Splenic abscesses, like abscesses elsewhere, are localised collections of necrotic inflammatory tissue caused by bacterial, parasitic or fungal agents. They uncommonly affect the spleen due to its efficient reticuloendothelial system phagocytic activity and, consequently, are more likely seen in immunosuppressed patients.
Splenic abscesses are uncommon, and their incidence in various autopsy series is estimated at ~0.4% (range 0.14-0.7%) 2,15. The frequency may be rising due to a rise in the use of immunosuppressive agents and prevalence of immunosuppressive states, higher survival of leukaemic patients, and high incidence of drug abuse 13,15.
Splenic abscesses often present with vague, non-specific signs. Fever is common 3. Patients may present with left upper quadrant tenderness accompanied by rigors, chills, and vomiting. In most immunocompetent patients, a complete blood count will show marked leukocytosis with a left shift.
The main causes of splenic abscesses include:
- immunodeficiency conditions (e.g. chemotherapy/transplant recipients, leukaemia and AIDS): especially in those with multiple splenic abscesses 11,23
- infection: anaerobes are thought to be the most common infective agents 8
- splenic infarction with superimposed infection
A plain abdominal radiograph is insensitive in the evaluation of splenic abscesses. Indirect signs include gas within the abscess, and a reactive left-sided pleural effusion 3.
Splenic abscesses are typically poorly-demarcated with a variable appearance, ranging from predominantly hypoechoic with some internal echoes to hyperechoic 23. They may contain septa of varying thickness. The presence of gas bubbles may also be seen with reverberation artefact, although the majority of splenic abscesses do not contain gas.
Ultrasound may also be used to guide abscess aspiration 22.
Normally are centrally low-density lesions (20-40 HU 17). Minimal peripheral contrast enhancement may be present once a capsule has developed. Ascites and adjacent pleural effusion can be seen.
May show solitary, multiple, or multilocular intrasplenic lesions. MR imaging characteristics can vary dependent on the size and infectious agent.
Usually, the abscesses are of fluid signal intensity 15,20:
- T1: low signal (T1 signal may increase if there is proteinaceous content)
- T2: high signal
T1 C+ (Gd)
- there can be minimal peripheral enhancement once a capsule develops 15
- larger lesions can also show peripheral and perilesional enhancement 16
The clinical context is vital in interpreting nuclear medicine images.
In some cases, 99mTc-HMPAO leukocyte scans or 99mTc-HIG (human polyclonal immunoglobulin) scans may show one or more intrasplenic defects 5.
111-In leukocyte scans and 67-Ga scans may also show a photophenic abscess cavity 19.
Treatment and prognosis
Traditional treatment for splenic abscess has been splenectomy and antibiotic therapy but image-guided percutaneous aspiration and drainage can also be considered. While many advocate image-guided drainage 9,10, several publications suggest that splenectomy has a better outcome than percutaneous drainage or intravenous antibiotics alone 3,4.
As a broad differential for splenic abscesses, consider other splenic lesions.
- 1. Rabushka LS, Kawashima A, Fishman EK. Imaging of the spleen: CT with supplemental MR examination. Radiographics. 1994;14 (2): 307-32. Radiographics (abstract) - Pubmed citation
- 2. Thanos L, Dailiana T, Papaioannou G et-al. Percutaneous CT-guided drainage of splenic abscess. AJR Am J Roentgenol. 2002;179 (3): 629-32. doi:10.2214/ajr.179.3.1790629 - Pubmed citation
- 3. Green BT. Splenic abscess: report of six cases and review of the literature. Am Surg. 2001;67 (1): 80-5. Pubmed citation
- 4. Tung CC, Chen FC, Lo CJ. Splenic abscess: an easily overlooked disease?. Am Surg. 2006;72 (4): 322-5. Pubmed citation
- 5. Tikkakoski T, Siniluoto T, PäIväNsalo M et-al. Splenic abscess. Imaging and intervention. Acta Radiol. 1993;33 (6): 561-5. Pubmed citation
- 6. Phillips GS, Radosevich MD, Lipsett PA. Splenic abscess: another look at an old disease. Arch Surg. 1998;132 (12): 1331-5. Pubmed citation
- 7. Llenas-García J, Fernández-Ruiz M, Caurcel L et-al. Splenic abscess: a review of 22 cases in a single institution. Eur. J. Intern. Med. 2009;20 (5): 537-9. doi:10.1016/j.ejim.2009.04.009 - Pubmed citation
- 8. Ng KK, Lee TY, Wan YL et-al. Splenic abscess: diagnosis and management. Hepatogastroenterology. 2002;49 (44): 567-71. Pubmed citation
- 9. Taşar M, Uğurel MS, Kocaoğlu M et-al. Computed tomography-guided percutaneous drainage of splenic abscesses. Clin Imaging. 2004;28 (1): 44-8. doi:10.1016/S0899-7071(03)00033-0 - Pubmed citation
- 10. van der Laan RT, Verbeeten B, Smits NJ et-al. Computed tomography in the diagnosis and treatment of solitary splenic abscesses. J Comput Assist Tomogr. 1989;13 (1): 71-4. Pubmed citation
- 11. Caslowitz PL, Labs JD, Fishman EK et-al. The changing spectrum of splenic abscess. Clin Imaging. 1989;13 (3): 201-7. Pubmed citation
- 12. Faught WE, Gilbertson JJ, Nelson EW. Splenic abscess: presentation, treatment options, and results. Am. J. Surg. 1990;158 (6): 612-4. Pubmed citation
- 13. Alonso Cohen MA, Galera MJ, Ruiz M et-al. Splenic abscess. World J Surg. 1990;14 (4): 513-6. Pubmed citation
- 14. Chiang IS, Lin TJ, Chiang IC et-al. Splenic abscesses: review of 29 cases. Kaohsiung J. Med. Sci. 2003;19 (10): 510-5. doi:10.1016/S1607-551X(09)70499-1 - Pubmed citation
- 15. Elsayes KM, Narra VR, Mukundan G et-al. MR imaging of the spleen: spectrum of abnormalities. Radiographics. 2005;25 (4): 967-82. Radiographics (full text) - doi:10.1148/rg.254045154 - Pubmed citation
- 16. Luna A, Ribes R, Caro P et-al. MRI of focal splenic lesions without and with dynamic gadolinium enhancement. AJR Am J Roentgenol. 2006;186 (6): 1533-47. doi:10.2214/AJR.04.1249 - Pubmed citation
- 17. Ros PR, M.D. KJM. CT And MRI of the Abdomen And Pelvis. Lippincott Williams & Wilkins. (2007) ISBN:0781772370. Read it at Google Books - Find it at Amazon
- 18. Johnson JD, Raff MJ, Drasin GF et-al. Radiology in the diagnosis of splenic abscess. Rev. Infect. Dis. 1985;7 (1): 10-20. Pubmed citation
- 19. Ammann W, Chiu BK, Wright JM. Subacute splenic abscess. Appearance on indium-111 leukocyte, gallium-67, and technetium-99m sulfur colloid imaging. Clin Nucl Med. 1986;11 (3): 165-7. Pubmed citation
- 20. Hamm B, Krestin GP, Laniado M et-al. MR Imaging of the Abdomen and Pelvis. Thieme. (2009) ISBN:3131455918. Read it at Google Books - Find it at Amazon
- 21. Bayer AS, Bolger AF, Taubert KA, Wilson W, Steckelberg J, Karchmer AW, Levison M, Chambers HF, Dajani AS, Gewitz MH, Newburger JW, Gerber MA, Shulman ST, Pallasch TJ, Gage TW, Ferrieri P. Diagnosis and management of infective endocarditis and its complications. Circulation. 98 (25): 2936-48. Pubmed
- 22. Ferraioli G, Brunetti E, Gulizia R, Mariani G, Marone P, Filice C. Management of splenic abscess: report on 16 cases from a single center. International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases. 13 (4): 524-30. doi:10.1016/j.ijid.2008.08.024 - Pubmed
- 23. Lee HJ, Kim JW, Hong JH, Kim GS, Shin SS, Heo SH, Lim HS, Hur YH, Seon HJ, Jeong YY. Cross-sectional Imaging of Splenic Lesions: RadioGraphics Fundamentals | Online Presentation. (2018) Radiographics : a review publication of the Radiological Society of North America, Inc. 38 (2): 435-436. doi:10.1148/rg.2018170119 - Pubmed
- normal appearance of the spleen
- pseudolesion of the spleen: inhomogeneous splenic enhancement
splenic lesions and anomalies
- congenital anomalies
- mass lesions
- infiltrative processes
- incidental splenic lesion (approach)