Downloaded from http://adc.bmj.com/ on July 1, 2015 - Published by group.bmj.com
PostScript
LETTER
Group B streptococci in milk and neonatal colonisation We much appreciated the study by Filleron and coworkers.1 The authors analysed the literature concerning cases of group B streptococcus (GBS) late-onset disease (LOD) associated with infected milk. The presence of GBS in milk is a controversial issue and differences in definitions or methods used in some studies can lead to conflicting results. For example, some studies cited in this review provide no information concerning milk collection or milk culture methods. Most studies do not measure the bacterial inoculum, an aspect that could be crucial. Therefore, it is possible that in some cases reported in the literature, the milk was ‘contaminated’ with GBS during sampling rather than previously ‘infected’. Filleron et al1 concluded that breast milk may account for repeated GBS transmission to neonates, and may favour gut translocation and subsequent LOD. The authors recommend a more systematic bacteriological analysis to search for GBS excretion, particularly in asymptomatic mothers. However, they underline the lack of prospective, longitudinal studies able to clarify the dynamics of GBS in breast milk and neonatal gut colonisation. We recently cultured 160 mother–baby pairs (≥35 weeks gestation, 50% exposed to intrapartum antibiotics) from delivery to 2 months postpartum.2 Eighty-three mothers were found to carry GBS (rectovaginal site) at least once in the study period. Among 35 colonised neonates, 32 were born to GBS carrier mothers and 17 out of 32 neonates were colonised both in the throat and rectum (heavily colonised).
Arch Dis Child April 2014 Vol 99 No 4
Six of 83 GBS carrier mothers had a positive milk culture in the absence of mastitis and their respective neonates were heavily colonised. Interestingly, the milk culture was found positive simultaneously with neonatal colonisation (five cases) or a few hours after neonatal colonisation (one case). No cases of culture-positive milk were found among non-carrier mothers. We identified three neonates (born to 83 carrier mothers) with GBS infection. Breast milk culture was positive in two out of three infected neonates, but there was no evidence that milk was the source of neonatal infection. Indeed, signs of infection presented some hours before the positive milk culture (one case) or 20 days later, when milk had already become sterile (one case). We concluded that GBS in milk is closely associated with heavy neonatal colonisation. This may explain the high rates of positive milk cultures found after LOD presentation,3 as it is likely that an infant with LOD is also heavily colonised. High rates of positive milk cultures from mothers of newborns with recurrent LOD might only reflect persistent neonatal GBS colonisation at mucous sites, as evidenced by cases where discontinuation of breast feeding does not prevent recurrence.4 Unlike in the case of breastfed full-term neonates, a positive milk culture might have greater importance if a preterm infant with LOD is fed pump-extracted milk containing GBS. In this case, contamination of the pump extraction device may be suspected as the source of GBS. GBS transmission must be further investigated before breast feeding is considered as the cause of LOD in all cases of positive milk culture. Alberto Berardi,1 Cecilia Rossi,1 Isotta Guidotti,1 Andrea Zucchini,2 Luigi De Carlo,3
Fabrizio Ferrari,1 on behalf of the GBS Prevention Working Group, Emilia-Romagna 1
Terapia Intensiva Neonatale, Azienda OspedalieroUniversitaria Policlinico, Modena, Italy Unità Operativa di Pediatria, Ospedale Civile, Faenza, Italy 3 Unità Operativa di Pediatria, Ospedale del Delta, Ferrara, Italy 2
Correspondence to Dr Alberto Berardi, Unità Operativa di Terapia Intensiva Neonatale, Azienda Ospedaliero- Universitaria Policlinico, Via del Pozzo 71, Modena (MO) 41121, Italy; [email protected] Contributors AB, CR and IG drafted the manuscript; AZ and LDC participated in its design, coordination and acquisition of data and helped to draft the manuscript and FF has been involved in revising the manuscript critically for intellectual content. Competing interests None. Patient consent Obtained. Ethics approval Regional Ethical Committee. Provenance and peer review Not commissioned; externally peer reviewed. To cite Berardi A, Rossi C, Guidotti I, et al. Arch Dis Child 2014;99:395. Accepted 2 November 2013 Published Online First 28 November 2013 Arch Dis Child 2014;99:395. doi:10.1136/archdischild-2013-305291
REFERENCES 1
2
3
4
Filleron A, Lombard F, Jacquot A, et al. Group B streptococci in milk and late neonatal infections: an analysis of cases in the literature. Arch Dis Child Fetal Neonatal Ed 2013 Aug 16. [Epub ahead of print]. Berardi A, Rossi C, Creti R, et al. Group B streptococcal colonization in 160 mother-baby pairs: a prospective cohort study. J Pediatr. 2013;163:1099–104.e1 Berardi A, Rossi C, Lugli L, et al. Group B Streptococcus late-onset disease: 2003–2010. Pediatrics 2013;131:e361–8. Soukka H, Rantakokko-Jalava K, Vähäkuopus S, et al. Three distinct episodes of GBS septicemia in a healthy newborn during the first month of life. Eur J Pediatr 2010;169:1275–7.
395
Downloaded from http://adc.bmj.com/ on July 1, 2015 - Published by group.bmj.com
Group B streptococci in milk and neonatal colonisation Alberto Berardi, Cecilia Rossi, Isotta Guidotti, Andrea Zucchini, Luigi De Carlo, Fabrizio Ferrari and on behalf of the GBS Prevention Working Group, Emilia-Romagna Arch Dis Child 2014 99: 395 originally published online November 28, 2013
doi: 10.1136/archdischild-2013-305291 Updated information and services can be found at: http://adc.bmj.com/content/99/4/395
These include:
References Email alerting service
This article cites 3 articles, 1 of which you can access for free at: http://adc.bmj.com/content/99/4/395#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
PostScript
LETTER
Group B streptococci in milk and neonatal colonisation We much appreciated the study by Filleron and coworkers.1 The authors analysed the literature concerning cases of group B streptococcus (GBS) late-onset disease (LOD) associated with infected milk. The presence of GBS in milk is a controversial issue and differences in definitions or methods used in some studies can lead to conflicting results. For example, some studies cited in this review provide no information concerning milk collection or milk culture methods. Most studies do not measure the bacterial inoculum, an aspect that could be crucial. Therefore, it is possible that in some cases reported in the literature, the milk was ‘contaminated’ with GBS during sampling rather than previously ‘infected’. Filleron et al1 concluded that breast milk may account for repeated GBS transmission to neonates, and may favour gut translocation and subsequent LOD. The authors recommend a more systematic bacteriological analysis to search for GBS excretion, particularly in asymptomatic mothers. However, they underline the lack of prospective, longitudinal studies able to clarify the dynamics of GBS in breast milk and neonatal gut colonisation. We recently cultured 160 mother–baby pairs (≥35 weeks gestation, 50% exposed to intrapartum antibiotics) from delivery to 2 months postpartum.2 Eighty-three mothers were found to carry GBS (rectovaginal site) at least once in the study period. Among 35 colonised neonates, 32 were born to GBS carrier mothers and 17 out of 32 neonates were colonised both in the throat and rectum (heavily colonised).
Arch Dis Child April 2014 Vol 99 No 4
Six of 83 GBS carrier mothers had a positive milk culture in the absence of mastitis and their respective neonates were heavily colonised. Interestingly, the milk culture was found positive simultaneously with neonatal colonisation (five cases) or a few hours after neonatal colonisation (one case). No cases of culture-positive milk were found among non-carrier mothers. We identified three neonates (born to 83 carrier mothers) with GBS infection. Breast milk culture was positive in two out of three infected neonates, but there was no evidence that milk was the source of neonatal infection. Indeed, signs of infection presented some hours before the positive milk culture (one case) or 20 days later, when milk had already become sterile (one case). We concluded that GBS in milk is closely associated with heavy neonatal colonisation. This may explain the high rates of positive milk cultures found after LOD presentation,3 as it is likely that an infant with LOD is also heavily colonised. High rates of positive milk cultures from mothers of newborns with recurrent LOD might only reflect persistent neonatal GBS colonisation at mucous sites, as evidenced by cases where discontinuation of breast feeding does not prevent recurrence.4 Unlike in the case of breastfed full-term neonates, a positive milk culture might have greater importance if a preterm infant with LOD is fed pump-extracted milk containing GBS. In this case, contamination of the pump extraction device may be suspected as the source of GBS. GBS transmission must be further investigated before breast feeding is considered as the cause of LOD in all cases of positive milk culture. Alberto Berardi,1 Cecilia Rossi,1 Isotta Guidotti,1 Andrea Zucchini,2 Luigi De Carlo,3
Fabrizio Ferrari,1 on behalf of the GBS Prevention Working Group, Emilia-Romagna 1
Terapia Intensiva Neonatale, Azienda OspedalieroUniversitaria Policlinico, Modena, Italy Unità Operativa di Pediatria, Ospedale Civile, Faenza, Italy 3 Unità Operativa di Pediatria, Ospedale del Delta, Ferrara, Italy 2
Correspondence to Dr Alberto Berardi, Unità Operativa di Terapia Intensiva Neonatale, Azienda Ospedaliero- Universitaria Policlinico, Via del Pozzo 71, Modena (MO) 41121, Italy; [email protected] Contributors AB, CR and IG drafted the manuscript; AZ and LDC participated in its design, coordination and acquisition of data and helped to draft the manuscript and FF has been involved in revising the manuscript critically for intellectual content. Competing interests None. Patient consent Obtained. Ethics approval Regional Ethical Committee. Provenance and peer review Not commissioned; externally peer reviewed. To cite Berardi A, Rossi C, Guidotti I, et al. Arch Dis Child 2014;99:395. Accepted 2 November 2013 Published Online First 28 November 2013 Arch Dis Child 2014;99:395. doi:10.1136/archdischild-2013-305291
REFERENCES 1
2
3
4
Filleron A, Lombard F, Jacquot A, et al. Group B streptococci in milk and late neonatal infections: an analysis of cases in the literature. Arch Dis Child Fetal Neonatal Ed 2013 Aug 16. [Epub ahead of print]. Berardi A, Rossi C, Creti R, et al. Group B streptococcal colonization in 160 mother-baby pairs: a prospective cohort study. J Pediatr. 2013;163:1099–104.e1 Berardi A, Rossi C, Lugli L, et al. Group B Streptococcus late-onset disease: 2003–2010. Pediatrics 2013;131:e361–8. Soukka H, Rantakokko-Jalava K, Vähäkuopus S, et al. Three distinct episodes of GBS septicemia in a healthy newborn during the first month of life. Eur J Pediatr 2010;169:1275–7.
395
Downloaded from http://adc.bmj.com/ on July 1, 2015 - Published by group.bmj.com
Group B streptococci in milk and neonatal colonisation Alberto Berardi, Cecilia Rossi, Isotta Guidotti, Andrea Zucchini, Luigi De Carlo, Fabrizio Ferrari and on behalf of the GBS Prevention Working Group, Emilia-Romagna Arch Dis Child 2014 99: 395 originally published online November 28, 2013
doi: 10.1136/archdischild-2013-305291 Updated information and services can be found at: http://adc.bmj.com/content/99/4/395
These include:
References Email alerting service
This article cites 3 articles, 1 of which you can access for free at: http://adc.bmj.com/content/99/4/395#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
