ILIOPSOAS ABSCESS SECONDARY TO PYELONEPHRITIS WITH SUBSEQUENT UNILATERAL SACROILIITIS PRESENTING AS LOW BACK PAIN IN A YOUNG ADULT: A CASE REPORT
DOI:
https://doi.org/10.67214/cgpgnv67Keywords:
Iliopsoas abscess, ; Low back pain, MRSA, Pyelonephritis, SacroiliitisAbstract
Introduction: Iliopsoas abscess is a rare but potentially life-threatening condition. Secondary iliopsoas abscess following pyelonephritis is rarely reported, and contiguous spread to the sacroiliac joint resulting in sacroiliitis is an uncommon complication. Early detection is crucial, as initial symptoms may mimic low back pain, hip or gluteal discomfort, or genitourinary tract infection, often leading to delayed diagnosis.
Case Presentation: We report a case of a young adult who presented with severe low back pain radiating to the right lower extremity. Pyelonephritis was initially diagnosed based on CT imaging and laboratory tests, including blood tests and urinalysis. Almost two months after symptom onset, MRI revealed a unilateral iliopsoas abscess with contiguous involvement of the sacroiliac joint, resulting in secondary sacroiliitis. Methicillin-resistant Staphylococcus aureus (MRSA) was identified as the causative organism. The patient underwent percutaneous core biopsy and culture-guided antimicrobial therapy, leading to complete recovery.
Conclusion: This case underscores the importance of considering retroperitoneal and sacroiliac infections in patients with persistent, immobilizing low back pain, even when laboratory abnormalities are transient. Prompt imaging and timely management are essential to prevent morbidity and mortality associated with iliopsoas abscess and secondary sacroiliitis.
Downloads
References
1. Baronio M, Sadia H, Paolacci S, et al. Etiopathogenesis of sacroiliitis: implications for assessment and management. Korean J Pain. 2020;33(4):294-304.
2. Laur O, Mandell JC, Titelbaum DS, et al. Acute nontraumatic back pain: infections and mimics. Radiographics. 2019;39(1):287-302.
3. Frank D, Neal B, Jacobs A. Iliopsoas abscess due to nephrolithiasis and pyelonephritis. Clin Pract Cases Emerg Med. 2018;2(3):264-265.
4. Sato T, Kudo D, Kushimoto S. Epidemiological features and outcomes of patients with psoas abscess: a retrospective cohort study. Ann Med Surg (Lond). 2021;62:114-118.
5. Wong OF, Ho PL, Lam SK. Retrospective review of clinical presentations, microbiology, and outcomes of patients with psoas abscess. Hong Kong Med J. 2013;19(5):416-423.
6. Llop Vilaltella M, Maldonado Romero V, Guillén Astete C, et al. Sacroiliitis and gluteal abscess secondary to Staphylococcus aureus infection. Reumatol Clin. 2015;11(6):398-400.
7. Lee JH, Shin HS, Yoon CH, et al. Pyogenic sacroiliitis with psoas abscess: a case report. J Korean Acad Rehabil Med. 2008;32(4):465-468.
8. Kim S, Lee KL, Baek HL, et al. A case of acute pyogenic sacroiliitis and bacteremia caused by community-acquired Staphylococcus aureus. Infect Chemother. 2019;51(1):91-96.
9. Lee YC, Li JJ, Hsiao CH, et al. Clinical characteristics and in-hospital outcomes in patients with iliopsoas abscess: a multicenter study. J Clin Med. 2023;12(8):2760.
10. Al-Khafaji MQ, Al-Smadi MW, Al-Khafaji MQ, et al. Evaluating imaging techniques for diagnosing and drainage guidance of psoas muscle abscess: a systematic review. J Clin Med. 2024;13(11):3199.
11. Sah JK, Adhikari S, Sah G, et al. Presentation, management and outcomes of iliopsoas abscess at a university teaching hospital in Nepal. Innov Surg Sci. 2023;8(1):17-22.
12. Benkhadoura MO, El-Mogassabi AH, Mansor SM, et al. Iliopsoas abscess: clinical presentation, management, and outcome. Int Surg J. 2019;6:17-21.
Downloads
Published
Versions
- 04-07-2026 (2)
- 26-06-2026 (1)
Issue
Section
License
Copyright (c) 2026 Tode Vranishkoski, Jasmin Ciriviri, Darko Talevski, Aleksandra Jovanova (Author)
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors retain copyright of their work and grant the Macedonian Journal of Anaesthesia the right of first publication.
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Authors are permitted to enter into separate, additional contractual arrangements for the non-exclusive distribution of the published version of the work, provided that its initial publication in this journal is acknowledged.
