Molecular epidemiology of Staphylococcus aureus nasal colonization among patients and their parents /guardian in an Iranian referral hospital.
BACKGROUND
Carriage of Staphylococcus aureus in the nose appears to play a key role in the epidemiology and pathogenesis of infection. It is important to investigate the genetic relatedness of S. aureus and MRSA clones in different geographic regions. The aim of this study was to assess the nasal carriage rate of S. aureus, including MRSA strains in both hospitalized children and general adult population (parents/guardian). In addition, antibiotic susceptibility pattern and molecular diversity of S. aureus in both population was evaluated in an Iranian referral pediatrics Hospital.


METHODS
All samples were obtained through nasal screening of patients and general adult population at admission and discharge day. The prevalence, resistance, and molecular diversity of all S. aureus isolates were examined.


RESULTS
In the current study, nasal carriage of S. aureus and Staphylococcus non aureus was identified in 384 (26%) and 1004 (68%) of the study population. The prevalence of MRSA nasal carriage in children and adults was 6.6% (29 out of 438) and 2.8% (29 out of 1046), respectively. Among S. aureus strains isolated obtained from patients and general adult population at admission day, high sensitivity to most of the antibiotics such as vancomycin (100%), rifampin (95%), linezolid (94%), quinupristin/dalfopristin (94%), minocycline (94%), chloramphenicol (89%), gentamycin (87%), amikacin (87%), clindamycin (86%) and moxifloxacin (83%) was seen. The most resistance antibiotics were penicillin (96-98%) and methicillin (44-47%). The susceptibility patterns of nasal S. aureus strains isolated at discharge day was not statistically different from S. aureus isolates obtained at admission day. Admission S. aureus isolated strains of 77 patients (64%) were similar to the isolated S. aureus strains of discharge, while S. aureus isolated strains of 43 patients (36%) was not similar to the strain of discharge (had similarity of less than 70%).


CONCLUSIONS
High prevalence of nasal carriage of S. aureus and MRSA indicates the urgent need to improve strategies for management of S. aureus infections. Our findings are useful for understanding of S. aureus nasal colonization dynamics within the patients and general population. Surveillance for S. aureus in community settings can provide data on circulating strains and might help developing control measures for reducing of infection spread in hospitals.
Pediatric Infectious Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran.
Babak
B
Pourakbari
Department of Infectious Diseases, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
Mahmoud
M
Khodabandeh
Pediatric Infectious Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran.
Shima
S
Mahmoudi
Department of Infectious Diseases, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
Farah
F
Sabouni
Radiology Department, Rasool-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran.
Alireza
A
Aziz-Ahari
Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran.
Abbas
A
Bahador
School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Sepideh
S
Keshavarz Valian
Pediatric Infectious Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran.
Reihaneh
R
Hosseinpour Sadeghi
Pediatric Infectious Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Infectious Diseases, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: smamishi@sina.tums.ac.ir.
Setareh
S
Mamishi
D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D014644:Genetic Variation; D060005:Genotyping Techniques; D006801:Humans; D007223:Infant; D007492:Iran / Q000453:epidemiology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000472:pathogenicity; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D009666:Nose / Q000382:microbiology*; D010290:Parents; D015995:Prevalence; D012017:Referral and Consultation; D013203:Staphylococcal Infections / Q000453:epidemiology*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D055815:Young Adult
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial
Antibiotic susceptibility patterns; Genotyping; Staphylococcus aureus