Figure 1
Abdominal mass
A large solid mass is seen, invading both the anterior abdominal wall and intraperitoneal space.
Abdominal actinomycosis mass
SectionAbdominal imaging
Case TypeClinical Cases
AuthorsB. Gulek, S. Ugurlu, S.Z. Ziylan
Connected authors
37 years, female
Clinical History
A solid and fixed anterior abdominal mass. CT showed an irregularly contoured, heterogenously enhancing, and aggressive solid mass, which invaded both the anterior abdominal wall and the peritoneum. The mass also had intra-abdominal components, fulfilling all the characteristics of a malignant mass.
Imaging Findings
The patient presented with a tough and fixed mass in her abdomen, which she could palpate easily at her anterior abdominal wall. The initial physical examination revealed a large and solid mass anteriorly.
A computed tomographic (CT) examination was performed, utilising oral and intravenous (iv) contrast medium. This procedure showed an aggressive solid mass with irregular contours, having dimensions of 9cm x 8cm. The mass, which enhanced irregularly with contrast, was located at the right middle-lower quadrant, and was invading both the anterior abdominal muscles and the intraperitoneal compartments, by infiltrating and crossing the peritoneum (Figs 1-5).
Given the very malignant appearance of the lesion, the patient was operated on without delay. The diagnosis on intraoperative inspection of the lesion was also of a malignant growth. The patient underwent a thoroughly extensive operation. However, the pathological diagnosis was actinomycosis. This was an unexpected, surprising result.
Discussion
Actinomycosis is an infection caused by Actinomyces israelii, which is a gram-positive bacterium. It is usually seen in patients with immune deficiency. It can also be encountered in patients with stab wounds (1-5). This case fitted neither of these circumstances, and actinomycosis was a completely unexpected diagnosis. As a result, we conclude that actinomycosis should be considered in the differential diagnosis of aggressive abdominal masses.
Differential Diagnosis List
Abdominal actinomycosis mass
Final Diagnosis
Abdominal actinomycosis mass
References
[1] Meyer P, Nwariaku O, McClelland RN, Gibbons D, Leach F, Sagalowsky AI, Simmang C, Jeyarajah DR. Rare presentation of actinomycosis as an abdominal mass: report of a case. Dis Colon Rectum 2000 Jun;43(6):872-5. (PMID: 10859092)
[2] Molnar T, Nagy A, Ligeti E, Gyulai C, Marton J, Nagy F. Abdominal actinomycosis presenting as a malignant tumor -- report of a case and review of the literature. Orv Hetil. 1999 Oct 31;140(44):2453-6. (PMID: 10573989)
[3] Tlili-Graiess K, Arifa-Achour N, Mrad Dali K, Sriha B, Dahmen Y, Bakir D, Jemni H, Jeddi M. Abdominal actinomycosis. Report of 4 clinical cases studied with radiography. J Radiol 2001 Jan;82(1):67-72. (PMID: 11223633)
[4] Corcione F, Bianco A, Fusco E, Fusco F, Fusco C, Pisaniello D, De Blasio F. Abdominal actinomycosis and retroperitoneal fibrosis. Considerations on a clinical case. Chir Ital 2001 Nov-Dec;53(6):893-8. (PMID: 11824069)
Case information
| URL: | https://www.eurorad.org/case/1937 |
| DOI: | 10.1594/EURORAD/CASE.1937 |
| ISSN: | 1563-4086 |
Figure 2
Abdominal mass
This is a closer look at the mass. Heterogeneously enhanced with contrast, and invading anteriorly and posteriorly, it has an aggressive feature.
Figure 3
Abdominal mass
The mass affects the intraperitoneal compartments.
Figure 4
Abdominal mass
Invasion of the intraperitoneal compartments is better seen in this close-up image.
Figure 5
Abdominal mass
The mass also has intrapelvic infiltrating components.
Abdominal mass
A large solid mass is seen, invading both the anterior abdominal wall and intraperitoneal space.
Abdominal mass
This is a closer look at the mass. Heterogeneously enhanced with contrast, and invading anteriorly and posteriorly, it has an aggressive feature.
Abdominal mass
The mass affects the intraperitoneal compartments.
Abdominal mass
Invasion of the intraperitoneal compartments is better seen in this close-up image.
Abdominal mass
The mass also has intrapelvic infiltrating components.