Pulmonary Mycobacterium kansasii Infection in Israel, 1999-2004
Mycobacterium kansasii has traditionally been considered the most virulent of the nontuber-culous mycobacteria.,2 It is the second most common nontuberculous mycobacterium after Mycobacterium avium complex3 and the most common cause of nontuberculous mycobacterial lung disease in the United Kingdom and Western Europe. Infection with M kansasii probably occurs via an aerosol route, Tap water is a major reservoir for M kansasii causing human infection. The incidence of M kansasii infection has a wide geographic variation, being highest in the central and southern United States, and England and Wales. Click Here
Isolation of M kansasii from tap water can be intermittent, which may explain why some investigators have failed to recover it from that source. No other environmental (water or soil) source of M kansasii has been identified. Risk factors include chronic lung disease, previous mycobacterial disease, malignancy, and alcoholism. In immunocompetent patients, pulmonary disease is the most frequent clinical manifestation, although approximately 40% have no associated illness. The prevalence of M kansasii infection may be very high in areas where HIV is common.
According to the American Thoracic Society (ATS) guidelines, the current recommendation for treatment of pulmonary disease caused by M kansa-sii is the regimen of isoniazid, rifampin, and etham-butol administered daily for 18 months with an least 12 months of negative sputum culture results. In patients who are unable to tolerate one of these three drugs, clarithromycin would seem to be a reasonable alternative. M kansasii is also susceptible in vitro to sulfamethoxazole, amikacin, newer quinolones, and rifabutin. The incidence of Mycobacterium tuberculosis in Israel was six to eight cases per 100,000 from 2003 to 2004.
However, because it is not a public health problem and not reportable, there are no data concerning the incidence of M kansasii in Israel. Moreover, little is known about patient demographics, clinical characteristics, association of the disease with HIV, or M kansasii drug sensitivity in nonendemic areas. The aim of the present study was to assess the clinical features, radiologic findings, and drug sensitivity in patients with M kansasii infection in Israel.