Splenic Cysts

Today we discussed a case of an elderly gentleman with 3 weeks of  constitutional symptoms including fevers and night sweats as well as 30# weight loss over the last 6 months who was found to have a large splenic cyst, ultimately culturing out gram negative rods, concerning for abscess (? endocarditis vs. intraabdominal seeding from recent colonoscopy). A few learning points on splenic lesions/cysts:

1) Splenic cysts are the most common focal lesion in the spleen, but are fairly uncommon with about 0.75 per 100,000.

2) Many are asymptomatic and are noted incidentally on imaging, but can present with LUQ pain, left shoulder pain, and occasionally splenomegaly.

3) Etiology is classified into primary and secondary:

  • Primary: typically congenital epidermoid cysts
    • lined by epithelium
    • solitary
    • large with smooth walls, but many have septations
    • calcification is uncommon
  • Secondary may be due to:
    • Hematoma or splenic infarction (from liqufactive necrosis and cystic change); tend to be small without septations
    • Abscess or infection: histoplasmosis, brucellosis, echinococcosis, candidiasis, tuberculosis, related to endocarditis
    • Extension of pancreatic pseudocyst/walled of necrosis
    • Hydratid cyst (echinococcal infection)
    • Cystic metastases