Ji Young Lee MD, Presenter: Nothing to Disclose

Kyung Soo Lee MD, Abstract Co-Author: Nothing to Disclose

Tae Sung Kim MD, Abstract Co-Author: Nothing to Disclose

Won-Jung Koh, Abstract Co-Author: Nothing to Disclose

Myung Jin Chung MD, Abstract Co-Author: Nothing to Disclose

Chin A Yi MD, Abstract Co-Author: Nothing to Disclose

O Jung Kwon MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To evaluate sequential changes of lung parenchymal lesions in Mycobacterium avium-intracellulare complex (MAC) pulmonary infection at thin-section CT (TSCT) with or without treatment.

The initial and follow-up chest TSCT scans in 48 patients (M: F= 20: 28, aged 41 - 87 years; mean 63 years) with MAC infection were retrospectively reviewed by two chest radiologists. Patients were divided into two groups; treated (21 patients who had received a regimen of clarithromycin, rifampin, and ethambutol) and untreated group (27 patients). The follow-up period ranged from 6 to 23 months (mean, 13 months). We assessed the sequential changes of pulmonary lesions in terms of tree-in-bud opacity (centrilobular small nodule and branching nodular structure), bronchiectasis, nodules with or without cavity (10-30 mm in diameter), lobular consolidation (consolidation of 10-20 mm in diameter with polygonal shape), segmental consolidation, and large cavities (> 3 cm in diameter).

In treated group, 19 (90%) of 21 patients showed improvement, while remaining two (10%) showed no interval change. Of pulmonary lesions, tree-in-bud opacities (14 of 15, 93%), nodules (15 of 16, 94%), lobular consolidations (9 of 10 patients, 90%), segmental consolidation (1/1, 100%), and cavitary lesions (12 of 14, 86%) showed a decrease in their extent, while bronchiectasis (0 of 17, 0%), and volume loss (0 of 11, 0%) did not show any change. Especially, lobular consolidation showed near-complete resolution in five (50%) of 10. In untreated group, 17 of 27 (63%) patients showed progression of pulmonary lesions, while the remaining ten (37%) showed no interval change (p < 0.001, between treated and untreated groups).

MAC pulmonary infection demonstrates improvement with treatment, whereas it shows deterioration without treatment; therefore, although indolent, the disease is a real and progressive disease necessitating antimycobacterial chemotherapy.

Lee, J, Lee, K, Kim, T, Koh, W, Chung, M, Yi, C, Kwon , O, et al, , Mycobacterium Avium-intracellulare Complex Pulmonary Infection: Serial Changes of Pulmonary Parenchymal Lesions at Thin-Section CT with or without Treatment.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4419619.html