Clinical History
87-year-old patient with clinical signs of acute abdomen.
Imaging Findings
An 87-year-old patient was admitted to the hospitals emergency department with symptoms of acute abdomen and chest pain. Abdominal pain was increasing during the last two days. Chest pain occurred only recently. Radiographs of the chest and abdomen were performed. Chest X-ray showed emphysema the mediastinum and the lower neck. The pleura showed coarse calcifications lining the diaphragm bilaterally. Some of the lines caused by the calcifications were initially misinterpreted as signs of a partial pneumothorax. Plain film study of the abdomen was of only intermediate image quality and showed air below the diaphragm bilaterally. Retroperitoneal air was suspected but the diagnosis was not conclusive due to image quality. Post-contrast MD-CT (Siemens VolumeZoom, 4x2.5 mm collimation, 120 ml non-ionic contrast media i.v. (370 mg/ml iodine)) of the thorax and abdomen was performed showing pneumomediastinum, pneumoperitoneum and pneumoretroperitoneum. The most caudal presentation of extraluminal air was in the region of the colon sigmoideum. The combined intra- and retroperitoneal distribution of extraluminal air and the parasigmoidal air suggested a perforation of the colon sigmoideum. Multiple extraluminal air fluid levels were detected surrounding the colon sigmoideum and diagnosed as parasigmoidal abscesses. Surgery was performed and the patient recovered well. Histopathology conformed divertivulitis with multifocal perforation and parasigmoidal abscesses.
Discussion
Diverticulosis is present in 35% of 45-year old patients and in 67% of 85-years old patients. Both sexes are affected likewise. Typical primary region of manifestation is the Colon sigmoideum. The rectum is typically spared. CT is to day the method of choice for diagnosis of diverticulitis and perforation (1) and can be used to stage the disease to decide if a patients needs acute or delayed surgery. The initial findings in the present case were cervical and thoracic soft tissue emphysema together with pneumoperitoneum and pneumoretroperitoneum. In general extraluminal air is detected radiographically in only 70% of patients (compared with CT). CT has a sensitivity for intestinal perforation of 85,5%. Hence, there are no more recent studies using multidetector CT. The much smaller slice thickness may help to detect very small amounts of extraluminal air and multiplanar reconstructions may help to differentiate small intra- and extraluminal fluid-air-levels. However, the large amount of extraluminal air permitted its detection already in plain film studies. The manifestations of extraluminal air seen in the present case may occur as a result of perforation of the alimentary tract as well as complication of COPD. However, lower abdominal pain as the leading clinical symptom suggested perforation of the abdominal tract as the reason for emphysema. The combined retro- and intraperitoneal distribution of air limited the diagnosis to a retroperitoneally located organ: Duodenum or Colon. The most caudal manifestation of extraluminal air was adjacent to the sigma showing in the same location extraluminal gas-fluid levels interpreted as parasigmoidal abscesses.
Differential Diagnosis List
Perforated sigma diverticulitis causing mediastinal emphysema
Final Diagnosis
Perforated sigma diverticulitis causing mediastinal emphysema
