August 21, 2011

Ileal Diverticulitis

Axial CT image shows an ileal diverticulum (arrow) with surrounding inflammation (arrowheads). Thin arrow = normal appendix.
Sagittal CT image again confirms the presence of an inflamed ileal diverticulum. Note a normal cecum.

Facts
  • Two percents of population have small-bowel diverticula
  • These can be congenital or acquired.
  • Acquired diverticula are common in jejunum and terminal ileum. They are mucosal herniation along the mesenteric border.
  • About 6-10% of patients with small-bowel diverticula develop complications (-itis, hemorrhage, obstruction, intussusception)
Imaging
  • CT can show inflammatory change around the diverticulum with mural thickening of the adjacent bowel loops. The appendix and cecum are normal.

Reference:
Gourtsoyiannis NC. Radiologic Imaging of the Small Intestine, 2002.

August 11, 2011

Kaposi's Sarcoma

Axial CT image shows perihilar peribronchovascular thickening (arrows) and several small ill-defined nodules in the peribronchovascular distribution.
Axial CT image shows patchy groundglass opacities and consolidation in the right middle and lower lobes.

Facts
  • Multicentric neoplasm occuring in three distinct clinical settings: classic (middle-aged adults or elderly men with indolent course), endemic (native populations of equatorial Africans) and disseminated forms (AIDS and immunosuppressed recipients of organ transplants)
  • Associated with human herpesvirus type 8
  • Cutaneous manifestations usually precede visceral disease
  • Respiratory disease is a late manifestation of the disease, it can involve trachea, bronchial tree, pleura and lung parenchyma
  • Diagnosis of respiratory disease is often made presumptively based on clinical/imaging appearance and exclusion of other entities. Biopsy is most definitive.
  • Treatment of pulmonary disease almost always involves chemotherapy
Thoracic Imaging Findings
  • Two patterns: interstitial and nodular
  • Interstitial pattern -- septal lines, localized/focal consolidations, perihilar distribution, "flame-shaped" opacities
  • Nodular pattern -- ill-defined nodules of various sizes that may coalesce into areas of patchy consolidation
  • Up to 60% has pleural effusion
  • Up to 16% has hilar/mediastinal lymphadenopathy
Our case: Kaposi's sarcoma, biopsy-proven

References:
Humes HD. Kelley's Essentials of Internal Medicine, 2001.
Parsons PE, Heffner JE. Pulmonary/reespiratory Therapy Secrets, 2002.