The usefulness of single-enzyme amplified-fragment length polymorphism (AFLP) analysis for the subtyping of Mycobacterium kansasii type I isolates was evaluated. This simplified technique classified 253 type I strains into 12 distinct clusters. The discriminating power of this technique was high, and the technique easily distinguished between the epidemiologically unrelated control strains and our clinical isolates. Overall, the technique was relatively rapid and technically simple, yet it gave reproducible and discriminatory results. This technique provides a powerful typing tool which may be helpful in solving many questions concerning the reservoirs, pathogenicities, and modes of transmission of these isolates.Mycobacterium kansasii is the most common cause of pulmonary nontuberculous mycobacterial infection in the nonhuman immunodeficiency virus-infected population in many parts of the world (4,6,9,12,16,19,25). Of all nontuberculous mycobacterial diseases, the clinical course of M. kansasii lung disease most closely parallels that caused by M. tuberculosis infection (12,36). Although it has seldom been recovered from soil (10, 22), M. kansasii has frequently been isolated from tap water and is thought to be acquired from the environment rather than by case-to-case transmission (8,17,18,20,24,29,31,37).The first typing method developed for M. kansasii was phage typing. Other features, especially catalase activity, have been used to type M. kansasii isolates. Isolates with high catalase activities were considered more virulent (23). Analysis of the 16S rRNA sequence (27), amplification of the 16S-23S rRNA spacer region (1), PCR-restriction fragment length polymorphism (RFLP) analysis of the hsp65 gene (7, 33), and detection of insertion sequence element IS1652 (38) showed that M. kansasii contains a subspecies genetically distinct from the typical M. kansasii isolates.M. kansasii has been classified into five subspecies or types (types I to V) on the basis of PCR-RFLP analysis of the hsp65 gene (7, 33). These results have been confirmed by differences in the sequences of the 16S-23S rRNA spacer region (2) and by RFLP analysis with the major polymorphic tandem repeat probe (23). Recently, two new types (types VI and VII) have been described (26,32). Of the seven types identified, M. kansasii type I is the most prevalent type from human sources worldwide. Moreover, large restriction fragment-pulsed-field gel electrophoresis (LRF-PFGE) (2, 14, 23), amplified-fragment length polymorphism (AFLP) analysis (23), and randomly amplified polymorphic DNA analysis (2) have produced polymorphic patterns within each type.By use of these typing methods, minimal genetic polymorphism was noted among type I strains. These results gave the impression that type I shows substantial clonality (21). This apparent clonality may have resulted from the insufficient discriminatory powers of the techniques used. Solutions to questions about the reservoirs, pathogenicities, and modes of transmission of these isolates require more discrim...

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Changesin the electrophoretic distribution of plasma proteins were noted in wild animals with a variety of parasitic and infectious diseases.This technique may be useful in screening for disease before death or sacrifice of animals.

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