Differential Diagnosis for Right Upper Quadrant Pain

The patient's presentation of right upper quadrant pain, fever, anorexia, nausea, vomiting, and a positive Murphy's sign suggests a hepatobiliary origin. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • a. Cholecystitis: The patient's symptoms, including right upper quadrant pain that worsens with inspiration and radiates to the right shoulder, fever, and a positive Murphy's sign, are classic for acute cholecystitis. The patient's obesity and diabetes also increase her risk for gallstones, which are a common cause of cholecystitis.

• Other Likely Diagnoses

  • b. Pancreatitis: Although the patient's pain is primarily in the right upper quadrant, pancreatitis can sometimes present with pain in this area, especially if the pancreatic inflammation is localized to the head of the pancreas. The patient's history of diabetes and potential for gallstones (which can cause pancreatitis if they obstruct the pancreatic duct) also make pancreatitis a consideration.
  • c. Pyelonephritis: This condition, an infection of the kidney, can present with flank pain, fever, and nausea. While the patient's pain is more localized to the right upper quadrant, pyelonephritis could be considered, especially if there's a history of urinary tract infections or other urinary symptoms.

• Do Not Miss Diagnoses

  • Peptic Ulcer Disease: A perforated peptic ulcer can present with severe abdominal pain and can be life-threatening if not promptly treated. The pain can sometimes be localized to the right upper quadrant, especially if the ulcer is located in the duodenum.
  • Hepatic Abscess: Although less common, a hepatic abscess can present with right upper quadrant pain, fever, and systemic symptoms. This diagnosis is critical not to miss due to its potential for severe morbidity and mortality if not treated appropriately.

• Rare Diagnoses

  • Fitz-Hugh-Curtis Syndrome: This is a rare condition characterized by perihepatitis (inflammation of the tissue surrounding the liver) caused by a sexually transmitted infection, typically chlamydia or gonorrhea. It can present with right upper quadrant pain and should be considered in sexually active individuals.
  • Hepatocellular Carcinoma: While extremely rare as an acute presentation, hepatocellular carcinoma can cause right upper quadrant pain if the tumor ruptures or if there's significant bleeding into the tumor. This would be more likely in patients with underlying liver disease.