Gastroenterology and Hepatology

Author: Dr. Abhimanu Kumar, CEO, Ramnath Prasad Institute of Higher Education Foundation, Patna

Abstract

Gastroenterology and hepatology encompass the prevention, diagnosis, and management of disorders affecting the gastrointestinal tract, liver, biliary system, and pancreas. These conditions account for a substantial proportion of global morbidity and healthcare utilization, ranging from common functional gastrointestinal disorders to complex inflammatory, infectious, metabolic, and malignant diseases. This chapter provides a comprehensive overview of the anatomical, physiological, and pathological foundations of digestive system disorders, integrating evidence-based clinical practice with advances in diagnostic and therapeutic technologies. It discusses the systematic evaluation of gastrointestinal symptoms, including dysphagia, abdominal pain, dyspepsia, nausea, vomiting, diarrhea, constipation, gastrointestinal bleeding, jaundice, and weight loss, alongside structured history taking and physical examination. Common diseases such as gastroesophageal reflux disease (GERD), peptic ulcer disease, inflammatory bowel disease, irritable bowel syndrome, acute and chronic pancreatitis, viral hepatitis, fatty liver disease, cirrhosis, portal hypertension, gallstone disease, and gastrointestinal malignancies are reviewed with emphasis on their pathophysiology, clinical manifestations, diagnosis, and current treatment strategies. The chapter highlights the role of laboratory investigations, endoscopy, colonoscopy, endoscopic ultrasound, abdominal ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), elastography, and molecular diagnostics in disease evaluation and monitoring. Evidence-based pharmacological therapies, nutritional management, endoscopic interventions, minimally invasive procedures, and liver transplantation are discussed as essential components of comprehensive patient care. Emerging advances in artificial intelligence-assisted endoscopy, precision medicine, microbiome research, non-invasive biomarkers, and targeted biological therapies are also explored for their potential to improve diagnostic accuracy and therapeutic outcomes. By integrating clinical expertise with contemporary scientific evidence, healthcare professionals can optimize patient-centered care for digestive and liver diseases. This chapter serves as a foundational resource for undergraduate and postgraduate medical students, residents, gastroenterology and hepatology trainees, and practicing clinicians committed to delivering high-quality, evidence-based gastrointestinal and liver healthcare.