Insight to Acintobacter baumannii

BACKGROUND AND OBJECTIVESAcinetobacter baumannii is the most important member associated with hospital-acquired infections worldwide. This aerobic Gram-negative coccobacillus had been regarded as a low-grade pathogen, but it is a successful pathogen responsible for opportunistic infections of the skin, bloodstream, urinary tract, and other soft tissues. Several virulence factors have been identified by genomic and phenotypic analyses, including outer membrane porins, phospholipases, proteases, lipopolysaccharides (LPS), capsular polysaccharides, protein secretion systems, and iron-chelating systems. A. baumannii has a number of resistance mechanisms, including β-lactamases, aminoglycoside-modifying enzymes, efflux pumps, permeability defects, and modifications of target sites.MATERIALS AND METHODSThe accumulation of several resistance mechanisms in A. baumannii has gradually decreased the number of antibiotic classes available to treat A. baumannii infections in clinical practice. A. baumannii Intrinsically resistant to a number of commonly used antibiotics, such as aminopenicillins, first- and second-generation cephalosporins. For susceptible organisms, first-line therapy consists of a carbapenem, such as imipenem-cilastatin, meropenem, or doripenem. carbapenem resistance rates for A. baumannii have been rising dramatically worldwide.RESULTS AND DISCUSSIONColistin-based combination therapies have been preferred over colistin monotherapy given colistin’s suboptimal pharmacokinetics and pharmacodynamics. Tigecycline, developed for the treatment of multidrug-resistant (MDR) pathogens and having potent in vitro activity against A. Baumannii.CONCLUSIONPhage therapy has gained particular importance for the treatment of bacterial infections. Single Phage Therapy:Therapies based on a single virus type, also known as monophage therapies, have been extensively applied as A. baumannii treatments. Phage-Encoded Enzymes for the Treatment of A. Baumannii: Endolysins are phage-produced hydrolases that lyse bacterial cell walls, allowing the further release of progeny phages at the end of the replication cycle . Depolymerases are phage-derived enzymes that facilitates the early stages of phage infection by degrading extracellular bacterial protein . Phage–antibiotic synergy (PAS) refers to the usage of antibiotics at sublethal doses in combination with phage administration, with the aim of increasing the release of phage-progeny from bacterial cells . Cocktail Therapy: Phage cocktails typically consist of multiple phages combined, with each of them having unique host specificity due to selective affinity towards a specific bacterial receptor, conferring a broad therapeutic lysis spectrum.

کلیدواژه ها:

Acintobacter baumannii ، phage therapy ، Antibiotic resistance