Increased risk of infection in newborns
Despite the growing progress made in medicine, infections in neonatology still are of special significance. Newborns are exposed to a particularly high risk of infection because of the immaturity of their immune system and some of their organs, such as the skin, the lungs and the gastrointestinal tract.
Infections belong to the essential causes of morbidity and mortality in the newborn
In the period from January 2005 to December 2009, the National Reference Center for the Surveillance of Nosocomial Infections (NRZ) with the Hospital Infection Surveillance System (KISS) registered for the risk sector “Neonatological Intensive Medical Care” a total of 24,301 newborns (birth weight: < 1,500 g) with 901,037 days on ICU, 4,486 sepsis cases and 596 pneumonias. The further evaluation revealed that antibiotics were administered on ICU on a total of 270,671 days (30 %).
The risk of infection increased with sinking gestation age and birth weight. Catheter-associated infections constituted an additional risk in intensive-medical care.
Nosocomial infections prolong hospitalization periods and increase treatment costs in the hospital. The prophylaxis of infections and the introduction of new prevention measures are therefore absolutely necessary and for economic reasons as well.
Infectious germs originate from the mother and the immediate environment of the child
The first intestinal colonization of the infant's intestines with commensal or pathogenic bacteria depends, among other factors, on the vaginal and gut microbiota of the infant's mother as well as the microbiota on the surface of her skin. Bacteria in the environment during and after delivery also have an impact on the first intestinal colonization.
A study compared the microbial intestinal colonization of sixty newborns in three hospitals. The evaluation revealed a typical frequency distribution of the respectively prevailing bacterial species for each hospital. Opportunistic or obligate pathogens (e. g. Klebsiella pneumoniae ssp. ozaenae, Shigella ssp., Yersinia enterocolitica, etc.) were detected in the stool samples of several children. A certain extent of these species still prevailed until the children had been discharged from hospital.
30 % of the E. coli strains isolated from the stool samples during the first week of life exhibited pathogenic features, e. g. ability to induce hemolysis. Candida albicans was determined in seven newborns in one hospital. Hospital-specific differences were also revealed when the meconium (first stool of a newborn) was analyzed. In two hospitals, 50 % of the children's melena stools have already been colonized with microbes. In the third hospital, even 95 % of all melena stools were contaminated. 3
Type and diversity of the microbial composition are decisively influenced by the environment. Particularly in premature infants, developmentally disordered or diseased newborns, the risk of colonization with potentially pathogenic bacteria and antibiotic-resistant hospital-acquired microorganisms increases strongly in the course of hospitalization. The increasing number of antibiotic resistances among pathogenic bacteria is alarming (e. g. VRE, EBL, MSRA).
Frequently perinatal-acquired infective agents
pathogenic E. coli, Streptococci (Group B), Enterococci, Staphylococci, Haemophilus influenzae, Listeria ssp., Herpes simplex virus
Common pathogens of postnatal infections
Gram-positive bacteria: Staphylococcus haemolyticus, Staphylococcus epidermis, Pneumococci
Gram-negative bacteria: Pathogenic E. coli, Klebsiella ssp., Pseudomonas aeruginosa, Enterobacter, Shigella ssp., Salmonella ssp., Serratia ssp., Proteus spp.
Yeasts: Candida albicans
Avoiding colonization with unwanted bacteria
Various measures are applicable in order to restrict the colonization of the newborn's intestines with pathogenic or potentially pathogenic bacteria:
Hygiene measures minimize the transmission of pathogens (e. g. antiseptic measures, hand disinfection, disinfection of medical devices).
"Sparing", targeted application of antibiotics avoids the further spread of antibiotic-resistant microorganisms.
The postnatal colonization with E. coli strain Nissle 1917 (Mutaflor Suspension) acts antagonistically against pathogenic bacteria and thus protects against dysbiosis of the intestinal microbiota right from the beginning. Furthermore, EcN enhances the immune competence by an early stimulation of the development of the gut-associated immune system in the newborn.