducing vomiting. Then, during the first 12, 24, 48 hours, cold treatment for the upper abdomen is indicated, avoiding food and rest, with the assignment of a mild diet and gradual diversification. Nutrition is returned to its normal state in about 14 days.
Diet accounts for 80% of gastritis treatment, so success depends on the patient’s responsibility. Main dietary rules should be followed, such as consuming properly cooked and boiled food thermally, eating small meals frequently throughout the day, avoiding fatty, fried, spicy foods, as well as alcohol, coffee, and smoking.
The second stage is drug treatment, which includes:
- Gastric protectants: to protect and stimulate the regeneration of the gastric mucous membrane.
- H2 receptor antagonists and proton pump inhibitors: to reduce gastric acid secretion.
- Antacids and coating agents: such as Almagel, Phosphalugel, Maalox, and others.
- Antispasmodics: to relieve gastrointestinal pain.
- Antiemetics: if necessary.
- Intravenous saline delivery: in case of significant fluid loss.
If gastritis is caused by the bacterium Helicobacter pylori, doctors recommend examining for strains susceptible to amoxicillin. Combination therapy may involve using multiple antibiotics along with periodic probiotic adherence.
Cases of acute phlegmonous gastritis require surgical treatment involving opening the stomach (gastric surgery) and draining the purulent infection.
Many patients mistakenly believe that after taking medication for several days, they regain their health. However, gastritis treatment is not possible without continuous adherence to the diet and abstaining from irritants such as certain medications, alcohol, and smoking.
Sources:
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