Abdominopelvic actinomycosis involving the gastrointestinal tract: CT features

Appendecular actinomycosis: A case series of 14 patients

OBJECTIVE

This study aims to assess the clinical, radiological, and histological characteristics of Actinomyces infection identified in appendectomy specimens.

MATERIAL AND METHODS

Between January 2013 and November 2023, 5834 patients underwent appendectomy in our clinic, and their pathology reports were retrospectively reviewed.

RESULTS

Actinomyces appendicites were reported in 14 specimens (0.23%). It was determined that appendectomy was performed in only 10 patients (71.4%), ileocecal resection was performed in two patients (14.2%) and right hemicolectomy in two patients (14.2%). The operations on five patients were performed by laparoscopy, and the operations on the other nine patients were performed by open surgery. Laparoscopy was started in three patients and converted to open surgery due to suspicion of an ileocecal mass and cecal perforation. It was found that the white blood cell count of three patients was within the normal range of reference (8-9.77mg/dL); leukocytosis was detected in other patients (10.2-18.7mg/dL). C-reactive protein was normal in one patient and high in the rest of the patients. While the first-hour erythrocyte sedimentation rate was normal in five patients, it was found to be high in the other patients. Findings on radiological imaging were reported as acute appendicitis, appendicular plastron, and ileocecal mass. As a result of the pathology findings, the patients were given oral penicillin or semi-synthetic penicillin derivatives during one month.

CONCLUSION

Ileocecal and appendecular actinomycosis are rare, and preoperative diagnosis is difficult. A definitive diagnosis is usually made after a histopathological examination. After surgery, long-term antimicrobial treatment of the patient is possible with penicillin.

Appendiceal actinomycosis mimicking malignant tumor: a rare case report

Introduction

Actinomycosis is an uncommon bacterial infection caused by Actinomyces bacteria that typically progresses slowly and leads to the formation of masses. Although it commonly affects the cervicofacial area, about 20% of cases occur in the abdominopelvic region. Because the disease can be mistaken for a tumour due to its infiltrative mass-like nature on imaging, over 90% of cases are only diagnosed following surgery and histological confirmation. This report describes a case of an appendicular mass, initially suspected to be a malignant tumour, but eventually diagnosed as appendiceal actinomycosis.

Presentation of case

Upon initial presentation, a 53-year-old woman with type II diabetes mellitus and no prior surgical history, displayed abnormal appendiceal uptake during a PET-computed tomography (CT) scan conducted for a suspected spinal tumour. Colonoscopy did not indicate any notable observations, and the patient chose to defer immediate action. Several months later, a CT scan revealed an increased mass-like appearance of the appendix compared to the previous PET-CT scan. After multidisciplinary discussions, a right laparoscopic hemicolectomy was recommended due to suspected malignancy. However, histological staining on microscopy confirmed actinomycosis originating from the appendix.

Discussion

Chronic appendicitis with radiologic features similar to appendiceal carcinoma, or abdominal masses located in the ileocecal area, in patients with or without a previous surgical history should raise suspicion of actinomycosis.

Conclusion

Appendiceal actinomycosis should be considered in the differential diagnosis in the aetiology of chronic appendicitis mimicking appendiceal carcinoma. Awareness and accurate diagnosis of appendiceal actinomycosis can prevent unnecessary extended surgery as was performed in this case.

A pictorial review of genitourinary infections and inflammations

Various infectious and inflammatory diseases affect the genitourinary system. This paper provides a review of multiple common and uncommon infectious and inflammatory conditions affecting the genitourinary system and some associated complications. These include acute infectious cystitis, emphysematous cystitis, acute pyelonephritis, emphysematous pyelonephritis, renal and perinephric abscesses, pyonephrosis, xanthogranulomatous pyelonephritis, epididymo-orchitis, vasitis, prostatitis, pelvic inflammatory disease, renal hydatid infection, renal tuberculosis, actinomycosis, Erdheim-Chester Disease, IgG4-Related Kidney Disease, urethritis and urethral strictures, ureteritis cystica, and genitourinary fistulas. Radiologists should be aware of these diseases' complications and management. Uncommon conditions must be considered when evaluating the genitourinary system.

Actinomycosis with Fusobacterium empyema

Actinomyces, are gram-positive, non-spore forming anaerobic or microaerophilic species. Empyema due to actinomycosis is relatively rare and can be difficult to diagnose as the presenting symptoms may be indolent and the micro-organism may be difficult to culture. This case report describes a patient presenting with dyspnoea, weight loss and lethargy. The chest radiograph, CT and thoracic ultrasound revealed a left-sided pleural effusion. A chest drain was inserted under ultrasound guidance. The pleural fluid was macroscopically consistent with pus and microbiology showed growth of gram-positive bacilli, Actinomyces meyeri as well as the Fusobacterium species. The patient was treated with a drainage of the pleural fluid, a prolonged course of antibiotics and made a good recovery. The awareness that the Actinomyces species and the Fusobacterium species through their synergistic interaction may cause empyema, may lead to a timely diagnosis and treatment.

Case report: Colonic actinomycosis - A rare cause of a locally advanced colonic tumour

INTRODUCTION AND IMPORTANCE

Colon cancer is a common malignancy and is often encountered initially as locally advanced disease. However, there are many benign clinical entities that may masquerade as complicated colonic malignancy. Abdominal actinomycosis is one such rare mimic.

CASE PRESENTATION

A 48-year-old female presented with a progressively enlarging abdominal mass with skin involvement and clinical features of partial large bowel obstruction. Computed tomography (CT) revealed a mid-transverse colonic lesion at the centre of an inflammatory phlegmon. At laparotomy, the mass was found to be adherent to the anterior abdominal wall, gastrocolic omentum, and loops of jejunum. En block resection was performed with primary anastomosis. Final histology showed no evidence of malignancy, but mural abscesses containing pathognomonic sulphur granules and actinomyces species.

CLINICAL DISCUSSION

Abdominal actinomycosis, particularly of the colon, is rare and exceptionally so in immunocompetent patients. However, the clinical and radiographic presentation often mimics more common conditions such as colon cancer. Accordingly, surgical resection is typically radical to clear margins, and diagnosis is made only on final histopathology.

CONCLUSION

Colonic actinomycosis is an uncommon infection but the diagnosis should be considered particularly in colonic masses with anterior abdominal wall involvement. Oncologic resection remains the mainstay of treatment and the diagnosis commonly made retrospectively given the rarity of the condition.

Pseudo tumor pelvic actinomycosis revealed by colonic obstruction with hydronephrosis: Can extensive surgery be avoided? A case report

Pelvic actinomycosis with an intrauterine device accounts for approximately 3% of all actinomycoses. It is a chronic infectious disease characterized by infiltrative, suppurative, or granulomatous inflammation, sinus fistula formation, and extensive fibrosis, and caused by filamentous, gram-positive, anaerobic bacteria called Actinomyces israelii. The slow and silent progression favors pseudo tumor pelvic extension and exposes the patient to acute life-threatening complications, namely colonic occlusion with hydronephrosis. Preoperative diagnosis is often difficult due to the absence of specific symptomatology and pathognomonic radiological signs simulating pelvic cancer. We discuss the case of a 67-year-old woman who complained of pelvic pain, constipation, and weight loss for 4 months, and who presented to the emergency department with a picture of colonic obstruction and a biological inflammatory syndrome. The computed tomography scan revealed a suspicious heterogeneous pelvic mass infiltrating the uterus with an intrauterine device, the sigmoid with extensive upstream colonic distension, and right hydronephrosis. The patient underwent emergency surgery with segmental colonic resection and temporary colostomy, followed by antibiotic therapy. The favorable clinical and radiological evolution under prolonged antibiotic therapy with the almost total disappearance of the pelvic pseudo tumor infiltration confirms the diagnosis of pelvic actinomycosis and thus makes it possible to avoid an extensive and mutilating surgery with important morbidity.

Pelvi-abdominal as a complication of long-term use of intrauterine device (IUD). The important role of imaging in diagnosis and follow-up

ACTINOMYCOSIS is a rare chronic granulomatous disease caused by anaerobic filamentous gram-positive bacteria, the most common of which is Actinomyces israelii. Actinomycetes are commensal inhabitants of the oral cavity and gastrointestinal tract, but they may become pathogenic through invasion of breached or necrotic tissue. Pelviabdominal ACTINOMYCOSIS is uncommon and can mimic a variety of disease processes, including abdominal mass mimicking malignancy, acute abdomen, asthenia, and weight loss. We describe a 38-year-old woman who presented with acute abdominal pain and tenderness, as well as constitutional manifestations and elevated inflammatory markers. On initial computerized tomography (CT) and MRI, a large fluid collection underlining the anterior abdominal wall at the false pelvic cavity, as well as parietal peritoneal enhancement and smudging of the mesenteric fat and a bulky fibroid uterus with an implanted IUD, were identified. The ultrasound guided aspiration and anaerobic culture revealed positive growth for Actinomyces bacteria. An exploratory laparoscopy revealed extensive adhesions between the abdominal wall and the small intestine, as well as hyperemic and thickened peritoneum, and peritoneal biopsy confirmed ACTINOMYCOSIS. After the diagnosis was established, the IUD was removed and the patient was given Ceftriaxone 2 gm once daily for 6 weeks before switching to oral doxycycline 100 mg twice daily for another 3 months. A significant regression of the suprapubic fluid collection, and peritoneal-mesenteric changes were confirmed on follow-up. The case is discussed, and the relevant literature reviewed and analyzed.

Abdominal actinomycosis mimicking a transverse colon malignancy: a case report and review of the literature

Background

Actinomycosis is a rare inflammatory bacterial disease caused by Actinomyces species which can infrequently affect the large intestine. Disseminated actinomycosis is reported as a rare complication associated with intrauterine devices. We report a case of intra-abdominal actinomycosis mimicking a transverse colon malignancy.

Case presentation

A previously healthy 40-year-old Sinhalese woman was evaluated for intermittent colicky left-sided abdominal pain for 2 months’ duration. Computed tomography of the abdomen showed a circumferential thickening of the wall and narrowing of the lumen of the descending colon with evidence of extraluminal extension to the adjacent parietal peritoneum and abdominal wall suggestive of a stage IV neoplasm. An exploratory laparotomy with extended left hemicolectomy was performed. Macroscopic evaluation revealed a mass lesion with multiple abscesses attached to the transverse and descending colon. Histology was suggestive of actinomycosis with no evidence of malignancy.

Conclusions

Abdominal actinomycosis should be considered in a young patient with chronic abdominal pain. It should be understood that the presentation may be vague and highly variable. Computed tomography-guided biopsy/fine needle aspiration or laparoscopy and biopsy may be useful in arriving at a diagnosis and can prevent unnecessary surgical intervention.

Hepatobiliary Actinomycosis, a Rare Presentation of a Rare Disease!

Actinomycosis is a chronic granulomatous infection caused by opportunistic bacteria, Actinomyces. These bacteria lack virulence and cause disease when there is a breach in the integrity of the mucosa. Diagnosis of Actinomycosis is challenging and less than 10% of abdominopelvic cases are diagnosed preoperatively. The treatment involves prolonged course of antibiotics with or without removal of tissue. In this case report we will present a case of hepatobiliary actinomycosis which was managed by a combination of both surgical and medical treatment.

Appendiceal actinomycosis mimicking appendiceal tumor, appendicitis or inflammatory bowel disease

Appendiceal actinomycosis is very rare and its diagnosis is often difficult even in surgically resected specimens. Here we report two cases of appendiceal actinomycosis confirmed by pathologic examination of surgically resected specimens. Characteristic histologic features included transmural chronic inflammation with Crohn-like lymphoid aggregates and polypoid mucosal protrusion into cecal lumen through fibrous expansion of the submucosa. Chronic active inflammation involved the mucosa of the appendix and cecum around the appendiceal orifice. Crohn’s disease with predominant cecal involvement and inflammatory pseudotumor were considered as differential diagnoses. Careful examination revealed a few actinomycotic colonies in the mucosa, confirming the diagnosis. A high index of suspicion with awareness of the characteristic histologic features might prompt careful inspection for the actinomycotic colonies, leading to the appropriate diagnosis of this rare disease.

Abdominal actinomycosis misconceived as intestinal lymphoma: Report of a case

INTRODUCTION

Abdominal actinomycosis is a rare clinical entity and it is difficult to make the correct preoperative diagnosis because of its nonspecific clinical symptoms and varied radiological findings. The diagnosis is usually made after the patient undergoes an operation and tissue is available for pathological evaluation. When the diagnosis is made, the patient should be treated with the appropriate long-term antibiotics.

PRESENTATION OF CASE

A 69-year-old male patient was transferred to our hospital complaining of a palpable mass, painful abdominal discomfort, weight loss, and night sweating. After colonoscopy and radiologic studies, our presumptive diagnosis was intestinal lymphoma combined with ileocecal intussusception. He was found to have abdominal actinomycosis after surgery and successfully treated with ampicillin for six months.

DISCUSSION

Pre-operative radiological imaging in abdominal actinomycosis is unlikely to allow a definitive diagnosis, but CT scanning is the single most useful imaging modality. Although we performed preoperative radiological studies, including CT, none led to a diagnosis of abdominal actinomycosis, we mistakenly considered the case as intestinal lymphoma combined with ileocecal intussusception.

CONCLUSION

Physicians should include abdominal actinomycosis in the differential diagnosis when an abdominal mass presents an irregular, infiltrative growth pattern, even though ileocecal intussusception is an extremely rare presentation in abdominal actinomycosis.

A Rare Thermophilic Bug in Complicated Diverticular Abscess

Actinomycosis is a form of painful abscess in the gastrointestinal tract or in deep tissue caused by actinomyces species. They are one of the commensal bacteria in the oral cavity and gastrointestinal tract of humans but can opportunistically cause infection in immunosuppressive hosts through invasion of breached mucosa or necrotic tissue while mimicking malignancy, gastrointestinal tuberculosis, and inflammatory bowel disease. Actinomyces israelii is, by far, the major and most common human pathogen throughout literatures. By virtue of rarity and diagnostic confusion with masquerading malignancies, only 10% of the cases have been diagnosed preoperatively, so as to be able to verge patients from undergoing unnecessary surgical intervention. Herein, we present a rare case of complicated diverticular abscess manifested by Actinomyces meyeri after postoperative tissue diagnosis.

Abdominal and pelvic actinomycosis due to longstanding intrauterine device: a slow and devastating infection

Actinomycosis is a chronic or subacute bacterial infection characterized by large abscess formation, caused mainly by the gram-positive non-acid-fast, anaerobic, or microaerophilic/capnophilic, obligate parasites bacteria from the Actinomyces genus. Although pelvic inflammatory disease is an entity associated with the longstanding use of intrauterine devices (IUDs), actinomycosis is not one of the most frequent infections associated with IUDs. We present the case of a 43-year-old female patient who was referred to the emergency facility because of a 20-day history of abdominal pain with signs of peritoneal irritation. Imaging exams revealed collections confined to the pelvis, plus the presence of an IUD and evidence of sepsis, which was consistent with diffuse peritonitis. An exploratory laparotomy was undertaken, and a ruptured left tubal abscess was found along with peritonitis, and a huge amount of purulent secretion in the pelvis and abdominal cavity. Extensive lavage of the cavities with saline, a left salpingo-oophorectomy, and drainage of the cavities were performed. The histopathological examination of the surgical specimen revealed an acute salpingitis with abscesses containing sulfur granules. Therefore, the diagnosis of abdominal and pelvic actinomycosis was made. The postoperative outcome was troublesome and complicated with a colocutaneous fistula, which drained through the surgical wound. A second surgical approach was needed, requiring another extensive lavage and drainage of the recto-uterine pouch, plus the performance of a colostomy. Broad-spectrum antibiotics added to ampicillin were the first antimicrobial regimen followed by 4 weeks of amoxicillin during the outpatient follow-up. The patient satisfactorily recovered and is already scheduled for the intestinal transit reconstitution.

[Actinomycosis Involving Chronic Pancreatitis: A Case Report with Literature Review]

Actinomycosis is a slowly progressive, chronic infectious disease. It is caused by the genus Actinomyces, which are gram-positive anaerobic bacteria. It presents as a mass-like lesion, composed of bacterial nidus and characteristic granulomatous inflammatory fibrosis. As such, it has frequently been mistaken for a malignancy. Surgical resection is a common procedure in these patients prior to a definite diagnosis. Although actinomycosis can occur in a variety of regions, including oral-cervicofacial, thoracic, and abdominopelvic cavities, the involvement of the pancreas is very rare. We report a case of a 44-year-old male with a symptomatic actinomycosis caused by a mass in the tail of the pancreas. The diagnosis was made using an endoscopic ultrasound-guided fine needle aspiration biopsy without surgical resection. After the treatment with antibiotics, the pancreatic mass was confirmed to be resolved on the follow-up computed tomography.

Spontaneous Bacterial Peritonitis due to Actinomyces Mimicking a Perforation of the Proximal Jejunum

Patient: Female, 42

Final Diagnosis: Spontaneous pelvic-abdominal peritonitis due to actinomyces

Symptoms: Abdominal distension • abdominal pain • acute abdomen • fever • intermenstrual bleeding • nausea • sepsis • septic shock

Medication: —

Clinical Procedure: —

Specialty: Surgery

Abdominal actinomycosis presenting as appendicitis: two case reports and review

Abdominal actinomycosis (AA) is a rare infection caused by filamentous Gram-positive anaerobic bacteria Actinomyces. We report two cases of adults with AA who initially presented with clinical and radiological features of appendicitis. Both patients underwent appendicectomy with histopathology diagnostic for actinomycosis of the appendix and subsequently completed prolonged courses of oral penicillin. AA is a rare differential diagnosis for appendicitis and should be considered especially in patients with a chronic, indolent course and nonspecific abdominal symptoms. A high index of suspicion may avoid unnecessary surgery, as treatment with prolonged antibiotic therapy is very effective.

Case 219: Pelvic Actinomycosis Mimicking Malignant Tumor

A 53-year-old woman presented with a 3-month history of left inguinocrural and lumbar pain and anorexia with weight loss. No fever was reported. The patient had no prior pelvic surgery. Physical examination revealed a palpable nontender mass in the left groin area. There was no bloody or purulent discharge. Laboratory findings revealed inflammation with an increased C-reactive protein level (127 mg/L [1209 nmol/L]), leukocytosis (13 800/mm(3)), and microcytic anemia (hemoglobin level, 7.2 g/dL). Computed tomography (CT), fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT, and magnetic resonance (MR) imaging were performed.

Abdominopelvic actinomycosis: spectrum of imaging findings and common mimickers

BACKGROUND

Actinomycosis is a rare suppurative disease that may mimic other inflammatory conditions on imaging. Its invasive nature may lead to mass formation and atypical presentation thus making accurate diagnosis quite difficult.

PURPOSE

To describe the different aspects of abdominopelvic actinomycosis on cross-sectional imaging and indicate discriminative findings from other inflammatory or neoplastic diseases.

MATERIAL AND METHODS

In our study we analyzed 18 patients (15 women, 3 men; age range, 25-75 years; mean age, 50 years) with pathologically proved abdominopelvic actinomycosis. Contrast-enhanced abdominal computed tomography (CT) had been performed in all patients. Eleven patients had a history of using intrauterine contraceptive devices. Bowel site, wall thickness and enhancement degree, inflammatory infiltration, and features of peritoneal or pelvic mass were evaluated at CT.

RESULTS

The sigmoid colon was most commonly involved. Most patients showed concentric bowel wall-thickening, enhancing homogenously and inflammatory infiltration of pericolonic fat was mostly diffuse. In 11 patients, one or more pelvic abscesses were revealed, while a peritoneal or pelvic mass adjacent to the involved bowel segment was seen in three cases. Infiltration into the abdominal wall was seen in three cases while in one case there was thoracic dissemination.

CONCLUSION

Actinomycosis is related not only to long-term use of intrauterine contraceptive devices and should be included in the differential diagnosis when cross-sectional imaging studies show concentric bowel wall-thickening, intense contrast enhancement, regional pelvic or peritoneal masses, and extensive inflammatory fat infiltration with abscess formation.

Actinomycosis of cecum associated with entamoeba infection mimicking perforated colon cancer

Actinomycosis is a granulomatous disease caused by Actinomyces that mimics other intra-abdominal pathologies especially neoplasms. Correct diagnosis can be rarely established before radical surgery. On the other hand Entamoeba infection affects a considerable number of people worldwide. To our knowledge only one case has been reported to be affected by both organisms. We report a man who has been operated for a mass in the cecum mimicking a perforated colon cancer. Abdominal CT revealed a mass with features of an invading neoplasm. After radical surgery, definitive pathology revealed that the mass was due to actinomycosis associated with Entamoeba infection. The postoperative period was uneventful and the patient was on long-course antibiotherapy. It is important to consider actinomycosis especially in patients with intra-abdominal masses with unusual aggressiveness to prevent unnecessary surgery. However, surgery can be unavoidable especially in the presence of complicated disease or high index of suspicion for malignancy.

Abdominopelvic actinomycosis associated with an intrauterine device and presenting with a rectal mass and hydronephrosis: a troublesome condition for the clinician

Actinomycosis is an uncommon, chronic, granulomatous disease that can be mistaken for a malignant tumor. Abdominopelvic actinomycosis constitutes about 20% of all actinomycosis cases and may mimic malignancy, tuberculosis, or other abdominopelvic inflammatory diseases. This condition is more prevalent in women who use an intrauterine device. We treated a 44-year-old woman who presented with vaginal discharge, right flank pain, dysuria, and difficulty with defecation. She had anorexia and weight loss (8 kg) during the previous 2 months and had a history of intrauterine device use for 12 years. Clinical, radiologic, and endoscopic examinations revealed a rectal mass and right hydronephrosis. Rectal biopsy showed nonspecific colitis. Laparotomy showed a mass that was invading and obstructing the pelvic orifice. Surgery included total abdominal hysterectomy, bilateral salpingo-oophorectomy, appendectomy, low anterior resection, and Hartmann colostomy. Histopathologic evaluation of surgical specimens showed actinomycosis originating from the tubo-ovarian structures and invading the rectal wall. The patient was placed on penicillin for 6 months, and then had closure of the colostomy with no complication.

Infections and infestations of the gastrointestinal tract. Part 1: bacterial, viral and fungal infections

The purpose of this article is to review the imaging findings of various infections affecting the gastrointestinal tract. Barium examinations, computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography all play an important role in the diagnostic workup of gastrointestinal tract infections. Knowledge of differential diagnosis, sites of involvement, and typical imaging features of different infections can help in accurate diagnosis and guide treatment.

Abdominal-pelvic actinomycosis mimicking malignant neoplasm

Abdominal-pelvic actinomycosis is often mistaken for other conditions, presenting a preoperative diagnostic challenge. In a 46-year-old female, computed tomography showed an abdominal-pelvic retroperitoneal mass extending from the lower pole of the right kidney to the lower pelvis. The patient had a 3-year history of intrauterine device. The mass appeared to involve the ascending colon, cecum, distal ileum, right Fallopian tube and ovary, and ureter anteriorly and the psoas muscle posteriorly. The resection of retroperitoneal mass, distal ileum appendicectomy, right hemicolectomy, and right salpingo-oophorectomy was performed. The postoperative period was uneventful. Penicillin therapy was given for six months without any complication. The retroperitoneal mass measured 4.5 × 3.5 × 3 cm, surrounded adjacent organs and histologically showed inflammatory granulomatous tissue, agglomeration of filaments, and sulfur granules of Actinomyces, with positive reaction with periodic acid Schiff. Right tubo-ovarian abscess was present. Abdominalpelvic actinomycosis should always be considered in patients with a pelvic mass especially in ones using intrauterine device.

Hypervascular subepithelial gastrointestinal masses: CT-pathologic correlation

Although the vast majority of gastrointestinal (GI) masses are epithelial neoplasms, a variety of subepithelial masses are infrequently encountered during endoscopic or radiologic examination. A subepithelial mass, which was previously called a submucosal mass, is defined as a mass covered with normal-appearing mucosa, whether the underlying process is intramural or extramural in origin. At contrast material-enhanced computed tomography (CT), hypervascular subepithelial masses are usually detected more easily than isoattenuating or hypovascular masses. Entities that appear as intramural hypervascular subepithelial lesions include neuroendocrine tumors, GI stromal tumor, glomus tumor, hemangioma, angiosarcoma, Kaposi sarcoma, nerve sheath tumors, hypervascular metastases, heterotopic tissues, and vascular structures. Entities that appear as extramural hypervascular subepithelial lesions include Castleman disease, solitary fibrous tumor, inflammatory myofibroblastic tumor, and actinomycosis. Some rare gastric cancers resemble subepithelial tumors. In comparison with endoscopic ultrasonography, CT is of limited value in differentiating the layers of the GI wall and determining the origin of mass lesions. However, recent advances in multidetector CT with multiplanar reformation allow one to determine whether a GI mass is of epithelial, intramural subepithelial, or extramural subepithelial origin. Furthermore, the full extent of tumors can be delineated, and local invasion and distant metastases can be identified. Familiarity with the characteristic CT appearances of hypervascular subepithelial masses of the GI tract will help radiologists make a more confident diagnosis.

[Actinomycosis as a complication of intrauterine device use]

BACKGROUND

Infections in the female pelvis can present clinically in various ways and the causing agent can be difficult to trace. In this paper we present updated knowledge about infections caused by the bacterium Actinomycosis in relation to intrauterine device use.

MATERIAL AND METHODS

The article is based on own clinical experience and literature identified through a non-systematic search in PubMed.

RESULTS

Actinomycosis in the female pelvis is a rare disease and the pathogenesis is still obscure. The incidence in Scandinavia has not been established. The infection can cause tumor-like structures resulting in bowel and urinary obstruction. The bacteria can be difficult to detect. Preferably the agent should be demonstrated in a specimen from the infected area to ensure the correct diagnosis. However, Actinomyces is a normal inhabitant of the gastrointestinal tract and is also present in 5 % of cervical smears from healthy women. The optimal treatment of actinomycosis is long-term treatment with penicillin, alone or in addition to surgery.

INTERPRETATION

To avoid unnecessary and potentially difficult surgical procedures, actinomycosis should be a differential diagnosis when women with a longstanding intrauterine device develop signs of infection in addition to a pelvic mass. Intrauterine devices should be replaced every fifth year and should be removed at menopause.

Actinomycosis of the appendix mimicking appendiceal tumor: A case report

Actinomycosis is an uncommon chronic infectious disease. Common sites of involvement include the cervicofacial, thoracic and abdominopelvic regions. In abdominopelvic actinomycosis, the ileocecal region, including the appendix, is the most commonly involved site. In some reports, limited appendiceal actinomycosis has revealed a thickened appendiceal wall with peri-appendiceal inflammation as acute appendicitis or perforated appendicitis. We experienced pathologically confirmed intraluminal limited appendiceal actinomycosis without peri-appendiceal infiltration. Here, we report the computed tomography and ultrasound findings.

Actinomycosis: a great pretender. Case reports of unusual presentations and a review of the literature

Actinomycosis is a rare, chronic disease caused by a group of anaerobic Gram-positive bacteria that normally colonize the mouth, colon, and urogenital tract. Infection involving the cervicofacial area is the most common clinical presentation, followed by pelvic region and thoracic involvement. Due to its propensity to mimic many other diseases and its wide variety of symptoms, clinicians should be aware of its multiple presentations and its ability to be a 'great pretender'. We describe herein three cases of unusual presentation: an inferior caval vein syndrome, an acute cholecystitis, and an acute cardiac tamponade. We review the literature on its epidemiology, clinical presentation, diagnosis, treatment, and prognosis.

Case 117: Actinomycosis of Left Kidney with Sinus Tracts

A 39-year-old Samoan man presented to the emergency department with fever, progressive weakness, and left flank pain of 1-month duration. For several months, he had also experienced progressive weight loss. There was no history of recent trauma, and he was not taking any medication. His medical history was notable for a large left groin abscess and left lower lobe pneumonia of unknown cause 1 year prior to the current admission. Furthermore, he had undergone exploratory laparotomy and gastric surgery for peptic ulcer disease approximately 10 years ago. Physical examination findings were positive for a tender firm mass in the left flank with no associated skin changes. Laboratory findings revealed an elevated white blood cell count of 18 x 10(9)/L. The urine cultures were negative. A computed tomographic (CT) image obtained 1 year prior to the current admission was unremarkable. CT of the abdomen and pelvis (section thickness, 5 mm) was performed after ingestion of 900 mL of 2% diatrizoate meglumine and diatrizoate sodium (Gastrografin; Bracco Diagnostics, Princeton, NJ). A 150-mL dose of iohexol (300 mg of iodine per milliliter) (Omnipaque; Nycomed, New York, NY) was administered intravenously at a rate of 4 mL/sec with a 70-second scan delay. Unenhanced CT images (not shown) did not reveal any areas of high attenuation.

Actinomycosis of the gallbladder mimicking carcinoma: a case report with US and CT findings

We describe a case of actinomycosis of the gallbladder mimicking carcinoma. Sonography showed a hypoechoic mass replacing gallbladder lumen and engulfing a stone; contrast-enhanced computed tomography showed a heterogeneously enhanced thickened gallbladder wall with subtle, disrupted luminal surface enhancement, which formed a mass. As a result of the clinical and radiologic presentation, our impression was of gallbladder carcinoma. Actinomycosis should be included in the differential diagnosis when sonography and computed tomography findings show a mass engulfing the stone in the gallbladder and extensive pericholecystic infiltration with extension to neighboring abdominal wall muscle.

The perihepatic space: comprehensive anatomy and CT features of pathologic conditions

The liver is covered by visceral peritoneum except at the bare area, bed of the gallbladder, and porta hepatis. The investing peritoneum becomes contiguous with the adjacent structures such as the diaphragmatic peritoneum, lesser omentum, and ligamentum teres. An inflammatory process or tumors involving the perihepatic space are usually affected by intraperitoneal flow dynamics, which depend on the anatomy of the recess as well as gravity and negative subdiaphragmatic pressure. Pathologic conditions that occur in the perihepatic space include abnormal air, fatty masses, conditions producing fluid attenuation at computed tomography (CT), and soft-tissue masses. Enhancement of the hepatic capsule indicates inflammation, as is seen in Fitz-Hugh-Curtis syndrome. The perihepatic ligaments may be invaded by various conditions by means of direct invasion, subperitoneal extension, or extension along the lymphatic vessels. Knowledge of the normal anatomy of the perihepatic space together with the clinical history and characteristic features at CT can assist the radiologist in making the correct diagnosis.

Abdominal actinomycosis

Abdominal actinomycosis has been recognised for over 150 years yet remains largely unknown to most clinicians. It's varied presentations are usually considered to represent malignancy rather than an infective process - and was once described as 'the most misdiagnosed disease'. Actinomyces are gram positive bacilli of the Actinomycetales genus, and A. israelii is responsible for the majority of human disease. They are normal commensal inhabitants of the human bronchial and gastrointestinal tracts and seem to only cause pathological infection after preceding mucosal breakdown. Patients who have undergone appendicectomy, have had a missed perforated appendicitis or women with a history of intrauterine contraceptive device use are at an increased risk. Florid abscess formation with fistulation, abundant granulation and dense surrounding fibrosis are common. Diagnosis prior to, or even during, surgery is rare and the findings are usually mistaken for acute inflammatory pathologies or malignancy. The treatment of choice is prolonged antibiotic therapy, usually with penicillin to which the organisms remain exquisitely sensitive, although delayed recurrence is possible. This review outlines the historical background of actinomyceal infection and considers the epidemiology, pathophysiology and clinical features of abdominal actinomycosis.