Once again confirmed the possibility of infection of the newborn MRSA with breast milk
The suggestion that breast milk could be a source of infection for newborns with methicillin-resistant strains of Staphylococcus aureus (MRSA) was confirmed again.
Scientists at the University of Chicago who investigated the epidemic of infections in newborns in the intensive care unit (ICU) caused by strains of Staphylococcus aureus (MRSA ) resistant to methicillin (MRSA), indicate that premature infants can become infected with MRSA through breast milk even if the mother shows no clinical signs of MRSA infection.
Triplet, born at 26 weeks gestation by caesarean section, was systematically screened for MRSA. Initially, in two children (hereinafter referred to as child A and child B), MRSA was not detected in the study of nasopharyngeal smears and umbilical wound smears. However, MRSA was isolated from studies repeated on days 10 and 18 of life. In the third child, MRSA was not detected during screening or in other studies. Bacteriological examination of breast milk, which the children received with a nasogastric tube, revealed an increase in MRSA.
Child A developed sepsis and MRSA was released in a multiple blood culture study from the 14th day of life. Child B developed conjunctivitis and MRSA was isolated in a 70-day study of conjunctival discharge.
MRSA strains isolated from children had a similar antibiotic resistance profile and pulsed gel electrophoresis confirmed the genetic identity of the strains.
Data from other studies indicate the possibility of infection of newborns with MRSA through breast milk. In 1987, a case of meningitis and conjunctivitis was described in a child whose growth rate of MRSA, coagulase-negative staphylococcus and Acinetobacter calcoaceticus was detected during a bacteriological examination. cerebrospinal fluid; in conjunctival fluid studies, MRSA has been isolated. Although MRSA was also isolated during a bacteriological examination of breast milk, no molecular genetic studies have been performed 1.
An epidemic of MRSA infections in infants associated with the use of expressed breast milk is described by Cooke RP et al., However, isolated strains of MRSA have also not been studied in molecular genetics 2.
Novak F.R. and the co-authors reported that in a study of 500 breast milk samples in 1999, an increase in MRSA 3 was detected in 11% of the cases.
Chicago researchers were unable to establish the degree of relationship between maternal colonization of MRSA and breast milk infection: for ethical reasons, they did not collect material for further studies.
The researchers propose to identify the following risk factors for maternal colonization of MRSA: cesarean section, use of antibiotics during the perinatal period and multiple pregnancies. Another risk factor not yet proven for the acquisition of MRSA may be medical manipulations during in vitro fertilization.
In addition, it can be assumed that breast milk can become infected during storage in the ICU. However, if this assumption is correct, the development of an infection would be observed in other children.
By analyzing the available data on the problem, the researchers came to the conclusion that during the epidemic of MRSA infection in intensive care for newborns, excluding other risk factors, breast milk can be considered a source of colonization and infection with MRSA. If a bacteriological examination of breast milk reveals an increase in MRSA, it is necessary to establish the source of contamination, including screening for the mother, and to carefully examine the methods of storing and using breast milk.