Skip to Main Content



Differential diagnosis for abdominal pain based on area of pain. Shown are the regions of the abdomen and the differential diagnosis for pain in each region. Of note, pain does not always localize precisely, so no matter the location of the pain, consider a broad differential diagnosis. Abbreviations: AAA, abdominal aortic aneurysm; IBD, inflammatory bowel disease; IBS, irritable bowel syndrome; SBO, small bowl obstruction; MI, myocardial infarction; PUD, peptic ulcer disease; RUQ, right upper quadrant; RLQ, right lower quadrant; LUQ, left upper quadrant; LLQ, left lower quadrant.


Differential diagnosis:

  • Neuropsychiatric:

    • - Intracerebral: Increased intracranial pressure (ICP) due to malignancy, hemorrhage, abscess, hydrocephalus

    • - Labyrinthine: Labyrinthitis, motion sickness, malignancy

    • - Psychiatric: Anorexia, bulimia nervosa, depression (may be associated with delayed gastric emptying)

  • Cardiopulmonary: Myocardial infarction, congestive heart failure (nausea/early satiety can be early symptoms), post-tussive emesis

  • Gastrointestinal:

    • - Obstructive: Pyloric obstruction, SBO, colonic obstruction, SMA syndrome

    • - Inflammatory: Enteric infections (viral, bacterial), cholecystitis, cholangitis, pancreatitis, appendicitis, hepatitis

    • - Altered function/functional: Gastroparesis, ileus, pseudo-obstruction, GERD, cyclic vomiting syndrome, cannabinoid hyperemesis syndrome

  • Other:

    • - Medications, pregnancy, uremia, DKA/HHS, thyroid disease


  • Definitions/mimics:

    • - Diarrhea: Passage of abnormally liquid or unformed stools at an increased frequency from baseline

    • - Pseudo-diarrhea: Frequent passage of small volumes of stool, often accompanied by tenesmus, sensation of incomplete evacuation, or rectal urgency; commonly associated with IBS or proctitis

    • - Fecal incontinence: Involuntary fecal discharge, usually due to neuromuscular etiologies or anorectal structural etiologies; however, severe diarrhea may aggravate or result in fecal incontinence

  • “Localizing” features: These features may be present, but are non-specific

    • - Small intestine: Watery, large volume, associated with abdominal cramping, bloating, gas; fever, occult blood/inflammatory cells in stool are rare

    • - Large intestine: Frequent, regular, small volume, often painful bowel movements; fever, bloody or mucoid stools, RBCs/inflammatory cells in stool are common

  • Clinical features: See Table 4.3

TABLE 4.3Types of Chronic Diarrhea: Clinical Features, Diagnostics, and Etiologies

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.