Subclinical miliary Mycobacterium bovis following BCG immunotherapy for transitional cell carcinoma of the bladder

Abstract

The authors present an unusual case of a 51-year-old man who developed relatively mild non-specific symptoms following intravesical BCG instillation for superficial transitional cell carcinoma of the bladder, with radiological investigations demonstrating typical features of miliary tuberculosis (TB). Transbronchial biopsy showed small foci of poorly formed granuloma suggestive of Mycobacterium infection. The patient's respiratory symptoms only became apparent 7 days after discharge having had 4 weeks of unremarkable inpatient stay where he remained clinically well. Prompt anti-TB treatment resulted in a remarkable improvement in his symptoms and radiological appearance, supporting the diagnosis of disseminated Mycobacterium bovis infection. This case highlights the importance of recognising miliary M bovis as a potential complication in patients receiving BCG immunotherapy, and that the disease course can be subclinical with delayed onset of symptoms.

Figure 1

The patient's initial chest radiograph on admission to the hospital: showing bilaterally diffuse increased shadowing consistent with mild pulmonary oedema.

Figure 2

Chest CT scans performed within the first week of admission demonstrating bilateral miliary nodules of random distribution with bilateral hilar, subcarinal, paratracheal and prevascular lymphadenopathy.

Figure 3

Chest CT scans performed within the first week of admission demonstrating bilateral miliary nodules of random distribution with bilateral hilar, subcarinal, paratracheal and prevascular lymphadenopathy.

Figure 4

Chest CT scans performed within the first week of admission demonstrating bilateral miliary nodules of random distribution with bilateral hilar, subcarinal, paratracheal and prevascular lymphadenopathy.

Figure 5

Histological images of transbronchial biopsy showing a lung parenchyma with mild interstitial fibrosis and chronic inflammation, with an area of small foci that has features suggestive of poorly formed granulomata (areas highlighted by red arrows).

Figure 6

Histological images of transbronchial biopsy showing a lung parenchyma with mild interstitial fibrosis and chronic inflammation, with an area of small foci that has features suggestive of poorly formed granulomata (areas highlighted by red arrows).

Figures 7

Axial images from repeat chest CT scans performed 10 days after initiation of antituberculosis medications: showing considerable improvement in appearance with disappearance of many of the tiny intrapulmonary nodules with resolution of thickened interlobular septa.

Figure 8

Axial images from repeat chest CT scans performed 10 days after initiation of antituberculosis medications: showing considerable improvement in appearance with disappearance of many of the tiny intrapulmonary nodules with resolution of thickened interlobular septa.

Figure 9

Axial images from repeat chest CT scans performed 10 days after initiation of antituberculosis medications: showing considerable improvement in appearance with disappearance of many of the tiny intrapulmonary nodules with resolution of thickened interlobular septa.

Figure 10

Axial images of repeat chest CT scans performed 10 weeks after initiation of antituberculosis medications: showing further improvement with resolution of many of the smaller intrapulmonary nodules.

Figure 11

Axial images of repeat chest CT scans performed 10 weeks after initiation of antituberculosis medications: showing further improvement with resolution of many of the smaller intrapulmonary nodules.

Figure 12

Axial images of repeat chest CT scans performed 10 weeks after initiation of antituberculosis medications: showing further improvement with resolution of many of the smaller intrapulmonary nodules.

Figure 13

Axial images of repeat chest CT scans performed 10 weeks after initiation of antituberculosis medications: showing further improvement with resolution of many of the smaller intrapulmonary nodules.