Differential Diagnosis for Stomach Pain and Associated Symptoms

The patient presents with stomach pain in the upper and lower regions, sometimes radiating to the sides of the rib cage and back, with a history of blood in stool that has since resolved. Based on these symptoms, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Gastroesophageal Reflux Disease (GERD): This condition is characterized by stomach acid frequently flowing back into the tube connecting the mouth and stomach (esophagus). This backwash (acid reflux) can irritate the lining of the esophagus, causing discomfort. The symptoms of GERD, including upper stomach pain and sometimes back pain due to referred pain, align closely with the patient's presentation.
• Other Likely Diagnoses
  • Peptic Ulcer Disease: This includes both gastric and duodenal ulcers, which can cause upper abdominal pain and, occasionally, lower abdominal pain if the ulcer is large or perforated. The history of blood in stool could indicate a bleeding ulcer, although the absence of current bleeding does not rule out this diagnosis.
  • Irritable Bowel Syndrome (IBS): IBS can cause a variety of symptoms including abdominal pain, changes in bowel movements, and sometimes back pain. The variability in pain location and the previous presence of blood in stool (which could be due to a complication like a hemorrhoid or an IBS-related increase in bowel movement frequency) make IBS a plausible diagnosis.
• Do Not Miss Diagnoses
  • Pancreatitis: Although pancreatitis typically presents with severe, persistent abdominal pain radiating to the back, it is crucial not to miss this diagnosis due to its potential severity and the need for prompt treatment. The pain pattern described could fit pancreatitis, especially if the pain is constant and severe.
  • Gallbladder Disease: Gallstones or cholecystitis can cause right upper quadrant pain that may radiate to the back or right shoulder. While the patient's pain is not strictly localized to the right upper quadrant, gallbladder disease should be considered, especially if the pain worsens after eating fatty foods.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic abdominal pain, changes in bowel habits, and sometimes back pain. The history of blood in stool is particularly concerning for IBD, and this diagnosis should not be missed due to its significant impact on quality of life and the need for specific management.
• Rare Diagnoses
  • Gastric Cancer: Although less common, gastric cancer can present with nonspecific symptoms like abdominal pain and weight loss. A history of blood in stool could indicate a tumor bleeding, making this a diagnosis that, while rare, should be considered, especially in high-risk populations or with persistent symptoms.
  • Splenic Flexure Syndrome: This is a rare condition where the splenic flexure of the colon becomes kinked or twisted, leading to abdominal pain. It's an uncommon cause of abdominal pain but could potentially explain the variable location of the patient's pain.

Each of these diagnoses requires careful consideration of the patient's full clinical picture, including laboratory tests, imaging studies, and potentially endoscopic examinations to determine the underlying cause of their symptoms.