This Comparison Chart displays ten axial chest CT scan slices from a patient with a pulmonary Mycobacterium abscessus infection, illustrating disease progression and treatment response. Panels A-E (top row) represent pre-treatment baseline imaging, while panels F-J (bottom row) show the same anatomical levels following the initial phase of medical therapy. The pre-treatment scans (A-E) demonstrate multiple active pathologies: large thick-walled pulmonary cavities in the right lung (indicated by red arrows in panels C and D) and extensive bilateral 'tree-in-bud' opacities (indicated by blue arrows), which represent centrilobular nodules and branching linear structures characteristic of small-airway impaction and endobronchial spread of infection. In the post-treatment scans (F-J), there is a visible radiological improvement characterized by a significant reduction in the size and wall thickness of the cavities (red arrows in H and I) and a marked decrease in the density and distribution of the tree-in-bud lesions (blue arrows). The image serves as a clinical illustration of antibiotic efficacy in treating nontuberculous mycobacteria (NTM) lung disease, specifically highlighting the resolution of bronchogenic spread and cavitary lesions.

This figure presents two transverse chest computed tomography (CT) scans (axial view) illustrating the progression and treatment response of nontuberculous mycobacterial (NTM) lung disease. Scan (a) shows the initial presentation, characterized by bilateral bronchiectasis and pulmonary consolidations, specifically prominent in the right middle lobe and the lingular division of the left upper lobe (white arrows). Multiple 'tree-in-bud' opacities (black arrow) are visible in the peripheral lung zones, signifying active bronchiolitis and infectious small airway involvement. Scan (b) displays the same anatomical level after 12 months of antibiotic therapy, demonstrating a clear interval reduction in the density and extent of the consolidations (white arrows) and a significant decrease in the tree-in-bud appearances (black arrow). The images illustrate the classic radiographic features of the nodular bronchiectatic form of Mycobacterium abscessus infection and its typical response to targeted pharmacological intervention.

Diagnostic Image: This figure presents multiple axial high-resolution computed tomography (CT) scans of the chest from two different clinical cases of non-tuberculous mycobacteria lung disease (NTM-LD). Panel A (Top): Displays axial slices of an immunocompromised patient with Mycobacterium asiaticum infection. Notable findings include severe, extensive varicose bronchiectasis characterized by significant bronchial dilation and bronchial wall (parietal) thickening, highlighted by black arrows. Also visible are areas of centrilobular opacities with ground-glass attenuation, indicating small-airway involvement. Panel B (Bottom): Shows axial slices from a patient with Mycobacterium avium-intracellulare (MAC) complex. The left slice demonstrates focal consolidation and associated bronchiectasis localized to the right middle lobe. The right slice highlights ground-glass centrilobular opacities in the lingula and lower lobes (black arrows). Educational Significance: These images demonstrate typical radiological patterns of NTM-LD, including the 'nodular bronchiectatic' form which often involves the middle lobe and lingula, and the more severe cavitary/varicose form seen in immunocompromised states.

This diagnostic image consists of a 24-panel mosaic (labeled A–X) of axial chest CT scans demonstrating various pulmonary manifestations of Non-Tuberculous Mycobacteria (NTM) infections. The collection illustrates a spectrum of pathological patterns including small pulmonary nodules (prominent in A, B, S, T), patchy ground-glass opacities (E, F, M, W), and dense lobar or segmental consolidation (C, D). Some sections (G, H) show evidence of reduced lung volume and structural distortion, while others (I, J, K, L, R, V) demonstrate post-treatment intervals with relative clearing of parenchymal disease and more distinct bronchovascular markings. The images provide a comparison of disease morphology across different NTM species, such as Mycobacterium avium complex and M. abscessus. Educational focus is placed on recognizing the radiologic hallmarks of chronic mycobacterial lung disease, monitoring treatment response, and identifying the heterogeneity of infectious presentations in different patients.