pneumoniae isolates
from stool specimens of healthy Chinese and overseas Chinese adults in Asian countries Taiwan China Hong Kong Singapore Malaysia Thailand Japan Vietnam n = 150 n = 128 n = 50 n = 47 n = 64 n = 123 n = 6 n = 24 Serotype K1 11 (7.3) 9 (7) 5 (10) 5 (10.6) 8 (12.5) 0 (0) selleck chemical 1 (16.7) 0 (0) Serotype K2 6 (4) 6 (4.7) 1 (2) 2 (4.3) 1 (1.6) 3 (2.7) 0 (0) 0 (0) Data are presented as no. (%) of isolates Antimicrobial susceptibility testing We randomly and proportionally selected 100 serotypable isolates from different countries for antimicrobial susceptibility testing. The antimicrobial susceptibility pattern was the same in all 97 K. pneumoniae isolates, with uniform resistance to ampicillin and susceptibility to all cephalosporins and aminoglycosides. Serotypes K1/K2 and non-K1/K2 had the same antimicrobial susceptibility pattern (data not shown). Two isolates, including
one serotype Crizotinib molecular weight K1 isolate from Taiwan and one non-K1/K2 serotype from Thailand, were resistant to ampicillin and cefazolin but susceptible to other cephalosporins and aminoglycosides. One serotype K1 isolate from Taiwan was resistant to ampicillin, cefazolin, and amikaicin, but susceptible to other cephalosporins. No extended spectrum β-lactamase isolate was detected during this study. Pulsed-field gel electrophoresis (PFGE) and screening for CC23 representatives by detection of allS by PCR among K1 isolates PFGE and detection of allS gene by PCR among serotype K1 isolates are shown in Figure 1. The original PFGE profiles are
shown in Figure 2 and Figure 3. 31 (79.5%) of the K1 isolates carried allS gene. No major cluster was found among serotype K1 isolates from Asian countries, using previously described criteria [3]. Figure Pregnenolone 1 Dendrogram comparing PFGE profile of K. pneumoniae serotype K1 isolates together with the results of allS detected by PCR. No major clonal cluster of serotype K1 K. pneumoniae isolates was found. TW, Taiwan; CH, China; SP, Singapore; MA, Malaysia; HK, Hong Kong; JP, Japan. Figure 2 PFGE profile of K. pneumoniae serotype K1 isolates from Taiwan and Malaysia. TW, Taiwan; MA, Malaysia. Figure 3 PFGE profile of K. pneumoniae serotype K1 isolates from China, Hong Kong, Singapore and Japan. CH, China; HK, Hong Kong; SP, Singapore; JP, Japan. Discussion The K1 serotype of K. pneumoniae was uncommon among clinical isolates before the 1990s [14].