Investigation on epidemiology of pan-drug resistant Pseudomonas aeruginosa in Guangzhou / 中华检验医学杂志

ABSTRACT

Objective To analyze a potential outbreak mechanism 0f Pseudomonas eruginosa by investigating the homology of pan-drug resistance isolates(PDR)isolated in four hospitals of Guangzhou from March 2005 to March 2007.Methods The pulse-field gel lectrophoresis(PFGE)was used to detectl34 strains of pan-drug resistant Pseudomonas eruginosa in four hospitals,and determined whether they were derived from the same clone.Results 1 34 strains were classified into 56 types based on PFGE pattern. Type A Was the commonest clone among four hospitals,45 strains belonged to type A,mainly spreaded in hospital A. The rest strains were identified7 for type B,6 for type C,6 for type D,which were isolated from hospital B to hospital D,respectively.There were 40 strains classified for individual types.General comparison showed there Was no a large clone existing in all four hospitals,though type Q clone appeared in hospital B and hospital D.One strain from hospital B and one strain from hospital C had 80%homology with type A from hospital A.The environment survey showed there was no clonal strain of type A found in hospital A,although various samples from respiratory therapy equipment,bronchoscopes and medical erosols were collected and cultivated for three times during the period.However,six patients arrying type A Pseudomonas aeruginosa had been admitted to the same ICU of hospital A for many times.Analysis of antimicrobial resistance of the common clone from four hospitals revealed that 42 of 43 type A of Pseudomonas aernginosa produced IMP-9 metallo β-lactamase.The strains of type B,type C and type D didn't produced metallo B. 1actamase.Conclusions The various degree of clonal spread of pan-drug resistance Pseudomonas aeruginosa had occurred in four hospitals individually in two years.There Was also clonal spread among some hospitals. It is important to monitor the patients colonized with epidemic clones to prevent clonal spread.