Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Tuberculoma
- Radiologic Findings
- Figs 1. Chest PA shows mass with eccentric cavity in the right upper lung.
Fig 2-1 & 2-2. Mediastinal window setting of the chest CT scan shows low attenuated mass with peripheral rim enhancement. Small cavities and peripheral air bubbles seen in the mass.
Figs 3-1 & 3-2. Lung window setting of the chest CT shows a CT halo sign (halo of ground-glass attenuation surrounding the nodule).
Tissue from lung, right upper lobe, aspiration cytology;
Atypical squamous cells embedded in inflammatory background; the latter is mainly polymorphonuclear leukocytes, lymphocytes and epitheloid histiocytes;
tuberculoma is the most probable diagnosis.
- Brief Review
- Tuberculoma is a round or oval granuloma caused by acid-fast bacilli, encapsulated by connective tissue [1]. The pathogenesis of tuberculomas is controversial. They may result from a bronchial infection that has been localized and sealed off. A healed, filled-in cavity and a rounded-off,contracted healing tuberculous lesion are the reported possible mechanisms of tuberculoma formation [1,2].
The tuberculomas on CT scans are usually regular and smooth in outline but may have a rough edge. Cavitation in the lesion or surrounding satellite nodule(s) can be seen on CT scans. The lesions are usually low in attenuation and show no or minimal enhancement with administration of contrast medium [3]. Calcification in the tuberculomas is found in 20-30% of the lesions and is usually nodular and diffuse [4]. Rarely, tuberculoma appears with a CT halo sign (halo of ground-glass attenuation surrounding the nodule) in patients with hemoptysis [5].
In recent report about HRCT findings in patients with pulmonary tuberculosis correlating with the degree of smear positivity, a significant difference was found for scores of GGO between smear-positive and smear-negative PTB patients [6]. They also found that a significant correlation between GGO score and the degree of smear positivity, which is compatible with previous studies [7]. GGO in PTB might reflect nonspecific inflammatory change adjacent to an area of consolidation. Even though, this finding may be considered as a significant indicator of tuberculous activity, some reports suggest that GGO might be seen as a sign of insufficient treatment [8].
- References
- 1. Sochocky S. Tuberculoma ofthe lung. Am Rev Tubercle 1958;78:403-410
2. Bleyer JM, Marks JH. Tuberculomas and hamartomas of the lung. AJR 1957;77:101 3-1 022
3. Lee KS, Song KS, Lim TH, Kim PN, Kim IV, Lee BH. Adult-onset pulmonary tuberculosis: findings on chest radiographs and CT scans. AJR 1993;160:753-758
4. Lee KS, Kim HT, Cho WS, Kim PN, Bae WK, Kim IV. Active solitary tuberculoma of the lung: CT and clinical findings. J Korean Radiol Soc 1993;29:1200-1207 (Korean)
5. Gaeta M, Volta 5, Stroscio 5, Romeo P, Pandolfo I. CT 밾alo sign?in pulmonary tuberculoma. J Comput Assist Tomogr 1992;16:827-828
6. Ors F, Deniz O, Bozlar U, Gumus S et al. High-resolution CT Findings in patients with pulmonary tuberculosis: correlation with the degree of smear positivity. JTI 2007;22:154-159
7. Kosaka N, Sakai T, Uematsu H, Kimura H, et al. Specific high-resolution computed tomography findings associated with sputum smear-positive pulmonary tuberculosis. J Comput Assist Tomogr 2005;29:801-804
8. Poey C, Verhaegen F, Giron J, et al. High resolution chest CT in tuberculosis: evolutive patterns and signs of activity. J Comput Assist Tomogr.1997;21:601?07.
- Keywords
- Lung, Infection, Bacterial infection, Tuberculosis,