CT of the abdominal wall

Recurrent Primary Abdominal Wall Abscess: A Case Report and Review of the Literature

Primary abdominal wall abscess is extremely rare and difficult to diagnose because abdominal wall abscesses usually occur secondary to malignant tumors or inflammatory diseases. We experienced a case of an 80-year-old man with an asynchronous primary abdominal wall abscess with recurrence. Both abscesses were successfully treated with surgical drainage. A patient without any history of cancer or trauma presented to our department with right upper abdominal pain. His laboratory data showed an abnormal high inflammatory response, and computed tomography revealed a 40 × 30 mm mass formed in the rectus abdominis muscle of the upper right abdomen. The mass had no continuity with the surgical scar after cholecystectomy or intra-abdominal organs. Citrobacter diversus was detected in the culture from the mass and any epithelial components were not detected by biopsy. For the diagnosis of primary abdominal wall abscess, the patient underwent surgical drainage because antibiotic treatment was ineffective. The abscess disappeared promptly after the drainage. Thirteen months after the first treatment, another primary abdominal wall abscess was noted in the lower right abdomen. The abscess also promptly disappeared with surgical drainage. Primary abdominal wall abscess is difficult to diagnose because of its rarity. Prompt diagnosis and drainage are important to prevent exacerbation.

[Thoracoabdominal muscle involvement in anti-PL-7 myopathy revealed by whole-body magnetic resonance imaging]

A 33-year-old woman developed progressive weakness in the proximal limbs with myalgia and morning stiffness. Physical examination revealed low-grade fever, heliotrope eyelids and mechanic's hand. On neurological examination, she showed Medical Research Council grade 4 weakness in the shoulder girdle, proximal limb muscles, and grade 4 weakness in the abdominis muscle according to Daniels's scale. Laboratory tests revealed elevated serum creatine kinase (6,824 IU/l) and positive anti-PL-7 antibody. A needle electromyography study detected short motor unit potentials of myogenic pattern with abundant fibrillations and positive sharp waves. Whole-body MRI detected high intensity signals in the muscles of the shoulder girdle, proximal limbs, and thoracoabdominal trunk on short-tau inversion recovery sequence images. We diagnosed her as anti-PL-7 myopathy. After treatments with steroid, immunosuppressant, and immunoglobulin, her symptoms improved and abnormal MRI signals were normalized. Although MRI is known to be useful for detection of asymptomatic muscular inflammation in myositis, thoracoabdominal muscles are generally not covered in routine evaluation. To our knowledge, ours is the first case to detect acute inflammation of the thoracoabdominal muscles in antisynthetase syndrome. The present study suggests that whole-body MRI is useful for comprehensive evaluation of muscular involvement and longitudinal assessment for treatment outcomes.

Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings

OBJECTIVE

To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery.

METHOD

A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules.

RESULTS

Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5%), small nodules (61.5%), small pseudocavitated nodules (23.1 %), nodules (38.5%), pseudocavitated nodules (15.4%), and collections (26.9%). The findings in the abdominal wall were: densification (61.5%), pseudocavitated nodules (3.8%), and collections (15.4%). The intraperitoneal findings were: densification (46.1%), small nodules (42.3%), nodules (15.4%), and collections (11.5%).

CONCLUSION

Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections.

KEY POINTS

• Rapidly growing mycobacterial infection may occur following laparoscopy. • Post-laparoscopy mycobacterial infection CT findings are densification, collection, and nodules. • Rapidly growing mycobacterial infection following laparoscopy may involve the peritoneal cavity. • Post-laparoscopy rapidly growing mycobacterial intraperitoneal infection is not associated with ascites or lymphadenopathy.

[Abdominal wall abscess as the presenting sign in carcinoma of the colon: report of 4 cases]

PURPOSE

We report four cases of unusual presentation of colonic cancer revealed by an abscess of the abdominal wall.

MATERIALS AND METHODS

Our study included 3 men and 1 women ranging in age from 33 to 66 years presenting with abdominal wall abscess (in the left anterior abdominal wall in 2 patients and in the quadratus lumborum muscle in the other 2 patients). Our cases were listed from the departments of radiology and abdominal surgery of Sahloul hospital from 1995 through 2000. Ultrasonography (US) and computed tomography (CT) were performed in all cases; barium enema in three.

RESULTS

US and CT revealed segmental colonic wall thickening (left colon in three patients and right colon in one patient). The diagnosis of colonic cancer was reached by colonoscopy with biopsy in all 4 cases. All of our patients underwent surgical treatment.

CONCLUSION

In this era of newer diagnostic imaging modalities, US and CT must frequently be used in the evaluation of patients with abdominal wall abscess, to depict intra-abdominal infection and especially malignant lesion causing abdominal wall abscess.

CT herniography in the diagnosis of occult groin hernias

AIM

To evaluate the role of computed tomography (CT) after herniography in the diagnosis and management of primary and recurrent groin hernias not detectable on clinical examination.

MATERIAL AND METHODS

Fifty-one patients underwent CT post-herniography over a 6-year period for suspected primary or recurrent inguinal hernia. The herniography and post-herniography CT findings were retrospectively compared with clinical and surgical follow-up. Statistical analysis was performed to assess the role of herniography and CT post-herniography in the primary and recurrent groups.

RESULTS

Of the 51 patients investigated for occult inguinal hernia, 19 had previous hernia repair with possible recurrence. The most common symptom at presentation was groin pain or discomfort (84%). Seventy-five percent in the primary group and 84% in the recurrent group had no findings on herniography or CT. Nine percent in the primary group and 16% in the recurrent group had hernias diagnosed by herniography. CT did not enhance the detection of hernia. Sensitivity for herniography and CT herniography in the primary groin hernia group was 75% as against specificity, which was 100 and 90%, respectively. For the recurrent groin hernias, sensitivity was 60% for herniography and 40% for CT herniography and specificity 100% for both.

CONCLUSION

CT performed post-herniography did not provide any benefit over performing herniography alone in the diagnosis of occult primary or recurrent inguinal hernias.

Abdominal wall hernias: cross-sectional imaging signs of incarceration determined with sonography

OBJECTIVE

The aim of this study was to determine with sonography whether distinct cross-sectional imaging signs exist that may differentiate between incarcerated and nonincarcerated abdominal wall hernias.

SUBJECTS AND METHODS

The sonographic appearance of 149 consecutive abdominal wall hernias was prospectively investigated and correlated with subsequent surgical results. Commercially available 4- to 10-MHz linear transducers and 2- to 5-MHz curved transducers were used to evaluate the hernias.

RESULTS

Surgery revealed 126 nonincarcerated and 23 incarcerated hernias. The sonographic signs suggestive of incarceration that we identified included free fluid in the hernia sac, which was observed in 91% of the incarcerated hernias and in 3% of the nonincarcerated hernias; bowel wall thickening in the hernia, which was detected in 88% of the incarcerated hernias and in none of the nonincarcerated hernias; fluid in the herniated bowel loop, which was detected in 82% of the incarcerated hernias and in 3% of the nonincarcerated hernias; and dilated bowel loops in the abdomen, which occurred in 65% of the incarcerated hernias and in none of the nonincarcerated hernias. These imaging findings allowed the identification of incarceration in all 23 cases and led to a false-positive result in two of 126 nonincarcerated hernias.

CONCLUSION

Cross-sectional imaging signs indicating hernial incarceration included free fluid in the hernial sac, bowel wall thickening in the hernia, fluid in the herniated bowel loop, and dilated bowel loops in the abdomen. Sonography is an appropriate cross-sectional imaging modality for detecting these signs that are helpful in diagnosing patients with atypical clinical presentations.

Abdominal wall haematoma mimicking visceral injury: the role of CT scanning

Four patients are presented who were thought to have sustained visceral injury following blunt abdominal trauma. However, CT demonstrated abdominal wall haematomata and allowed nonoperative management. Similarity between the clinical findings in visceral injury and abdominal wall haematoma can lead to diagnostic difficulty. The cases illustrate the need to consider abdominal wall haematoma as a possible diagnosis in patients with blunt abdominal trauma. The place of CT in making this diagnosis is highlighted.

Abdominal wall abscess--an unusual primary presentation of a transverse colonic carcinoma

Carcinoma of the transverse colon presenting as an abscess of the anterior abdominal wall is a rare occurrence. Such a case is presented, where all investigations failed to show the nature of the lesion. The literature has been reviewed and the pathology that characterizes such lesions, and their management in the light of their favourable prognosis, is discussed. Occult colonic carcinoma should be considered in the differential diagnosis of such abscesses.