Abstract

STUDY EFFECT OF HUMAN SERUM PROTEIN ON BIOFILM FORM BY STAPHYLOCOCCUS.EPIDERMIDIS

Dr. Nihad Khalawe*, Dr. Rajwa H. Essa, Dr. Suzan S. Hussain
, Dr. Leeqa H. Mahde

Abstract

Background: Staphylococcus.epidermidis is one of coagulase negative staphylococci (CONS) are now well established as major nosocomial pathogens associated with infections of indwelling medical devices. In recent years many studies focused on S. epidermidis because of its ability of to adhere to the surfaces and form biofilm, which are the most important virulence factor in S. epidermidis and essential step in the pathogenesits of this bacteria therefore this study aimed to Isolated bacteria from different source (blood, catheter urine, wound and burn swabs as well as skin and nasal swabs from hospital staff) and identificated by using varies methods (culturing, Api system, Vitek 2 System as well as Bact for bacteria which isolated from blood). Study of biofilm forming by S. epidermidis by microtiter plates. determine concentration of protein in sera of patients, extraction of biofilm and used as antigens against sera of patients’ infected by S. epidermidis, and study the effect biofilm of this bacteria. Results: A total of 50 isolate of staph.epidermidis isolated from different sources include blood, catheter urine specimen, wound and burn swabs and swabs of skin and nasal hospital staff, which was carried out in ( AL-Kindy, Imam Ali, Al- Wasete, Baghdad, Ibn Al-Balade) Hospitals and teaching laboratories of Medical City Hospitals in Baghdad from February -2014 to September -2014. S. epidermidis isolates, which gained from blood, urine catheters, wound and burn swab as well as from swab of skin and nasal hospital staff by (60)% of the isolates produced biofilm while (40)% respectively no biofilm phenotypically. Sera from patients with S. epidermidis infections showed reactivity with S. epidermidis antigens (whole cells) as: six of S. epidermidis antigens agglutinated in titer 1:2, 1: 4, 1: 32 and 1:128 of patients sera (antibodies) while 5,9 , 11 of S. epidermidis antigens agglutinated in the patients sera in titer (1:16, 1:64, 1:256) respectively, also concentration of sera protein (5.032) μg/ml gave 90% inhibition but concentration of sera protein (1.394) μg/ ml gave 30% inhibition. Conclusion: Sera from patients with S. epidermidis infections can reactivity with S. epidermidis antigens (whole cells), also concentration of sera protein (5.032) μg/ ml gave 90% inhibition but concentration of sera protein (1.394) μg/ ml gave 30% inhibition.

Keywords: S. epidermidis Coagulase Negative Staphylococci: CONS, antibodies, antigens.