T his investigati on presents a brief study for monitoring the correlation between the expression of heat-shock protein (HSP) genes; 
dnak, and groES as well as the capsular polysaccharide (caps) gene and antimicrobial susceptibility of extensively drug resistant (XDR)  
Klebsiella pneumoniae in response to a low dose of Gamma (γ) radiation. The XDR K. pneumoniae strains, that were obtained from (UTI) Egyptian patients were identified using the API 20E strip automated system. Their antimicrobial susceptibilities were monitored using standard disc diffusion method in parallel with their minimum inhibition concentrations (MICs) towards standard antibiotics using a micro-titer method, before and after exposure to γ-radiation at a dose of 24.4 Gray (Gy). The expression of  dnak, groES, and cps genes was detected by qRT-PCR under the same conditions. The results demonstrate increasing antibiotic resistance after exposure to γ-radiation. Also, a doubling in the MIC of the tested strains towards CAZ
(ceftazidime) was observed. These results were confirmed by an elevation in the expression of dnak, groES, and cps genes in response to γ-radiation. These preliminary results need more confirmaions, because they assume difficulties in curing immunocompromised patients infected with XDR K. pneumoniae by the currently available antibiotics.