Serotype distribution and incidence of invasive early onset and late onset group B streptococcal disease amongst infants in Singapore

Table 1 Clinical presentation and risk factors of infants with invasive GBS Infection in KKH, Singapore (2010–2018)

Patient characteristics	LOD^a (n = 55)	EOD^a (n = 16)	Univariate analysis			Multivariate analysis^b
Patient characteristics	LOD^a (n = 55)	EOD^a (n = 16)	Odds ratio	95% CI	p value	Odds ratio	95% CI	p value
Day of life when GBS infection occurred, median (IQR)	34 (17–64)	1 (1–3)	NA			NA
Type of disease			NA			NA
Bacteremia only	40 (72.7)	14 (87.5)
Meningitis only	2 (3.6)	0
Bacteremia and meningitis	12 (21.8)	1 (6.3)
Bacteremia, endophthalmitis and arthritis	0	1 (6.3)
Arthritis	1 (1.8)	0
Mode of delivery^c			0.2	0.05–1.1	0.058	–		0.138
Normal or assisted vaginal delivery	33 (60.0)	14 (87.5)
Caesarean section	20 (36.4)	2 (12.5)
Race			15.6	3.2–76.6	< 0.001	27.1	3.0–243.1	0.003
Chinese	38 (69.1)	2 (12.5)
Non-Chinese	17 (30.9)	14 (87.5)
Gender			1.0	0.3–3.1	0.961	NA
Male	34 (61.8)	10 (62.5)
Female	21 (38.2)	6 (37.5)
Gestational age			0.4	0.1–1.2	0.081	–		0.480
Preterm^d	12 (21.8)	7 (43.8)						0.480
Term	43 (78.2)	9 (56.3)
Birth weight			2.7	0.8–9.2	0.104	–		0.555
Normal birth weight	45 (81.8)	10 (62.5)
Low birth weight	10 (18.2)	6 (37.5)
Maternal GBS status			10.0	2.0–33.3	0.007	20.0	0.004–0.5	0.012
Negative or unknown	51 (92.7)	10 (62.5)
Infection or colonization	4 (7.3)	6 (37.5)
Adequate intrapartum antibiotics			3.5	1.0–12.4	0.042	–		0.637
Yes or not required	47 (85.5)	10 (62.5)
No	8 (14.5)	6 (37.5)
Prolonged rupture of membrane^e			NA^f	NA^f	0.267	NA
Yes	4 (7.3)	0 (0)
No	51 (92.7)	16 (100)
Peripartum maternal pyrexia			0.2	0.03–1.1	0.072	–		0.759
Yes	2 (3.6)	3 (18.8)
No	53 (96.4)	13 (81.3)
Serotypes^g			5.3	1.5–19.3	0.007	–		0.099
III	36 (65.5)	6 (37.5)
Others	9 (16.4)	8 (50.0)

KKH KK Women’s and Children’s Hospital, LOD late onset disease, EOD early onset disease, IQR interquartile range, GBS group B streptococcus, NA not applicable
^aUnless otherwise indicated, data are expressed as number (percentage) of patients
^bMultivariate analysis included the following variables: race, mode of delivery, gestational age, birth weight, maternal GBS status, adequate antepartum antibiotics, maternal pyrexia, serotypes. Gender was not included as logistic regression was done for variables on univariate analysis where p < 0.2
^c2 missing data for LOD
^dPreterm is defined as gestational age of less than 37 weeks
^eProlonged rupture of membrane is defined as rupture of membrane for more than 18 h before delivery
^fOdds ratio is invalid as there were no EOD cases with prolonged rupture of membrane
^g12 missing data; 10 and 2 isolates were not serotyped for LOD and EOD, respectively

ISSN: 1471-2334