Chapter 38: Common Abdominal Complaints

Common Abdominal Complaints systematically addresses the most prevalent gastrointestinal and abdominal complaints encountered in clinical practice, providing clinicians with frameworks for differential diagnosis and management. Abdominal pain, a frequent chief complaint, requires careful evaluation of pain characteristics including visceral pain from hollow organ distention, parietal pain from peritoneal irritation, colicky pain from obstruction, and burning pain from mucosal injury, with particular attention to vascular emergencies such as mesenteric ischemia, aortic aneurysm, and myocardial infarction. Constipation, the most common gastrointestinal disorder in the United States, stems primarily from inadequate dietary fiber intake and reduced physical activity, classified into functional, motility-based, and secondary categories, with first-line treatment emphasizing dietary modification and bulking agents for long-term management. Diarrhea, defined as stool weight exceeding 200 grams daily, is distinguished into osmotic and secretory types based on pathophysiology and response to fasting, with acute presentations typically viral and chronic presentations suggesting inflammatory bowel disease, celiac disease, or irritable bowel syndrome. Dyspepsia and heartburn, though frequently conflated, represent distinct entities characterized by epigastric discomfort with functional or medication-induced causes versus retrosternal burning from gastroesophageal reflux disease. Jaundice results from bilirubin accumulation due to cholestasis or hepatocellular disease, with diagnostic differentiation achieved through hepatic transaminases and cholestatic enzyme patterns. Melena, presenting as black tarry stools positive for occult blood, indicates upper gastrointestinal bleeding requiring endoscopic evaluation. Nausea and vomiting, commonly caused by gastroenteritis, medication effects, and central nervous system disorders, provide diagnostic clues through vomitus characteristics. Dysphagia, affecting oral, pharyngeal, and esophageal phases, arises from mechanical obstruction or neurological impairment and requires individualized dietary and positional management or enteral support. The chapter emphasizes geriatric considerations, as older adults present with higher frequency of these conditions due to age-related physiological changes and comorbidities affecting motility, intake, and neurological function.