Microbiological spectrum and susceptibility pattern of clinical isolates from the neonatal unit in a single medical center.
BACKGROUND
Infections are a frequent and significant cause of morbidity and mortality in neonatal units. The bacterial pathogens and their susceptibility patterns should be monitored in hospital settings. The aim of the study was to describe the distribution of the bacterial agents and their antibiotic resistant and susceptibility patterns in the Special Neonatal Care Unit (SNCU).


METHODS
A retrospective analysis of results of microbiologically tested samples (blood, cerebrospinal fluid, urine, stool, eye excretions, external ear swabs, nasopharyngeal swabs and skin swabs) taken from newborns hospitalized in one SNCU in Warsaw (Poland) was conducted. The period analyzed was from July 1st, 2010 to December 31st, 2010.


RESULTS
A total of 838 cultured samples were collected in the period analyzed. Three hundred seventy three of them (44.5%) were positive. The majority of the cultured microorganisms were classified as colonization: 338/373 (91%) strains. Gram negative bacteria were predominant colonizing flora: 227/338 (67%) strains. Gram positive bacteria were predominant causative agents in newborns with infections: 26/35 (74%) strains. 57.9% of Escherichia coli isolates were resistant to amoxicillin and ampicillin. 100% of Klebsiella pneumoniae were resistant to amikacin and netilmicin. Staphylococcus aureus methicillin resistant strains were cultured in 2.7% of cases.


CONCLUSIONS
Gram negative species continue to be predominant agents of neonatal colonizing flora while gram positive bacteria remain important causative agents for symptomatic infections. Continuous monitoring of bacterial flora and its antibiotic susceptibility pattern is necessary to provide a successful antibiotic policy. Current results may be used for future national and international comparison.
Department of Family Medicine, Warsaw Medical University, Poland.
Aneta
A
Nitsch-Osuch
Department of Basic Sciences, Wroclaw Medical University, Poland.
Irena
I
Choroszy-Król
Department of Pediatric Infectious Diseases, Wroclaw Medical University, Poland.
Ernest
E
Kuchar
Department of Epidemiology and Tropical Medicine, Military Institute of Medicine, Warszawa, Poland.
Krzysztof
K
Korzeniewski
Department of Family Medicine, Warsaw Medical University, Poland.
Katarzyna
K
Życińska
Department of Family Medicine, Warsaw Medical University, Poland.
Kazimierz
K
Wardyn
D000583:Amikacin / Q000627:therapeutic use; D000658:Amoxicillin / Q000627:therapeutic use; D000667:Ampicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001826:Body Fluids / Q000382:microbiology; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D004756:Enterobacteriaceae Infections / Q000188:drug therapy / Q000382:microbiology; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D009428:Netilmicin / Q000627:therapeutic use; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D009428:Netilmicin; D000667:Ampicillin; D000658:Amoxicillin; D000583:Amikacin