Maternal Transmission of Mutans
Streptococci in Severe Early
Childhood Caries.
Noel K. Childers, DDS, MS, PhD
Department of Pediatric Dentistry
The University of Alabama at Birmingham,
Birmingham, AL
Introduction:
Acquisition of MS
• Maternal source:
– High fidelity:
• 71% in Birmingham, AL
• 54% in Sweden
• 51% in Japan
Li, 1995
Emanuelsson, 1998
Kozai, 1999
– Low fidelity:
• 38% in cleft palate patients
• 44% in Chinese population
• 33% in Japanese daycare
children
De Soet, 1998
Li, 2000
Tedjosasongko, 2002
Introduction:
Acquisition of MS
• Non-Maternal Sources:
– 8-31% evidence for paternal transmission
1999 Kozai
1998 Emanuelsson
2002 Tedjosansongko
2004 Ersin
– Evidence for horizontal transfer between
children in daycare
• in Japanese (58%)
• In Brazil (% not reported)
Tedjosansongko 2002
Mattos-Graner 2001
Severe Early Childhood Caries
(S-ECC)
• Clinical strategies to limit maternal MS transmission:
–Recommended by AAPD, AAP, CDC
–Predicated on maternal transmission being the primary means of
MS acquisition in children with S-ECC
• Limited studies on transmission patterns in this population
Pulsed Field Gel Electrophoresis
(PFGE)
• Centers for Disease Control:
– Considered PFGE as the:
“gold standard of bacterial DNA fingerprinting”
– Use PFGE for epidemiological studies of bacterial
infections
• Strengths:
– Highly discriminative
– Reproducible
Methods:
Cohort
• Medically healthy
• Between 18 months and 6 years of age
• Diagnosed with S-ECC (minimum def score of 6)
• Presented for full mouth dental
rehabilitation under general anesthesia
• Biological mother present
Methods:
Plaque Sampling
• Three preoperative:
Cotton Swab
– Mother’s dental plaque (M)
Cotton Swab
– Child’s dental plaque (BP)
– Plaque from child’s carious lesion (BC)
Sterile
Tooth Pick
• Samples placed in reduced transport media
Methods:
Overview
Samples Cultured (MSB agar)
Eight MS isolates per sample
type isolated (Todd Hewitt agar)
Unique genotypes
identified via AP-PCR
DNA from representative
isolates of MS genotypes
were suspended in agarose
plugs and digested with SmaI
Chromosomal Digests
separated via PFGE
Dice coefficients were
generated from gel banding
patterns
(Bionumerics software)
Dice coefficient >70%
indicated match among
PFGE genotypes
Results:
Demographics
• 27 mother/child pairs:
– 4 sibling sets
– 23 unique mothers
• Average Age—41.7 m (Range: 19-82m)
• Gender: 78% male:22% female
• Race: 18% B, 78% W, 4% Arabic
PFGE Dendrograms100% maternal match
Mother/Child pair 18—All isolates share >90% similarity.
Dice (Tol 1.0%-1.0%) (H>0.0% S>0.0%) [0.0%-100.0%]
PFGE
PFGE
2
9
4
9
6
9
8
9
0
0
1
18BP-2
.
18BP-3
.
100
90
90
18M-1
.
18M-2
.
18M-3
.
PFGE Dendrograms-
Partial maternal match
Mother/Child pair 26—Isolate 26BP-2 only 37% similar
to maternal isolates. All other isolates >70% similar.
Dice (Tol 1.0%-1.0%) (H>0.0% S>0.0%) [0.0%-100.0%]
PFGE
0
4
PFGE
0
5
0
6
0
7
0
8
0
9
0
0
1
26BC-1
.
100
88.9
80.6
72
71.1
37.3
37
26BP-1
.
26M-5
.
26M-2
.
26M-1
.
26BP-5
.
26BP-2
.
PFGE DendrogramsNo isolates match mother
Mother/Child pair 28. Maternal isolates are less than
30% similar with isolates found in the child.
Dice (Tol 1.0%-1.0%) (H>0.0% S>0.0%) [0.0%-100.0%]
PFGE
0
PFGE
0
2
0
4
0
6
0
0
1
0
8
96.8
95.3
.
28M-2
28M-3
.
28M-4
.
92.6
96.3
89.7
28M-6
.
28M-7
.
28M-5
.
31.2
31
100
91.1
0
100
0
28BC-3
.
.
28BC-5
.
.
28BC-1
.
.
28BC-4
.
.
28BP-1
.
.
28BP-2
.
.
28M-1
.
.
28M-1
.
.
PFGE Dendrogram Analysis
• 26% (7/27)—All child isolate matches
maternal isolates
• 15% (4/27)—Some child isolates match
maternal isolates/some do not
• 59% (16/27)—No child isolates match
74% (20/27) of patients possessed isolates that did
not match maternal genotypes
PFGE Dendrograms-
Siblings match/no maternal match
• 4/4 siblings sets shared identical
genotypes
• 3/4 siblings sets did not share genotypes
in common with their mother
PFGE Dendrograms-
Siblings match/no maternal match
90
Dice (Tol 1.0%-1.0%) (H>0.0% S>0.0%) [0.0%-100.0%]
PFGE
0
4
0
5
PFGE
0
6
0
7
0
8
0
9
0
0
1
100
88.9
89
76.8
94.7
65
100
100
39.9
40
100
93.8
83.3
100
12BC-1
.
.
12BP-4
.
.
13BP-3
.
.
13BP-4
.
.
13BP-3
.
.
12BC-1
.
.
12BP-4
.
.
13BP-2
.
.
13BP-3
.
.
12M-3
.
.
12M-7
.
.
12M-2
.
.
12M-7
.
.
12M-3
.
.
Discussion:
Evidence for Maternal Transmission
• Observed in 41% of study population
• Evidence was neither:
– Exclusive
– Predominant
• 74% of patients possessed isolates that did not
match maternal genotypes
Low Fidelity of Transmission
• Not sampled at initial acquisition
– Clonal instability
• Not colonized by maternal genotypes
– Genetic/environmental susceptibility to other
colonization mechanism
– S-ECC patients have aberrant, high sucrose
feeding habits
• High sucrose diets:
– favor MS colonization
– May allow indiscriminant colonization
Conclusions:
•
•
•
Maternal transmission is not the
predominant mode of MS transmission
within this S-ECC population.
Siblings with S-ECC may possess similar
MS genotypes, even without receiving the
genotype from their mother.
Practices designed to limit maternal
transmission of MS may have minimal
impact on S-ECC.
Acknowledgments
•
•
•
•
Dr. Stephen Mitchell
Dr. Stephen Moser
Dr. John Ruby
Jennifer Whiddon
Dr. Page Caufield
Dr. Yihong Li
Stephanie Momeni
Mitchell SC, Ruby JD, Moser S, Momeni S, Smith A, Childers NK. 2009.
Maternal Transmission of Mutans Streptococci in Severe-Early Childhood
Caries. Pediatr Dent. Vol. 31: 117-25. (PMID: 19552223 [PubMed indexed for MEDLINE])
Acknowledgments
• NIDCR Grants DE016684, T32 DE07026,
and DE 11147
• Faculty Development Grant from the
Office of the Dean, School of Dentistry,
University of Alabama at Birmingham