Gastroenterologist: diseases of the stomach and intestines

A gastroenterologist is a physician specializing in the diagnosis, treatment, and prevention of diseases of the digestive system: the esophagus, stomach, small and large intestines, liver, bile ducts, pancreas, and adjacent structures. They perform clinical assessments, prescribe laboratory and instrumental tests, perform endoscopic procedures, and coordinate the multidisciplinary care of complex patients. [1]

A physician in this specialty treats both acute conditions— gastrointestinal bleeding, acute pancreatitis, biliary obstruction—and chronic diseases: gastroesophageal reflux disease, chronic hepatitis, non-alcoholic fatty liver disease, and inflammatory bowel disease. The role includes not only therapy but also screening, prevention, and rehabilitation. [2]

A modern gastroenterologist is proficient in outpatient diagnostic methods and endoscopy with therapeutic options: biopsy, polypectomy, endoscopic hemostasis, stenting, etc. He often interacts with surgeons, oncologists, radiologists and nutritionists for a comprehensive approach to the patient. [3]

It's helpful for patients to know that a first visit to a gastroenterologist typically includes a medical history, a simple physical examination, basic testing, and clarification of indications for endoscopy or advanced imaging. This allows for a rapid development of an examination and treatment plan, minimizing unnecessary procedures. [4]

A brief overview of key diseases: what is most common

Gastroesophageal reflux disease presents with heartburn and regurgitation; in the absence of "red signs," an empirical course of proton pump inhibitors is often started, and if ineffective, endoscopy and additional tests are performed. [5]

Peptic ulcer disease is associated with Helicobacter pylori and the use of nonsteroidal anti-inflammatory drugs; the current strategy is diagnosis and eradication of H. pylori when indicated, as well as assessment of the risk of bleeding in patients on NSAIDs. [6]

Inflammatory bowel diseases are painful, systemic and often require long-term monitoring and targeted therapy with immunomodulators and biological agents; current European guidelines set standards for treatment sequence and monitoring. [7]

Liver diseases cover a broad spectrum: viral hepatitis, steatosis, and liver fibrosis. In recent years, the terminology and approach to non-alcoholic fatty liver disease have changed: a new consensus definition of MASLD and treatment recommendations have emerged, including the management of comorbid obesity and the use of new drugs in selected cases. [8]

Colon cancer is an important target for screening: recommended age ranges and methods may vary by country, but the overall goal is early detection of adenomas and cancer to reduce mortality. In the United States and several other countries, screening begins at age 45 for otherwise healthy individuals. [9]

Diagnostics: What tests are needed and when are they needed?

Upper and lower endoscopy remains a cornerstone method for verifying many diagnoses: it allows for visual assessment of the mucosa, biopsy, and therapeutic interventions. Indications range from "red flags" to routine cancer screening or therapeutic interventions. [10]

For H. pylori, a urea breath test, stool antigen test, and biopsy histology are used; after treatment, eradication control is required no earlier than 4 weeks after the end of antibacterial therapy and while observing the time interval without acidity inhibitors. [11]

In the diagnosis of inflammatory bowel disease, the key remains a combination of endoscopy with biopsy, blood inflammatory markers, coprological tests, and, in some cases, CT or MR enterography to assess small intestinal lesions. Current guidelines clearly regulate the sequence of examinations. [12]

Liver disease assessment uses biochemical panels, fibrosis markers, ultrasound elastography and, if necessary, liver biopsy; for MASLD, the emphasis is on identifying and stratifying fibrosis as a major prognostic factor. [13]

Treatment: principles and examples of modern approaches

For reflux, basic management includes lifestyle modifications, proton pump inhibitors, and, if necessary, surgical or endoscopic options in refractory patients. An empirical 8-week course of an acid inhibitor is a common initial step for classic symptoms without "red signs."[14]

Helicobacter pylori eradication is carried out using regimens selected taking into account local resistance; confirmation of clearance of the infection after completion of therapy is strictly recommended. Insufficient eradication increases the risk of ulcer recurrence and some tumor processes. [15]

The management of inflammatory bowel disease relies on a phased approach: corticosteroids to induce remission, immunomodulators and biological agents to maintain and control disease activity; new European guidelines for 2024 have updated the drug selection and response monitoring regimens. [16]

In MASLD, intensive lifestyle modification and management of comorbid conditions remain key. For patients with advanced fibrosis or biopsychosocial factors, new medications and multidisciplinary weight loss programs are available, and jurisdiction-approved drug options are discussed in individual situations. [17]

Screening and prevention: what everyone needs to know

Colon cancer screening is an effective measure to reduce mortality. For adults at normal risk, noninvasive stool tests or colonoscopy are recommended, depending on local programs; some countries recommend starting at age 45. It is important to adhere to individual screening intervals and national programs. [18]

Prevention of viral hepatitis includes hepatitis B vaccination and screening of donors and risk groups. If chronic hepatitis is confirmed, management should follow specialized guidelines, with the goal of therapy being to reduce the risk of cirrhosis and hepatocellular carcinoma. [19]

H. pylori prophylaxis in the general population is not universally recommended, but treatment is indicated when clinically indicated infection is detected and in groups at high risk of complications. Local policies and resources influence practice. [20]

Community-based preventive measures include promoting healthy eating and physical activity to reduce the risk of MASLD, controlling alcohol consumption, and promptly managing metabolic risk factors. These measures are critical to reducing the burden of chronic liver disease. [21]

When to urgently see a gastroenterologist - "red signs"

Urgent consultation is required for severe gastrointestinal bleeding, sudden and significant decrease in vision or consciousness combined with gastrointestinal symptoms, severe jaundice and signs of liver failure, severe and persistent vomiting, or signs of intestinal obstruction. These conditions often require emergency hospitalization. [22]

Patients with rapid weight loss without apparent cause, persistent progressive dysphagia, persistent abdominal pain with signs of peritoneal syndrome and symptoms indicating a possible malignant process should be examined immediately. [23]

It is also necessary to seek immediate medical attention if a patient with pancreatitis has a fever, increasing ascites, or changes in consciousness due to chronic liver disease - this may indicate infectious or decompensatory complications. [24]

If new neurological symptoms occur in a patient with known H. pylori infection or if severe systemic manifestations of the disease are suspected, urgent consultation and multidisciplinary assessment are also indicated. [25]

Tables

Table 1. The role of a gastroenterologist in the healthcare system

Role	Examples of tasks
Diagnostics	Endoscopy, biopsy, visualization
Treatment	Medicines, endoscopic therapy
Prevention	Screening, vaccination, risk control programs
Coordination	Collaboration with surgery, oncology, and dietetics
Education	Informing patients about lifestyle

Table 2. Common diseases and key approaches

Disease	Key diagnostic steps	Main therapeutic principles
GERD	Clinical presentation, empirical PPI, endoscopy if ineffective	PPI, lifestyle modification, surgery when indicated. [26]
Peptic ulcer disease	H. pylori test, endoscopy for bleeding	H. pylori eradication, NSAID control. [27]
IBD	Endoscopy with biopsy, CT/MR enterography	Induction of remission with steroid, maintenance with biologics. [28]
MASLD	Ultrasound, elastography, fibrosis markers	Weight loss, metabolic control, medication in selected cases. [29]
Colon cancer	Colonoscopy, biopsy	Endoscopy for early forms, surgery and oncotherapy in case of progression. [30]

Table 3. Instrumental methods and their purpose

Method	What does it show?	When is it prescribed?
FGDS	Condition of the esophagus and stomach	Dysphagia, bleeding, suspected ulcer
Colonoscopy	Polyps, tumors, inflammation of the colon	Screening, blood in stool, chronic diarrhea
Ultrasound of the liver with elastography	Presence of steatosis and fibrosis	Assessment of MASLD and fibrosis
CT/MR enterography	Small bowel disease, complications of IBD	Suspected stenosis, abscesses
Urea breath test	H. pylori	Confirmation of infection and eradication control

Table 4. Screening recommendations - guidelines

Context	Recommendation
Colonoscopy for common risk	Start at 45 years of age or according to national programs. [31]
Vaccination against HBV	According to national calendars and for risk groups. [32]
H. pylori screening	Treatment when identified and clinically indicated; strategy varies by region. [33]
Assessing fibrosis in MASLD	Elastography or marker panels if risk factors are present. [34]

Table 5. "Red signs" - a reason for urgent treatment

Sign	What to do
Severe gastrointestinal bleeding	Call an ambulance or seek emergency hospitalization.
Persistent vomiting with dehydration	Immediate assessment in the clinic
Sudden severe abdominal pain	Peritonitis screening, surgical evaluation
Rapid development of jaundice and deterioration of consciousness	Urgently to a specialized liver center
Significant weight loss in a short period of time	Complete examination, including oncological

Brief conclusions for the patient and the doctor

1. A gastroenterologist treats a wide range of diseases of the digestive system and combines clinical assessment with modern instrumental methods, including therapeutic endoscopy. [35]
2. For classic GERD symptoms, an empirical course of a proton pump inhibitor for 8 weeks is a reasonable initial step; if there is no effect, further endoscopy is necessary. [36]
3. H. pylori should be diagnosed and eradicated when indicated; confirmation of therapy success is mandatory at recommended intervals. [37]
4. The management of IBD relies on clearly defined regimens with biological agents when needed; the new 2024 ECCO guidelines update the therapeutic sequence. [38]
5. MASLD requires lifestyle interventions as a primary treatment option; new pharmacological approaches are available for patients with advanced fibrosis in selected cases. [39]