What is the management approach for a patient with a splenule (accessory spleen)?

Management of Accessory Spleen (Splenule)

Accessory spleens (splenules) generally require no specific management unless they are causing symptoms or are associated with hematologic disorders that previously required splenectomy.

Identification and Diagnosis

• Accessory spleens are common, usually asymptomatic, congenital foci of splenic tissue found outside the main spleen 1
• Most commonly located near the splenic hilum (approximately 80%), with about 20% found in or near the pancreatic tail 1
• Imaging techniques can detect accessory splenic tissue in up to 12% of splenectomized patients 2
• Diagnostic modalities include:
  • Contrast-enhanced CT scan (gold standard for trauma patients) 2
  • Ultrasound with Doppler (useful for evaluating splenic vascularization) 2
  • 99Tc-labeled heat-damaged red blood cell scintigraphy (specifically identifies functioning splenic tissue) 3, 4
  • MRI (can help differentiate from other lesions)

Management Approach

For Asymptomatic Accessory Spleens

1. No intervention required for incidentally discovered accessory spleens in otherwise healthy individuals
2. Monitoring only with periodic imaging if discovered during evaluation for other conditions

For Accessory Spleens After Previous Splenectomy

1. Evaluation for functional activity:

   • Perform 99Tc-labeled heat-damaged red blood cell scintigraphy to determine if the accessory spleen has significant splenic function 3
   • CT scan to confirm anatomical location and facilitate potential surgical planning 4

2. Management in patients with recurrent hematologic disease:

   • For patients with recurrent immune thrombocytopenia (ITP), autoimmune hemolytic anemia, or other hematologic disorders after previous splenectomy:
     • Consider laparoscopic excision of accessory spleen if both scintigraphy and CT scan demonstrate the accessory spleen 5
     • Try immunosuppressive therapy first before proceeding to surgical removal 3
     • Note that hematologic response to accessory spleen removal may be less effective than the initial splenectomy 5

For Accessory Spleens in Trauma Patients

• Follow the same management principles as for the main spleen based on the World Society of Emergency Surgery (WSES) guidelines 2:
  • Non-operative management for hemodynamically stable patients
  • Surgical intervention only if the patient is hemodynamically unstable or has other indications for surgery

Prevention of Infection After Splenectomy (Including Accessory Spleen Removal)

• Patients who have undergone splenectomy (including accessory spleen removal) require:
  • Vaccination against encapsulated bacteria (S. pneumoniae, H. influenzae, N. meningitidis) at least 2 weeks before elective procedures or 14 days after emergency procedures 6
  • Annual influenza vaccination 6
  • Antibiotic prophylaxis with phenoxymethylpenicillin 250-500 mg twice daily or erythromycin 500 mg twice daily for penicillin-allergic patients for at least 2 years post-splenectomy 6
  • Education about the risk of overwhelming post-splenectomy infection (OPSI) 6
  • Home supply of antibiotics for emergency use 2, 6
  • Medical alert bracelet/card indicating asplenic status 2, 6

Special Considerations

• Intrapancreatic accessory spleens can be mistaken for pancreatic tumors; careful radiological assessment is essential to avoid unnecessary surgery 1
• Post-splenectomy recurrence of hematologic disorders may not always be due to accessory spleens, even when present 3
• Children under 5 years have significantly higher infection risks after splenectomy and require special consideration for antibiotic prophylaxis 6

Monitoring After Management

• For patients with accessory spleens who have undergone surgical removal:
  • Follow-up scintigraphy to confirm complete removal of all functioning splenic tissue 3
  • Regular monitoring of hematologic parameters to assess response to treatment 5, 3
  • Continued infection prevention measures as outlined above 6