Multiple nodular opacities only involving the right middle pulmonary lobe: Unusual manifestation of tuberculosis.

Bronchoscopy should be actively performed to differentiate pulmonary tuberculosis in patients with lesions in the middle lobe, which are unaccompanied by bronchiectasis or present without obvious lesions in other lobes.

CASE PRESENTATION

Although the pulmonary middle lung lobe is a frequent site for Mycobacterium avium complex infection, bronchoscopy should be actively performed to differentiate pulmonary tuberculosis in patients with lesions in the middle lobe, which are unaccompanied by bronchiectasis or present without obvious lesions in other lobes.

A 79‐year‐old man with a history of renal cancer surgery presented with an abnormal shadow on chest radiography, which was performed during a routine checkup. He had no subjective symptoms. Chest computed tomography revealed multiple nodular opacities in the right middle pulmonary lobe (Figure 1). Smears and cultures of sputum for acid‐fast bacilli were negative. Bronchoscopy did not reveal any endobronchial lesions, and Mycobacterium tuberculosis (TB) was isolated from the bronchoalveolar lavage fluid, obtained from the right middle bronchus. The shadow in the middle lobe disappeared by anti‐TB chemotherapy.

FIGURE 1

Computed tomography revealing multiple nodular opacities in the right middle pulmonary lobe (A‐C). Bronchiectasis is absent, and pulmonary lesions are not seen in other lobes. Arrowhead showing the minor fissure separating right upper and middle lobe

DISCUSSION AND CONCLUSION

The pulmonary middle lung lobe is a frequent site for Mycobacterium avium complex (MAC) infection. Middle lobe TB is usually associated with endobronchial TB, which presents as right middle lobe syndrome, and reports of localized pulmonary TB involving the middle lobe only are rare. Bronchiectasis is less common in patients with TB, and the occurrence of small nodules in only a single lobe is more common in patients with TB than that in patients with MAC infection. Our case suggests that bronchoscopy should be actively performed to differentiate between TB and MAC in patients with lesions in the middle lobe, which are unaccompanied by bronchiectasis or present without obvious lesions in other lobes.

CONFLICT OF INTEREST

None.

AUTHOR CONTRIBUTIONS

AO: was responsible for conception, design, drafting, image modification, and finalizing; YT: was responsible for drafting; YM: was responsible for design and image modification; KF: was responsible for conception and finalizing; KS: was responsible for design and finalizing; all authors read and approved the final manuscript.

ETHICAL APPROVAL

Informed consent for publication and related images has been obtained from the patient.