Splenic cysts are uncommon fluid-filled sacs that develop within the spleen, an organ located in the upper left abdomen responsible for blood filtration and immune function. Though rare, these cysts can occasionally cause symptoms or complications, making awareness important for Australians.
What Are Splenic Cysts?
Splenic cysts are broadly classified into two types:
- Primary (True) cysts: These have an epithelial lining and are usually congenital, meaning they develop before birth. They arise from the peritoneal mesothelium or trapped mesothelial cells during development. True cysts tend to grow slowly and are often solitary.
- Secondary (False or Pseudocysts): These lack an epithelial lining and typically result from trauma, hemorrhage, infection, or degeneration within the spleen.
A special category includes hydatid cysts, caused by parasitic infection with Echinococcus species, which are rare but clinically significant in Australia due to the presence of livestock and wildlife reservoirs.
How Do Splenic Cysts Present?
Many splenic cysts are discovered incidentally during imaging tests for unrelated issues, as they often cause no symptoms. When symptoms occur, they usually relate to the cyst’s size or pressure on adjacent organs and may include:
- Dull or aching pain in the left upper abdomen or left shoulder (due to diaphragmatic irritation)
- A feeling of fullness or early satiety because of stomach compression
- Nausea or vomiting
- Occasionally, fever or cough if the cyst affects nearby structures
Large cysts (sometimes exceeding 10 cm) can cause more pronounced discomfort and complications.
Diagnosis in Australia
Imaging plays a key role in identifying and characterizing splenic cysts:
- Ultrasound: Typically shows a well-defined, anechoic (dark) lesion within the spleen. Internal echoes may suggest debris or daughter cysts in hydatid disease.
- Computed Tomography (CT): Provides detailed images showing a hypoattenuating, well-demarcated cyst with thin walls. Calcifications, septations, or internal structures may be visible, especially in hydatid or complicated cysts.
- Magnetic Resonance Imaging (MRI): Useful for further characterization, showing low signal intensity on T1-weighted images and high intensity on T2-weighted images consistent with fluid content.
Blood tests may be done to rule out infection or parasitic causes, and tumor markers like CA 19-9 can sometimes be elevated in epithelial cysts.
Treatment and Management
Small, asymptomatic cysts often require no immediate treatment but should be monitored periodically with imaging. Larger cysts causing symptoms or complications may need intervention:
- Surgical removal: Options include partial or total splenectomy or cyst excision, depending on cyst size and location. Minimally invasive laparoscopic surgery is preferred when possible.
- Medical therapy: In hydatid cysts, antiparasitic medications such as albendazole are used alongside surgery.
- Follow-up: Regular imaging and clinical review are important to detect recurrence or complications.
A Case Highlight
A recent Australian case involved a young woman presenting with left upper abdominal pain, fever, and cough. Imaging revealed a giant splenic cyst displacing adjacent organs. Surgical removal was performed successfully, highlighting the importance of thorough diagnosis and multidisciplinary care.
Summary
Splenic cysts are uncommon but potentially significant lesions within the spleen. Most are benign and asymptomatic, discovered incidentally, but larger cysts can cause discomfort and require treatment. Australians diagnosed with a splenic cyst should work closely with their healthcare providers to determine the best management approach, including monitoring or surgery if needed.