Prevalence and molecular characterization of Staphylococcus aureus from human stool samples

Abstract

BackgroundTo determine the prevalence of intestinal S. aureus colonization of patients at a large teaching hospital and determine the molecular characteristics of the identified strains. The second objective of this research was to determine risk factors associated with S. aureus intestinal colonization.MethodsA cross-sectional study of 781 specimens from inpatients and outpatients at the University of Iowa Hospitals and Clinics Clinical Microbiology Laboratory was conducted. S. aureus was identified using traditional culture methodologies. Methicillin-resistance was determined via PCR of the mecA gene. PVL PCR, spa typing, and antimicrobial sensitivity testing were also done. A nested case-control study was done on a subset of patients with all colonized patients defined as cases and non-colonized controls. Medical record abstractions were done to identify risk factors for intestinal colonization in the nested study.ResultsOut of 625 patients included in the final study, 58 were positive for S. aureus (9.3%). One isolate was positive for the PVL gene. A high number of isolates were resistant to multiple antibiotics including oxacillin (43.1%), erythromycin (51.7%), and levofloxacin (41.4%). All isolates were susceptible to vancomycin, daptomycin, linezolid, and quinupristin-dalfopristin. In the nested study, having a disease or condition of the gastrointestinal tract significantly increased the odds of intestinal colonization (OR: 1.96, 95% CI: 1.04–3.7; aOR: 13.9, 95% CI: 1.67–115.7). No other variables were significantly associated with increased odds of colonization.ConclusionsS. aureus was identified from the stool of patients at the University of Iowa Hospitals and Clinics, with a large number of those isolates being resistant to antibiotics and may serve a reservoir for subsequent infections as well as asymptomatic transmission.

Species and drug susceptibility profiles of staphylococci isolated from healthy children in Eastern Uganda

“…Staphylococci are a key component of the human microbiota, and around 47 species have been identified [1,2]. They mainly colonize the skin, anterior nares, the nasopharynx, and gut [2][3][4]. Staphylococci are generally nonpathogenic however, when there is breach of the body barriers (e.g.…”

“…Staphylococci are generally nonpathogenic however, when there is breach of the body barriers (e.g. damage to the skin and mucous membranes) or when the immune system is weakened, they become opportunistic pathogens and cause a variety of mild to severe community-and hospital-acquired infections [2][3][4].…”

Identification and molecular characterization of Staphylococcus aureus and multi‐drug resistant MRSA from monkey faeces in China

“…Interestingly, the spa type t13638 was previously reported in S. aureus isolates from cynomolgus macaques in the United States Primate Center (Roberts, Feßler, et al, ; Roberts, Joshi, et al, ), whereas spa type t189 has been found to be associated with human infections in hospitals in China (Song et al, ; Wang et al, ). In addition, the spa type t189 from this study is closely related to hospital‐associated S. aureus t002, which is frequently observed in hospital (Kates et al, ; Li et al, ; Nakao et al, ).…”

Manual emptying of ventilated improved pit latrines and hygiene challenges - a baseline survey in a peri-urban community in KwaZulu-Natal, South Africa

“…were targeted. Both pathogenic strains of E. coli (Galane and Le Roux 2001) and pathogenic staphylococci such as Staphylococcus aureus are found in the gut of humans (Kates et al 2018). E. coli is known to persist on hands for up to 90 min (Ayliffe et al 1988) and on inanimate surfaces for more than ten days (Møretrø et al 2010), thus highlighting the suitability of this microorganism as a hygiene indicator.…”