Koh Cheng Thoon

Impact of an Antimicrobial Stewardship Program on the Use of Carbapenems in a Tertiary Women's and Children's Hospital, Singapore

Antimicrobial stewardship programs (ASPs) promote the judicious use of antimicrobials by limiting inappropriate use. This article evaluates the impact of a prospective‐audit‐and‐feedback ASP implementation on the appropriate utilization of carbapenems in a tertiary pediatrics and obstetrics/gynecology hospital in Singapore (KKH) after the establishment of an ASP in July 2011.

Bioaerosol Sampling in Clinical Settings: A Promising, Noninvasive Approach for Detecting Respiratory Viruses

Abstract Background Seeking a noninvasive method to conduct surveillance for respiratory pathogens, we sought to examine the usefulness of 2 types of off-the-shelf aerosol samplers to detect respiratory viruses in Singapore. Methods In this pilot study, we ran the aerosol samplers several times each week with patients present in the patient waiting areas at 3 primary health clinics during the months of April and May 2016. We used a SKC BioSampler with a BioLite Air Sampling Pump (run for 60 min at 8 L/min) and SKC AirChek TOUCH personal air samplers with polytetrafluoroethylene Teflon filter cassettes (run for 180 min at 5 L/min). The aerosol specimens and controls were studied with molecular assays for influenza A virus, influenza B virus, adenoviruses, and coronaviruses. Results Overall, 16 (33.3%) of the 48 specimens indicated evidence of at least 1 respiratory pathogen, with 1 (2%) positive for influenza A virus, 3 (6%) positive for influenza B virus, and 12 (25%) positive for adenovirus. Conclusions Although we were not able to correlate molecular detection with individual patient illness, patients with common acute respiratory illnesses were present during the samplings. Combined with molecular assays, it would suggest that aerosol sampling has potential as a noninvasive method for novel respiratory virus detection in clinical settings.

A 15-year retrospective analysis of prognostic factors in childhood bacterial meningitis.

This retrospective chart review aimed to identify factors in childhood bacterial meningitis that predicted disease severity and long‐term outcome.

IMPACT OF A CARBAPENEM ANTIMICROBIAL STEWARDSHIP PROGRAM ON PATIENT OUTCOMES

ABSTRACT Antimicrobial stewardship programs (ASPs) aim to improve appropriate antimicrobial use. However, concerns of the negative consequences from accepting ASP interventions exist, particularly when deescalation or discontinuation of broad-spectrum antibiotics is recommended. Hence, we sought to evaluate the impact on clinical outcomes when ASP interventions for inappropriate carbapenem use were accepted or rejected by primary providers. We retrospectively reviewed all carbapenem prescriptions deemed inappropriate according to institutional guidelines with ASP interventions between July 2011 and December 2014. Intervention acceptance and outcomes, including carbapenem utilization, length of stay, hospitalization charges, 30-day readmission, and mortality rates were reviewed. Data were analyzed in two groups, one in which physicians accepted all interventions (“accepted”) and one in which interventions were rejected (“rejected”). A total of 158 ASP interventions were made. These included carbapenem discontinuation (35%), change to narrower-spectrum antibiotic (32%), dose optimization (17%), further investigations (including imaging and procalcitonin) (11%), infectious diseases referral (3%), antibiotic discontinuation (other than carbapenem) (1%), and source control (1%). Of 220 unique patients, carbapenem use was inappropriate in 101 (45.9%) patients. A significant reduction in carbapenem utilization was observed in the accepted group versus rejected group (median defined daily doses, 0.224 versus 0.668 per 1,000 patient-days, respectively; P < 0.001). There was a significant reduction in 30-day mortality in the accepted (none) versus rejected group (10 deaths, P = 0.015), but there were no differences in length of stay, hospitalization charge, or 30-day readmission rates. Hypotension was independently associated with mortality in multivariate analysis (odds ratio, 5.25; 95% confidence interval, 1.34 to 20.6). In our institution, acceptance of carbapenem ASP interventions did not compromise patient safety in terms of clinical outcomes while reducing consumption.

Active surveillance of adverse events following childhood immunization in Singapore

INTRODUCTION In Singapore, reporting of adverse events following immunization (AEFI) was historically passive. In 2009, Health Sciences Authority collaborated with KK Womens and Childrens Hospital to perform active surveillance for AEFI. We report the methodology and initial findings of this surveillance following childhood vaccines. METHODS From April 2010 to March 2012, we screened all paediatric admissions for possible relationships to vaccination, excluding elective admissions, and performed causality assessment for each case using standardized definitions for certain, probable, possible and unlikely. Baseline demographics, data on implicated vaccines and clinical details including severity and outcomes were collected. Total hospital admissions were used to calculate rates of AEFI. RESULTS We screened 45,571 (80%) of 56,526 admissions, and evaluated 1988 (4.4%) children. Median age at presentation was 3.1 months, while median interval from vaccination to symptom onset was 6 days. There were 311 (15.6%) children with AEFI that were considered possibly, probably or certainly associated with vaccines. However, 98.8% recovered without any long-term sequelae. The hospital-based active surveillance of AEFI enabled the detection of a 5-fold increase (95% CI 1.2-33.1) in BCG-associated regional lymphadenitis in April 2010, which triggered follow-up safety analysis to guide public health advice. CONCLUSIONS Hospital-based active surveillance can enhance signal detection and follow-up investigations of AEFI. Subsequently, public health bodies are better equipped to maintain public confidence in vaccination programmes and physicians are able to provide relevant advice to parents. It also allows for a better understanding of risk-benefit ratios of specific vaccines and aids the generation of public health vaccination policy.

“I wouldn’t really believe statistics” – Challenges with influenza vaccine acceptance among healthcare workers in Singapore

BACKGROUND Influenza vaccine acceptance among healthcare workers (HCWs) is a worldwide problem, but relatively little research has focussed on Asia, including Singapore. Despite widespread access and recommendations from public health authorities, influenza vaccine uptake remains suboptimal among HCWs. METHODS Our qualitative study used focus group discussions to identify and explain factors limiting influenza vaccine acceptance among HCWs in Singapore. A total of 73 doctors, nurses, allied health and ancillary staff across three public hospitals were included. RESULTS Challenges identified include a fear of contracting influenza from vaccination exacerbated by negative anecdotes regarding vaccine safety and efficacy, distrust of published efficacy data, uncertainty regarding relevance of existing data for Singapore, reluctance to introduce chemicals or overmedicate, pain from injection, low risk attributed to influenza and limited awareness of influenza transmission with a preference for alternatives in patient protection. Differences in attitudes were observed across vocational groups. Lack of overt promotion by hospital leadership in some institutions, perceived vaccine hesitancy among doctors, access, and work culture that implicitly encourages working through illness were further barriers. CONCLUSION Our findings highlight a combination of misperceptions about influenza vaccination and cognitive biases at the individual level, and challenges at the institutional level limiting uptake. Findings indicate an urgent need to provide targeted education and communication. Rather than providing more data, we recommend a widely-disseminated, locally-compiled synthesis addressing specific concerns of hesitant HCWs. Tailoring interventions to specific vocational groups should be considered. Institutional norms and culture may have a powerful influence in setting default behaviours: more effort is needed in improving influenza vaccine promotion and priority at some institutions, integrating vaccine-related communication with other infection control communication and addressing influenza vaccine hesitancy among doctors as a priority. Finally, further study of strategies to address cognitive biases affecting influenza vaccine acceptance in Singapore is desirable.

Comparing monovalent and combination hepatitis B vaccine outcomes in children delivered by mothers with chronic hepatitis B: Hepatitis B vaccine outcome

We compared the vaccine effectiveness of monovalent and combination hepatitis B vaccine regimens in infants born to chronic hepatitis B carrier mothers.

Prevalence of Respiratory Polyomaviruses Among Pediatric Patients With Respiratory Symptoms in Singapore

Background: Although WU polyomavirus (WU) and KI polyomavirus (KI) have been demonstrated to infect the human respiratory tract, it remains unclear if WU or KI cause human disease. We sought to further investigate the relationship between WU and KI infection and respiratory disease in a pediatric population with respiratory symptoms in Singapore. Methods: We conducted a cross-sectional study of pediatric patients with respiratory symptoms in a Singaporean pediatrics hospital. Upon consent, residual respiratory samples from pediatric inpatients, previously screened for common respiratory viruses, were collected and further screened for WU and KI using qPCR. The amplicons of positive samples were sequenced for confirmation. The severity of a patients illness was assessed by chart review post-discharge looking for clinical markers of respiratory status such as presenting symptoms, diagnoses, and interventions. Results: From December 2016 to April 2017, 201 patients with residual respiratory samples were enrolled in the study. The average age of all participants recruited was 45 months. WU and KI were detected in 13% (26/201) and 3% (6/201) of patients, respectively. Conducting bivariate and multivariate modeling, patients with WU or KI positivity were not at increased risk of SARI, need for additional oxygen, intravenous fluids, and did not receive additional oral antibiotics or bronchodilators during admission. In contrast, patients with RSV detections were at increased risk of requiring supplemental oxygen during hospital admission. Conclusion: While limited in sample size, our pilot study data do not support the hypothesis that molecular evidence of WU or KI was associated with increased morbidity among a sample of general, pediatric patients with respiratory illness in Singapore.

Infant With Invasive Nontyphoidal Salmonellosis and Mastitis.

Mastitis in early infancy is uncommon.1 Mastitis cases in full-term neonates and nonlactational mastitis in older children have been reported, with Staphylococcus aureus being the most common pathogen, but concurrent bacteremia or meningitis is rare.1-3 Gram-negative enteric bacteria as pathogens have been uncommonly reported, and mastitis due to Salmonella typhi3 and nontyphoidal Salmonella (NTS) is rare.4 Empiric management of mastitis and breast abscess in infancy according to the available literature includes parenteral and oral antibiotics with antistaphylococcal activity and surgical interventions such as aspiration and/or incision and drainage in the presence of abscesses.1,2 Here, we report the case of a previously well 7-week-old infant girl with invasive NTS infection and mastitis confirmed by respective cultures.

Could a fever and rash after the measles, mumps and rubella vaccination indicate wild-type measles?

1.Department of Paediatrics, KK Women’s and Children’s Hospital, Singapore 2.Department of Pathology and Laboratory Medicine, KK Women’s and Children’s Hospital, Singapore 3.Duke-National University of Singapore Graduate Medical School, Singapore 4.Infectious Disease Service, Department of Paediatrics, KK Women’s and Children’s Hospital, Singapore 5.Yong Loo Lin School of Medicine, National University of Singapore, Singapore