[A study on clinical features of Mycobacterium kansasii pulmonary disease in women]

To clarify clinical features of M. kansasii pulmonary disease in women.

We performed a retrospective analysis of M. kansasii pulmonary disease in women compairing with that in men. We focused on 8 female cases of M. kansasii pulmonary disease during the past 7 years from June 1998 to August 2005.

The cases of M. kansasii pulmonary disease in women have increased in the latter few years. The mean age of female cases was higher than that of male cases, 65.6 and 53.1 years old, respectively. The number of female cases with smoking history was lower than that of male cases, 37.5% and 90.0%, respectively. Two female cases had underlying pulmonary diseases, as compared with 10 male cases, 25.0% and 33.3%, respectively. The radiological findings in female cases included 2 cavitary opacities, 1 infiltrative opacity and 5 nodular, bronchiectatic opacities, as compared with 27 cavitary opacities, 1 infiltrative opacity, 1 solitary nodular opacity and 1 nodular, bronchiectatic opacity in male cases. MAC was also detected in 2 female cases, who presented with nodular, bronchiectatic opacities. On the other hand, there were 6 female cases, in which no other NTM was detected. 3 cases showed cavitary or infiltrative opacities, which improved with the following 3 tuberculous drugs INH, RFP, and EB (HRE), while others showed nodular, bronchiectatic opacities, in which 2 cases showed radiological exacerbations without any treatment and another one revealed an improvement with HRE.

M. kansasii pulmonary disease in women tends to be identified in elderly who smoke less and have no underlying pulmonary diseases, and most of radiological findings in female cases revealed nodular, bronchiectatic opacities. Summing up all these findings, clinical features of M. kansasii pulmonary disease in women was considered to resemble that of MAC infection, and it was speculated that the increase of M. kansasii pulmonary disease in women has some relationship with that of MAC infection in middle or lingular lobe. However, it was confirmed that some cases of M. kansasii pulmonary disease in women might primarily present with nodular, bronchiectatic lesions, regardless of MAC infection.