1. INT 薛乃維 Supervisor: 鄭莉莉醫師
CT Findings of Granulomatous Pneumonitis secondary to Mycobacterium avium- intracellular inhalation AJR:188, April Department of radiology, mayo clinic scottsdale AZ
INT 薛乃維
Supervisor: 鄭莉莉醫師

2. Objective CT feature of “ Hot Tub Lung”
Mycobacterium avium cpmplex (MAC) contaminated water

3. Background Atypical Mycobacterium cause a wide spectrum disease
Immunocompromised pateint
MAC is the most common

4. Background
Classic MAC : olderly ♂, COPD or pulmonary fibrosis, indistinguish from reaction TB
Non classic MAC: elderly ♀, brochiectasis, nodule, or nodular infiltraion
AIDS
Focus on CT findings of pathologically proven MAC-induced “hot tub lung”

5. Material and Method Chart review for
a. Pathologically proven granumatous
pneumonitis
b. Positive culture for MAC
From 1995/1/1~2004/1/7
12 patients ♂
7 ♀
CT image are reviewed by 2 chest radiologist

6. Material and Method Pulmonary function test for the patient
No immunocompromised disease

7. Material and Method
CT done < 1 month of biopsy

8. Material and Method
Parameter: nodule, reticular plague, ground glass, consolidation, honey combing, cyst.
Cephalocaudal and transaxial plane

9. Result
5 ground-glass, 5 solid

11. Result
Air trapping in all 7 cases

13. Inspiratory CT showed bilateral
Ground glass attenuation
Expiratory image showed Air trapping

14. Discussion
Characteristic findings of MAC induced granulomatous pneumonitis
Non specific, overlapping with sub-acute hypersensitivity pneumonitis
sub-acute hypersensitivity pneumonitis is primary diagnosis
Air trapping is explained by centrilobular granulomas aggravation

15. Discussion
Centrilobular nodule and random ground-glass, the most common findings
Diffuse cephalocaudal through out bilateral lung
7 cases have air trapping

16. Discussion
Whether this disease should be treated as granulomatous disease or hypersensitivity is debate
Clinical course is resemble hypersensitivity
Remove patient form contaminated water, without treatment of anti-tuberculosis medication
Some case treated with anti-tuberculosis medication or steroid

17. Conclusion
Regardless of granulomatous or hypersensitivity, be aware of MAC pulmonary Disease
Ground glass attenuation, Centrilobular nodule, air trapping: radiologist should consider MAC-induced pneumonitis

18. Thanks For your attention