What are the differential diagnoses for abdominal pain by region?

Let’s break down the most common differential diagnoses for abdominal pain by the nine abdominal regions.

Keep in mind that both the anatomical regions and quadrants of the abdomen are helpful when correlating anatomical structures within those areas. You can choose which you prefer to use (e.g., regions or quadrants) since both are used throughout medical terminology. But, in this article we will use the nine anatomical regions.

In the right hypochondriac region, pain and tenderness can be associated with gallbladder diseases such as cholelithiasis or cholecystitis. These patients can present with right upper quadrant (RUQ) pain after eating fatty foods.

Duodenal ulcers are associated with pain in the RUQ and right hypochondriac region. Classically, this pain decreases with food or antacids.

Hepatitis and other hepatobiliary diseases such as cirrhosis, hepatoma (e.g., cancer of the liver), or cholangitis (e.g., infection of the bile duct system) also present with pain and tenderness in this region. They are often associated with elevated bilirubin, jaundice, and scleral icterus.

Pain and tenderness in the epigastrium may be associated with gastroesophageal reflux disease (GERD) and gastritis. These often present with heartburn, regurgitation, coughing, and even chest pain.

Gastric ulcers can also cause pain in the epigastric region. Classically, the pain is greater with food and is not relieved by antacids.

Pancreatitis often presents with epigastric pain associated with nausea, vomiting, and anorexia. Common causes of pancreatitis include gallstones, alcohol abuse, and hyperlipidemia. So, be sure to screen for these disorders in your history questions when a patient presents with epigastric pain.

Pain in the left hypochondriac region can occur with GERD, gastritis, or gastric ulcers. As well, a splenic rupture, cyst, or other diseases of splenic etiology can present with pain in this region—which often radiates to the back. These diseases may also involve anemia of thrombotic origin which can lead to a physical exam finding of splenomegaly.

Pain in the right lumbar region can be related to hepatitis or even mesenteric ischemia affecting the loops of the small bowels. Patients often present with pain that seems out of proportion to the exam.

The etiology of mesenteric ischemia is often vascular in nature and can be embolic, thrombotic, or nonocclusive ischemia. Embolic ischemia is usually a sudden onset of pain, while thrombotic and nonocclusive ischemia pain can be chronic or gradual in development.

Inflammatory bowel diseases such as Crohn’s disease often affects the terminal ileum first, which is why it can also present as pain in the right lumbar region. These patients often present with diarrhea and weight loss as well.

A patient with small bowel obstruction often presents with pain, nausea, vomiting, and a lack of bowel movements and flatus. Pertinent history questions can help identify previous surgeries that may be the cause of common etiologies such as adhesions, hernias, or masses.

Pain in the umbilical region may be associated with pancreatitis or peptic ulcer disease, including gastric and duodenal ulcers. It may also be associated with mesenteric ischemia or small bowel obstruction.

During inspection and palpation, also evaluate for an umbilical hernia. If the hernia cannot be reduced, it is likely incarcerated and will need a surgical consult.

Enteritis (e.g., inflammation of the small intestine), which may be caused by several etiologies (e.g., bacterial, viral, or autoimmune issues), can also present with umbilical region pain. These patients often present with nausea, vomiting, and diarrhea. It is important to ask about recent meals and if any of the patient’s contacts are also sick since bacteria in contaminated foods is a common cause of enteritis.

Early appendicitis can also present with periumbilical pain, which later localizes to the right lower quadrant or right iliac region.

In the left lumbar region, you may again encounter pain of splenic etiology, mesenteric ischemia, enteritis, or small bowel obstruction.

Regarding the right iliac region, patients may present with an acute onset of migratory lower right quadrant pain as well as anorexia, nausea, and vomiting, which are concerning for appendicitis.

As well, right-sided inguinal hernias can present with pain in the right iliac region. The first sign is often a bulge in the inguinal region.

Inspect and palpate the hernia to determine if it is incarcerated or strangulated. It may present with signs of an obstruction if the intestines are incarcerated. If the patient has a right-sided inguinal hernia and obstructive symptoms such as nausea, vomiting, anorexia, pain, or constipation, the hernia may contain part of the cecum which is causing the obstruction.

Pain in the hypogastrium (e.g., suprapubic region) could be caused by appendicitis or diverticulitis. However, diverticulitis may start with pain in the lower left quadrant if it involves the sigmoid and left colon.

Ischemic colitis often presents with pain and bright red rectal bleeding from a vascular etiology such as mesenteric ischemia. The left colon is commonly associated with ischemic colitis because of watershed areas found near the splenic flexure in the distal transverse colon and in the upper rectum.

Cystitis or a urinary tract infection can also cause pain in the hypogastric region.

Pain in the left Iliac region is commonly caused by diverticulitis, an inguinal hernia, and ischemic colitis.

As mentioned, the first sign of an inguinal hernia is often a bulge in the inguinal region. If a left-sided inguinal hernia presents with symptoms such as nausea, vomiting, anorexia, pain, or constipation, the hernia may be strangulating the sigmoid colon and causing an obstruction.

Inflammatory bowel disease (specifically ulcerative colitis) can also present here because it tends to affect the rectum first. It often presents with bloody diarrhea, pain, fever, and weight loss.

Right and left hypochondriac pain

Pain in the left and right hypochondriac regions may occur with pulmonary or cardiac causes such as pneumonia, a myocardial infarction, or a pulmonary embolism. These may also present as chest pain and shortness of breath.

Epigastric and umbilical pain

A ruptured aortic aneurysm may present with sudden chest and abdominal pain in the epigastric and umbilical regions.

Left or right lumbar pain

Sudden and colicky flank pain in the left or right lumbar region alongside fever and / or dysuria (e.g., painful or difficult urination) can be caused by nephrolithiasis (e.g., kidney stones) or pyelonephritis (e.g., kidney infection).

Bilateral iliac pain

Pain in the left and right iliac regions can represent ovarian torsion or ovarian cysts in females. Pain in these two areas can also be caused by testicular torsion in males.

That’s it for now. If you want to improve your understanding of key concepts in medicine, and improve your clinical skills, make sure to register for a free trial account, which will give you access to free videos and downloads. We’ll help you make the right decisions for yourself and your patients.