carbapenemase

B- lactam antibiotics is one of the most important antibiotic used worldwide for bacterial infectiouse diseases. By producing beta-lactamase enzymes in bacteria the central ring in beta-lactam antibiotics is hydrolyzed, and antibiotic inactivate and develop resistance.

In this article, it is discussed.a brief review of various methods of inactivation of beta-lactam antibiotics by bacteria.

This review article has been written by studying the articles that have been published in scientific journals regarding the inactivation mechanisms of various beta-lactam antibiotics. 

Beta-lactam antibiotics, by binding to the penicillin-binding protein present in the bacterial cell membrane, inhibit transpeptidases and break down the peptidoglycan, resulting in the destruction of the cell wall and the death of the bacteria. Beta-lactamase enzymes hydrolyze and inactivate beta-lactam antibiotics before they reach the penicillin-binding protein in the cytoplasmic membrane. So far, more than 140 different types of beta-lactamase have been identified, which are classified based on different criteria and effective on different classes of beta-lactam antibiotics.

Carbapenem is the last defensive line against gram negative bacterial infections that are resistant to extended spectrum antibiotics. Hence، using a proper method for determining the production of carbapenemase enzyme which controls the infection factors resistant to carbapenem antibiotic seemed to be essential. The aim of this study was qualitative analysis of Hodge test for finding a suitable method in determining carbapenemase. Thirty six samples of Klebsiella pneumoniae with multiple antibiotic resistances capable of producing carbapenemase enzyme were collected from medical centers and laboratories، and approved through CHROMagar method. All the samples were analyzed with regards to the form of sensitive zone as clover shape in Hodge test، according to CLSI instruction. All collected samples were identified for carbapenemase producing with CHROMagar KPC method. Thirty samples were reported positive with Hodge test، respectively. The sensitivity of Hodge test was calculated to be 83. 3%. Also، all the negative control isolations were accompanied by negative result and its sensitivity was reported to be 100%. On the other hand، it was observed that all the positive cases were resistant to antibiotics including Ampicillin، Amikacin، Gentamicin، Tetracycline، Ceftazidime، Ciprofloxacin and Imipenem. Discussion and According to the obtained results from Hodge test on the collected samples، using this method was determined to be appropriate in primary diagnosis and under the conditions where preparation of specific culture media or using molecular methods was not possible.