Clinical investigation of cavitary tuberculosis and tuberculous pneumonia

Abstract

Background: [corrected] The radiographic characteristics of tuberculous pneumonia in adults are similar to primary tuberculosis that occurs in childhood, and upper lobe cavitary tuberculosis is the hallmark of postprimary tuberculosis. The purpose of this study was to investigate the factors associated with tuberculous pneumonia by making comparison with cavitary tuberculosis.

Methods: The medical records and radiographic findings of patients with cavitary tuberculosis and tuberculous pneumonia, and who were diagnosed between March 2003 and February 2006, were analyzed retrospectively.

Results: Forty patients had cavitary tuberculosis and sixteen patients had tuberculous pneumonia. Fever was more frequent for tuberculous pneumonia, whereas hemoptysis was more frequent for cavitary tuberculosis. The duration of symptoms before visiting the hospital was shorter, but the diagnosis after admission was more delayed for tuberculous pneumonia patients than for cavitary tuberculosis patients. The prevalence of underlying comorbidities such cancer, diabetes, alcoholism and long-term steroid use was not different between the two groups. The patients with tuberculous pneumonia were older and they had lower levels of serum albumin and hemoglobin than those with cavitary tuberculosis. The patients with tuberculous pneumonia showed a tendency to have more frequent endobronchial lesion. Tuberculous pneumonia occurred in any lobe, whereas the majority of cavitary tuberculosis patients had upper lung lesion, but the prevalence of lymphadenopathy, pleural effusion and previous tuberculosis scar was not different between the two groups.

Conclusions: Older age, a lower level of serum albumin and hemoglobin and a random distribution of lesion were associated with tuberculosis pneumonia as compared with cavitary tuberculosis. These findings suggest that the pathogenesis of tuberculous pneumonia might be different from that of cavitary tuberculosis.

Figure 1

Chest X-ray of a 24-year-old woman reveals a cavitary lung lesion at the right upper lung (A). The chest CT scan demonstrates the thick walled cavity at the posterior segment of right upper lung (white arrowed) with a tree in bud pattern (black arrows) (B).

Figure 2

Chest X-ray of an 82-year-old man reveals homogenous consolidation at the right lower lung and the dense nodular lesions in both upper lungs (white arrowed) have not changed during 10 years (A). Chest CT scan demonstrates homogeneous consolidation with an air bronchogram (white arrow) and an old calcified pleural lesion (black arrow) (B).