Staphylococcus spp. Resistente a meticilina y Enterococcus spp. Resistente a Vancomicina aislados de pacientes del servicio de Medicina y emergencia de un hospital al norte del Perú

Objective: Determine the frequency of methicillin-resistant Staphylococcus spp. and vancomycin-resistant Enterococcus spp. in asymptomatic patients attending the Medicine and Emergency Service at Lambayeque Regional Hospital in Peru. Methods: A total 101 patients attending the Medicine and Emergency Service at Lambayeque Regional Hospital were studied from April to August 2017. The nasal, pharyngeal and rectal regions were considered for sample taking. Primary isolation was performed on mannitol salt agar and bile aesculin agar plates supplemented with 6 μg/ml oxacillin and 6 μg/ml vancomycin, respectively. Identification was carried out by classic biochemistry. Antimicrobial susceptibility tests were based on the Kirby-Bauer and minimum inhibitory concentration methods. Results: A carrier frequency of 83.17% was determined. 94.07% of the Staphylococcus isolates were mecA+ methicillin-resistant in 75%, and 43.33% displayed high-level resistance (>128 μg/ml) to this antimicrobial. Glycopeptide-resistant isolates were not found. Enterococcus exhibited a resistance frequency of 54.29% to vancomycin and 42.84% to teicoplanin. Van A was the prevailing phenotype (37.14%). High-level resistance was also determined in this genus (>128 μg/ml) in 27.50% of the isolates. Conclusion: A high frequency was observed of carriers of the genera Staphylococcus and Enterococcus. Antimicrobial-multiresistant strains are present in asymptomatic carriers.