Imaging features of Mycobacterium avium-intracellulare complex (MAC) in children with AIDS

Purpose. The purpose of this paper was to review the imaging features of Mycobacterium avium-intracellulare complex (MAC) in 16 pediatric patients with human immunodeficiency virus (HIV).¶Materials and methods. We reviewed the pertinent clinical records of 16 children diagnosed with MAC between January 1990 and June 1998. These 16 cases were blood- or biopsy-proven to have MAC infection. Their plain films, abdominal, and chest CT scans were then reviewed and the findings were analyzed with reference to the few reported cases of children with MAC.¶Results. Abdominal findings: all but one had retroperitoneal adenopathy, mesenteric adenopathy or both. Ten patients had hepatomegaly, while nine patients were found to have splenomegaly. Four patients had nonspecific thickened gallbladder wall, while intestinal wall thickening and thickened stomach folds were identified in six of ten patients. Necrotic, fluid-filled nodes were also found. Chest findings included mediastinal adenopathy, cystic/cavitary lesions and bronchiectasis. One patient developed a fistula between the mediastinal lymph nodes, esophagus, and bronchial tree.¶Conclusion. Pediatric patients with HIV who develop MAC infection may present with massive lymph-node enlargement. This can occur not only in mesenteric and retroperitoneal nodes but also in hilar and posterior mediastinal nodes as well. As in MTB infection, these nodes can break down with development of fistulous tracts to both esophagus and adjacent lung. The major differential diagnostic consideration besides MTB is lymphoma.