Diagnosis

Splenic abscess

Etiology

Cause [esf]

Contamination of the spleen in a patient with risk factors such as immunosuppression

• Bacteria: Staphylococcus, Streptococcus, Klebsiella, Pseudomonas, Salmonella (typhoid fever), Escherichia coli, Mycobacterium tuberculosis, Proteus mirabilis, Bacteroides fragilis, Clostridium difficile, Serratia marcescens, Enterococcus faecalis

• Fungus: Candida, Aspergillus, Cryptococcus

• Parasite: Malaria (less frequent)

• Virus: Epstein-Barr virus (mononucleosis)

Pathophysiology [ria][nnh][akb][t2z][esf]

1. Hematogenous dissemination

   • Sepsis, endocarditis, pneumonia, ototis media, osteomyelitis, urinary tract infection, diverticulitis, appendicitis, melioidosis, Typhoid fever colitis, tuberculosis, dental extractions

2. Contiguous spread from nearby structures

   • Pancreatic/subphrenic abscesses, gastric/colonic perforations, pneumonia, pneumothorax, empyema, pulmonary embolism, and nephroureterolithiasis

3. Direct contamination

   • Trauma

   • Surgery (superinfected hematoma)

   • Infected splenic infarction (thalassemia, sickle cell anemia, leukemia, catheter embolization)

4. Systemic infection --> microbe collections are transferred to the spleen ("lymph node")

5. Immunosuppresion reduce the capacity of the spleen to manage microbial intruders

6. Contiguous spread occurs through microperforations and dissemination of microbes

7. The formation of a splenic abscess

Risk factors [esf]

• Immunodeficiency:

  • HIV

  • Diabetes mellitus

  • Immunodeficiency syndrome

  • Immunosuppressive therapy

  • Transplant patients

  • Malignancy (lymphoma)

  • Chemotherapy

  • Kidney failure

  • Cirrhosis

• Endocarditis

• Pancreatitis

• Inflammatory bowel disease (Morbus Crohn, Ulcerative colitis)

• IV drug use/alcoholism

Other lesions of the spleen [ria]

• Posttraumatic: Pseudocyst

• Inflammatory: Hydatid (parasitic) cyst

• Congenital: Epidermoid/mesothelial/dermoid cyst

• Vascular: Post-infarction, peliiosis

• Benign neoplasms: Hemangioma, lymphangioma

• Malignant neoplasms:

  • Primary: Mucinous cystadenocarcinoma, primary splenic lymphoma

  • Metastatic: Melanoma, breast, ovarian, gastric, colon, pancreatic cancer

Complications [esf]

• Splenic rupture --> Hemorrhage

• Septic shock

• Left-sided pleural effusion

• Splenic artery/vein thrombosis

• Subphrenic abscess

• Complication to splenectomy:

  • Viscus perforation

  • Pancreatic fistula

  • Pancreatic duct injury

  • Postsplenectomy thrombocytosis

  • Pneumonia

  • Pneumothorax

Epidemiology

Incidence per 100.000 [ria][gq6][t2z][akb][esf][gsv][ukd]

Approach

• Blood test: CBC with differential, erythrocyte sedimentation rate, CA 19-9, CEA, IGRA

• Blood culture

• Ultrasound abdomen

• CT abdomen (the gold standard)

• MRI

• Echocardiography

Treatment

1. Antibiotics [ria][t2z][esf]

2. Percutaneous drainage: <3 cm and few septations (unilocular or bilocular)

3. Surgery: >3 cm

   • Spleen-preserving procedure: partial splenectomy, marsupialization, fenestration

   • Splenectomy

Differential diagnoses

Diverticulitis, HIV, Hydronephrosis, Immunodeficiency, Leukemia, Lymphoma, Pleural empyema, Pneumonia, Pneumothorax, Pulmonary embolism, Pyelonephritis, Pyonephrosis, Sickle cell disease, Thalassemia, Urolithiasis