Differential Diagnosis for RUQ Pain in a 31-year-old Male with Poor Diet

Single Most Likely Diagnosis

• Cholelithiasis (Gallstones): The patient's poor diet, which may be high in fat and cholesterol, increases the risk of developing gallstones. RUQ pain is a classic symptom of gallstones, especially after fatty meals.

Other Likely Diagnoses

• Cholecystitis: Inflammation of the gallbladder, often associated with gallstones, can cause RUQ pain, fever, and leukocytosis.
• Peptic Ulcer Disease: Poor diet and potential stress can contribute to the development of peptic ulcers, which can cause epigastric or RUQ pain.
• Hepatitis: Viral hepatitis or alcoholic hepatitis (if the poor diet includes excessive alcohol consumption) can cause RUQ pain, jaundice, and elevated liver enzymes.

Do Not Miss Diagnoses

• Appendicitis: Although appendicitis typically presents with lower abdominal pain, it can occasionally cause RUQ pain, especially if the appendix is retrocecal. Missing this diagnosis can lead to perforation and severe complications.
• Hepatic Abscess: A rare but potentially life-threatening condition that can cause RUQ pain, fever, and jaundice.
• Cholangitis: Infection of the bile ducts, which can cause RUQ pain, jaundice, and sepsis.

Rare Diagnoses

• Hepatocellular Carcinoma: A rare cause of RUQ pain in a young adult, but possible if there is a underlying liver disease.
• Intrahepatic Cholestasis: A rare condition that can cause RUQ pain, jaundice, and pruritus.
• Budd-Chiari Syndrome: A rare condition caused by thrombosis of the hepatic veins, which can cause RUQ pain, ascites, and liver dysfunction.