Differential Diagnosis for 23y Male with Abdominal Pain and CT Abdomen Findings

The patient presents with abdominal pain, a history of cholecystectomy, obstipation of the colon, and hyperdense renal pyramids on CT abdomen. The differential diagnosis can be categorized as follows:

• Single Most Likely Diagnosis

  • Medullary sponge kidney (MSK) with medullary nephrocalcinosis: This condition is characterized by the presence of small cysts in the renal medulla and is often associated with nephrocalcinosis, which could explain the hyperdense renal pyramids. The patient's age and the specific findings on the CT scan make this a plausible diagnosis.

• Other Likely Diagnoses

  • Nephrocalcinosis due to other causes (e.g., hyperparathyroidism, renal tubular acidosis): These conditions can lead to the deposition of calcium in the renal parenchyma, resulting in hyperdense areas on imaging. The obstipation could be related to a separate issue or to a systemic condition affecting both the kidneys and the gastrointestinal tract.
  • Colon obstruction: Given the obstipation of the colon, a mechanical obstruction should be considered. This could be due to various causes such as adhesions from the previous cholecystectomy, a tumor, or other structural abnormalities.

• Do Not Miss Diagnoses

  • Ureteral obstruction: This could lead to severe consequences if not promptly addressed, including renal failure. The hyperdense renal pyramids could be a sign of obstructive nephropathy.
  • Sepsis or severe infection: Although less directly related to the imaging findings, severe abdominal pain and obstipation could be signs of a severe infection, especially if the patient has a history of recent surgery or other risk factors.

• Rare Diagnoses

  • Primary hyperoxaluria: A rare genetic disorder that leads to excessive oxalate production, causing nephrocalcinosis and renal stones. This condition is less common but should be considered in young patients with unexplained renal calcifications.
  • Other genetic disorders affecting the kidneys and gastrointestinal tract: Conditions such as cystinosis or certain mitochondrial disorders could potentially explain the combination of findings, although they are rare and would typically present with additional systemic symptoms.