Possible beta-lactamase activities detectable in infective clinical specimens

Area of Science:

• Microbiology
• Pharmacology
• Clinical Chemistry

Background:

• Beta-lactam antibiotics are crucial in treating bacterial infections.
• Antibiotic resistance, including enzymatic inactivation, is a growing public health concern.
• Detection of antibiotic-inactivating enzymes in clinical samples is important for understanding treatment efficacy.

Purpose of the Study:

• To investigate the presence and nature of biological beta-lactam antibiotic-inactivating activities in clinical specimens.
• To identify specific bacterial species associated with these inactivating activities.
• To determine the spectrum of antibiotic inactivation by different bacterial isolates.

Main Methods:

• Collection and sterilization of clinical specimens (bacteriuria and suppurating pleural fluids) using membrane filtration.
• Quantification of ampicillin and cephalothin inactivation by filtrates from 1 ml of each specimen.
• Identification of bacterial species present in the filtrates, including Klebsiella sp., Enterobacter sp., and Pseudomonas aeruginosa.

Main Results:

• Biological beta-lactam antibiotic-inactivating activities were detected in both bacteriuria and suppurating pleural fluids.
• Filtrates yielding Klebsiella sp. generally showed inactivation activity against ampicillin.
• Filtrates yielding Enterobacter sp. and Pseudomonas aeruginosa demonstrated inactivation activity against cephalothin.

Conclusions:

• Clinical specimens can harbor biological activities capable of inactivating beta-lactam antibiotics.
• Specific bacterial genera are associated with the inactivation of particular beta-lactam antibiotics.
• These findings highlight the potential for in-situ antibiotic inactivation in infections caused by these bacteria.