Evaluation of Antimicrobial Peptide LL-37 Role in the Treatment of Antibiotic-Resistant Bacteria in haematological patients

Abstract

Haematological diseases are disorders in the structure and content of the blood. Multi-drug resistant (MDR) bacteria increase rates of morbidity and mortality; therefore, our study focuses on detection of resistant bacteria and role of peptide LL-37 in their treatment. One hundred different clinical specimens were cultured and isolated, and the identification was done by using the Vitek2 system. The minimum inhibitory concentrations (MICs) of peptide LL-37 were calculated by using the microdilution technique. the results showed that, females were more than males, and the most haematological diseases were Acute Myeloid Leukemia (AML) at 20%, followed by Acute Lymphoblastic Leukemia (ALL) and non-Hodgkin Lymphoma (NHL) at 18%. Most specimens were sputum and blood, followed by wound swabs, and then others. Antibiotic susceptibility testing showed all investigated bacteria to Benzylpenicillin, Ampicillin, and Ticarcillin were resistance 100%, In contrast, all isolates investigated to Linezolid, Tigecycline, Ertapenem, and Minocycline were sensitive 100%. Most the investigated isolates for Colistin antibiotic were intermediate (89.47%) and variable susceptible for the other antibiotics.  All investigated MDR isolates were sensitive to the antimicrobial peptide LL-37 at concentrations ranging from 31.25 to 125 µg/ml. in conclusion it is necessary to develop this antimicrobial peptide for particularly in haematological disease patients.