Irritable Bowel Syndrome (IBS): This condition is characterized by chronic abdominal pain, bloating, and changes in bowel movements, which can manifest as pain in all quadrants due to the diffuse nature of the gastrointestinal tract involvement.

Gastroesophageal Reflux Disease (GERD): GERD can cause pain in multiple areas of the abdomen due to acid reflux, which may be perceived as pain in all quadrants.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause widespread abdominal pain due to inflammation of the gastrointestinal tract.
Functional Dyspepsia: This condition involves recurring signs and symptoms of indigestion that have no obvious cause, which can sometimes be felt across all abdominal quadrants.

Abdominal Aortic Aneurysm: Although less common, an abdominal aortic aneurysm can cause severe, diffuse abdominal pain and is a medical emergency.
Mesenteric Ischemia: This condition, involving insufficient blood flow to the intestines, can cause severe, diffuse abdominal pain and requires immediate medical attention.
Perforated Viscus: A hole in the wall of the stomach or intestine can lead to peritonitis, causing severe, widespread abdominal pain.

Ehlers-Danlos Syndrome: A group of disorders that affect connective tissues supporting the skin, bones, blood vessels, and many other organs and tissues, which can lead to chronic, widespread abdominal pain.
Porphyrias: A group of disorders that result from a buildup of natural chemicals that produce porphyrin in the body, which can cause severe abdominal pain among other symptoms.
Sickle Cell Crisis: In individuals with sickle cell disease, a crisis can cause episodes of severe pain, including abdominal pain, due to the sickling of red blood cells.