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

BACKGROUND: The current group B streptococcal (GBS) preventive measures had reduced invasive GBS early onset disease (EOD) incidences worldwide, but the late onset disease (LOD) incidences had remained unchanged. Administration of a safe and effective GBS vaccine in addition to the current strategies were thought to be the next steps in reducing the incidences of invasive GBS infection especially LOD. In this study, we aimed to examine the causative GBS serotypes in invasive GBS disease, determine the incidences of EOD and LOD, and compare the risk factors between EOD and LOD. METHODS: A retrospective study of infants ≤ 90-day-old over an 8-year period (2010-2017). The incidences of EOD and LOD were obtained by using patients with EOD and LOD who were born in our institution as the numerator and the live births in our institution per year of the study period as the denominator. Available GBS isolates were serotyped by the National Public Health Laboratory using capsular serotyping methods. The risk factors of EOD and LOD were compared. RESULTS: A total of 71 infants were identified; 16 (22.5%) and 55 (77.5%) of them had EOD and LOD, respectively. Serotype III (n = 42, 71.2%) was the most common serotype amongst the 59 isolates available for serotyping. Serotypes Ia, Ib, II, III, and V accounted for 98.3% (n = 58) of the invasive GBS diseases. The overall incidence was 0.42 per 1000 live births. The mean incidences of EOD and LOD were 0.13 per 1000 live births and 0.29 per 1000 live births, respectively. On multivariate analysis, risk factors for LOD as compared to EOD were: Chinese ethnicity (OR 27.1, 95% CI 3.0-243.1, p = 0.003) and negative/unknown maternal GBS status (OR 20.0, 95% CI 2.0-250.0, p = 0.012). Prematurity and intrapartum risk factors (peripartum maternal pyrexia, prolonged rupture of membrane) of EOD were not associated with LOD. CONCLUSIONS: The LOD incidence had remained higher than EOD incidence in our cohort. A GBS vaccine that covers the major causative serotypes found in our cohort can potentially reduce the overall GBS disease burden in the country.

Acute suppurative thyroiditis in children secondary to pyriform sinus fistula.

Acute suppurative thyroiditis (AST), a potential complication of pyriform sinus fistula (PSF), is a rare clinical condition as the thyroid gland is remarkably resistant to infections. Lack of awareness of the entity contributes to the rarity and frustrating recurrences. We performed a retrospective review of all cases of AST due to PSF treated at our institution over a 10-year period. The clinical data, investigations, operative findings and procedures, microbial culture reports and follow-up were recorded and analyzed. Between January 1997 and September 2006, 12 cases (8 males and 4 females) of AST due to PSF were treated. Nine patients (75%) underwent successful complete excision, seven of whom had initial incision and drainage procedures. In three patients (25%) with recurrence, one underwent complete excision at a later procedure, one patient had multiple recurrences with six incision and drainage procedures and two failed attempts of excision of PSF before final successful complete excision. The third patient is awaiting re-excision of the PSF tract. All patients, except the one awaiting re-excision, are well with no further recurrences during the follow-up period that ranged from 18 to 96 months (median, 46.5 months). AST due to PSF is a challenging entity in terms of diagnosis and management as recurrences are common despite meticulous dissection. High index of suspicion and radiological investigations such as barium studies and computed tomography scan aid in the delineation and excision of the fistulous tract.

Staphylococcus lugdunensis carrying the mecA gene causes catheter-associated bloodstream infection in premature neonate.

A premature neonate had a catheter-associated bloodstream infection due to Staphylococcus lugdunensis. The MIC of oxacillin for the strain was >256 microg/ml, and the mecA gene of S. lugdunensis was detected by PCR. The infection was resolved after removal of the line and treatment with vancomycin for 2 weeks.