Differential Diagnosis

Given the patient's symptoms, the following differential diagnoses can be considered:

• Single most likely diagnosis
  • Irritable Bowel Syndrome (IBS): This is a common condition characterized by abdominal pain, bloating, and changes in bowel movements, but the patient is not constipated, which still fits within the broad spectrum of IBS symptoms, especially if the patient experiences diarrhea-predominant or mixed IBS.
• Other Likely diagnoses
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause abdominal pain and changes in bowel habits without necessarily causing constipation, dysuria, or frequency changes.
  • Gastroesophageal Reflux Disease (GERD): Although primarily associated with heartburn, GERD can cause abdominal pain and discomfort without affecting bowel habits or urinary symptoms.
  • Functional Dyspepsia: This condition involves recurring signs and symptoms of indigestion that have no obvious cause, which could align with the patient's presentation.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Appendicitis: Early appendicitis might present with non-specific abdominal pain without the typical migration to the right lower quadrant or changes in bowel habits.
  • Ovarian Torsion or Rupture: In females, these conditions can cause severe abdominal pain without urinary symptoms and require immediate medical attention.
  • Intestinal Obstruction: Although this typically presents with severe abdominal pain, vomiting, and changes in bowel habits, early stages might not include all these symptoms.
• Rare diagnoses
  • Chronic Intestinal Pseudo-obstruction: A rare condition characterized by impairment of the muscle contractions that move food, fluid, and air through the intestines, which could present with variable symptoms including abdominal pain without constipation.
  • Eosinophilic Gastroenteritis: A rare condition involving eosinophilic infiltration of the gastrointestinal tract, leading to abdominal pain and other gastrointestinal symptoms.
  • Abdominal Migraine: A condition that can cause recurrent episodes of severe abdominal pain, often accompanied by other symptoms like headache or nausea, but not necessarily changes in bowel habits or urinary symptoms.

Each diagnosis is considered based on the absence of constipation, dysuria, or frequency changes, focusing on conditions that could cause abdominal discomfort or pain without these specific symptoms. The justification for each includes the typical presentation and how it aligns with or diverges from the patient's symptoms.