Table 2

Bacterial findings in breast milk of women with and without symptoms of mastitis: Odds Ratios with 95% confidence intervals for symptoms of mastitis


Healthy donors (n = 466)
Women with mastitis (n = 192)

Bacterial Species
Occurrence of bacteria in breast milk n (%)
Mean (SD) counts (cfu/L)
Occurrence of bacteria in breast milk n (%)
Mean (SD) counts (cfu/L)
Odds Ratio for occurrence of mastitis symptoms (95%CI)

CNS
419 (90%)
106(± 1.1)
160 (83%)
106(± 1.1)
0.60 (0.35, 0.91)
p = 0.02
Viridans Streptococci
233 (50%)
105(± 1.0)
113 (59%)
105(± 1.0)
1.43 (1.02, 2.01)
p = 0.04
Staphylococcus aureus
145 (31%)
106(± 1.2)
87 (45%)
106(± 1.3)
1.81 (1.29, 2.60)
p = 0.001
Group B streptococci
47 (10%)
106(± 1.5)
41 (21%)
106(± 1.4)
2.40 (1.50, 3.71)
p = <0.001
Entercoccus faecalis
28 (6%)
106(± 1.1)
16 (8%)
106(± 1.1)
0.70 (0.36, 1.43)
p = 0.36
Group G streptococci
6 (1%)
106
3 (2%)
107

Group A streptococci
3 (1%)
107
2 (1%)
107

Pneumococci
4 (1%)
107
5 (3%)
105

Corynebacteria
2 (0.4%)
104
1 (0.5%)
105

Enterobacteriaceae
36 (8%)
106
2 (1%)
106

Acinetobacter species
12 (3%)
106
0
0

Pseudomonas species
24 (5%)
107
1 (0.5%)
106

Bacillus species
5 (1%)
105
1 (0.5%)
104

Propionibacterium species
3 (1%)
106
2 (1%)
106

Candida species
4 (1%)
105
4 (2%)
105


CNS = coagulase negative staphylococci, SD = Standard Deviation

Kvist et al. International Breastfeeding Journal 2008 3:6   doi:10.1186/1746-4358-3-6