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Prevention of group B streptococcal neonatal disease. A plea for a European consensus

2001; Elsevier BV; Volume: 7; Issue: 1 Linguagem: Inglês

10.1046/j.1469-0691.2001.00196.x

1469-0691

Manuel de la Rosa Fraile, L. Cabero, Antònia Andreu, Gopal Rao,

Pneumonia and Respiratory Infections

Group B streptococcal (GBS) early onset infection (EOGBS) is the leading cause of life-threatening bacterial neonatal infection during the first week of life in the developed world, with an incidence of 1–3per 1000 live births in USA when there is no preventive intervention [1Edwards MS Baker CJ Streptococcus agalactiae (Group B streptococcus).in: Mandell GL Bennett JE Dolin R Principles and practice of infectious diseases. 5th edn. Churchill Livingstone, New York2000: 2156-2167Google Scholar]. The fatality rate ranges from 5 to 10% at present, but those who survive may have permanent neurological sequelae such as cognitive dysfunction, deafness or visual impairment [1Edwards MS Baker CJ Streptococcus agalactiae (Group B streptococcus).in: Mandell GL Bennett JE Dolin R Principles and practice of infectious diseases. 5th edn. Churchill Livingstone, New York2000: 2156-2167Google Scholar, 2Schuchat A Neonatal group B streptococcal disease: screening and prevention.N Engl J Med. 2000; 343: 209-210Crossref PubMed Scopus (48) Google Scholar]. In Europe the incidence (per 1000 live births) of EOGBS without preventive measures varies between the 0.2–0.3 of early reports from Denmark [3Mayon White RT The incidence of GBS disease in neonates in different countries.Antibiot Chemother. 1985; 35: 17-27PubMed Google Scholar] and the more recent data of 0.76 in Finland [4Kalliola S Vuopio-Varkila J Takala AK Eskola J Neonatal group B streptococcal disease in Finland: a ten-year nationwide study.Pediatr Infect Dis J. 1999; 18: 806-810Crossref PubMed Scopus (87) Google Scholar], 4.5 in Rennes (France) [5Poulain P Betremieux P Donnio PY Proudhom JF Karege G Giraud JR Selective intrapartum anti-bioprophylaxys of group B streptococci infection of neonates: a prospective study in 2454 subsequent deliveries.Eur J Obstet Gynecol Reprod Med. 1997; 72: 137-140Abstract Full Text PDF PubMed Scopus (20) Google Scholar], 5.4 in Vienna (Austria) [6Hafner E Sterniste W Rosen A et al.Group B streptococci during pregnancy: a comparison of two screening and treatment protocols.Am J Obstet Gynecol. 1998; 179: 677-681Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar], 1.42 in Sunderland (UK) [7Bignardi GE Surveillance of neonatal group B streptococcal infection in Sunderland.Commun Dis Public Health. 1999; 2: 64-65PubMed Google Scholar], 1.15 in Luton (UK) [8Beardsall K Thompson MH Mulla RJ Neonatal group B streptococcal infection in South Bedfordshire, 1993–98.Arch Dis Child Fetal Neonatal Ed. 2000; 82: F205-F207Crossref PubMed Google Scholar], 0.4 in Oxford (UK) [9Moses LM Heath PT Wilkinson AR Jeffery HE Isaacs D Early onset group B streptococcal neonatal infection in Oxford, 1985–96.Arch Dis Child Fetal Neonat Ed. 1998; 79: F148-F149Crossref PubMed Scopus (51) Google Scholar], 0.54 in Norway [10Aavitsland P Hoiby EA Lystad A Systemic group B streptococcal disease in neonates and young infants in Norway, 1985–94.Acta Paediatr. 1996; 85: 104-105Crossref PubMed Scopus (29) Google Scholar], 0.4–9 in Andalusia (Spain) [11Baca M Sanchez MJ Perea-Milla E et al.Perinatal group B streptococcal infections in Andalusia (Spain) (abstract).Pren Neonat Med. 2000; 5: 70Google Scholar] and 2.06 in Barcelona (Spain) (Andreu et al, personal communication, August 2000). GBS is usually a commensal bacterium that asymptomatically colonizes the vaginal or rectal areas of 10–30% of pregnant women [1Edwards MS Baker CJ Streptococcus agalactiae (Group B streptococcus).in: Mandell GL Bennett JE Dolin R Principles and practice of infectious diseases. 5th edn. Churchill Livingstone, New York2000: 2156-2167Google Scholar]. In these women, GBS can cause preterm labor, chorioamnionitis, postpartum endometritis, postpartum wound infection and sepsis [12Krohn MA Hillier SL Baker CJ Maternal peripartum complications associated with vaginal Group B streptococci colonization.J Infect Dis. 1999; 179: 1410-1415Crossref PubMed Scopus (78) Google Scholar, 13Bosh J Pericot A Amoros M Ros R Endometritis puerperal: estudio de 52 casos con diagnostico microbiológico y clínico.Enferm Infecc Microbiol Clin. 1995; 13: 203-208PubMed Google Scholar]. Invasive GBS infections also cause significant morbidity and mortality in non-pregnant adults, mainly in otherwise compromised patients [1Edwards MS Baker CJ Streptococcus agalactiae (Group B streptococcus).in: Mandell GL Bennett JE Dolin R Principles and practice of infectious diseases. 5th edn. Churchill Livingstone, New York2000: 2156-2167Google Scholar, 14Gimenez M Sopena N Viñado B et al.Infecciones invasivas por Streptococcus agalactiae en un hospital general universitario durante un periodo de 10 años.Enferm Infecc Microbiol Clin. 1996; 14: 300-303PubMed Google Scholar, 15Muñoz P Llancaqueo A Rodriguez-Creixems M Pelaez P Martin L Bouza E Group B streptococcus bacteremia in nonpregnant adults.Arch Int Med. 1997; 157: 213-216Crossref PubMed Google Scholar]. The most important predictive circumstance that leads to EOGBS is the exposure of the newborn to the organism in the birth canal. There are also some well-deined maternal risk factors that favor the development of infection in an exposed infant [16Ancona RJ Ferrieri P Williams PP Maternal factors that enhance the acquisition of group B streptococci by newborn infants.J Med Microhiol. 1980; 13: 273-280Crossref PubMed Scopus (75) Google Scholar, 17American College of Obstetricians and Gynecologists Prevention of early-onset group B streptococcal disease in newborns.ACOG Comm Opin. 1996; 173: 1-8Google Scholar, 18American Academy of Pediatrics Committee on Infectious Diseases and Committee on Fetus and Newborn Revised guidelines for prevention of early-onset group B streptococcal (GBS) infections.Pediatrics. 1997; 99: 489-496Crossref PubMed Scopus (305) Google Scholar]. These factors include premature birth, maternal chorioamnionitis, prolonged membrane rupture (> 18 h), intrapartum fever, a previous sibling with EOGBS and GBS bacteriuria. Another factor for developing the disease is exposure to a high maternal inoculum of a virulent GBS strain. A further critical issue for a newborn to develop the disease is a low concentration in the mother's serum of antibodies to the capsular polysaccharide of the colonizing GBS strain [19Baker CJ Kasper DL Correlation of maternal antibody deficiency with susceptibility to neonatal group B streptococcal infection.N Engl J Med. 1976; 294: 753-756Crossref PubMed Scopus (482) Google Scholar]. Conjugate vaccines might be an excellent tool against GBS infections in mothers, infants, and even in nonpregnant adults, but they are still under investigation [20Baker CJ Paoletti LC Wessels MR et al.Safety and immuno-genicity of capsular polysaccharide-tetanus toxoid conjugate vaccines for group B streptococcal types Ia and lb.J Infect Dis. 1999; 179: 142-150Crossref PubMed Scopus (145) Google Scholar] and are not yet commercially available. Since 1979 [21Yow MD Mason EO Leeds LJ Thompson PK Clark DJ Gardner SE Ampicillin prevents intrapartum transmission of group B streptococcus.JAMA. 1979; 241: 1245-1247Crossref PubMed Scopus (178) Google Scholar], it has been known that intrapartum treatment of colonized mothers with ampicillin or penicillin reduces GBS colonization of newborns and that most cases of EOGBS can be prevented by treating colonized pregnant women with intravenous antibiotics during labor [22Boyer KM Gotoff SP Prevention of early-onset neonatal group B streptococcal disease with selective intrapartum chemoprophylaxis.N Engl J Med. 1986; 314: 1665-1669Crossref PubMed Scopus (542) Google Scholar, 23Garland SM Fliegner JR Group B streptococcus (GBS) and neonatal infections: the case for intrapartum chemoprophylaxis.Aust NZ J Obstet Gynaecol. 1991; 31: 119-122Crossref PubMed Scopus (113) Google Scholar]. In the USA, the Center for Disease Control and Prevention (CDC) issued guidelines for prevention of EOGBS in 1996 [24Centers for Disease Control and Prevention Prevention of group B streptococcal disease: A public health perspective.Morbid Mortal Wkly Rep. 1996; 45: 1-24PubMed Google Scholar], which were endorsed by the American College of Obstetricians and Gynecologists and the American Academy of Pediatrics [17American College of Obstetricians and Gynecologists Prevention of early-onset group B streptococcal disease in newborns.ACOG Comm Opin. 1996; 173: 1-8Google Scholar, 18American Academy of Pediatrics Committee on Infectious Diseases and Committee on Fetus and Newborn Revised guidelines for prevention of early-onset group B streptococcal (GBS) infections.Pediatrics. 1997; 99: 489-496Crossref PubMed Scopus (305) Google Scholar]. These guidelines recommend the use of either a screening-based or a risk-based approach to identify candidates for intrapartum antibiotic prophylaxis. The risk-based approach provided intrapartum antibiotics to women who had any of the above-mentioned risk factors. The screening-based approach proposes routine prenatal GBS screening between 35 and 37 weeks' gestation, and intrapartum antibiotics are recommended for all women who are either colonized, or who presented in labor before 37 weeks' of gestation, or whose colonization status is unknown and who present risk factors. To optimize the yielding of GBS cultures the CDC recommends using selective broth media and testing vaginal and rectal specimens. The main drawback of the CDC risk-factor approach is that several studies indicate that more than 50% of cases of EOGBS appear in the absence of any known risk factor [25Andreu A Barranco M Bosch J et al.Prevention of perinatal Group B streptococcal disease in Europe.Scand J Infect Dis. 1997; 29: 532Crossref PubMed Scopus (6) Google Scholar, 26Juncosa T Bosch J Dopico E et al.Infección neonatal por Streptococcus agalactiae. Estudio multicéntrico en el área de Barcelona.España Enferm Infecc Microbiol Clin. 1998; 16: 312-315PubMed Google Scholar, 27Towers CV Suriano K Asrat T The capture rate of at risk term newborns for early onset group B streptococcal sepsis determined by a risk factor approach.Am J Obstet Gynecol. 1999; 181: 1243-91997Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar]. Since the publication of the CDC guidelines a significant number of US hospitals have adopted prevention policies [2Schuchat A Neonatal group B streptococcal disease: screening and prevention.N Engl J Med. 2000; 343: 209-210Crossref PubMed Scopus (48) Google Scholar, 28Centers for Disease Control and Prevention Adoption of hospital policies for prevention of perinatal group B streptococcal disease - United States.Morhid Mortal Wkly Rep. 1998; 47: 667-670Google Scholar, 29Centers for Disease Control and Prevention Adoption of perinatal group B streptococcal disease prevention recommendations by prenatal-care providers – Connecticut and Minnesota, 1998.Morbid Mortal Wkly Rep. 2000; 49: 228-232PubMed Google Scholar, 30Factor SH Whitney CG Zywicki SS Schuchat A Effects of hospital policies based on 1996 group B streptococcal disease consensus guidelines. The active bacterial core surveillance team.Obstet Gynecol. 2000; 95: 377-382Crossref PubMed Scopus (41) Google Scholar] and there are data that suggest that the incidence of EOGBS has now dropped below 0.6/1000 live births [31Schrag SJ Zywicki S Parley MM et al.Group B streptococcal disease in the era of intrapartum antibiotic prophylaxis.N Engl J Med. 2000; 342: 15-20Crossref PubMed Scopus (798) Google Scholar]. In some US institutions the rate has fallen from 1.16 to 0.14/1000 live births [32Brozanski BS Jones JG Krohn MA Sweet RL Effect of a screening-based prevention policy on prevalence of early onset group B streptococcal sepsis.Obstet Gynecol. 2000; 95: 496-501Crossref PubMed Scopus (58) Google Scholar] or from 1.7 to 0.3/1000 [33Truong W Yancey MK Lentz SL Reduction of early-onset group B streptococcal sepsis with universal screening and intrapartum antimicrobial therapy for preterm and colonized term parturients.Obstet Gynecol. 2000; 95: S8Crossref Google Scholar]. and now the CDC has recommended that "GBS prevention activities be integrated into all obstetric care programs" (Available at http://www.cdc.gov/ncidod/emergplan/11obj13.htm – retrieved on 21 August 2000). In other developed countries, an important drop in EOGBS has also taken place when a prevention policy has been set up, e.g. in Australia the incidence fell from 2 per 1000 live births in 1991–93 to 0.5 in 1995–97 [34Isaacs D Royle JA Intrapartum antibiotics and early onset neonatal sepsis caused by group B streptococcus and by other organisms in Australia. Australasian study group for neonatal infections.Pediatr Infect Dis J. 1999; 18: 524-528Crossref PubMed Scopus (131) Google Scholar]. It has been suggested [2Schuchat A Neonatal group B streptococcal disease: screening and prevention.N Engl J Med. 2000; 343: 209-210Crossref PubMed Scopus (48) Google Scholar, 35McDuffie Jr, RS McGregor JA Gibbs RS Adverse perinatal outcome and resistant Enterobacteriaceae after antibiotic usage for premature rupture of the membranes and group B streptococcus carriage.Obstet Gynecol. 1993; 82: 487-489PubMed Google Scholar] that prevention protocols greatly increase the proportion of women who get antibiotics during labor and delivery, and this could increase the risk of neonatal sepsis caused by resistant Enterobacteriaceae. Though some alarming reports on this issue have been published [36Mercer BM Carr TL Beazley DD Crouse DT Sibai BM Antibiotic use in pregnancy and drug-resistant infant sepsis.Am J Obstet Gynecol. 1999; 181: 816-821Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar, 37Levine EM Ghai V Barton JJ Strom CM Intrapartum antibiotic prophylaxis increases the incidence of gram-negative neonatal sepsis.Infect Dis Obstet Gynecol. 1999; 7: 210-213Crossref PubMed Google Scholar], neonatal sepsis caused by Gram-negative bacteria is more often a disease of prematurity, and the increase in Gram-negative neonatal disease seems related to situations in which the use of the CDC risk-based approach leads to a prolonged use of ampicillin. Moreover, in other studies the decline in the incidence of EOGBS after installing a screening-based prevention program has not been accompanied by an increase in Gram-negative sepsis [33Truong W Yancey MK Lentz SL Reduction of early-onset group B streptococcal sepsis with universal screening and intrapartum antimicrobial therapy for preterm and colonized term parturients.Obstet Gynecol. 2000; 95: S8Crossref Google Scholar, 38Isaacs D Prevention of early onset group B streptococcal infection: screen treat or observe?.Arch Dis Child Fetal Neonatal Ed. 1998; 79: P81-P82Crossref Scopus (25) Google Scholar, 39Main EK Slagle T Prevention of early onset invasive neonatal Group B streptococcal disease in a private hospital setting. The superiority of culture-based protocols.Am J Obstet Gynecol. 2000; 182: 1344-1354Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar, 40Landry L, Richardson S, Matlow A, et al. Incidence of neonatal sepsis due to gram-negative bacteria in Toronto, Canada, 1996–1999. In: Abstracts of the 40th Interscience Conference on Antimicrobial Agents and Chemotherapy. 2000: 446.Google Scholar]. However, the severity of resistant Escherichia coli neonatal sepsis suggests caution regarding the widespread use of ampicillin instead of penicillin for EOGBS prophylaxis [41Katz PF Hibbard JU Ranganathan D Meadows W Ismail M Group B streptococcus: to culture or not to culture?.J Perinatol. 1999; 19: 337-342Crossref PubMed Scopus (10) Google Scholar]. In 1998 in Spain the Societies of Obstetrics and Gynaecology and of Neonatology (with the endorsement of the Societies of Infectious Diseases and Clinical Microbiology and of Chemotherapy) issued the Spanish Consensus Guidelines to Prevent EOGBS [42Sociedad Española de Obstetricia y Ginecología Recomendaciones para la prevención de la infección perinatal por estreptococo grupo B.Prog Obstet Gynecol. 1998; 41: 431-435Google Scholar]. These guidelines follow in general the CDC screening-based approach using either Granada Medium [43Rosa-Praile M Rodriguez-Granger J Cueto-Lopez M et al.Use of Granada medium to detect group B streptococcal colonization in pregnant women.J Clin Microhiol. 1999; 37: 2674-2677PubMed Google Scholar] or the broth-enrichment technique to detect GBS-carriers at weeks 35–37 and also include recommendations on the management of newborns to GBS-carrier mothers when prophylaxis has not been used or has been incomplete. Since then a substantial number of Spanish hospitals have adopted this policy, and a considerable drop in the incidence of EOGBS has also been observed [11Baca M Sanchez MJ Perea-Milla E et al.Perinatal group B streptococcal infections in Andalusia (Spain) (abstract).Pren Neonat Med. 2000; 5: 70Google Scholar, 44Mazon A Salvo MS Ezcurra R Resultados del programa de prevención de la infección neonatal por estreptococo del grupo B.Prog Obstet Gynecol. 2000; 43: 233-236Google Scholar]. Thus in Catalonia the incidence dropped from 1.92/1000 live births in 1994 to 0.57/1000 in 1998 (Andreu et al, personal communication, August 2000). In other European countries in which a prevention policy has been set up a similar reduction has been noticed. In Vienna the incidence of EOGBS [6Hafner E Sterniste W Rosen A et al.Group B streptococci during pregnancy: a comparison of two screening and treatment protocols.Am J Obstet Gynecol. 1998; 179: 677-681Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar] dropped from 5.4/1000 (1992–94) to 1.1/1000 (1995–97) and in Rennes from 4.5/1000 in 1993 to 1.6/1000 in 1995 [5Poulain P Betremieux P Donnio PY Proudhom JF Karege G Giraud JR Selective intrapartum anti-bioprophylaxys of group B streptococci infection of neonates: a prospective study in 2454 subsequent deliveries.Eur J Obstet Gynecol Reprod Med. 1997; 72: 137-140Abstract Full Text PDF PubMed Scopus (20) Google Scholar] after prevention programs were instituted. Now, more than 40 years after the dramatic emergence of GBS as a major cause of threatening infections in the newborn [45Eickhoff TC Klein JO Daly A Ingall D Finland M Neonatal sepsis and other infections due to group B β-hemolytic streptococci.N Engl J Med. 1964; 271: 1221-1228Crossref PubMed Scopus (314) Google Scholar], and more than 20 years after the rationale of antibiotic prophylaxis was established it is clear that EOGBS disease is a very important cause of suffering for parents and newborns, and is largely preventable with currently available methods. Though it has been suggested that "when the incidence of early onset streptococcal infection is low expensive preventive measures may not be justified" [34Isaacs D Royle JA Intrapartum antibiotics and early onset neonatal sepsis caused by group B streptococcus and by other organisms in Australia. Australasian study group for neonatal infections.Pediatr Infect Dis J. 1999; 18: 524-528Crossref PubMed Scopus (131) Google Scholar], the layperson is seriously concerned about GBS, and GBS support associations have been founded in Europe (UK Group B Strep Support, available at http://www.gbss.org.uk/, retrieved on 22 August 2000; Dutch Foundation GBS, available at http://home.wxs.nl/~sgbs/gbs.html, retrieved on 22 August 2000) and in USA (USA Group B Strep Association, available at http://www.GroupBStrep.org/, retrieved on 22 August 2000). Quoting an American colleague [46Deutchman M Thoughts on the prevention of neonatal group B streptococcal infection.Am Fam Physician. 1998; 57 (2605–07.): 2602PubMed Google Scholar], we can affirm, "First and foremost, we must not ignore the problem. Neonatal Group B streptococcal infection is more prevalent than many other conditions we screen for in pregnancy, and the effect can be just as devastating". So perhaps the time has arrived for European obstetricians, neonatologists, infectious diseases physicians and clinical microbiologists to catch up with their American colleagues and together look deeper into the issue of prevention of GBS neonatal infection. A common European consensus on prevention policies should now be established.